HBW 15 - Foreword on conservation of the world's birds, by Stuart Butchart, Nigel Collar, Alison Stattersfield & Leon Bennun.

View foreword in PDF format: 


The Handbook of the Birds of the World (HBW) began chronicling all of the world’s bird species with the publication of Volume 1 in 1992. By 1999, Volume 5 had appeared, carrying a Foreword describing the factors that can be used to assess the conservation status of species, presenting the then newly developed Red List criteria of the International Union for Conservation of Nature (IUCN), and discussing why such status assessments are important (Collar 1999). Conservationists had already been calling for action to save the planet’s dwindling natural resources for over a century, with limited effect. By the turn of the twenty-first century this message was at last starting to get through. The stark evidence that human impacts were impoverishing our world, and, as a result, our own lives, was finally awakening a public conscience and seeping into political awareness.

In response, at the World Summit on Sustainable Development in 2002, the world’s governments committed themselves to achieve a significant reduction in the rate of biodiversity loss by 2010. The “2010 target” has focused considerable attention on biodiversity and how we can measure its status. It has also been formally incorporated into the United Nations Millennium Development Goals (MDGs) for environmentally sustainable development. Biodiversity, and the ecosystem services it underpins, are fundamental for achieving these goals. Biodiversity conservation is vital for long-term environmental sustainability, and directly affects issues such as health, water, sanitation and many other aspects of peoples’ lives (Millennium Ecosystem Assessment 2005, TEEB 2008).

Almost two decades on from the start of its journey, HBW is nearly complete. Using the IUCN Red List categories and criteria for assessing species’ conservation status described in HBW 5 (see also IUCN 2001), BirdLife International and Lynx Edicions published Threatened Birds of the World in 2000 (BirdLife International 2000): a detailed analysis of the status, distribution, habitats, ecology and actions needed for threatened species. This has since been comprehensively updated at four-yearly intervals (BirdLife International 2004a, 2008a), with partial annual updates. These species assessments, along with a growing body of information on key sites—“Important Bird Areas” (IBAs)—and habitats for the world’s birds, formed the basis of State of the World’s Birds (BirdLife International 2004b, 2008b), which in turn underpins the review here. Where they are not specifically cited, data come from the latest version of the IUCN Red List assessments for birds (BirdLife International 2010a), including abbreviated Red List categories for species of conservation concern. In the light of the 2010 target, our aim here is to review the status of the world’s birds, the most important pressures they face, and how these threats can be tackled.

Birds as biodiversity indicators

While we focus on birds, our conclusions are relevant to biodiversity more generally, because birds are effective indicators for a number of reasons. Birds occur almost everywhere in the world and in virtually all habitats. Their biology and life-histories are relatively well understood; their taxonomy is well known and relatively stable, and their populations are often easily surveyed and counted. Birds are mobile and responsive to environmental change, and there are enough bird species to show meaningful patterns. Birds also have economic importance in their own right. However, birds are less effective indicators for some habitats and are generally less specialised within micro-habitats than, for example, insects or plants; so, at a local scale, patterns of bird distribution may not always match well those of other taxa (Pearson 1995, Lawton et al. 1998). Nevertheless, networks of sites selected as important for birds also capture most other biodiversity (Howard et al. 1998, Brooks et al. 2001) and, at a larger scale, birds are very useful indicators of species richness and endemism patterns (Bibby et al. 1992, Stattersfield et al. 1998, Burgess et al. 2002, Rodrigues 2007). Most importantly, bird population trends tend to integrate several ecological factors and therefore provide a useful indication of environmental change (Donald et al. 2001, Gregory et al. 2003).

As indicators, the most significant advantage of birds is that we have so much information about them. Indeed, HBW is weighty proof that birds are considerably better known than any other class of organism. Again, the character of birds provides the reason for this. Most birds have several or many of the following attributes: they are common, diurnal, conspicuous, colourful, beautiful, vocal, musical and responsive to feeding, making them attractive, interesting, watchable and identifiable. In most places in the world there are good (but not overwhelming) numbers of species. Watching birds is therefore highly popular. For example, c. 46 million people in the USA (c. 20%) spend time observing and identifying birds (USFWS 2003a), and in doing so contributed US$36 billion to the US economy in 2006 alone (La Rouche 2009), while 20 million people (c. 30%) in the UK are birdwatchers or regularly feed birds in their gardens (Beolens 2010).

Scientific research on birds is intensive, and expanding. A “Web of Science” keyword search reveals that since 1990 there have been over 160,000 articles in mainstream academic journals with the word “bird” in the title or abstract—over 20 a day on average! There are numerous professional ornithologists, but in addition many birdwatchers are skilled observers, and contribute high-quality data to “citizen science” programmes. Information on bird distribution, migration, ecology and behaviour is collected from all over the world, by thousands of individuals and organisations. In many countries, data are gathered through extensive bird-ringing programmes (e.g. 1·1 and 0·8 million birds per year are ringed in the USA and UK respectively: BTO 2009, USGS 2010).

The level of interest in birds is reflected by the extraordinary number of field guides and books that have been published about them, with individual guides covering nearly every country in the world, and many others focusing on individual bird families. This huge array of information is also being brought together in a meaningful way for conservation. Since 1980, BirdLife International (and its precursor the International Council for Bird Preservation) has published Red Data Books, presenting comprehensive information on all globally threatened bird species. The latest in this series, Threatened Birds of Asia, cites over 7000 references (BirdLife International 2001), while the latest version of Threatened Birds of the World (BirdLife International 2008a) cites 5900 references. BirdLife’s World Bird Database (WBDB), initiated in 1994, manages extensive information on all c. 10,000 species, and a similar number of IBAs and 218 Endemic Bird Areas (EBAs: areas of endemism supporting at least two “restricted-range” species). What do all these data tell us about the conservation status of the world’s birds in 2010?


In his Foreword to HBW 7, Fuller (2002) documented 75 bird species that had gone extinct since 1600, plus a number of taxa whose taxonomic status and/or survival were uncertain. Some of these are now considered to have died out much earlier, while others are treated as Critically Endangered (CR), as there is still hope that individuals may survive. BirdLife lists a total of 132 recently extinct bird species. The additions to Fuller’s list are (a) species that went extinct after 1500 (the cut-off date used by BirdLife and IUCN) but before 1600, (b) taxa whose taxonomic status and/or extinction are no longer considered uncertain, and (c) other extinct taxa shown to be good species in recent years. BirdLife classifies an additional four species as Extinct in the Wild (EW), with populations surviving only in captivity.

Some species currently categorised as CR may also be extinct, but cannot be designated as such until we are as close to certain as possible. This is in order to avoid giving up on them prematurely, termed the “Romeo error” by Collar (1998) in discussing the case of Cebu Flowerpecker (Dicaeum quadricolor) CR. This bird was rediscovered in 1992 after 86 years without a record (Dutson et al. 1993), having been written off as extinct at least 40 years earlier on the presumption that no forest remained on the island of Cebu (Magsalay et al. 1995). A total of 13 CR species are tagged as Possibly Extinct (and one as Possibly Extinct in the Wild) because they are, on the balance of evidence, likely to have died out, but there is a small chance that some wild individuals survive undetected (Butchart et al. 2006a). Adding these to the totals above indicates that 150 bird species may have been lost since 1500. Many more bird species were driven extinct in historic times by human expansion around the world, for example, by the colonisation of Polynesia (Steadman 1995).

Extinctions are continuing: 18 species were lost in the last quarter of the twentieth century, and three are known or suspected to have gone since 2000. The last known wild Spix’s Macaw (Cyanopsitta spixii) CR, Possibly Extinct in the Wild disappeared in Brazil towards the end of 2000, the last two wild Hawaiian Crows (Corvus hawaiiensis) EW disappeared in June 2002, and the last known Poo-uli (Melamprosops phaeosoma) CR, Possibly Extinct also from Hawaii, died in captivity in November 2004.

Most extinctions (88%) have been on islands (Butchart et al. 2006a), even though most bird species (>80%) live on continents (Johnson & Stattersfield 1990). Many island extinctions resulted from the introduction of invasive alien species such as cats, rats and goats, which devoured the native species or degraded their habitats. Native species on oceanic islands are often particularly susceptible to introduced predators, having lost their natural defences after evolving in isolation for many thousands of years. The extinction rate on islands may be slowing, presumably because many susceptible species are already extinct, while conservation interventions are successfully improving the status of some of the remainder. By contrast, the extinction rate on continents is increasing (Fig. 1), and the continuing large-scale destruction of natural habitats bodes ill for many continental bird species.

Avoiding the “Romeo error”, and not designating a species Extinct until it certainly is, may lead to a modest underestimation of extinction rates. This is compounded by time-lags before the last individuals of a species disappear following habitat loss. In Kakamega Forest, Kenya, the number of species in habitat fragments was found to decline exponentially after isolation, with a half-life of 23–80 years, i.e. half the number of species that are expected eventually to disappear are lost in the first 23–80 years following isolation (Brooks et al. 1999). This suggests that many species threatened by habitat loss will be “committed to extinction” unless conservation action is implemented urgently.

Threatened species

Using the IUCN Red List criteria and categories (IUCN 2001), BirdLife’s 2010 assessment of all the world’s birds shows that 1240 species (12·5% of the 9895 extant species, or one in eight) are threatened with global extinction. These comprise 190 species classed as CR (1·9%), 372 as Endangered (EN, 3·8%) and 678 as Vulnerable (VU, 6·9%). An additional 838 species (8·5%) are considered Near Threatened (NT) because they are close to qualifying as globally threatened. Hence a total of 2078 species (a fifth of all the world’s birds) are assessed as being of significant global conservation concern. Only 62 species (0·6% of the total) are considered insufficiently known for their threat status to be determined, and so are classified as Data Deficient, far fewer proportionately than other taxonomic classes, such as mammals (15·5%), amphibians (25·4%) and corals (17·5%) (Vié et al. 2008, Butchart & Bird 2009), precisely because of the greater knowledge about birds.

There are particularly high proportions of threatened species among albatrosses (77%, 17 out of 22 species), cranes (73%, 11 out of 15), penguins (61%, 11 out of 18), petrels and shearwaters (43%, 35 out of 82) and guans (34%, 17 out of 50). Furthermore, families and genera with few species have disproportionately high numbers of threatened species (Purvis et al. 2000), and larger-bodied species and those with low reproductive rates (owing to small clutch sizes) are also more likely to be threatened (Bennett & Owens 1997).

The populations of 80% of threatened birds (992 species) are below 10,000 individuals, and 42% (524 species) are below 2500 individuals. Some 60 species have tiny populations that may support no more than 50 individuals worldwide. Eighty-two percent of threatened birds are declining; and for 36% (449 species) the declines are rapid (over 30% in ten years or three generations). Eighteen species have declined by over 80% over the past ten years or three generations. For example, numbers of Mariana Crow (Corvus kubaryi) CR fell from 1318 birds in 1982 to 85 pairs in 2008 (Amar et al. 2008), and Spoon-billed Sandpiper (Eurynorhynchus pygmeus) CR declined from an estimated 2000–2800 pairs in the 1970s to 150–450 pairs by 2008 (Zöckler et al. 2008). Only 118 threatened species (10% of those with trend estimates) have stable populations, and just 59 (5%) have increasing populations, almost all in response to conservation efforts, e.g. St Lucia Amazon (Amazona versicolor) VU and Mauritius Kestrel (Falco punctatus) VU.

Most threatened bird species have small or very small ranges, rendering them more susceptible to threatening processes. Forty-one species (3%) occupy ranges smaller than 10 km2, the majority on small islands. For example, Floreana Mockingbird (Nesomimus trifasciatus) CR is restricted to two tiny islets totalling just 0·9 km2 in the Galapagos Islands, Ecuador, and Cerulean Paradise-flycatcher (Eutrichomyias rowleyi) CR is restricted to 2 km2 of forest on the Indonesian island of Sangihe. Altogether 672 threatened birds (54%) qualify as threatened because their ranges are smaller than 20,000 km2 and are declining and fragmented or restricted to a few locations. In total, 346 threatened species (28%) are known from ten or fewer locations, with 296 (24%) found at five or fewer. A total of 217 CR or EN species are restricted to single sites, and hence qualify under the criteria of the Alliance for Zero Extinction (www.zeroextinction.org; see also Ricketts et al. 2005). Examples include Pale-headed Brush-finch (Atlapetes pallidiceps) CR, now restricted to a single site in southern Ecuador, Millerbird (Acrocephalus familiaris) and Nihoa Finch (Telespiza ultima), both CR and found only on Nihoa Island, Hawaii, USA.

The few threatened birds that have very large ranges (36 species or 3% have range sizes over 1 million km2) are considered threatened either because they occur at very low densities and have small declining populations, or because they have undergone extremely steep population declines. An example of the former circumstance is Lappet-faced Vulture (Torgos tracheliotus) VU, which occurs over 8·7 million km2 in Africa and the Middle East but at low population densities, with a total, declining population of 8500 individuals. Examples of the latter are provided by three Asian Gyps vultures whose numbers have decreased by up to 99% in recent years owing to poisoning by the veterinary drug diclofenac (see below).

Distribution of threatened species

All countries and territories of the world host one or more globally threatened bird species, with particularly high densities in the tropical Andes, Atlantic Forests of Brazil, eastern Himalayas, eastern Madagascar and insular South-East Asia (Fig. 2). The highest densities of threatened seabirds are found in international waters in the southern oceans, with a particular concentration around New Zealand (Fig. 3). Ten countries have more than 60 globally threatened birds, with Brazil and Indonesia heading the list, holding 123 and 119 respectively (Fig. 4). It is notable that, with dependent territories included, the USA jumps from seventh to fourth in the list of countries with the most threatened birds, supporting 97 species (22 in overseas territories), while France’s rank shifts from 144 to eight with 78 species (71 overseas). In total, 756 threatened birds (61%) have ranges confined to just one country, and 78 countries (35%) have one or more such endemic threatened birds. Again, Brazil and Indonesia top the list, with 70 and 68 endemics respectively, while the proportion of threatened species that are endemic is highest in São Tomé e Principe (90% of 10 species), Phili­ppines (81% of 73 species) and Madagascar (77% of 35 species). Conversely, the ranges of some threatened birds may cross the borders of several countries: Lesser Kestrel (Falco naumanni) VU tops the list, occurring regularly in 97 countries (and as a vagrant to 15 others) in Europe, Asia and Africa, and Wandering Albatross (Diomedea exulans) VU occurs in 17 (breeding in four and visiting the territorial seas of 13 others). Thirteen other species have ranges that encompass 30 or more countries, and 160 species are recorded from five or more countries. Hence the political responsibility for saving threatened species falls to individual countries but also requires international cooperation in both conservation action and financing.

The overall avifaunas of some countries are particularly threatened. A graph of the number of threatened species plotted against the total number of bird species per nation shows that numerous countries are situated well above the regression line, i.e. they support more threatened species than expected (Fig. 5). The ten countries with the most threatened avifaunas include seven of the most important in terms of absolute numbers of threatened birds (e.g. Indonesia, Peru and Brazil). The analysis also highlights several territories that have highly threatened avifaunas despite relatively low total avian diversity. For example, French Polynesia supports 79 bird species, of which 32 are globally threatened, and Norfolk Island (to Australia) supports 39 species, with 16 globally threatened. Some countries also hold far fewer threatened species than expected. These include very small states with no globally threatened birds (e.g. Monaco and the Faroe Islands), but also large ones such as Guyana, Suriname and Congo, with avifaunas of more than 600 species. Fortunately, few bird species are yet threatened in these countries because they still hold vast tracts of largely pristine forest and host very few restricted-range species.

Most of the world’s bird species (>80%) are continental in distribution (Johnson & Stattersfield 1990). However, just as islands have disproportionately high numbers of extinctions, so they also have disproportionately high numbers of threatened species: almost equal numbers are found on islands (583 species) as on continents (613), with few (30, 2·5%) shared between them. Oceanic islands hold more than twice as many threatened species as continental shelf islands (Fig. 6). Some small island groups harbour exceptionally high numbers of threatened birds: 33 on Hawaii (USA) and 14 each on the Northern Marianas (to USA) and Galapagos (Ecuador).

Habitats of threatened species

Forests are the most important habitat for threatened birds, supporting 946 species (76%). Shrubland (scrub, bushland and thicket habitats, supporting 339 species, 27%), inland wetlands (211 species, 17%) and grasslands (204 species, 17%) are the next most important habitats (with some species occurring in multiple habitat types; Fig. 7). Only 347 threatened species (28%) utilise what are termed artificial habitats (compared with 45% of all birds), largely because threatened species tend to be less tolerant of habitat modification. These species usually depend on adjacent natural or semi-natural habitats for breeding or feeding, but are able to use human-modified habitats to some extent. Threatened birds are found in all forest types (Fig. 8), but tropical/subtropical lowland and montane moist forest are the most important, supporting 550 species (58% of forest-dwelling threatened species) and 439 species (46%) respectively, with tropical/subtropical dry forest supporting 157 (17%). Threatened forest birds tend to be intolerant of habitat degradation: 76% (709 species) show a strong dependency on intact forest.

Recent trends in threatened species

The Red List Index (RLI) for birds tracks trends in their overall extinction risk, with values relating to the proportion of species expected to remain extant in the near future without additional conservation action (Butchart et al. 2004, 2007). It shows (Fig. 9) that there has been a steady and continuing deterioration in the status of the world’s birds since 1988 (when the first comprehensive global assessment was carried out: Collar & Andrew 1988). The RLI is based on the number of species in each Red List category and the number moving between categories (when the entire set is re­assessed) as a result of genuine changes in status (i.e. excluding moves resulting from improved knowledge or taxonomic changes: Butchart et al. 2004, 2005, 2007). Although 40 species have improved in status since 1988 (sufficient to be downlisted to a category of lower threat), 234 have deteriorated in status (sufficient to be uplisted to a category of higher threat), giving a net decline in the index overall.

The RLI can be disaggregated to show trends for different subsets of species. Birds in terrestrial, freshwater and marine ecosystems (including coastal habitats) have all declined in status over the last 20 years (Fig. 10). Marine species are of particular concern: they are substantially more threatened on average (with the lowest RLI values), and have declined faster than others. Similarly, birds in all regions have declined in status, but those in Oceania are substantially more threatened on average, and have declined fastest (Fig. 11), often owing to the detrimental impacts of invasive alien species on Pacific islands. In the Indomalayan realm, there was a sharp decline in the status of birds between 1994 and 2000. This was a consequence of the destruction of forests in the Sundaic lowlands of Malaysia and particularly Indonesia, which escalated in the late 1990s. Some species groups have been impacted very seriously by human activities and have an exceptionally high proportion of species listed as globally threatened. Pelagic seabirds (those using the open seas) are substantially more threatened and declining faster than other groups (Fig. 12), owing to a combination of marine threats (notably from incidental mortality in longline fisheries) and threats at breeding colonies (particularly the impacts of invasive alien species).

Common bird declines

In much of the world, familiar common bird species may not yet be globally threatened, but are nevertheless in decline (Fig. 13). At least 40% of bird species worldwide (3967) have declining population trends, compared with 44% that are stable (4393), 7% that are increasing (653) and 8% with unknown trends (823). Reductions in population and/or distribution have been documented across both temperate and tropical regions, and in farmlands, forests, wetlands and other habitats, indicating widespread environmental problems. The species with stable or increasing populations tend to be those that can thrive in human-altered habitats, although some are benefiting from conservation efforts. Detailed information on declines in common birds is patchy: below we look at examples where trends have been quantified.


In Europe, Wild Bird Indices (WBIs) show that populations of farmland specialist birds (such as Corn Bunting Miliaria calandra) have declined by 48% since 1980, with decline rates greatest in the late 1970s and early 1980s (Fig. 14; Gregory et al. 2005, 2008, PECBMS 2009, www.ebcc.info). Forest species have fluctuated in numbers over the past three decades, with declines in northern and southern Europe contrasting with apparently stable or increasing trends in parts of central and eastern Europe (Gregory et al. 2007). Populations of long-distance migrants that breed in Europe and winter in sub-Saharan Africa (such as Spotted Flycatcher Muscicapa striata) have suffered sustained and often severe declines over the past few decades. Over 40% of Afro-Palearctic migrants have undergone substantial declines since 1970 (Sander­son et al. 2006), whereas residents and short-distance migrants breeding in the same habitats in Europe have not. Varying combinations of multiple threats, including habitat degradation on breeding grounds in Europe, hunting in southern Europe and North Africa, loss of staging areas, reduced over-winter survival (owing to reduced rainfall and increased agricultural intensification) and possibly climate change (asynchrony in the timing of migration and resource availability), seem likely to be driving the declines, but it remains extremely difficult to identify the most significant among them.

North America

In North America, WBIs (Fig. 15) show that since 1968 populations of grassland species (such as Lark Bunting Calamospiza melanocorys) have declined by 28%, aridland species (such as Scaled Quail Callipepla squamata) by 27% and forest species (such as Kentucky Warbler Oporornis formosus) by 2% overall (but by 25% in eastern forests) (US NABCI Committee 2009). The dramatic population declines in grasslands and aridlands are largely attributed to habitat loss driven by agricultural expansion and intensification, as well as infrastructure and housing development, mining and other energy development. Climate change is also a significant threat, especially for tundra-breeding species. In parallel with results from Europe, over half the Neotropical migratory birds in North America have suffered substantial declines over the past 40 years, particularly since the 1980s (e.g. Western Wood-pewee Contopus sordidulus). The reasons are unclear, but forest fragmentation in breeding areas and deforestation in non-breeding ranges may be important. In contrast, indicators for wetland specialists (such as Redhead Aythya americana) show that their populations have increased 56% since 1968, probably as a consequence of changes in precipitation, land-use and management practices.


In Australia, too, common and widespread birds have declined sharply in recent years, most notably across the Murray-Darling Basin (covering a large part of south-east Australia). Woodland, grassland and heathland bird populations all appear to be in decline (Olsen 2008). Detailed indices based on atlas data are currently available only at a subregional scale (for eight catchments in New South Wales), but show consistently negative trends in common species such as Australian Magpie (Gymnorhina tibicen) and Eastern Rosella (Platycercus eximius) (Cunningham & Olsen 2009). Aerial surveys of waterbirds across eastern Australia also show that their overall numbers are much lower than in the 1980s. Shorebird numbers, in particular, have plummeted over the last two decades, including both migrants (such as Far Eastern Curlew Numenius madagascariensis and Curlew Sandpiper Calidris ferruginea), and residents (such as Banded Lapwing Vanellus tricolor and Red-necked Avocet Recurvirostra novaehollandiae) (Kingsford & Porter 2008).

Waterbirds worldwide

Despite the positive trends noted above for waterbirds in North America, 40% of 1200 waterbird populations worldwide (for which trends are known) are declining, with only 17% increasing (Delany & Scott 2006). Reliable trend data are unavailable for the remaining 1105 waterbird populations, and the availability of information varies regionally. Data from Europe (where estimates are available for 73% of 351 populations) show a similarly high proportion (41%) of populations in decline, while in Asia 59% of populations with known trends are declining (Delany & Scott 2006). For shorebirds (one of the better known groups), the proportion of declining populations has increased from 41% in the 1980s to 52% in the 2000s (Fig. 16; Davidson & Stroud 2010). For example, numbers of the rufa subspecies of Red Knot (Calidris canutus), which migrates between the Canadian Arctic and Tierra del Fuego, fell from 100,000 individuals in 1989 to just 17,200 in 2006, mainly owing to humans over-harvesting key food sources at important stop-over sites (Baker et al. 2004).

African raptors

In other regions and for other species groups, information is patchier but trends are generally negative. Two recent studies highlight declines in African raptors, which are likely to be symptomatic of trends in birds in the African countryside more generally. Surveys in Burkina Faso, Mali and Niger in 1969–1973 and 2003–2004 showed that eleven large eagle species declined by 86–98% over the 30-year period outside protected areas. Six large vulture species also suffered dramatic declines outside protected areas (Fig. 17), almost certainly linked to rapid human population expansion and accompanying habitat degradation, over-hunting of wild ungulates (antelopes, gazelles, etc.), increased disturbance and the poisoning of carcasses (Thiollay 2006a, 2006b, 2007a, 2007b). In Botswana too, large raptors seem to have declined severely outside protected areas (Fig. 18; Herremans & Herremans-Tonnoeyr 2000). The effect was greatest for large eagle species, but similar patterns were found for smaller raptors. Again, livestock overgrazing and the widespread depletion of potential prey are likely to be important drivers (Herremans 1998).

The principal threats to birds

Human activity is the predominant cause of population declines and extinction risk in birds. The most important way this impacts species is through habitat loss, including destruction and degradation of forests by agriculture and unsustainable forestry, loss of wetlands to drainage, development and pollution, and degradation of other habitats through conversion and modification. Habitat destruction and degradation are often driven by a combination of direct interconnected threats whose importance varies regionally. For deforestation, small-scale and subsistence agriculture is the most important, causing half of forest loss in Africa and 40% in the Asia-Pacific region and South America (Blaser & Robledo 2007). Cultivation of commercial crops is the motivation for 24% of forest clearance in Asia-Pacific, and a fifth in South America and Africa, with the key crops in these regions including oil palm, soya and cocoa respectively. Timber extraction for wood, paper and packaging causes a quarter of deforestation in Asia-Pacific, 15% in Africa and 12% in South America. Extraction of fuelwood contributes 8–10% of forest loss in each region, while clearance for cattle ranching is largely a South American phenomenon, driving 20% of forest loss there, but less than 5% in Africa and Asia-Pacific. Often these processes are interconnected, with logging companies initially extracting timber, followed by clearance of remaining vegetation for commercial crops, with small-scale and subsistence agriculture and fuelwood extraction then spreading along the access routes created. Fires started deliberately for clearance also often spread and damage adjacent areas of intact forest, further exacerbating impacts and expanding the area destroyed or degraded.

Similarly, habitat loss in wetlands is caused by a combination of drainage, in-filling and conversion of lakes and marshes for agriculture, commercial use and residential development; damming, canalisation, water extraction and disruption to flow regimes of the world’s rivers for transportation, hydropower, irrigation and commercial and domestic water supplies; and reclamation, modification and pollution of coastal wetlands for agriculture, aquaculture and industrial and urban development.

Across all habitats and for all bird species, the three most important threats are agriculture, which puts 911 threatened birds (73%) at risk, logging and wood harvesting, impacting 669 species (54%), and invasive alien species, affecting 422 species (34%) (Fig. 19). Hunting and trapping (for food, pets and sport), residential and commercial development, energy production and mining, changes to fire regimes, pollution, fisheries and, increasingly, climate change, are also having serious negative impacts. A similar picture emerges from examining the drivers of changes in the status of species leading to their being re-categorised on the IUCN Red List since 1988 (Fig. 20). The most prominent is agriculture, followed by hunting/trapping and invasive alien species. Threats impact bird populations in different ways (termed “stresses” by IUCN: Salafsky et al. 2008). Habitat destruction and degradation, as described above, is the most important consequence of threats for 1189 threatened species (96%), while threats primarily causing problems through direct mortality and reduced reproductive success affect 682 species (55%) and 413 species (33%) respectively (Fig. 21).

Similar threats impact the key sites for the world’s birds: Important Bird Areas (IBAs). Nearly half (47%) of IBAs with data are threatened by agriculture and aquaculture, 39% are impacted by hunting and trapping, 35% by invasive alien species and 28% by logging and harvesting plants (Fig. 22). Interestingly, human disturbance is identified as a key threat for 40% of IBAs, reflecting the great pressures IBAs are under from expanding human populations.

We review these key threats to the world’s birds in turn.


The spread and intensification of agriculture, resulting in habitat destruction and de­gradation, is the greatest threat to biodiversity, particularly in the tropics (Vié et al. 2008). This is driven by expanding human populations, increasing food needs, growing demands for animal protein, and increasing production of biofuels.

Expanding and intensifying cultivation of annual and perennial crops such as cereals, pulses and vegetables is the most important form of agriculture in terms of its impact on threatened birds (affecting 810 species, 89% of those threatened by agriculture), with industrial-scale farming impacting 348 species (38%) and small-holder farming affecting 368 species (40%). Livestock farming is a key pressure on 400 species (44%), with industrial-scale livestock farming (231 species, 25%) slightly more significant than small-holder livestock farming (206 species, 23%). Wood plantations (principally for timber, paper pulp and palm oil) affect 125 species (14%). We discuss a selection of examples here of the ways in which agricultural growth is destroying natural habitats and threatening the world’s birds.


Soybean is one of the world’s major staples, being used for vegetable oil, a protein substitute in food, and, most importantly, livestock feed for cows, pigs and chickens (the destination for 80% of the world’s soy production). It is also in increasing demand for biodiesel. Most soybean is grown in South America, where production increased 15% per year during 1999–2004, with Brazil poised to overtake the USA as the largest single producer (Mardas et al. 2009). Expansion of soybean cultivation is a major driver of deforestation, but production is also expanding into the cerrado, a biodiverse savanna habitat supporting over 900 bird species, including Kaempfer’s Woodpecker (Celeus obrieni) CR and Cone-billed Tanager (Conothraupis mesoleuca) CR. By 2004, farming, primarily for soybean, had reduced the area of cerrado by 57%, with 1% of the remaining habitat being converted annually (Butler 2007a, 2007b). Apart from threatening many bird species, use of soybean as a biofuel is ineffective for tackling climate change: cerrado soil and vegetation have high levels of stored carbon, so it takes 37 years to replace the carbon lost when cerrado is converted to soybean production (Fargione et al. 2008).

Soybean expansion also has indirect negative impacts in South America, through displacing cattle ranching into formerly forested areas. Beef production through cattle ranching is now responsible for 20% of deforestation in the continent: over 10 million hectares of forest have been cut down for this purpose in the last decade, and nearly 80% of land deforested in the Amazon between 1996 and 2006 is now used for cattle pasture (Verweij et al. 2009). Brazil, again, is the major producer, exporting US$4 bil­lion worth of beef a year—more than any other country—of which a third is consumed by the European Union (EU) (Mardas et al. 2009).


One of the reasons for the recent surge in soybean expansion in Brazil has been a shift from soybean to corn production in the USA (Butler 2007a, 2007b). This has been driven by policies promoting biofuels, including a target of reducing gasoline use by 20% through the use of corn ethanol in fuels (Searchinger et al. 2008). As a consequence, the US Department of Agriculture is considering allowing landowners currently enrolled in the “Conservation Reserve Program”—under which farmers are paid to leave land fallow, benefiting waterbirds and other species that live on grass-covered wetlands (Westcott 2007)—to terminate their contracts early for the stated purpose of “providing more acreage to meet the demand for corn” (Ducks Unlimited 2007). In the prairies of North and South Dakota, this would impact species such as Sedge Wren (Cistothorus platensis) and Bobolink (Dolichonyx oryzivorus), leading to declines of up to 52% and 39% respectively, and a combined loss of over 1·8 million individuals of five grassland passerines (Niemuth et al. 2007), many of which are already declining rapidly across North America (Butcher & Niven 2007). This highlights the importance of the Conservation Reserve Program, and the danger of converting the land it protects to corn production.

Agricultural intensification in Europe

In Europe, the principal threat to birds in the wider countryside is the intensification of farming, particularly in the EU where the Common Agricultural Policy (CAP) applies. Intensive farming driven by CAP subsidies has produced food surpluses and negative environmental consequences, as illustrated by the 48% fall in the Wild Bird Index for farmland species referred to earlier. The biggest declines in farmland birds are directly related to intensive agricultural practices: 30% of the variance in these declines across countries in Europe can be explained solely by national differences in cereal yield (Donald et al. 2001, 2006). Few birds can breed in the monocultures that are now typical of north-west Europe, and other wildlife species are likely to have suffered similarly (Stanners & Bourdeau 1995). Birds outside the EU in central and eastern Europe have fared better until recently (Fig. 23), mainly because agriculture has remained less intensive and less environmentally destructive. Without CAP reform, the twelve countries that have joined the EU since 2004 now face subsidised agricultural intensification and similar declines in their farmland birds.

The EU has also operated a similar scheme to the US Conservation Reserve Program referred to above. “Set-aside”, as it is known, was introduced in 1992 to reduce the size of Europe’s grain surpluses. It was not intended as an environmental measure, but it provided significant environmental benefits such as valuable food and nesting sites for many farmland bird species. For example, Little Bustard (Tetrax tetrax) NT has been driven extinct by agricultural intensification in at least eleven European countries, and the remaining population in France—which has crashed by over 90% in the last 20 years—now largely depends on set-aside for its survival (Wolff et al. 2001, BirdLife International 2006a). Similarly, 80% of Eurasian Linnets (Carduelis cannabina) in East Anglia, UK, spend the winter on set-aside, compared to 1% that winter on cereals (Cook 2008).

In 2007, owing to increasing demand for cereal crops and biofuels, the European Commission suspended set-aside, and from 2009 abolished it completely; but the environmental measures proposed by the Commission are woefully inadequate to compensate for the loss of valuable habitats. As a result, much set-aside land has been cultivated, once again reducing habitat availability for many farmland birds. In the UK, the area of temporary fallow land fell by 83% between 2007 and 2008 (DEFRA 2009), and a 30% reduction in set-aside land is expected (Cook 2008).


Coffee, the world’s most exported product after crude oil (O’Brien & Kinnaird 2003), is cultivated in two main ways. In traditional “shade coffee” plantations, the plants are grown under rainforest trees. This disrupts the natural understorey, but allows some forest birds and other biodiversity to survive within the complex vegetation structure. By contrast, intensive “sun coffee” plantations support many fewer species. For example, in the Cordillera Central of the Dominican Republic, bird diversity in intensive full-sun coffee plantations is less than half that found in traditional coffee plantations, shaded by native Inga vera trees (Fig. 24; Wunderle & Latta 1996). This and many other studies have demonstrated that forest bird communities are depleted when shade-coffee systems are converted to full-sun farming (Donald 2004), and the results are consistent across a wide range of other wildlife groups (Gallina et al. 1996, Perfecto et al. 1996, Wunderle & Latta 1996). Some guilds of birds are especially sensitive: nectar-feeders dependent on forest flowers are largely eliminated from intensive coffee plantations. Conversion from shade to full-sun systems clearly reduces the value of plantations for forest bird communities. Nevertheless, even shade-coffee plantations cannot substitute for pristine forests, despite their relatively biodiverse habitat matrix: many forest specialists survive poorly in shade-coffee plantations (Donald 2004). Levels of species richness within coffee plantations are also highly dependent on their proximity of natural forests: in one study, the diversity of restricted-range birds was found to decline along a gradient away from remaining intact forest by 43% within just 8 km (Anand et al. 2008).


Cocoa is also a major agricultural export commodity, with 60% of the global production coming from West Africa (Donald 2004). Global demand grew 3% a year over the twentieth century, and cocoa production is likely to remain a major driver of tropical deforestation, as demand is expected to more than double by 2050 (Bisseleua et al. 2009). As with coffee, forest birds are threatened by both the intensification of existing production methods and the conversion of intact forest to plantations. At present, around 70% of world demand is met from small-scale farmers operating traditional, low-intensity agroforestry systems (Donald 2004). Typically, cocoa crops are grown beneath thinned primary forest or under a canopy of artificially planted trees, thereby providing a structurally complex habitat capable of sustaining a far higher array of organisms than other agricultural landscapes such as oil palm plantations or cattle pastures (Faria et al. 2006). However, several studies in Latin America have shown that while shade cocoa supports large numbers of woodland generalist and migratory species, it is of limited value for specialist forest-interior birds (Greenberg et al. 2000, Reitsma et al. 2001, Faria et al. 2006). Despite the limitations of shade-growth systems, the current trend towards eliminating shade cover in order to increase yield is alarming. Landscapes dominated by full-sun monocultures support depauperate biological communities and may experience impaired ecosystem functioning. In Malaysia, the conversion to full-sun production left many cocoa crops susceptible to disease, which eventually caused the country’s cocoa industry to collapse (Donald 2004).

Oil palm

Palm oil, alongside soya, is the most lucrative commodity produced on deforested land. It is used in an extraordinary variety of foods and cosmetics, including, for example, 43 of the 100 best-selling branded products in British supermarkets in 2008 (Hickman 2009). Oil palm cultivation, already a massive industry, is expanding further (as with soya) through the demand for biofuels. The combined global demand for palm oil is expected to double by 2020 (e.g. Clay 2004, Green et al. 2005). In Melanesia and South-East Asia, the spread of oil palm plantations has been the most significant driver of deforestation in recent years. In Malaysia, for example, the area of oil palm plantations increased by over 70% between 1994 and 2004 (Clay 2004), and Malaysia and Indonesia now produce more than 80% of the world’s palm oil. Expansion of oil palm in other regions, particularly West Africa, is also a cause for concern.

Conversion of tropical lowland forest to oil palm poses a significant threat to birds and other biodiversity, because the majority of forest species cannot survive in such monocultures. One study in Thailand found that bird species diversity was 60% lower in oil palm and rubber plantations than in lowland forest areas (Fig. 25; Aratrakorn et al. 2006). Almost all species of conservation concern (15 of the 16 globally threatened or NT species recorded in forested areas) disappeared after the land was converted to plantations. Species with more specialised dietary requirements (e.g. insectivores and frugivores) suffered greater losses than more generalist consumers (omnivores), evidently owing to a reduction in food availability. Another study in Sumatra found that less than 10% of the original primary forest bird species remained in oil palm plantations (Danielson & Heegaard 1995).

On the island of New Britain off New Guinea, 12% (3000 km2) of the island’s forest was cleared between 1989 and 2000, principally for commercial oil palm plantations. Lowland forest was most affected, with nearly 25% of forest below 100 m disappearing during the period. At current rates, all forest below 200 m will be gone by 2060 (Buchanan et al. 2008). None of the island’s 37 restricted-range or endemic species are supported by oil palm monocultures. Four of them, including Russet Hawk-owl (Ninox odiosa) VU and Bismarck Kingfisher (Alcedo websteri) VU are now suspected to be declining at rates exceeding 30% over three generations. Consequently, the total number of endemic or restricted-range species classified as globally threatened or NT on New Britain owing to population declines from forest clearance recently increased from 12 to 21 (Buchanan et al. 2008).

Unsustainable forestry

Forests, particularly in the tropics, support the majority of the world’s biodiversity, including nearly two-thirds of all bird species. Deforestation has many interconnected drivers, as described above, but commercial logging is a key factor. The global trade in tropical timber is valued at about US$16 billion annually (Rytkönen 2003), with about half exported to China for manufacture of furniture, flooring and paper, much of which is re-exported (DFID 2007). The majority of this timber is harvested illegally and/or unsustainably. For example, less than 5% of wood consumed in Europe is from certified sources (Mardas et al. 2009).

Asian forests in particular have suffered from unsustainable forestry, with 3% of humid tropical forest lost in the region during 2000–2005 alone (Hansen et al. 2008). In South-East Asia, there is so little primary forest left that many forests will be logged for the second or third time in the near future, while in Sabah and Peninsular Malaysia there is virtually no primary rainforest left outside protected areas. In Indonesia, remaining forests are being rapidly cleared for timber and wood-pulp (c. 40 million cubic metres per year: FWI & GFW 2002), and the land is then converted to other uses such as oil palm (see above). Indonesia’s production capacity for wood-pulp and paper has grown by 700% since the late 1980s—mainly through illegal logging and land clearance—and is at a level that cannot be met by any form of sustainable forest management (Bryant et al. 1997). More than half of all Indonesian timber produced during 2003–2006 was logged illegally (Human Rights Watch 2009), while elsewhere in the region virtually all timber removed from forest in Laos in recent years was illegal (EIA & Telepak 2008).

Across the tropics, such practices are leaving previously continuous tracts of forest fragmented into habitat islands, scattered across an agricultural landscape (Schelhas & Greenberg 1996). Such extensive habitat loss, degradation and fragmentation has serious consequences for birds, with small islands of habitat eventually losing many of their forest-dependent species, as noted above. Selective logging is substantially less damaging to biodiversity than intensive timber extraction or clear-felling, but it also leads to reductions in diversity and abundance of forest bird species. A review of several studies shows that abundance drops by c. 30% in selectively logged forests (Johns 1988, Marsden 1998, Thiollay 1992, 1997, Felton et al. 2008) with forest-dependent birds in particular becoming rare. In contrast, birds adapted to open or degraded habitats are able to colonise selectively logged forest. Guilds differ in their responses to logging, with declines greatest in terrestrial, understorey and insectivorous species (Fig. 26; Thiollay 1997, Fimbel et al. 2001, Lambert & Collar 2002, Felton et al. 2008). For example, in Neotropical forests, terrestrial insectivores such as leaftossers (Sclerurus spp.) and ant-thrushes (Formicarius spp.) are most sensitive (Fimbel et al. 2001).

Invasive alien species and disease

Invasive alien species (IAS) are a substantial threat to the world’s avifauna, impacting 422 threatened birds (34% of the total). The problem is especially acute on islands, particularly oceanic ones (where it affects 75% of threatened species), as discussed above. Overall, alien invasive mammals are the biggest problem (impacting 340 species: 81% of those threatened by IAS), with plants (109 species, 26%), birds (78 species, 18%) and disease/micro-organisms (75 species, 18%) of lesser significance (Fig. 27). Among invasive mammals, carnivores impact 295 (70% of IAS-affected bird species, with domestic cat being the most important), rodents (particularly black rat Rattus rattus) impacting 273 species (65%), and ungulates (particularly domestic pig) 142 species (34%). Among other classes, Common Myna (Acridotheres tristis) is the most problematic invasive bird, brown tree snake (Boiga irregularis) the most significant reptile, and avian malaria (Plasmodium relictum) and avian pox (Poxvirus avium) the worst diseases. These affect threatened birds in different ways (Fig. 28), but the most significant impacts are reduced reproductive success, usually through predation of eggs or chicks (276 species, 65%), direct mortality by predators (affecting 265 species, 63%), habitat degradation by invasive herbivores and/or invasive plants (188 species, 45%), and competition for food and nest sites (63 species, 15%).

The threat from IAS is likely to rise, as people travel more, global trade expands and ongoing habitat degradation and fragmentation make it easier for aliens to establish populations. Climate change is also expected to make the problem significantly worse; for example increasing temperatures enable disease-carrying mosquitoes to spread (see below). Notably, IAS have been the primary driver of known bird extinctions, in combination with overexploitation and habitat loss driven by logging and agriculture (Fig. 29). IAS are associated with the extinction of at least 71 species, with rats, cats and introduced pathogens being the most deadly (contributing to the loss of 41, 34 and 16 species respectively).

Three examples demonstrate the seriousness of the challenge posed by IAS. In Ecuador, the Galapagos Petrel (Pterodroma phaeopygia) CR has undergone an extremely rapid decline since the early 1980s, owing in particular to predation by introduced rats, cats and dogs, and the destruction of breeding habitat by introduced goats and cattle. These invasives will need to be eradicated or effectively controlled to allow the petrel to survive. Meanwhile, on Gough Island in the South Atlantic, seabird populations are being devastated by house mice (Mus musculus) which, since their colonisation following a shipwreck, have rapidly evolved body sizes and behaviours that mimic rats (and which will be just as difficult to eradicate): almost the entire world populations of Tristan Albatross (Diomedea dabbenena) CR and Atlantic Petrel (Pterodroma incerta) VU breed on Gough, but c. 60% of chicks die before fledging owing to mice predation (Cuthbert et al. 2006, Wanless et al. 2007), causing disastrous declines in these long-lived, slow-reproducing species, and also resulting in an endemic landbird—Gough Bunting (Rowettia goughensis)—being listed as CR. Finally, over half of the 100 or so endemic bird taxa in Hawaii have been driven extinct by introduced predators, disease and habitat loss, and many of the remainder are highly threatened by IAS (Olson & James 1982, La Pointe 2000): for forest-dwelling native birds such as Palila (Loxioides bailleui) CR, the accidental introduction of mosquitoes (Culex quinquefasciatus), bringing with them avian malaria and avian pox, has had devastating consequences (La Pointe 2000, Jarvi et al. 2001, van Riper & Scott 2001).

Introduced avian malaria and avian pox are just two examples of bird diseases that can cause chronic population declines, dramatic die-offs, and reductions in the reproductive success and survival of individuals, threatening many of the world’s bird species. Certain avian diseases appear to be spreading to populations previously unaffected:

•  Avian botulism is arguably the most important bacterial disease of migratory birds worldwide. In 2002–2003, an outbreak in Taiwan killed over 7% of the world population of Black-faced Spoonbill (Platalea minor) EN (Yu 2003), while the disease is suspected to have been the cause of death in over 160 Laysan Ducks (Anas laysanensis) CR on Midway Atoll, Hawaii, USA, in 2009, representing a 40–50% decline in this translocated population (M. Reynolds in litt. 2008).

•  West Nile Virus, a mosquito-borne viral disease which kills both birds and people, has recently spread through eastern USA, Latin America and the Caribbean. American Crow (Corvus brachyrhynchos) has shown very high levels of mortality from this disease but remains relatively stable across its range (Peterson et al. 2004, Caffrey et al. 2005), while Yellow-billed Magpie (Pica nuttalli) has undergone a recent rapid (but hopefully temporary) population crash (Crosbie et al. 2008).

•  Avian cholera and Erysipelothrix rhusiopathiae, two bacterial diseases, have caused considerable declines in Indian Yellow-nosed Albatross (Thalassarche carteri) EN on Amsterdam Island (French Southern Territories). Both diseases may threaten nearby colonies of Sooty Albatross (Phoebetria fusca) EN and Amsterdam Albatross (Diomedea amsterdamensis) CR (Weimerskirch 2004). Avian cholera also threatens Cape Cormorant (Phalacrocorax capensis) NT in South Africa, e.g. killing c. 13,000 individuals in 2002 (Williams & Ward 2002).

•  Mycoplasmal conjunctivitis, an infectious disease, has recently caused a significant decline in the introduced population of House Finch (Carpodacus mexicanus) in eastern North America, and has started to spread to native populations of this species.

•  High Pathogenicity Avian Influenza (HPAI) is a poultry disease that evolved from a milder virus in wild birds. A particularly virulent strain—H5N1—recently caused devastating impacts on poultry flocks, and some human fatalities (Thomas 2005, Werner & Harder 2006, WHO 2008). H5N1 can also kill wild birds, but its direct impacts have usually been very low (although an outbreak at Qinghai Lake, China, killed c. 6000 waterbirds in 2005: Chen et al. 2005). Evidence to date suggests that the role of infected migratory birds in spreading the disease is insignificant compared to the poultry trade. However, media hysteria and public misunderstanding have led to wild migratory birds being blamed and persecuted, e.g. through culling and nest-destruction (FAO 2005, Feare & Yasué 2006, Sims & Narrod 2008). These measures put wild birds and other biodiversity in jeopardy, while being ineffective in preventing the spread of the disease.

Over-exploitation of species

Unsustainable exploitation of species is a significant threat to the world’s birds, either through hunting and trapping (principally for the cagebird trade and for food and sport), incidental mortality as bycatch in fisheries, or over-exploitation of prey species (particularly in the marine environment).

Hunting and trade

Birds are used extensively by people. A recent study found evidence of use for 4561 bird species, representing 46% of the world’s birds (Butchart 2008). Two purposes dominate: 87% of utilised species (3968) are used as pets, and 34% (1550)—although this is likely to be an underestimate—are hunted or trapped for food. Birds are also hunted for sport, used in traditional medicine, and exploited for apparel and ornamentation. The total numbers of individuals used in these different ways are unknown, but likely to be substantial. The number of individual birds sold in international trade at the start of the 1990s was estimated to be c. 2–5 million per year, and the number of individual birds taken each year for international trade at that time may have been up to 10 million—because up to half the birds could have died before they reached a dealer (Mulliken et al. 1992). The numbers taken and sold in domestic trade are unknown, but are probably on a similar scale. In terms of hunting for sport and food, Hirschfeld & Heyd (2005) estimated that over 100 million individuals of 82 bird species listed on Annex II of the EU Birds Directive were killed in the EU during 2001–2003 alone, and Magnin (1991) estimated that a staggering 0·5–1 billion songbirds are killed annually in Europe, roughly equating to one for every person alive in Europe—each year!

For many species, such levels of use are unsustainable. Some 50 bird species that were driven extinct since 1500 (one third of the total) were subject to overharvesting, including Great Auk (Pinguinus impennis) (EX since c. 1852) and Carolina Parakeet (Conuropsis carolinensis) (EX 1918). Currently, 422 globally threatened bird species (34%) are affected by overexploitation for human use. These impacts are biased towards large species (for food) and colourful and/or vocal species (as cagebirds), and hence are particularly severe for certain families, notably parrots, pigeons and pheasants (Fig. 30). Overexploitation appears to be a particular problem in Asia (Fig. 31).

Hunting is a particular concern for certain threatened bird species. For example, in August 2009 one of the last five known wild Northern Bald Ibises (Geronticus eremita) CR in the Middle East was found to have been shot (BirdLife International 2009a), and hunting on its migration route may prove to be the single most important threat to Sociable Lapwing (Vanellus gregarius) CR. Recent evidence gathered in early 2010 suggested that the Spoon-billed Sandpiper might be suffering serious losses on its winter mudflats in Myanmar (Burma), where villagers net waders indiscriminately for food (Zöckler et al. 2010).

Red List Indices (RLIs) showing trends over time in the status of utilised species indicate that such birds, overall, deteriorated in status during 1988–2004 (Butchart 2008). Although some of these species were downlisted to lower categories of threat owing to successful conservation action (e.g. Lear’s Macaw Anodorhynchus leari CR to EN), many more were uplisted to higher categories owing to increased threats and worsening status (e.g. Yellow-crested Cockatoo Cacatua sulphurea EN to CR). A combination of factors drove these trends, but hunting and trade together were the most important driver after agriculture and aquaculture.

Commercial fisheries

Across the world, commercial fisheries have expanded dramatically since the 1960s, in both intensity and extent. Commercial longline and trawl fisheries are responsible for the incidental deaths of hundreds of thousands of seabirds each year, threatening 34 species, especially albatrosses. Seabirds are particularly vulnerable to bycatch in areas where foraging concentrations overlap with high densities of commercial longline fishery vessels. Since the 1990s, scientists have been attaching remote tracking devices to albatrosses and petrels around the world in order to understand better where they forage. The results show that albatrosses travel hundreds of  kilometres per day in search of food, and that they concentrate in foraging hotspots, many of which overlap with longline fishing effort (Fig. 32; BirdLife International 2004c). These are areas where there is the highest risk of seabird bycatch, and where mitigation efforts are most urgently needed. Even a partial overlap in fishing and foraging areas is significant, because small increases in mortality can have severe effects on long-lived seabirds. For example, at Bird Island (South Georgia), long-term monitoring and demographic studies have revealed steady declines of 2–4% per year over the last few decades for Wandering Albatross, Grey-headed Albatross (Thalassarche chrysostoma) VU and Black-browed Albatross (Thalassarche melanophrys) EN, driven by reduced survival (Fig. 33). These apparently modest annual declines are highly significant for long-lived, slowly reproducing species. With long generation lengths (up to 30 years), the declines are sufficient to qualify these species as threatened with extinction.

Trawl fisheries also threaten seabirds. For example, in the South African hake trawl fishery, 18,000 seabirds were estimated to have been killed in 2005–2006 (Watkins et al. 2008). It is estimated that 85% of birds were killed by the warp cables that attach the trawl net to the fishing vessel, entangling individuals and dragging them under the water. The remaining 15% died entangled in nets. Of the birds killed, 70% were White-capped Albatross (Thalassarche steadi) NT and Black-browed Albatross, 14% were Cape Gannet (Morus capensis) NT and 9% White-chinned Petrel (Procellaria aequinoctialis) NT.

Indirect impacts through prey species

As populations of larger fish species decline throughout the world’s oceans, fisheries are increasingly targeting species that occupy a lower trophic level in the food web. This can have severe implications for the food supplies of many seabirds, as illustrated by declines in the Black-legged Kittiwake (Rissa tridactyla) population breeding on the Isle of May, UK. Overfishing of cod, mackerel and herring in the North Sea is thought to have relaxed the pressure on one of the Black-legged Kittiwake’s prey species—the lesser sandeel (Ammodytes marinus)—causing it to increase in abundance in the 1950s. Consequently a major fishery developed for sandeel (for processing into fish meal and oil). Catches near the Isle of May peaked at 100,000 tonnes in 1993, almost certainly depleting the local sandeel supply for seabirds. The Black-legged Kittiwake population declined sharply, owing to poor breeding success and reduced adult survival. By 2000, sandeel fishing was finally banned around the island, but sandeel shortages have continued, thought to be caused by climate change disrupting the plankton community at the base of the food chain (Frederiksen et al. 2004, Daunt et al. 2008). This example of a fishery targeting a small fish species reflects global fisheries trends, with short-lived fish that occupy lower trophic levels substituting for depleted stocks of long-lived predatory fish (Pauly et al. 1998, Pauly & Watson 2005). Similarly, invertebrates such as Antarctic krill (Euphausia superba) in the Southern Ocean are now being exploited, with potential implications for penguins and other seabirds (Croxall & Nicol 2004, Kock et al. 2007).

Residential and commercial infrastructure development

Ongoing infrastructure development, including residential and commercial growth, energy production, mining and transport, is a significant threat to the world’s birds (Fig. 34), and one that is likely to increase. Over 70% of the world’s land surface is predicted to be impacted by infrastructure development by 2032, particularly in Latin America, the Caribbean and the Asia-Pacific region (UNEP 2002). Unless this expansion is better controlled and planned, substantial environmental problems will affect food production, freshwater resources and health, as well as biodiversity. For birds, the most significant threat comes from the residential and commercial growth that characterises urbanisation, which is affecting 245 species (20% of threatened birds), although mining and quarrying (156 species, 13%) and roads and railroads (134 species, 11%) are also important. Urban development is occurring most rapidly in Asia (Choi 2008), and as a consequence this region holds 111 species threatened by this factor (34% of all species so affected). For example, the major wintering area for Relict Gull (Larus relictus) VU at Bothai Bay, China, has been encroached by reclamation for oilfields, harbours, roads and other developments, and there are plans to reclaim 43% of the remaining habitat (Yang Liu et al. 2006). In South Korea, reclamation of 400 km2 of coastal mudflats at Saemangeum for a golf complex in 2006 (following abandonment of initial plans to use the land for rice farming) seems likely to have caused a 20% decline in the world population of Great Knot (Calidris tenuirostris) since then (D. Rogers in litt. 2009). In Australia, urban encroachment into Swift Parrot (Lathamus discolor) EN breeding and foraging areas is a major threat because the species seems particularly susceptible to collisions with fences, windows and cars (Saunders & Tzaros 2009).

Powerlines, masts and wind-farms

Telecommunications towers (for radio, television and mobile phones), energy powerlines and buildings are a real danger to birds, killing astonishingly large numbers through collisions each year (Shire et al. 2000). One study suggested that 4–5 million birds are killed in the USA each year by collisions with towers (USFWS 2002), but in reality the annual total may reach as high as 40 million (Longcore et al. 2005). In Wisconsin, a single radio tower caused at least 120,000 bird deaths during 1957–1995 (Kemper 1996), and there are at least 100,000 large towers of this sort in the USA alone (Evans & Manville 2000).

Powerlines can cause bird mortality through electrocution as well as collision. Electrocution generally affects large species such as owls and diurnal raptors, while collision mainly affects nocturnal migrants and species with low flight manoeuvrability (such as bustards, swans, storks, cranes and herons).

Examples of significant mortality of birds caused by powerlines include:

•  In Spain, 30% of juvenile Spanish Imperial Eagles (Aquila adalberti) VU are electrocuted on powerlines each year (Janss & Ferrer 2001).

•  In Kazakhstan, a single 100-km section of powerline in Atyrau caused at least 311 raptor electrocutions in a single year, while no fewer than 932 Steppe Eagles (Aquila nipalensis) were electrocuted in one season along 1500 km of powerline north of the Caspian Sea (Moseikin 2003). Given that Russia and Kazakhstan hold at least 50,000–70,000 km of this type of powerline, this pressure alone may explain a large proportion of the raptor declines reported in this region.

•  In Italy, at least 95 bird species suffer mortality from powerlines (Rubolini et al. 2005), with up to 87 dead birds per km of powerline per year (Fig. 35).

•  In Hungary, over 30,000 birds are killed by powerlines and pylons every year. Raptors are among the most affected, including Saker Falcon (Falco cherrug) VU and Eastern Imperial Eagle (Aquila heliaca) VU. It is estimated that every year one in seven pylons kills a bird and one in eighteen kills a raptor (Demeter et al. 2004, BirdLife International 2008c).

•  In South Africa, powerlines cause 1·25 collisions per km per year of Ludwig’s Bustard (Neotis ludwigii) EN, equating to over 8200 casualties annually—a rate that demographic models indicate is not sustainable (Jenkins et al. 2010).

•  In Wyoming, USA, 232 Golden Eagles (Aquila chrysaetos) and other migrants were killed on powerlines during 2007–2009 (costing PacificCorp US$1·4 million in fines and $9·1 million to make the powerlines safer: American Bird Conservancy 2010a).

Windfarms are an important source of green energy, but when sited without consideration for biodiversity they can cause significant mortality of birds through collisions, as well as disrupting movements between feeding, wintering, breeding and moulting areas. Birds do not seem to habituate or adjust behaviourally to windfarms in order to avoid the danger of collision: in fact, the longer windfarms are in operation, the worse the decline of certain bird species appears to become (Stewart et al. 2005). High-profile examples include the Smøla islands off the north-west Norwegian coast, where windfarms have killed several White-tailed Eagles (Haliaeetus albicilla) and caused the failure of almost 30 others to return to nesting sites; as the site is remote, other deaths may have gone undetected (BirdLife International 2006b). In Navarra, Spain, a single windfarm was estimated to kill eight Griffon Vultures (Gyps fulvus) per turbine per year (out of 22 birds of all species per turbine per year: Lekuona 2001), and windfarms have been shown to cause long-term population declines in Spanish Egyptian Vultures (Neophron percnopterus) EN (Carrete et al. 2009). At Cape Kaliakra in Bulgaria, windfarm developments threaten half a million soaring birds (including pelicans, cranes, buzzards, eagles and storks) that migrate along Europe’s second-largest soaring bird migration route (BirdLife International 2005), while proposed windfarms in Wyoming, USA, threaten Greater Sage-grouse (Centrocercus urophasianus) NT (American Bird Conservancy 2009a).

Changes in fire regimes

In rainforest, fires are naturally very rare, so birds and other biodiversity suffer substantially when human-initiated fires occur. Many bird species cannot survive in extensively burnt forest. For example, the population density of hornbills decreased by 28–63% in fire-damaged forest in Bukit Barisan Selatan National Park, Sumatra, because of the sparse canopy and scarcity of fruit (Anggraini et al. 2000). Burnt forest may take hundreds or even thousands of years to return to its original state (Chambers et al. 1998). Human activity increases the risk of fire and its negative impacts in several ways. Fragmentation of forests increases their edge-to-area ratio, making them less humid and more susceptible to fire. Roads allow access to areas previously protected by their remoteness. Fires from slash-and-burn cultivation often spread into areas of primary forest. Smouldering underground coal seams or layers of peat burn for years, re-igniting fires during the dry season: in 2003 as many as 1000 underground coal fires were burning in Indonesia alone (Bhattacharya 2003). Forest fires also cause substantial carbon emissions, contributing to climate change (see below): the 1997 fires in Borneo and Sumatra, Indonesia, destroyed 50,000 km2 of forest (an area larger than Switzerland) and released as much carbon into the atmosphere as Europe emits from fossil fuel combustion in a year (Liew et al. 1998, Page et al. 2002).

In Australia, the landscape and wildlife have been moulded by human-induced fire since pre-history. However, in order to provide grazing, clear land or demonstrate ownership, Europeans burned habitats more frequently, destructively and extensively than Aborigines did traditionally. These changes in fire regime were a major factor in the extinction of at least five bird taxa (Gill et al. 1999). Today, inappropriate fire regimes remain a considerable threat to Australia’s threatened birds, particularly those of heathlands and savanna (Garnett & Crowley 2000, Olsen 2008). For example, Mallee Emuwren (Stipiturus mallee) EN requires heathlands unaffected by fires for at least ten years. At Ngarkat Conservation Park, 40% of the heathland in 1990 had been burned within the previous decade and was consequently unsuitable for the species. By 2006, further fires had rendered over 65% of the area unsuitable and the Mallee Emuwren population had declined by 80% (Paton & Rogers 2008). Noisy Scrub-bird (Atrichornis clamosus) VU is another good example, avoiding areas that are burnt more often than about every six years, and reaching highest densities only after 20–25 years of vegetation regrowth, so more frequent fires cause long-term declines (Fig. 36; Smith 1985). Since 2001, an increase in the number of wildfires has further reduced the species’ breeding habitat within Western Australia (Tiller & Danks 2008).

Inappropriate water management

Wetlands—rivers, lakes, lagoons and marshes—are critical for biodiversity, including 12% of all threatened birds. Wetlands also provide a wide range of benefits and services for people’s livelihoods and wellbeing, such as food, fibre, flood protection, water purification, cultural values and of course water supply. However, wetlands across the world are under a range of threats, including: drainage for agricultural or commercial development; damming, canalisation and other channel management practices that change flow regimes; and over-extraction of water that reduces river flow and causes lakes to shrink.

Large dams produce major ecological changes in river basins, destroying forests and other habitats, altering natural flooding regimes, and causing the loss of aquatic biodiversity both upstream and downstream, with impacts on water quality and species composition. Dams have significantly fragmented a high proportion (61%) of the world’s river basins (World Commission on Dams 2000). In Africa, the Middle East and Europe, dams and other hydrological structures are judged to pose a threat to nearly 10% (304) of the 3701 IBAs in this region. Most of these sites (87%, 264) qualify as wetlands of international importance under the Ramsar Convention (Fig. 37). In Asia, actual or planned dam projects are likely to have significant impacts on at least ten globally threatened birds. Riverine waterbirds, especially those that nest on sand-bars, such as Indian Skimmer (Rynchops albicollis) VU, are affected particularly badly. Such species typically have very linear ranges, occupying a small area in total. They are therefore particularly susceptible to threats that may have consequences throughout their range. Canalisation also causes damaging changes in flow patterns. For example, the Danube Delta on the border of Romania and Ukraine is internationally important for more than 20,000 pairs of breeding waterbirds, and, in winter, up to 7% of the world population of Red-breasted Goose (Branta ruficollis) EN. However, it is now threatened by the construction of a 170 km long deep-water channel for shipping, which will have serious environmental impacts on the delta’s wetlands (BirdLife International 2004d, 2009b).

Marshes, swamps and bogs are particularly susceptible to drainage, either to convert the habitat to use for agriculture or development, or as a by-product of over-extraction of water. For example, drainage of Iraq’s Mesopotamian marshes (in combination with upstream dams and other developments) reduced the extent of the marshes by 90% between the 1950s and 2000, leading to the uplisting of Basra Reed-warbler (Acrocephalus griseldis) to EN. Fortunately, improved management and conservation efforts are now reversing the situation, with up to 39% of the marshes reflooded by 2005, but the future availability of water for restoration is in question and only a fraction of the former marshes may recover (Richardson & Hussain 2006).


Pollution, in various forms, has direct and indirect negative impacts on birds, causing problems for at least 170 threatened species. Pollutants cause direct mortality, reduced reproductive success and indirect impacts through habitat degradation. The major pollutants are effluents from agriculture (in particular, pesticides), forestry, industry and oil spills (Fig. 38), but “pollution” of the night skies by lights affects a smaller number of threatened species, including Newell’s Shearwater (Puffinus newelli) EN and Barau’s Petrel (Pterodroma baraui) EN, which return to their colonies after dark and become disorientated by artificial lights. Similarly, radiation can be a problem in specific circumstances: Barn Swallows (Hirundo rustica) around Chernobyl (the site of the world’s worst nuclear accident in 1986) show increased genetic mutations and lower reproductive success and survival, and populations of a number of species in the area are probably only sustained by immigration (Møller & Mousseau 2006).

Agricultural pollution

While they are useful for food production and disease control, pesticides have substantial negative environmental impacts. One estimate suggests that, in the USA alone, 672 million birds are exposed each year to farmland pesticides, and 10% die as a result (Williams 1997). Monocrotophos, an organophosphate insecticide used in crop farming, is particularly toxic. Over 100,000 avian mortalities have been documented since the 1960s, including the mass poisoning of nearly 6000 Swainson’s Hawks (Buteo swainsoni) in Argentina during 1995–1996 (Goldstein et al. 1999). Similarly, in Mongolia, 3500 km² of steppe were treated with the rodenticide bromadiolone, following a population explosion of voles. Even without systematic monitoring, over 340 dead or dying birds were seen at several localities, including 145 Demoiselle Cranes (Grus virgo) (Natsagdorj & Batbayar 2002), with the full scale of the impacts doubtless being much larger. In the African Sahel region, 13 million hectares were sprayed with organophosphorus insecticides during the last major desert locust (Schistocerca gregaria) outbreak in 2003–2005, which is likely to have had substantial, but undocumented, impacts on birds (Mineau 2009). Although levels of DDT and its metabolites in Osprey (Pandion haliaetus) eggs in Chesapeake Bay, USA, in 2009 were at less than half the levels reported in the 1960s–1970s, total organochlorine concentrations have declined only marginally (American Bird Conservancy 2010b).

Deliberate use of  poison, with birds as the intended or incidental victims, is a common phenomenon in some parts of the world, for example when farmers attempt to prevent crop damage or persecute perceived predators of small livestock by lacing carcasses with toxic chemicals such as the carbamate pesticide, methomyl (Mineau et al. 1999). In two recent incidents in Botswana, over 80 individual vultures—including White-backed (Gyps africanus) NT and Hooded Vulture (Necrosyrtes monachus)—were deliberately poisoned by poachers in an attempt to eliminate vultures in the area, as protected area authorities quickly detect poaching activities through vulture concentrations at kills (BirdLife International 2009c). Similarly, in the Bunyala area of western Kenya, the pesticide carburofan is used to kill thousands of birds per month to sell for human consumption, despite the toxicity of the poison to humans too (BirdLife International 2009c).

Diclofenac is a non-steroidal anti-inflammatory drug used to treat livestock, but unexpectedly it has proved highly toxic to vultures that feed on the carcasses of animals recently treated with it (Oaks et al. 2004, Shultz et al. 2004). In South Asia species such as White-rumped Vulture (Gyps bengalensis) CR, once one of the most abundant large raptors in the world, have declined in numbers by over 99% since the early 1990s (Prakash et al. 2007). Modelling shows that even a rate of one contaminated carcass in every 130–760 is sufficient to account for the population crash (Green et al. 2004). Alarmingly, a second drug, ketoprofen, has recently also been found to be toxic to vultures; one in 200 carcasses in southern Asia contains the drug, and in 70% of these the levels are potentially lethal (Naidoo et al. 2010).

Lead-shot and land-based waste

Lead in shotgun pellets is intended to kill birds on impact, but because it is highly toxic and slow to break down, it has the unintended effect of killing birds many decades after its use. Every year, lead poisoning causes the deaths of many hundreds of thousands of waterbirds, which mistake spent pellets for food or for the grit they need to aid digestion. Up to 40% of all waterbirds in Europe and North Africa ingest at least one lead pellet per year: enough to kill a bird or increase its susceptibility to predation, starvation or disease (Beintema 2001, Fisher et al. 2006). Lead poisoning from hunted game is a threat to humans, too: c. 15% of waterbirds of species regularly eaten by people have lead levels in their blood well above those considered safe for human consumption (Beintema 2001).

Terrestrial birds are also affected: at least 59 such species are known to have been poisoned by ingesting lead shot, nine of which are threatened or NT (Beintema 2001, Fisher et al. 2006). In particular, scavengers and raptors are exposed to lead in dead animals or discarded offal. Lead ingestion accounts for up to 15% of post-fledging mortality in Bald Eagle (Haliaeetus leucocephalus) in North America (Beintema 2001) and remains the primary threat to California Condor (Gymnogyps californianus) CR, while Spanish Imperial Eagles are exposed to shot embedded in Greylag Geese (Anser anser), the primary prey in winter and a heavily hunted species (Pain et al. 2005a).

Raptors are also susceptible to other forms of anthropogenic pollution because they seek out bone fragments and small indigestible items in order to acquire calcium and help regurgitate food pellets. Increasingly, they also ingest toxic or sharp debris dumped by humans, and this can poison or choke them, and block or penetrate their guts. Nestlings are particularly at risk because they are less able to regurgitate indigestible items (Ferro 2000). Low breeding success in Griffon Vultures in Israel and Armenia has been linked to nestlings dying after eating metal objects (Ferro 2000). Similarly, six of eight California Condor nestlings that died or were removed from the wild had swallowed substantial quantities of glass shards, metal bottle-tops, ammunition cartridges, electrical wiring, plastic piping and rubber items. Two were found to have ingested their own body weight in such items. Most showed retarded feather development as a result of malnutrition resulting from blocked digestive systems, and one suffered from zinc poisoning (Mee et al. 2007).

Marine pollution and anthropogenic debris

Oil spills at sea are the most dramatic form of marine pollution, killing large numbers of seabirds and potentially wiping out entire populations where these are small or localised. The wreck of the Prestige tanker off north-west Spain in November 2002 oiled up to 230,000 individual seabirds (García et al. 2003), and almost drove extinct the Iberian breeding population of Common Murre (Uria aalge) (now reduced to a handful of individuals at a single colony at Cabo Vilán: P. Arcos in litt. 2009). The Deepwater Horizon oil spill in the Gulf of Mexico off the coast of Louisiana, USA, in April 2010 had become the largest in US history at the time of writing, threatening at least ten IBAs (American Bird Conservancy 2010c). African Penguin (Spheniscus demersus) VU is particularly at risk from spills, as over 80% of its population breeds within 100 km of a major harbour, and the world’s largest oil-shipping lane lies offshore of the entire breeding range. Wrecks in 1994 and 1998 led to the oiling of 10,000 and 20,000 penguins respectively. In addition, over 2% of these birds are oiled each year from smaller, unreported spillages and illegal discharges during tank-cleaning operations.

Other forms of marine pollution are less visually striking but with a much more widespread impact. For example, on average over 13,000 pieces of plastic float on every square kilometre of ocean (Derraik 2002, UNEP 2005). Entering the sea via offshore dumping, beaches and rivers, this debris reaches the remotest parts of the ocean and affects over 44% of seabird species through entanglement and ingestion (Laist 1997). Seabirds often mistake floating plastic items for prey, and ingest them. Remarkably, about 80% of large pieces of plastic washed ashore on beaches in the Netherlands show peck marks from birds at sea (Cadée 2002, Derraik 2002). Ingested plastic is ubiquitous in some seabird species: 95% of Great Shearwaters (Puffinus gravis) and 93% of Blue Petrels (Halobaena caerulea) have plastic in their digestive systems (Ryan 1987, Moser & Lee 1992), and plastic, nylon, rubber and metal have been found in 36% of Northern Fulmars (Fulmarus glacialis) and 29% of Black-browed Albatrosses (Mallory et al. 2006, Petry et al. 2007). Such debris is regurgitated to feed chicks, and can obstruct and physically damage a bird’s digestive system, leading to malnutrition, starvation and death: 98% of nestling Laysan Albatross (Phoebastria immutabilis) VU and 73% of Southern Giant-petrel (Macronectes giganteus) have been fed debris including beads, buttons, cigarette lighters, toys, golf tees, rubber gloves, marker pens, aluminium foil and lightbulbs (Auman et al. 1997, Copello & Quintana 2003). Toxic chemicals called polychlorinated biphenyls (PCBs) also become concentrated on the surface of plastics at sea and are released when seabirds ingest them, with serious detrimental effects on reproduction, immune system and hormone balance (Derraik 2002). Some seabirds face the double whammy of marine and terrestrial pollution. For example, Laysan Albatrosses also suffer from lead poisoning from paint chips off abandoned military buildings on Midway Atoll, Hawaii, with up to 10,000 chicks per year being affected (Finkelstein et al. 2010).

Persistent organic pollutants and acid rain

Industrial chemicals like PCBs, residues of organochlorine pesticides like DDT, and unwanted by-products such as dioxins are collectively known as persistent organic pollutants (POPs). These toxins persist in the environment, and are now found almost everywhere, in terrestrial, freshwater and marine ecosystems. They concentrate in fatty tissues in organisms, and dramatically increase in concentration as they move up the food chain. POPs are linked to reproductive failure, deformities and physiological and behavioural dysfunctions in wildlife. In the heavily polluted Great Lakes region of the USA, predators such as Bald Eagle and Double-crested Cormorant (Phalacrocorax auritus) have suffered significant health impacts from POPs including eggshell thinning, deformities, cancers, hormone system dysfunction and immune suppression (Orris et al. 2000). Despite bans in many countries, these chemicals are still used in medicine, industry and agriculture around the world.

Similarly ubiquitous, sulphur and nitrogen pollution from vehicles, heating, power-plants, factories and agriculture can be transported large distances in the atmosphere before falling as acid rain and causing problems for terrestrial and freshwater habitats in particular. This has major economic impacts on forestry, agriculture and human health, as well as driving bird population declines through eggshell thinning. Long-term acid deposition depletes calcium in acid-sensitive soils, reducing the quality of eggshells and lowering reproductive success. In the UK, eggshell thickness has declined over the past 150 years in at least four species of thrush Turdus spp. owing to acid deposition (Green 1998), and acid rain has been implicated in population declines of several bird species breeding in the eastern USA (including Bicknell’s Thrush Catharus bicknelli VU), particularly in high-elevation areas with low pH soils (Hames et al. 2002).

Climate change

Human-induced climate change, caused by greenhouse gas emissions resulting from fossil fuel burning and deforestation in particular, is now well established. Increasing temperatures, sea-level rises and shifts in precipitation patterns and snow cover are projected to continue at an unprecedented rate. If so, and if left unaddressed, these phenomena will inevitably have sweeping and dramatic effects on biodiversity. Although these may be positive for some species, e.g. Common Eiders (Somateria mollissima) in south-west Iceland appear to be benefiting from climate change (D’Alba et al. 2010), they are likely to be negative for the great majority of species, through impacts on their distribution, abundance and behaviour, and through changes in community composition and structure. Such impacts are already being felt: two recent meta-analyses examining more than 100 studies and over 1000 species have shown that over 80% of shifts in range or phenology (timing of biological events) have been in the direction expected from climate change, giving us a very high confidence that climate change is already impacting biodiversity (Parmesan & Yohe 2003, Root et al. 2003).

Documented impacts on birds

Over 400 bird species have already been documented as having experienced climate-driven impacts to date (BirdLife International unpublished data). Changes in migration times have been widely recorded. In Europe, migrants from sub-Saharan Africa have arrived 2·5 days earlier on average in the last 40 years, possibly so that they can cross the Sahel before the seasonal dry period. By contrast, migrants wintering north of the Sahara have delayed autumn passage by 3·4 days on average over the same period (Jenni & Kéry 2003). Similarly, in New York and Massachusetts, USA, migrants wintering in the southern USA arrived 13 days earlier on average in 1993 compared with 1951, while those wintering in South America arrived four days earlier (Butler 2003). In the southern hemisphere, migrants have arrived in south-east Australia 3·5 days earlier per decade on average since 1960, while departure dates have been delayed by 5·1 days per decade on average (Beaumont et al. 2006).

Some species have shown changes in timing of breeding: 63% of 65 breeding species in the UK nested earlier by 1995 compared to 1971, by nine days on average (Crick et al. 1997). Others, however, have not, and this causes them problems. Thus, the food supply for Great Tit (Parus major) chicks in the UK now peaks earlier owing to changes in vegetation phenology driven by increasing spring temperatures; but egg-laying by the tits has not advanced, presumably because the cues to which tits respond have not shifted in synchrony, so there is now a mismatch between food supply and timing of breeding (Visser et al. 1998). In some European Pied Flycatcher (Ficedula hypoleuca) populations in the Netherlands, such mismatches have driven population declines of c. 90% over two decades (Both et al. 2006). Similarly, short-distance (but not long-distance) migratory hosts of the brood-parasitic Common Cuckoo (Cuculus canorus) have advanced their arrival dates more than the cuckoo, and this mismatch may be contributing to the decline of cuckoo populations (Saino et al. 2009).

The altitudinal and latitudinal boundaries of species’ ranges are also in flux (Fig. 39). Between 1979 and 1998, lowland and foothill species such as Keel-billed Toucan (Ramphastos sulfuratus) extended their ranges up mountain slopes in Costa Rica in response to elevated cloud-base levels (Pounds et al. 1999). Breeding birds in southern Finland extended their ranges north by an average of 19 km between 1974–1979 and 1986–1989 (Brommer 2004). In North America, the northern limit of 26 southerly species shifted 61 km northwards between 1971 and 1998 (Hitch & Leberg 2007), the winter distributions of 254 species shifted 44 km north during 1975–2004 (La Sorte & Thompson 2007), and the wintering ranges of landbirds in general shifted over 70 km north during 1966–2005 (Niven et al. 2009). In the southern hemisphere, too, species such as Pacific Baza (Aviceda subcristata) and Pied Butcherbird (Cracticus nigrogularis) in Australia have undergone significant southward range expansions (up to 200–300 km) since the late 1970s (Silcocks & Sanderson 2007), while White-throated Eared-nightjar (Eurostopodus mystacalis), which once moved north during the cooler months, now overwinters in south-eastern Queensland (Chambers 2007).

Climate change has had an increasing impact on bird population trends in Europe since about 1990, as shown by the Climatic Impact Index (Fig. 40). This shows that species expected to gain range in response to climatic change (based on climate envelope modelling) show positive population trends (based on systematic monitoring), and those expected to lose range in response to climatic change show negative trends (Gregory et al. 2009). Significantly, there have been three times as many declining species as the number benefiting from climate change. Among 100 European bird populations, declines during 1990–2000 were more likely for species that had not advanced their spring migration, presumably owing to mismatches mentioned above between breeding and food supply (Møller et al. 2008). These trophic mismatches may have been a major cause of population collapse in long-distance migrants in highly seasonal habitats in the Netherlands during 1984–2004 (Both et al. 2010).

For Australian seabirds the responses have also been mixed: breeding colonies along the Great Barrier Reef have suffered major declines linked to rising sea temperature and increasingly intense El Niño events, while temperate populations of species like Australasian Gannet (Morus serrator) in the Bass Straits have experienced considerable increases (Devney & Congdon 2007). More localised population changes include 90% declines in just seven years (1987–1994) in numbers of Sooty Shearwaters (Puffinus griseus) NT found off the western USA in the non-breeding season (attributed to changes in ocean surface temperatures and ocean currents associated with climate change: Veit et al. 1997).

Such distribution and population density changes alter bird community composition. In Germany, one study showed that, at a local scale, the proportion of long-distance migrant species decreased and the number and proportion of short-distance migrant and resident species increased between 1980 and 1992, possibly because higher winter temperatures benefit residents and intensify the competitive pressure on long-distance migrants (Lemoine & Böhning-Gaese 2003). In France, a 91 km northward shift in bird community composition (measured as the balance between low- and high-temperature dwelling species) was recorded between 1989 and 2006, a period during which the temperature increase corresponded to a 273 km northward shift. Birds are thus lagging c. 180 km behind climate warming (Devictor et al. 2008), and it might be expected that other less-mobile organisms are experiencing even more serious mismatches, although the evidence for this is not yet clear (Hickling et al. 2006).

Projected impacts on birds

Modelling studies indicate that the impacts documented to date are likely to be typical of the effects expected. Much research has focused on projecting how the combination of climatic conditions found in species’ present ranges will change in future. This shows that while some species may benefit from climate change, many more are predicted to suffer because the area of suitable conditions for them will contract and/or shift too fast. One study showed that the breeding ranges of European species are projected to shift north-eastwards by 260–880 km depending on the emission scenario (Fig. 41; Huntley et al. 2007, 2008). On average, future ranges are expected to be 20% smaller than they are now, and to shift substantially, overlapping by only c. 40% with present breeding distributions. Species that are likely to experience both a substantial proportional range loss and shift, such as Marmora’s Warbler (Sylvia sarda), are of particular concern (Fig. 42; Huntley et al. 2007, 2008). Another study in sub-Saharan Africa showed that the median degree of overlap between current and projected ranges in 2085 for 815 species of conservation concern is just 31·5%, but with substantial regional variation (Hole et al. 2009). At individual sites, average turnover in species composition is projected to be 10–13% by 2025 and 20–26% by 2085 (and 18–21% increasing to 35–45% by 2085 for species of conservation concern: Hole et al. 2009).

These range-shifts and other impacts will cause problems for migrants (Newson et al. 2008), especially those that have intercontinental migrations. By the end of the century, over half of all trans-Saharan migrant warblers will face longer migrations, some by over 250 km (Doswald et al. 2009).

The impacts of climate change will be particularly severe at the poles, parts of which are the fastest warming regions on earth (ACIA 2004, Turner et al. 2005). In the Antarctic, rising temperatures are likely to have profound implications for the sea-ice dynamics that govern the region’s ecosystems. Retreating sea-ice has already been linked to declines in Antarctic krill, the backbone of the Antarctic food chain and a key prey species for many seabirds (Moline et al. 2004, Gross 2005). Particularly vulnerable are Emperor Penguin (Aptenodytes forsteri) and Adelie Penguin (Pygoscelis adeliae), both of which depend on pack-ice throughout their life cycles. A global mean temperature rise to 2°C above pre-industrial levels (projected to occur within 40 years) will render 50% of existing Emperor colonies and 75% of Adelie colonies unviable (Ainley et al. 2008). Population modelling for one Emperor Penguin colony at Terre Adélie projects a precipitous decline, with a 36% probability of extinction by 2100 (Jenouvrier et al. 2009). The contraction of sea-ice will have similarly negative consequences for Arctic wildlife. For example, Ivory Gull (Pagophila eburnea) NT is largely restricted to pack-ice when feeding. The Canadian breeding population of these gulls is already thought to have declined by 80% since the early 1980s (Gilchrist & Mallory 2005).

Bird species at the polar edges of continents will have limited opportunities for dispersing to new areas of suitable habitat, and will be among the hardest-hit by climate change. A study of 23 Arctic waterbird species showed that, on average, they may lose 35–51% of their breeding range by 2080 (Zöckler & Lysenko 2000): Dunlin (Calidris alpina) could forfeit up to 58% of its breeding habitat in this time-frame, and Red-breasted Goose up to 85% (Zöckler 1998). Another study of 27 northern landbirds in Fennoscandia projected range reductions of 74–84% by 2080 (Virkkala et al. 2008).

Mountain-top species have similarly restricted opportunities to disperse as unsuitable conditions move upslope. In north-east Queensland, Australia, the distributional extents of 13 bird species endemic to montane tropical rainforests are expected to shrink dramatically as suitable climate space retreats to higher altitudes: range sizes will reduce by 30% on average with a 1°C temperature increase, and 96% with a 3·5°C rise (Fig. 43; Houghton et al. 2001, Williams et al. 2003).

Sea-level rise is projected to reduce or eliminate available habitat on low-lying islands and coasts. Species restricted to such situations, such as Cozumel Thrasher (Toxostoma guttatum) CR and wintering Orange-bellied Parrot (Neophema chrysogaster) CR will thus have their survival prospects further reduced (Bennett et al. 2007). Bermuda Petrel (Pterodroma cahow) EN is already suffering from wave damage to nesting sites during increasingly frequent and severe hurricanes (Madeiros 2008), and increased frequency of typhoons may be an important threat to breeding sites of Chinese Crested Tern (Sterna bernsteini) CR (Chen et al. 2009, Chan et al. 2010). Relatively few studies have examined this issue across suites of species, but Legra et al. (2008) found that at least eleven of New Guinea’s endemic bird species could lose over 10% of their current range if sea-levels rise 1 m, with White-bellied Pitohui (Pitohui incertus) NT projected to lose 41% of its range under these circumstances.

Climate change is also likely to exacerbate other threats, such as habitat loss and invasive species. The anticipated sea-level rises will result in mass human migration and greater dependence on adjacent lands and resources, inevitably leading to major habitat conversion and the depletion and loss of many associated bird populations. In Australia, eucalypt woodlands are likely to suffer directly from increased fire frequency, and indirectly through the consequent spread of fire-adapted weeds such as gamba grass (Andropogon gayanus), which in turn promotes further fires. Modelling shows that this invasive species from Africa could become established across much of northern Australia, further threatening birds such as Gouldian Finch (Erythrura gouldiae) EN (Low 2007). In Hawaii, climate change may exacerbate threats from introduced avian pox and malaria, transmitted by introduced mosquitoes (see page 27 above). These are restricted to the lowlands, so cooler high-elevation forests remain the last refuge for 18 threatened bird species (mainly Hawaiian honeycreepers Drepanididae). Climate change is predicted to lead to a lifting of the cloud-base, and consequent upward shifts of montane cloudforests (Still et al. 1999) and hence the zone of malaria risk. The results of modelling this phenomenon for three critical protected areas on the islands of Hawaii, Maui and Kauai show alarming increases in the areas of high malaria risk, and reductions or disappearances of areas with low risk (Fig. 44; Benning et al. 2002): a temperature increase of 2ºC will almost eliminate low malaria-risk forest in the Hakalau Wildlife Refuge on Hawaii (an important area for five threatened bird species). As the cloudforest zone is constrained in its upward shift because of previous clearance for pasture at higher elevations, reforestation above the reserve will be crucial to improving the endemic species’ chances of survival. (In addition, modelling shows that control of introduced rats Rattus spp. at mid-elevations would facilitate the spread of malaria resistance in several native species: Kilpatrick 2005.)

A common theme across these examples is that the degree of global warming will determine the size of the extinction crisis caused by climate change. Some extinctions will probably result if global average temperatures rise by 2°C, but there will be some practical management options for conservation. However, both biodiversity and people will face a bleak future if temperatures rise significantly higher (IPCC 2007).

Underlying drivers

There are a number of drivers behind these threats to birds and biodiversity. Most importantly, our economic systems currently fail to account for the substantial value of nature, instead favouring short-term benefits from converting intact habitats to human uses. On average, half of the total economic value of natural habitat is lost following its wholesale appropriation for a more intense human use. Habitat conversion does not make long-term economic sense; indeed, the benefits of conserving remaining natural habitats appear to exceed the costs by at least 100 to 1 (Balmford et al. 2002). However, conversion is often also encouraged by policies that introduce economically perverse incentives for environmentally damaging activities such as over-fishing and wholesale deforestation. One reason for this is that it is difficult to agree on values for things that are not traded, or whose benefits lie in the future. Economies therefore ignore the value of goods and services derived from natural ecosystems (including climate regulation, soil fertility, crop pollination and water purification), even though one estimate puts it as high as US$33 trillion per year (Costanza et al. 1997) and another estimates that the value of services from terrestrial ecosystems lost each year is c. US$70 billion (TEEB 2008).

A good example of the important contribution birds make to such services comes from a study in the Serengeti, Tanzania. This showed that when fire disturbance opens up the canopy of riverine forest, frugivorous birds decline, reducing the proportion of tree seeds digested by birds. As undigested seeds are more vulnerable to attack by beetles, seed germination rates, seedling density and tree recruitment rates all fall, leading to forest loss: 70–80% of riverine forest patches have been lost since 1950. Birds therefore play a key role in maintaining the forest, and their loss leads to its conversion to savanna (Sharam et al. 2009). Of more direct economic consequence, birds play a critical role in pollination, seed dispersal, control of insect and rodent pests, and carrion removal, as Sekercioglu (2006) pointed out in the Foreword to HBW 11. Examples include:

•  Avian control of spruce budworm in spruce plantations in Washington State, USA, is estimated to be worth at least US$1500 per km2 annually (Takekawa & Garton 1984).

•  Pest control by birds in Canada’s boreal forests was estimated to be worth C$5·4 bil­lion in 2002 (Anielski & Wilson 2009).

•  Predation of insect pests by birds in apple plantations in the Netherlands increases yields by two-thirds (Mols & Visser 2002).

•  Avian control of the coffee berry borer (Hypothenemus hampei) on coffee farms in Jamaica has been estimated to be worth US$310 per ha (Johnson et al. 2010).

•  Birds are important for pollination of at least 50 crop and medicinal plant species (Nabhan & Buchmann 1997).

•  Gyps vultures in India play (or played) an economically important role in scavenging of animal carcasses. Their precipitous loss has led to increases in the feral dog population, with one (admittedly controversial) study estimating there have been 47,000 additional human deaths from rabies, at a cost to the Indian economy of US$34 billion (Markandya et al. 2008).

•  Birds may also play a significant role in regulating some diseases. In the USA, a recent study showed that more diverse bird communities can reduce, through a dilution effect, the incidence in humans of West Nile virus. The virus has caused over 1100 human deaths, and associated healthcare costs were estimated at US$200 million for 2002 alone (Swaddle & Calos 2008).

Failure to incorporate the value of nature into economics is exacerbated by global imbalances in power and wealth. Poor people are often the most directly dependent on natural resources. For example, 1·4 billion people depend on forests for their livelihoods and food security (World Bank 2004). However, the poor are often compelled for their short-term survival to use natural resources unsustainably. They are often excluded from decision-making, denied their human and political rights, and displaced by commercial developers, agribusiness, political instability or insecurity. Vulnerable populations are forced to migrate, intensifying poverty, increasing conflict over land use, and placing further pressures on natural habitats. In such circumstances, they may be forced to use whatever resources they can, even in areas set aside for biodiversity protection.

Growing human populations and individual consumption levels are fundamental drivers of threats to biodiversity. When the first volume of HBW was published in 1992, the world population was just below 5·5 billion. By the time the series is completed in 2011, it will have reached 7 billion (UN 2008). In the time it takes to read this Foreword, the equivalent of a small town of 10,000 people will have been added to the world population. Unfortunately, the areas with the fastest-growing populations often coincide with areas of unique biodiversity. In sub-Saharan Africa, human population density is positively correlated with species richness of terrestrial vertebrates (Balmford et al. 2001), and similar congruence between the distributions of people and biodiversity have been found in Australia (Luck et al. 2004), North America (Luck et al. 2004), Europe (Araújo 2003) and within the tropical Andes (Fjeldså & Rahbek 1998).

However, in terms of human impacts on the planet, the growth in consumption is of more immediate concern than the alarming growth in population itself. In recent decades most of the latter has occurred in poorer parts of the world, where each individual consumes fewer resources. For example, the per capita “ecological footprint” (i.e. the area with globally averaged productivity required to produce the resources consumed by each individual) is 0·8 ha in India compared to 4·5 ha in Europe and 9 ha in the USA. In total, humans now consume each year 1·5 times as many resources as the planet can generate sustainably in a year, and this demand has grown by 71% since 1970 (www.footprintnetwork.org). Nevertheless, while current levels of global consumption derive largely from developed countries, the world’s poor will place increasing demands on our planet in future, as countries develop and prosperity rises. For example, as developing nations become wealthier they eat more meat and dairy products. The per capita consumption of pork in China has almost doubled since 1990 (from 20 to 40 kg), and China is now the world’s biggest importer of soy to feed its growing livestock sector. Similarly, increasing dairy consumption in India and the corresponding need for feedstock is challenging the country’s ability to sustain soy exports (Mardas et al. 2009). Consequently, for example, the increasing wealth of both China and India is directly driving pressures on forests and cerrado in South America.

What can we do?

Despite the depressingly poor state of the world’s birds, and the multiplicity of threats and their magnitude reviewed above, there is a suite of conservation approaches available to tackle the current crisis that can and do work, provided sufficient resources and political will are applied. These include identifying, protecting and managing key sites (IBAs), combined with tackling threats at the broad scale (through appropriate legislation and land-use planning that takes biodiversity into account). Where these site-focused and landscape- or seascape-scale approaches are insufficient in the short-term (most often the case for species on the brink of extinction), species-specific research and interventions will also be needed.

Site protection

Protecting key places for biodiversity has been a cornerstone of conservation efforts for over a century. Tackling threats and implementing solutions is often most tractable at the site scale.

For birds, the Important Bird Area (IBA) approach to identifying priority sites using globally standardised criteria has been developed and implemented by BirdLife International since the 1980s. IBAs are identified using objective criteria based on the presence of species of global conservation concern, assemblages of restricted-range (see Stattersfield et al. 1998) and biome-restricted species, and large concentrations of congregatory species. IBAs are also effective at capturing other terrestrial biodiversity (e.g. Brooks et al. 2001, Eken et al. 2004, Pain et al. 2005b, Langhammer et al. 2007), so are an excellent first cut for the larger set of Key Biodiversity Areas—an extension of the IBA approach to other taxa. Wherever possible, IBAs are identified and documented at the national level through a multi-stakeholder process. To date over 10,000 IBAs of global significance have been identified in 206 countries (Fig. 45). Typically, IBA identification is followed by conservation planning, action on the ground, advocacy, capacity-building and monitoring.

Increasingly, IBAs are being recognised by governments as priorities for formal protection by designation as national parks, reserves, sanctuaries and other types of protected area (indeed, many sites were already officially protected when they were identified as IBAs). However, there is still a long way to go: the mean percentage IBA area protected has increased to 39%, while the percentage of IBAs that are completely protected has risen to 26% (Fig. 46). For both metrics, the rate of increase appears to have levelled off since the late 1990s, perhaps partly because the easiest sites to designate have been protected first, but also because of delays in information flow.

As well as national legislation, there are three global initiatives to promote the conservation and management of important sites: the Ramsar Convention on Wetlands, the World Heritage Convention and UNESCO’s Man and the Biosphere Programme. Although many IBAs qualify under the criteria of these initiatives, only a minority have been designated to date (e.g. Fig. 47). The situation is similar for regional conventions, such as the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) under the Convention on Migratory Species (CMS). Although at least 2252 IBAs support globally significant numbers of one or more of the AEWA-listed species, nearly 40% of these sites still lack protection.

In the EU, the Birds Directive requires all member states to create and properly manage a coherent network of Special Protection Areas (SPAs) for bird taxa of conservation concern. IBA identification criteria are deliberately aligned with SPA selection criteria, so the European Commission and Court of Justice have recognised national IBA inventories as “shadow lists” of SPAs. This has helped to increase the designation (partial or entire) of IBAs as SPAs from 23% to 64% during 1993–2008, despite growing numbers of IBAs and member states over this period (Fig. 48). However, over 1000 European IBAs still do not overlap with any SPA, and are therefore urgent priorities for designation. There is good evidence that such designation benefits the targeted species: Donald et al. (2007) found a significant positive correlation between the percentage of land area designated as SPAs in the original 15 member states and the mean population trends of bird species of conservation concern (those listed on Annex 1 of the Birds Directive: Fig. 49).

Similar evidence for the value of formal protection comes from monitoring IBAs in Kenya. IBA indices (which summarise data collected using BirdLife’s standard IBA monitoring protocols) show that, compared to non-protected sites, IBAs with formal protection are in better condition, and have marginally lower pressures and better conservation responses in place, including better management planning and implementation (Fig. 50; Mwangi et al. 2010).

While formal protection of IBAs is often preferable, other approaches can also be effective. These include establishing community management of resources, ensuring that effective safeguard policies are applied, and securing thorough environmental impact assessments for development projects. In all cases, success requires long-term commitment and local community and stakeholder involvement.

Managing sites

Managing IBAs often involves identifying which of the suite of threats outlined above impact the species for which the IBA is designated, and then tackling these with targeted interventions at the particular site. Site management commonly involves managing habitats to benefit particular species or suites of species. For example, Kirtland’s Warbler (Dendroica kirtlandii) NT has strict requirements for breeding habitat, namely stands of young (5–23 year old) jack pine (Pinus banksiana) growing on well-drained soils. By 1971, the warbler population had declined to just 201 singing males confined to a small area in the Lower Peninsula region of Michigan, USA. Active habitat management then began, including clearing and replanting large areas of jack pine each year, and managing the fire regime. In combination with control of the brood-parasitic Brown-headed Cowbird (Molothrus ater), this has allowed the warbler population to increase to 1792 individuals by 2008, and to spread to Wisconsin and Ontario (Fig. 51; Probst et al. 2003). Habitat restoration, or even creation of new areas of habitat, can have dramatic effects. Within a year of the creation in 2006 of an artificial island at Kamfers Dam, South Africa, Lesser Flamingos (Phoeniconaias minor) NT colonised the site and in 2008–2009 raised 13,000 chicks, thereby creating only the fourth breeding locality in Africa and the sixth in the world (Anderson 2008, M. D. Anderson in litt. 2009).

Efforts to make forestry practices more sustainable, and to improve farming practices so as to reduce threats to forests, are common priorities for management of tropical forest IBAs. Mount Oku in the Bamenda Highlands, Cameroon, is a critical site for a number of species endemic to the Cameroon highlands, such as Bannerman’s Turaco (Tauraco bannermani) EN and Banded Wattle-eye (Platysteira laticincta) EN. However, the site has suffered decades of forest loss and degradation. Since 1987, a community-managed project has been working with local people to establish agreed forest boundaries, implement sustainable use of forest resources and improve agricultural practices. This has resulted in the rate of forest regeneration exceeding the rate of deforestation since 1995, and the IBA is gradually improving in condition (Fig. 52; BirdLife International 2004b).

The threat from alien invasive species can be successfully reduced or even eliminated at the site scale, particularly for small islands. Clipperton Atoll, c. 1000 km off the coast of Mexico, provides a good example. Historically, it was sparsely vegetated, with extremely high densities of plant-eating land crabs (Gecarcinus planatus), and tens of thousands of nesting seabirds. However, the introduction of feral pigs in 1897 devastated the seabird populations through predation of both eggs and crabs, the latter resulting in a dramatic increase in plant cover and a concomitant reduction in seabird nesting sites (Sachet 1962). Since pigs were removed in 1958, the ecological balance has been restored and there are now an estimated 11 million land crabs, little vegetation cover (Dodson & FitzGerald 1980), and, once again, one of the largest Masked Booby (Sula dactylatra) and Brown Booby (Sula leucogaster) colonies in the world (with c. 40,000 and 20,000 birds respectively). Unfortunately, rats have recently been discovered on Clipperton, probably introduced following shipwrecks of longline shark-fishing boats in 1999 and 2001 (B. Tershy in litt. 2003). They are the next target for eradication on the island.

Advances in technological solutions are being made in relation to the more challenging invasive alien species such as rodents. The development of advanced types of targeted poisons, and effective protocols (often involving helicopters) to distribute bait has led to numerous successful eradications from islands. Indeed, funding may now be the only limit on the size of island that can be tackled (the largest successful rat eradication to date took place in 2001 on the 113 km2 Campbell Island, New Zealand, but in 2010 the eradication of rabbits, rats and mice will commence on the 128 km2 Macquarie Island in the South Atlantic). Even when complete elimination is not practical or affordable, targeted trapping and poisoning can provide sufficient management to tip the balance towards survival for a threatened bird species.

Where unsustainable hunting is the key threat to priority species at an IBA, site management involving a combination of awareness-raising among hunting communities and strict law enforcement can produce impressive results. For example, the population of White-headed Duck (Oxyura leucocephala) EN in Spain had been reduced to just 22 birds confined to a single lagoon in Córdoba province, Andalucía, by 1977 (Green & Hughes 1996, Torres Esquivias 2003). In 1979, however, conservation management began, initially focusing on enforcing the prohibition of hunting. The population began to recover, and now numbers c. 2200 individuals (Fig. 53), with breeding in 13 provinces (Torres Esquivias 2003, Madroño et al. 2004). Effective protection from illegal hunting was undoubtedly the key factor, but habitat measures such as the removal of introduced fish, control of pollution and sedimentation, and regeneration of fringing vegetation were also significant.

Many IBAs come under pressure from commercial and infrastructure development. A soda ash extraction plant at Lake Natron, Tanzania, was approved recently after an environmental impact assessment failed to take account of the negative consequences the development would have on Lesser Flamingos, for which the site is the most important breeding colony in the world. Concerted protests by a coalition of community and environmental groups, including BirdLife partners, has at least delayed construction, but the threat remains (BirdLife International 2009d). Similarly, strong opposition succeeded in minimising the impact of a hotel development that would have destroyed or degraded a substantial proportion of the remaining habitat for Grenada Dove (Leptotila wellsi) CR on Grenada, Lesser Antilles (BirdLife International 2007a, D. C. Wege in litt. 2009). Proper assessment of the potential impacts would have precluded these plans ever getting off the drawing board.

Wetland IBAs often require actions tackling management of water supply and quality. At the Hadejia Nguru wetlands in north-east Nigeria—an important wintering site for Ferruginous Duck (Aythya nyroca) NT among other waterbirds—management is tackling the consequences of poorly regulated upstream water use, including dam construction, which has led to the spread of Typha reeds, causing choking of waterways and changes to water flows. Successful management, including channel clearance, has produced increases in both fish catches and waterbird populations (Langley 2009). In India, the formerly spectacular wetlands at Bharatpur (Keoladeo National Park) had all but dried up by 2000 following water extraction and damming upstream, leading to dwindling numbers of colonial waterbirds (such as Black-headed Ibis Threskiornis melanocephalus NT and Eurasian Spoonbill Platalea leucorodia) for which the site had been famous. Management is now underway to restore water flows into the park, including construction of a 16 km pipeline from the Goverdhan drain and the Gambhir River (Times of India 2008).

Broad-scale action

Some threats to the world’s birds require interventions at the landscape scale or through regional, national or international approaches to complement local actions and make them effective in the longer term. Thus, while it may be possible to control or eradicate invasive alien species at individual IBAs, policies and programmes to limit the spread of these aliens are essential in order to prevent further introductions. Similarly, while measures may be effective at individual sites to restrict the hunting of birds for food or the trapping of birds for pets (e.g. through nest protection, anti-poaching patrols, and education and awareness-raising with local communities), they need to be complemented by action at broader scales to reduce demand, provide more sustainable alternatives, and manage national and international trade.

Other threats to birds can only be tackled effectively at the broad scale. For example, effective national policies, land-use planning and legislation that take the needs of biodiversity into account are the primary mechanism for tackling threats from unsustainable forestry and agriculture (including the expansion of biofuels), transport development, pollution and inappropriate water resource management (e.g. through dams and drainage). International interventions are needed to minimise threats from oil spills or fisheries bycatch (much of which takes place in international waters), or for which coordinated international action is essential (e.g. climate change).

Reforming agricultural policy

The threat from continental-scale agricultural intensification necessitates broad-scale policy responses. In Europe this requires reform of the EU’s Common Agricultural Policy and greater use of agri-environment schemes (AES), under which farmers are paid to improve their land management practices to benefit biodiversity and the wider environment. Well-designed AES can deliver impressive results in reversing the decline of farmland birds and other biodiversity (e.g. Brereton et al. 2005, Knop et al. 2006, Wotton & Peach 2007). For example, the Eurasian Skylark (Alauda arvensis) declined rapidly in the UK from the mid-1970s to the mid-1980s, probably because of the change from spring to autumn sowing of cereals. This practice limits opportunities for nesting attempts later in the season, because the crop is then too tall, and diminishes overwinter survival by reducing the area of stubble (Wilson et al. 1997, Donald & Vickery 2000). Leaving small patches of bare ground (“Skylark plots”) within autumn-sown cereals provides many of the benefits of spring-sown cereals at very low cost to the farmer. Implementation of such measures as part of an AES can increase Eurasian Skylark chick productivity by 50% (Donald & Morris 2005). There are many other examples showing that wildlife-friendly measures can be integrated with profitable commercial cropping.

Promoting sustainable forestry

The sustainable use of forests requires the application of commercial forest management practices that do not harm forests of high biological value, in combination with landscape-scale planning to integrate areas for protection, rehabilitation and commercial exploitation. In the 1970s and 1980s, Costa Rica had one of the highest rates of deforestation, and forest cover dropped to just 21% by 1987 compared to 75% only 50 years earlier (Kleinn et al. 2002). However, astute government policies and incentives launched in the late 1980s to protect the remaining forest and encourage re-forestation have increased forest cover to 51% today, showing that deforestation can be reversed and forest managed sustainably. One important mechanism to achieve sustainable forest management is high-quality independent certification schemes providing eco-labelling for timber and timber products. There are a number of such schemes, but the longest running and most extensive is that operated by the Forest Stewardship Council (FSC), which covers 1·2 million km2 of forest in 82 countries (5% of the world’s productive forests), with FSC-labelled sales worth over US$20 billion in 2008 (FSC 2009).

Controlling invasive alien species and limiting their spread

While there are many examples of successful control or eradication of invasive alien species in the wild, such measures need to be complemented by effective policies to minimise the spread of aliens through customs controls and the careful regulation of shipping, air and land transport networks. While many countries (82%) have signed up to international or regional agreements that commit them to dealing with alien invasives, only 55% of all countries have relevant national legislation (McGeoch et al. 2010), and even fewer possess adequate action plans that are being effectively implemented. Key considerations here are first that the damage done by aliens can be expensive to nations in terms of resources, income and heritage by comparison with the measures needed to prevent invasion, and second that the difficulty and expense of eradicating a well-established alien is more or less in inverse proportion to the ease and costlessness with which it can be introduced, or indeed reintroduced, into an environment. The price of alien-free environments is eternal vigilance.

Minimising the impact of development projects

Threats to the world’s birds from development projects need to be addressed by mainstreaming effective policies and procedures to ensure that biodiversity concerns are incorporated into the overall planning and implementation of large-scale human enterprises such as mines, transport infrastructure, windfarms, tidal barrages, dams, power stations, power distribution systems, new towns, factories, dockyards, airports and holiday complexes. All such development projects should only be permitted after rigorous and even-handed environmental impact assessments.

Some countries have taken welcome steps to incorporate biodiversity concerns into land-use planning: Mongolia has a comprehensive strategy for mining, infrastructure and tourism development that explicitly takes account of the country’s IBAs in order to avoid detrimental impacts (BirdLife Asia 2009), and Namibia’s plans to develop uranium mining across the country are taking account of the location of IBAs and other key sites for biodiversity (BirdLife International 2010b).

Wherever possible, biodiversity impacts should be avoided or else fully mitigated; and offsets should be considered only where negative impacts are unavoidable. Windfarms, as a specific example, need to be carefully planned and designed: they should not be built near populations or movement corridors of birds of conservation importance, and are generally most safely sited relatively far offshore, away from concentrations of seaduck.

Making electricity powerlines safer for birds can only be achieved through landscape-scale action. The Hungarian Ornithological and Nature Conservation Society, working in collaboration with electricity providers and government, has developed an insulating plastic cover for the metal cross-arms of electricity poles to help minimise avian electrocutions. Over 50,000 insulators have now been fitted, significantly reducing the frequency of both electrocutions and power-cuts (Fig. 54; Bagyura et al. 2004). Electricity companies have now signed a voluntary agreement to make all dangerous powerlines more “bird-friendly” by 2020 (BirdLife International 2008c). Similarly, in Spain, simple, inexpensive alterations to the design of powerline poles can cut annual mortality of juvenile Spanish Imperial Eagles by more than 50% (Janss & Ferrer 2001), while a study of communications towers in the USA has shown that removal of non-flashing lights from towers can reduce mortality by 50–71%, as well as lowering operating costs (Gehring et al. 2009).

Addressing the bird trade

Exploitation of species for the international bird trade is managed through the Convention on International Trade in Endangered Species (CITES), which bans trade between countries for some species (listed on its Appendix I), and sets limits on numbers for others (listed on Appendix II). However, these quotas are frequently set with inadequate evidence to support the presumption that commerce is sustainable, often because of lack of capacity at the national scale. Providing far better support in such circumstances, for basic research and monitoring of population sizes, trends, levels and impacts of trade, is probably the most urgent issue that CITES needs to address. The USA and EU have banned (or very heavily restricted) the import of wild-caught birds, partly in response to concerns over the sustainability of much of this trade, although some believe that this has created new smuggling channels which will now be all the harder to control (G. Scheres verbally 2009). In Indonesia, it has been argued that the keeping of cagebirds is so ubiquitous (e.g. 57% of urban households in Java and Bali have kept a bird in the last ten years) that softer policy approaches are needed in order not merely to avoid alienating potential supporters of bird conservation but actively to enlist their backing for improved self-regulation and management. Such approaches may include market-based mechanisms, certification schemes and voluntary regulatory systems to increase the contribution of captive breeding and hence reduce the pressure from harvesting of wild birds (Jepson & Ladle 2009).

Preventing unsustainable hunting

Curbing unsustainable levels of hunting of migrant birds in Europe, particularly in the Mediterranean, requires a combination of broad-scale awareness-raising and effective enforcement. The EU Birds Directive protects these species in theory, but implementation at the national scale is often weak. In Malta, national legislation permitting the shooting and trapping of spring migrants has not been changed, so the EU has instigated legal proceedings against the state. Even where the law is brought into line with EU requirements (as in Cyprus, where in 2009 for the first time a ban was imposed on the shooting of birds in May, an important month for the passage of spring migrants), observance of laws and regulations is poor and hunters remain defiantly entrenched in their old traditions. Successful conservation requires persistence, until public and political opinion sufficiently erodes the power base of the transgressors. In some contexts, however, particularly where the situation is urgent, real results may only be achieved through working directly with hunters. In Trinidad, hunters are being recruited to raise awareness among their own communities of the vulnerability of Trinidad Piping-guan (Pipile pipile) CR to try to reduce levels of exploitation. Similarly, in North Africa and the Middle East guidelines and codes of practice to promote sustainable hunting have been produced in association with hunters as part of a region-wide integrated attempt to start to reduce the threat from excessive exploitation (BirdLife International 2010c).

Minimising fisheries bycatch

To reduce incidental mortality in longline fisheries for many of the world’s albatrosses, a suite of simple, cheap and effective mitigation measures have been developed. These can dramatically reduce the numbers of birds being killed. Studies have shown that the use of a “bird-scaring line” can reduce seabird mortality while also increasing fish catch because fewer baits are lost to birds (Brothers 1991, Løkkeborg 2001). Other effective measures include setting lines at night when birds are less active, and adding weights to lines to make them sink more rapidly out of the reach of seabirds (Robertson et al. 2006). Such measures, particularly when used in combination, can reduce seabird bycatch by 80–90%. Ensuring uptake of these measures requires communicating and demonstrating their benefits to fishermen in seabird bycatch hotspots, and working with national and regional fisheries management organisations (through which fish stocks are managed) to make these measures mandatory. While the Commission for the Conservation of Antarctic Living Marine Resources (CCAMLR) has made considerable progress (e.g. reducing albatross bycatch by over 99% around South Georgia: Croxall 2008), over 80% of global albatross distribution is outside CCAMLR waters, overlapping mainly with swordfish and tuna fisheries managed by the world’s five tuna commissions. In 2004, only one of the tuna commissions had any requirements for vessels to reduce seabird bycatch (Small 2005), but by 2008 this had increased to four (Fig. 55).

Preventing pollution

Proper enforcement of robust legislation is the primary mechanism by which to reduce the threat to birds and other biodiversity from pollution in its various forms. Crucial elements include:

1)   clean-air legislation to cut the sulphur and nitrogen pollution from vehicles, factories and agriculture that cause acid rain;

2)   banning of dangerous pesticides and other persistent organic pollutants, and the promotion of non-toxic alternatives;

3)   prohibiting the use of lead ammunition, particularly over wetlands, again with the promotion of safer alternatives;

4)   targeted measures to minimise light pollution where this is an issue; and

5)   national legislation and international agreements to promote safe tanker design and shipping routes to minimise the risk and impact of oil spills.

Localised pollution events such as oil spills require immediate and fully resourced responses to limit their impact, including the rescue, cleaning and rehabilitation of oiled birds. Encouragingly, such efforts appear to have improved over recent decades, with the proportion of rescued oiled African Penguins released back into the wild in a healthy state having increased from 55% in the 1970s to 86% in 2000, and the overall population estimated to be 19% larger now than it would have been without rehabilitation efforts (Ryan 2003). Cleaning oiled birds is expensive (e.g. nearly US$1·5 million for the Treasure disaster in South Africa in 1998: Whittington 2003), but trivial relative to the profits of the companies responsible for the pollution.

Replacing and avoiding veterinary diclofenac

To address the specific threat to vultures from diclofenac, the governments of India, Pakistan and Nepal have now passed legislation banning its manufacture (but not its sale). Efforts are now focusing on replacing diclofenac with meloxicam, an alternative not toxic to vultures (Pain et al. 2008). In India, following publicity campaigns and lobbying, the government ordered a crackdown on companies selling diclofenac in 2008. In Nepal, vultures are being provided with diclofenac-free carcasses, and diclofenac use has dropped by 90% since 2006 following the introduction of measures to reduce its application, such as exchanging it with meloxicam near breeding colonies (BirdLife International 2008d). While diclofenac is being phased out, a captive breeding programme has been established, with 283 vultures in captivity at three breeding centres in India, one in Pakistan and one in Nepal by 2009 (Bowden 2009).

Promoting international environmental agreements

Many of the broad-scale actions needed by the world’s birds require regional or international coordination. The world’s governments have now endorsed many biodiversity-relevant international agreements to achieve this: over 500 such treaties exist to date. Among the most significant for birds are the Convention on Biological Diversity, CITES, the Ramsar Convention and the CMS and its agreements (on albatrosses and petrels, and African–Eurasian waterbirds). However, many countries have failed to ratify these treaties, and the lists of species the agreements target for particular action often require updating and expanding. Arguably, non-governmental organisations make significant contributions to the efficacy of the conventions, filling gaps too often left by governmental inadequacies. Most importantly, these political agreements need to be followed up with the necessary interventions, for example by drawing up and implementing species action plans through the CMS, or protecting key waterbird sites under the Ramsar Convention.

Mitigating and adapting to climate change

The threat to the world’s birds from climate change will require global action. It is essential not just for birds but for all life on the planet that the average degree of warming is limited to 2ºC, but this will require urgent and substantial measures across multiple sectors to reduce carbon dioxide and other greenhouse gas emissions. Even if this is achieved, extensive action will still be required to help birds adapt. For example, IBAs will need to be managed adaptively and as a coherent network of sites taking consideration of the shifts in species’ ranges that are projected. A recent study estimated that by 2085 the African IBA network will retain suitable conditions for all but 7–8 “priority” species triggering IBA designation, and 88–92% of these priority species will retain suitable climate in at least one IBA in which they are currently found (Hole et al. 2009). This is good evidence that we must not give up on site-based conservation approaches just because the distribution of species and composition of communities are projected to become more dynamic. However, the considerable ­turnover in the complement of species at each site (e.g. >50% at 42% of African IBAs for priority species by 2085: Hole et al. 2009) means that it will be essential to manage IBAs in the light of these dynamics. For some sites, it will be important to promote the resilience of particular species through managing habitats to maintain their suitability as long as possible. For other IBAs, management must focus on developing suitable conditions for species expected to colonise (Hole et al. 2010). It will also be important to identify and protect new IBAs, and take action to facilitate the movement of species between sites, through maintaining or developing habitat corridors or stepping stones, and making the intervening land-use as biodiversity-friendly as possible; in extreme cases, translocation may be needed.

Potentially the most significant opportunity for broad-scale action to benefit biodiversity lies with the provision for financing forest conservation through Reducing Emissions from Deforestation and Forest Degradation (so-called “REDD”) under the United Nations Framework Convention on Climate Change. Recognising the substantial contribution that deforestation makes to greenhouse gas emissions and hence climate change, governments have agreed on the importance of establishing a finance mechanism for generating the requisite flow of resources to reduce deforestation and forest degradation. The challenge will be to design a system of payment structures to create the incentives that ensure tangible, lasting, achievable, reliable and measurable emission reductions while maintaining and improving the other ecosystem services forests provide. While the approach is not without risks for biodiversity, well-targeted REDD financing to priority conservation areas could make an immense contribution to conserving birds and other biodiversity.

Species-focused action

For some threatened species, dealing with threats at individual sites and/or broad-scale interventions in the wider environment needs to be complemented by more targeted species-specific actions. Often this starts with research to understand the causes of an observed decline and to identify specific management responses, such as the control of introduced predators or provision of nest sites. Translocations of populations or reintroductions from captivity are usually a last resort, but can be remarkably successful. In some cases, “Species Action Plans” can be an effective way of identifying the key problems and solutions, coordinating activities and ensuring acceptance by all stakeholders, although the financing of the implementation is too often a neglected or deferred element in the process.

Innovative research

Novel research techniques are rapidly improving our ability to determine the true status of species and the causes of their declines. For example, satellite-tracking is being increasingly used to reveal the distribution, movements and ecology of species. Northern Bald Ibis and Sociable Lapwing provide illuminating examples.

Until recently, the Northern Bald Ibis was believed to survive in the wild only in south-west Morocco, with an additional semi-wild population in Turkey. However, in 2002, a small colony of seven individuals was discovered at Palmyra, Syria (Anon. 2002, Serra 2003). Although the birds appeared to breed successfully, few juveniles returned each year. Satellite transmitters attached to three adults in 2006 showed that they migrated on a 6000 km round-trip across seven countries, to winter in the Ethiopian highlands. Local researchers quickly located the three tagged ibises at the wintering grounds, along with the fourth adult bird, but there was no sign of the nine younger ibises. The challenge is now to protect the birds from hunting and harmful pesticides in winter and on migration, and to track young birds to determine where they overwinter (Lindsell et al. 2009).

Sociable Lapwing breeds on the grassland steppes of Kazakhstan and south-central Russia, and migrates through the Middle East to wintering areas in Israel, Eritrea, Sudan and, on a separate trajectory, north-west India. The species has suffered a very rapid population decline in recent decades, but research suggests that factors on the breeding grounds are not solely responsible for this. So, to understand better the migration routes and threats in the non-breeding season, individuals have been fitted with satellite transmitters in Kazakhstan since 2007. The birds were tracked to Turkey, and when scientists followed the signals they found a remarkable flock of 3200 birds, the largest recorded in over a century (BirdLife International 2007b). Other birds were located over the border in Syria, where they were found to suffer intense hunting pressure. The trackers showed that the birds left these sites in late October, eventually arriving in central Sudan after a total trip of more than 8000 km (Fig. 56; Anon. 2007). The discovery of the birds’ migration route and wintering grounds is an important step towards safeguarding the species, and work to protect the stopover and wintering sites is now underway.

At sea, satellite tracking devices and geolocators are also being used to understand better the distribution of foraging seabirds, which is important for assessing where they overlap with fishing effort and hence where they might be at greatest risk from bycatch in fisheries (Fig. 32). BirdLife’s Global Procellariiform Tracking Database now holds over 5000 locality records for 28 seabird species contributed by over 60 scientists and research groups from around the world (Fig. 57), and has been an effective tool in promoting the application of mitigation measures to reduce seabird bycatch (Croxall 2008).

Other technologies are also being harnessed to support bird conservation in innovative ways. For example, while the breeding range of the Aquatic Warbler (Acrocephalus paludicola) VU in Europe is well known, the wintering grounds were until recently poorly understood. Researchers analysed feathers from birds caught in Europe to examine the patterns of isotopes, and matched these to isotope maps of West Africa (where the birds grow new feathers while moulting in winter). This narrowed the search to a zone just south of the Sahara, and an analysis of past African records in combination with modelling of potentially suitable climatic conditions led researchers to likely areas bordering the Senegal River. In 2007, fieldworkers tracked down a population of 5000–10,000 birds in the Djoudj National Park, an IBA in north-west Senegal, which it is estimated may hold up to a third of the global population. Efforts are now underway to initiate monitoring and management of the park to benefit the species.

Two other fields of research that offer promise are remote camera trapping and automated sound recording, both of which potentially allow significant scaling up of survey efforts to overcome constraints posed by the availability of skilled fieldworkers. Technological advances, reduced costs and developments in statistical analysis are leading to increased use of remotely triggered cameras for surveying large ground-dwelling birds such as cracids and pheasants (O’Brien & Kinnaird 2008). Camera traps led to the rediscovery of Sumatran Ground-cuckoo (Carpococcyx viridis) CR and the first record for over a century of Giant Pitta (Pitta caerulea) NT in Kerenci Seblat National Park, Sumatra, Indonesia (Martyr 1997, Dinata et al. 2008), and are being used to census Jerdon’s Courser (Rhinoptilus bitorquatus) CR in Andhra Pradesh, India (Jeganathan et al. 2002). Similarly, affordable devices now exist for automated recording of bird sounds, and software to detect and classify bird sounds automatically is ever-improving (Brandes 2008). Such technology has been used, albeit unsuccessfully, in the quest for convincing evidence that Ivory-billed Woodpecker (Campephilus principalis) CR survives in the USA (Fitzpatrick et al. 2005), and in surveys for seabirds and Puaiohi (Myadestes palmeri) CR on Kauai, Hawaii (American Bird Conservancy 2008a), and will no doubt become an increasingly useful tool for bird conservation research.

Species management

Once research has revealed the distribution, ecology and threats to species, intensive management—supplementary feeding, nest-site protection or provision, brood mani­pulation, control of invasive alien species, translocation, and/or captive breeding and reintroduction—may be required. Often a combination of techniques is used.

Seychelles Magpie-robin (Copsychus sechellarum) was reduced to just 12–15 birds on a single island by 1965 owing to a mixture of threats. In 1994, following some crucially important ecological research and a series of management experiments (Watson et al. 1992), a full recovery programme was initiated, involving habitat creation, supplementary feeding, nest defence, provision of nestboxes, control of introduced species and translocations to other islands (Bristol et al. 2005). As a consequence, the population now numbers at least 178 birds on four islands (Fig. 58) and the species has been downlisted from CR to EN. Similarly, the population of Mauritius Parakeet (Psittacula eques) was reduced to fewer than a dozen birds in 1986, including just three females (Thorsen & Jones 1998). The replacement of upland dwarf forest with plantations had left the population confined to a tiny remnant of native forest covering just 50 km2. A recovery programme was initiated, including captive breeding, brood manipulation (e.g. movement of chicks from large broods to foster parents), provision of artificial nest cavities, and control of alien invasive predators and competitors such as crab-eating macaque (Macaca fascicularis) and black rat. By 2007, this had increased the wild population to over 340 birds and again the species was downlisted from CR to EN.


Some threatened bird species have declined so severely that large parts of their historical range are no longer occupied. Even when the threats that led to such declines have been adequately mitigated, recolonisation of formerly occupied areas may not occur naturally. In such cases, and in particular for species on islands, it may be appropriate to translocate individuals in order to re-establish populations.

The breeding grounds of Bermuda Petrel were unknown until 18 pairs were found in 1951 nesting on a group of tiny rocky islets in Bermuda. Provision of artificial burrows and baffles fitted to natural burrows to exclude White-tailed Tropicbird (Phaethon lepturus) (the petrel’s principal nest-site competitor) allowed the population to increase to 70 pairs by 2003 (Madeiros 2003). However, the breeding sites are highly susceptible to wave damage during hurricanes, so a second population has been established on the nearby island of Nonsuch, which is larger, higher and better protected from hurricanes and rising sea-levels. Since 2004, over 100 chicks have been moved to the new colony, and in 2008, the first birds returned to the island. Hopes are high that within the next few years they will start to breed on the island for the first time in nearly 400 years (Madeiros 2008). Similarly, a programme began in 2008 to translocate Short-tailed Albatross (Phoebastria albatrus) VU chicks from their current stronghold on Torishima Island, Japan, to the site of a former colony at Mukojima in the Bonin Islands, 350 km to the south-east. Currently, 80–85% of the world population breeds on the outwash plain from an active volcano and hence are highly vulnerable (BirdLife International 2008e). The establishment of a further population would substantially improve the survival prospects of this species.

Rimatara Lorikeet (Vini kuhlii) EN was until recently confined to the tiny (9 km2) island of Rimatara in French Polynesia, plus two sites in the northern Line Islands of Kiribati, where the species had been introduced in historical times. The Rimatara population would be highly vulnerable if black rats were to be accidentally introduced, an event which is feared to be inevitable. Consequently, it was decided to establish a second population on Atiu in the southern Cook Islands (McCormack 2006), where the species had occurred until driven extinct two centuries previously by exploitation for feathers to decorate ceremonial headdresses. In 2007, 27 birds were translocated to Atiu, and the first breeding was reported in 2008, with some birds having already spread to the neighbouring island of Miti’aro, and the total population on Atiu numbering 40 birds by October 2009 (BirdLife International 2008f, G. McCormack in litt. 2009).

Captive breeding and reintroduction

For some species, the balance between rate of decline, size of population, intensity of threats and time required to mitigate them is such that it becomes appropriate (or even essential) to take some or all of the remaining birds into captivity. This is followed by a carefully managed programme of “conservation breeding”, threat control and reintroduction. California Condor provides one of the best examples. Lead shot ingested from game carcasses unretrieved by hunters was responsible for the long-term reproductive failure of the species and a seemingly ineluctable decline in its numbers, so that by 1985 just nine individuals were left in the wild. The remaining birds were brought into captivity and integrated into a captive population by 1987. By 1992, the first captive-born juveniles were released in California, followed by releases in Arizona (1996) and Baja California, Mexico (2002) (Cade et al. 2004, Wallace 2005). There are now over 150 birds in the wild, but just seven wild chicks have fledged and no second-generation birds have yet matured. Released birds continued to suffer high mortality rates (Meretsky et al. 2000), primarily owing to lead poisoning, despite the banning of lead ammunition within the condors’ range. Much work remains before the population can be regarded as self-sustaining, but the species would certainly have disappeared without intensive intervention.

Success stories

Other examples exist of birds brought back from the brink by concerted action involving measures described above. Black Robin (Petroica traversi) EN from the Chatham Islands, New Zealand, had declined to just three males and two females by 1980 owing to predation by introduced rats and cats, and deforestation. Nest protection, supplementary feeding, a cross-fostering programme (with the congeneric Tomtit P. macrocephala) and translocation from Mangere Island to South East Island successfully increased the population to around 250 birds by the late 1990s (Fig. 58). Although only 180 were estimated in 2007, it is uncertain whether this is a consequence of changing survey techniques or climatic impacts on productivity (D. Houston in litt. 2007). Similarly, Rarotonga Monarch (Pomarea dimidiata) EN was formerly common, but had declined to 38 birds on Rarotonga (Cook Islands) by 1987 (Robertson et al. 1994). Recovery work commenced in 1988, including intensive control of predators (particularly black rats) to reduce adult mortality and increase nesting success. By 2006, the population had reached 291 individuals (Fig. 58), including an introduced population of 36 individuals on the rat-free island of Atiu (200 km north-east of Rarotonga: Robertson & Saul 2007).

A critical measure of conservation success is whether conservation action has prevented any extinctions. One recent study (Butchart et al. 2006b) estimated that 16 bird species would have gone extinct during 1994–2004 were it not for conservation programmes that addressed their threats, reduced rates of population decline and/or increased population sizes. The mean minimum population size of the suite of species increased from 34 to 147 breeding individuals, while 63% of them had declining population trends in 1994, compared to 81% that were increasing by 2004 (Fig. 59).

A second study (Brooke et al. 2008) examined the rate at which species have moved through the IUCN Red List categories towards extinction during the same decade, and showed that conservation action has substantially slowed this trajectory. Among CR species, although three had gone extinct by 2004, 49 (28%) benefited from conservation action such that they declined less severely or improved in status. An additional 47 (27%) gained marginal benefits from conservation action. Hence, conservation action has for many species slowed, halted or even reversed the rates of decline driven by human-induced threats, and for a suite of 16 species saved them, at least temporarily, from extinction.

BirdLife’s Preventing Extinctions Programme builds on these successes. It is spearheading greater conservation action, awareness and funding for the world’s most threatened birds, through appointing “Species Guardians” (to implement the priority actions) and “Species Champions” (to provide the resources: see www.birdlife.org/extinction). To date, 55 Species Champions have been recruited, committing over US$3 million to implement action by 34 Species Guardians for 56 CR and EN bird species. Examples include Pingo D’Água, a local organisation implementing research, environmental education and advocacy for Restinga Antwren (Formicivora littoralis) CR at Cabo Frio, Brazil, and SOPI (Sociedad Ornitológica Puertorriqueña Inc.) carrying out surveys, community awareness and action planning for Puerto Rican Nightjar (Caprimulgus noctitherus) CR.

A growing challenge

There are many reasons to be optimistic despite the parlous state of nature in 2010, and notwithstanding the long catalogue of anthropogenic pressures on birds with which this essay begins. The success stories described above demonstrate that conservation can work: we have the knowledge and tools to turn around the fortunes of species at risk, provided adequate resources and political will are applied. There are also many heartening cases of threats being averted: a canal that would have wiped out much of the habitat of Jerdon’s Courser in India was re-routed in response to public outcry (BirdLife International 2008g); the Augustow Primeval Forest and the magnificent Rospuda Valley in Poland have been saved from the threat of the Via Baltica road development (BirdLife International 2010d); governments of India, Nepal and Pakistan have banned the manufacture of the veterinary drug diclofenac which is deadly for vultures; both Cyprus and Malta have prohibited hunting of spring migrants (BirdLife International 2009e, 2009f); and the USA decided not to allow the expansion of industrial fishing into the Arctic north of the Bering Strait (BirdLife International 2009g).

Furthermore, there are plenty of examples of bird species and their habitats receiving better protection: local communities on the Fijian island of Kadavu are working to tie forest conservation in IBAs to the development of sustainable agricultural practices (BirdLife International 2009h); Timor-Leste has declared its first national park, which will provide sanctuary for 100 Critically Endangered Yellow-crested Cockatoos, among other biodiversity (BirdLife International 2008h); Brazil and Uruguay have become the most recent countries to endorse the Agreement on the Conservation of Albatrosses and Petrels (ACAP 2010); and Mexico has passed a law banning the capture and export of wild parrots (American Bird Conservancy 2008b).

Finally there are encouraging signs of businesses and governments taking the issue of biodiversity conservation more seriously: TransCanada Corporation has committed almost US$1 million to support community caretakers for Canadian IBAs (BirdLife International 2009i); Rio Tinto Alcan is supporting conservation of Kakapo (Strigops habroptila) as a BirdLife Species Champion (BirdLife International 2008i); Bayer CropScience has withdrawn from the USA market disulfoton and methami­dophos, two organophosphates that are already banned in many other parts of the world (American Bird Conservancy 2009b); and Ecuador has changed its constitution to recognise the rights of nature (American Bird Conservancy 2008c).

Nevertheless, the scale of the challenge is continuing to grow, and for all the conservation achievements over the past half-century or so, the global community of people passionate about birds must now seriously scale up their response to meet this increased challenge. Most high-profile success stories for species to date have been on small islands, where the problems are in some respects more tractable. Improving the status of threatened species with broader ranges on larger land-masses is generally considerably more challenging and expensive. The cost of implementing all the actions described in the Hawaiian Crow five-year recovery plan, which includes broad-scale habitat restoration, has been estimated at over US$14 million (USFWS 2003b). If saving all CR birds came with the same price-tag, the bill would come to US$2·7 billion—a substantial figure, but still less than the sum spent by the USA every four days on the war in Iraq.

Furthermore, recent work has shown that population sizes of several thousands (not hundreds) of individuals are required for a species to have a reasonable probability of riding out environmental fluctuation and stochastic events in the long term (Traill et al. 2009). This raises the bar higher than many conservation projects have hitherto aimed, and emphasises further the size of the challenge we face. Moreover, this is all to be set against a background of ever-increasing consumption by expanding human populations. In this context, economies that do not account adequately for the value of biodiversity will continue to promote the destruction of natural habitats and the intensification of land-use, thus deepening the biodiversity crisis. Fundamental changes are needed in the way that we plan and regulate economic development (particularly the agricultural sector), and a much higher level of government resolve and leadership is essential. Experience to date shows that the free market alone is unlikely to deliver what is required, as evidenced, for example, by the limited uptake so far of certification schemes for sustainable forest management.

Inspiring, engaging and empowering people

Ultimately, biodiversity will only be conserved if enough people care about nature and recognise its importance for human livelihoods and wellbeing, as well as its intrinsic value. Changes in attitudes and approaches are needed at local, regional and global scales among individuals, communities, businesses and governments. This is of course as easy to say as it is difficult to achieve. The world is dominated so strongly by conflicting economic, national, religious, tribal and criminal interests, and is defined so powerfully by priorities relating to war, profit, personal advancement, poverty and disease, that the notion of “changes in attitudes” is almost risible. However, as biodiversity loss, climate change, human migration, overpopulation, water shortages, declining soil fertility and other products of human mismanagement of the planet increasingly discomfort voters and governments, such changes towards a more holistic pattern of production and consumption may indeed begin to occur.

At the local scale, action on the ground can be achieved through empowering local people. Across the world, a diverse network of “IBA Local Conservation Groups” has developed in recent years, each sharing a commitment to conserve the biodiversity of a particular site, and carrying out activities including monitoring, local advocacy, education and awareness, and development of livelihoods linked to biodiversity conservation. For example, in the Middle East, the traditional hima system is being revived by such groups, under which local communities manage natural areas and protect them from over-exploitation, through combining a mixture of strict protection and sustainable use. In Lurg, Australia, almost 18,000 volunteers have been involved in tree-planting and habitat restoration for the Regent Honeyeater (Xanthomyza phrygia) EN over the last 15 years (Dooley 2009).

At the other end of the scale, the corporate sector has an enormous impact on the global environment, particularly those businesses directly involved in agriculture, forestry or extraction of minerals or fossil fuels. Conservation organisations are increasingly developing strategic partnerships with industry to help businesses minimise their environmental damage, enabling them to secure a “licence to operate” and engage with the concept of sustainable development while also providing collaborative support for much-needed conservation action on the ground.

Across the world, the number of people interested in, inspired by and taking action for birds and their conservation is growing. The BirdLife partnership of more than 100 national non-governmental organisations has expanded from an estimated 1·7 million members in 1994 to well over 2·3 million members worldwide today, providing a powerful voice for the environment in many countries. Many additional individuals belong to local conservation organisations. The largest BirdLife partners are found in wealthier countries where there is a tradition of birdwatching. However, partners are growing fast in many developing countries. For example, Nature Uganda has few members compared to the country’s population (c. 22 million people) but the membership is increasing rapidly (Fig. 60). Nature Uganda also engages with many additional people in rural areas around IBAs, and many school and college students.

The rise of the internet has made it much easier for large numbers of people to get involved in conservation, in particular through “citizen science” projects mobilising large numbers of volunteer recorders to monitor species and sites (Greenwood 2007). Projects range from reporting relatively simple lists of bird sightings to long-term sophisticated monitoring. About 400,000 people each year participate in the UK’s Big Garden Birdwatch by counting garden birds for one hour on a set weekend in January, providing an annual picture of how different species are faring (RSPB 2008), while 60,000 observers contribute to National Audubon’s North American Christmas Bird Count (LeBaron 2009), and almost 10,000 people are involved in Birds in Backyards surveys in Australia (J. Sutfin in litt. 2010). More generally, the Worldbirds website (www.worldbirds.org) brings together bird data collection and reporting systems from most countries across the world. It enables people to participate in their own language and add lists of the species they have seen at particular sites, and to find out where to see species and the latest sightings at different locations. More sophisticated monitoring systems with specific census methodologies also commonly engage large numbers of volunteers: over 3000 people contribute to the North American Breeding Bird Survey each year (G. Butcher in litt. 2009), 5000 observers collected over 7·3 million records for The Atlas of Southern African Birds (Harrison et al. 1997), over 7000 people have contributed over 7·1 million bird records to the Atlas of Australian Birds (J. Sutfin in litt. 2010), over 10,000 people are involved in national bird population monitoring schemes in Europe, and 15,000 observers in 110 countries count 30–40 million waterbirds at 10,000 sites every year as part of the international waterbird census (S. Delany in litt. 2009).

The view from 2010

Thanks to the contributions of thousands of people and hundreds of organisations—and indeed to the synthesising endeavours of the many authors of HBW itself—we know much more about the state of the world’s birds than we did when HBW began almost two decades ago. We also understand better the pressures upon the world’s birds, and the actions needed to tackle them. The public and decision-makers have become far more aware of the enormous environmental challenges that society faces, particularly in the light of climate change. There is also a greater understanding of the need to maintain biodiversity to deliver the ecosystem services on which human populations, particularly the world’s poor, depend. Despite this, the state of the world’s biodiversity is getting worse. Data from birds—the best known class of organisms—show that we have failed to meet the 2010 target of significantly reducing the rate of biodiversity loss, set by the world’s leaders a decade ago (Butchart et al. 2010). We now need governments to back up their commitments to conserve biodiversity and safeguard the environment with adequate resources and genuine political action. Readers of HBW can play their part, by minimising their own consumption and impacts, demanding environmentally sustainable policies from their governments, promoting the importance and urgency of responses to the biodiversity crisis, raising awareness, and supporting BirdLife partners and other conservation and environmental organisations at home and abroad.

Our lives are enriched by the extraordinary spectacles that birds provide, with their stunning plumages, dazzling courtship displays, beautiful songs, intriguing behaviours, graceful flight and remarkable migrations. If we want to allow future generations the chance to experience these delights and to benefit from the ecosystem services that biodiversity provides, then we need to get serious about making positive and significant changes in the way we live our lives and value the environment in our decisions.


Stuart H. M. Butchart, Nigel J. Collar, Alison J. Stattersfield and Leon A. Bennun


with contributions from:


Tristram Allinson, Muhtari Aminu-Kano, Jeremy P. Bird, Ian J. Burfield,
John H. Fanshawe, Lincoln D. C. Fishpool, Melanie Heath, Vicky R. Jones,
Cleo Small, Andy Symes and David Thomas


We are grateful to: John Sherwell and Christine Alder for help in tracking down various references; Ian May, Mike Evans and Mark Balman for help with extracting data; Mark Anderson, Pep Arcos, Jonathan Barnard, Boris Barov, Luigi Boccaccio, Tom Brooks, Tim Brown, Ariel Bruner, Ian Burfield, Greg Butcher, Rob Calvert, Simba Chan, Mike Crosby, John Croxall, Nick Davidson, Simon Delany, Guy Dutson, Virginia Escandell, Stephen Garnett, Richard Gregory, Richard Grimmett, Martin Jenkins, Johannes Kamp, Konstantin Kreiser, Joe Leitmann, Gerald McCormack, Rob Munroe, Richard Phillips, John Pilgrim, Danny Rogers, Roger Safford, John Sauer, Rob Sheldon, Ben Sullivan, Jennifer Sutfin, Frances Taylor, Phil Taylor, David Thomas, Matthew Webb and Tony Whitten for kindly providing information, comments or help in other ways. We thank the thousands of species experts, birdwatchers, scientists and conservationists who contributed information to BirdLife’s Red List assessments for the world’s birds; they are acknowledged and listed in the species factsheets available at http://www.birdlife.org/datazone/species/index.html and in BirdLife International (2008a). We also thank the data contributors to BirdLife’s Global Procellariiform Tracking Database, upon which Fig. 57 is based: Akira Suzuki, Amanda Freeman, British Antarc­tic Survey, Christopher Robertson, Dave Anderson, David Hyrenbach, David Nicholls, Deon Nel, Donna Patterson, Flavio Quintana, Graham Robertson, Henri Weimerskirch, Jacob González-Solís, Japanese Ministry of Environment, Javier Arata, Jean-Claude Stahl, Jill Awkerman, Kath Walker, Mark Schultz, Michelle Hester, Michelle Kappes, Nic Huin, Nic Klomp, Paul Sagar, Peter Ryan, Rachael Alderman, Richard Cuthbert, Rob Suryan, Rosemary Gales, Ross Wanless, Samantha Petersen, Scott Shaffer, Susan Waugh and Vitor Paiva.


  • ACAP [=Agreement on the Conservation of Albatrosses and Petrels] (2010). Parties to ACAP. Available at: http://www.acap.aq/resources/parties-to-acap.
  • ACIA [=Arctic Climate Impact Assessment] (2004). Impacts of Warming; Arctic Climate Impact Assessment. Cambridge University Press, Cambridge, UK.
  • Ainley, D., Russell, J. & Jenouvrier, S. (2008). The fate of Antarctic penguins when Earth’s tropospheric temperature reaches 2°C above pre-industrial levels. Available at: http://www.panda.org/antarctica.
  • Amar, A., Amidon, F., Arroyo, B., Esselstyn, J.A. & Marshall, A.P. (2008). Population trends of the forest bird community on the Pacific island of Rota, Mariana Islands. Condor 110: 421–427.
  • American Bird Conservancy (2008a). Pilot hi-tech study searches for rare Hawaiian birds. Available at: http://www.abcbirds.org/newsandreports/stories/081203.html.
  • American Bird Conservancy (2008b). Mexican parrot trade ban a boost to conservation efforts. Available at: http://www.abcbirds.org/newsandreports/stories/081126.html.
  • American Bird Conservancy (2008c). Ecuador passes unique constitutional amendment protecting nature. Available at: http://www.abcbirds.org/newsandreports/stories/081001.html.
  • American Bird Conservancy (2009a). Energy developments threaten Sage-grouse habitat in Wyoming. Available at: http://www.abcbirds.org/newsandreports/stories/090106.html.
  • American Bird Conservancy (2009b). Government announces two toxic pesticides removed from U.S. market. Available at: http://www.abcbirds.org/newsandreports/stories/091009.html.
  • American Bird Conservancy (2010a). US taking action to enforce the Migratory Bird Treaty Act. Available at: http://www.abcbirds.org/newsandreports/stories/100113.html.
  • American Bird Conservancy (2010b). Contaminants continue to pose threat to Osprey in Chesapeake Bay. Available at: http://www.abcbirds.org/newsandreports/stories/100128.html.
  • American Bird Conservancy (2010c). Bird conservation group releases list of critical sites most at risk from Gulf oil spill. Available at: http://www.abcbirds.org/newsandreports/releases/100430.html.
  • Anand, M.O., Krishnaswamy, J. & Das, A. (2008). Proximity to forest drives bird conservation value of coffee plantations: implications for certification. Ecol. Appl. 18: 1754–1763.
  • Anderson, M.D. (2008). A vision in pink. Africa Birds & Birding 13(2): 42–49.
  • Anggraini, K., Kinnaird, M. & O’Brien, T. (2000). The effects of fruit availability and habitat disturbance on an assemblage of Sumatran hornbills. Bird Conserv. Int. 10: 189–202.
  • Anielski, M. & Wilson, S. (2009). Counting Canada’s Natural Capital: Assessing the Real Value of Canada’s Boreal Ecosystems. Canadian Boreal Initiative & The Pembina Institute, Ottawa, Ontario & Drayton Valley, Alberta, Canada.
  • Anon. (2002). Northern Bald Ibis breeding in Syria. World Birdwatch 24(3): 2.
  • Anon. (2007). Sociable Lapwing lives up to its name. World Birdwatch 29(4): 9.
  • Aratrakorn, S., Thunhikorn, S. & Donald, P.F. (2006). Changes in bird communities following conversion of lowland forest to oil palm and rubber plantations in southern Thailand. Bird Conserv. Int. 16: 71–82.
  • Araújo, M.B. (2003). The coincidence of people and biodiversity in Europe. Global Ecol. Biogeogr. 12: 5–12.
  • Auman, H.J., Ludwig, J.P., Giesy, J.P. & Colborn, T. (1997). Plastic ingestion by Laysan Albatross chicks on Sand Island, Midway Atoll, in 1994 and 1995. Pp. 239–244 in: Robertson, G. & Gales, R. eds. (1997). Albatross Biology and Conservation. Surrey Beatty & Sons, Chipping Norton, New South Wales, Australia.
  • Bagyura, B., Szitta, T., Sándor, I., Viszló, L., Firmánszky, G., Forgách, B., Boldogh, S. & Demeter, I. (2004). A review of measures taken against bird electrocution in Hungary. Pp. 423–428 in: Chancellor, R. D. & Meyburg, B.U. eds. (2004). Raptors Worldwide. World Working Group on Birds of Prey and Owls & MME/BirdLife Hungary, Berlin & Budapest.
  • Baker, A.J., González, P.M., Piersma, T., Niles, L.J., de Lima Serraro do Nascimento, I., Atkinson, P.W., Clark, N.A., Minton, C.D.T., Peck, M.K. & Aarts, G. (2004). Rapid population decline in Red Knots: fitness consequences of decreased refuelling rates and late arrival in Delaware Bay. Proc. Royal Soc. London (Ser. B Biol. Sci.) 271: 875–882.
  • Balmford, A., Moore, J.L., Brooks, T., Burgess, N., Hansen, L.A., Williams, P. & Rahbek, C. (2001). Conservation conflicts across Africa. Science (Washington, D.C.) 291: 2616–2619.
  • Balmford, A., Bruner, A., Cooper, P., Costanza, R., Farber, S., Green, R.E., Jenkins, M., Jefferiss, P., Jessamy, V., Madden, J., Munro, K., Myers, N., Naeem, S., Paavola, J., Rayment, M., Rosendo, S., Roughgarden, J., Trumper, K. & Turner, R.K. (2002). Economic reasons for conserving wild nature. Science (Washington, D.C.) 297: 950–953.
  • Beaumont, L.J., McAllan, A.W. & Hughes, L. (2006). A matter of timing: changes in the first date of arrival and last date of departure of Australian migratory birds. Global Change Biol. 12: 1339–1354.
  • Beintema, N.H. (2001). Lead Poisoning in Waterbirds: International Update Report 2000. Wetlands International, Wageningen, The Netherlands.
  • Bennett, P.M. & Owens, I.P.F. (1997). Variation in extinction-risk among birds: chance or evolutionary predisposition? Proc. Royal Soc. London (Ser. B Biol. Sci.) 264: 401–408.
  • Bennett, S., Kazemi, S., Kelly, S., Mardack, P., Nelson, N. & Hosking, J. (2007). The possible effects of projected sea-level rise. Page 17 in: Olsen, P. ed. (2007). The State of Australia’s Birds 2007: Birds in a Changing Climate. Wingspan 14(4) (Supplement). Birds Australia, Victoria.
  • Benning, T.L., LaPointe, D., Atkinson, C.T. & Vitousek, P.M. (2002). Interactions of climate change with biological invasions and land use in the Hawaiian Islands: modeling the fate of endemic birds using a geographic information system. Proc. Natl. Acad. Sci. USA 99: 14246–14249.
  • Beolens, B. (2010). Birding: United Kingdom: general. Available at: www.fatbirder.com/links_geo/europe/uk.html.
  • Bhattacharya, S. (2003). Wild coal fires are a ‘global catastrophe’. Available at: http://
  • www.newscientist.com/article/dn3390-wild-coal-fires-are-a-global-catastrophe.html.
  • Bibby, C.J., Collar, N.J., Crosby, M.J., Heath, M.F., Imboden, C., Johnson, T.H., Long, A.J., Stattersfield, A.J. & Thirgood, S.J. (1992). Putting Biodiversity on the Map. International Council for Bird Preservation, Cambridge, UK.
  • BirdLife Asia (2009). Safeguarding Important Bird Areas of Natural Heritage alongside Economic Development. Mongolia Discussion Papers. World Bank East Asia & Pacific Region Sustainable Development Department, Washington D.C.
  • BirdLife International (2000). Threatened Birds of the World. Lynx Edicions & BirdLife International, Barcelona & Cambridge, UK.
  • BirdLife International (2001). Threatened Birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, UK.
  • BirdLife International (2004a). Threatened Birds of the World 2004. CD-ROM. BirdLife International, Cambridge, UK.
  • BirdLife International (2004b). State of the World’s Birds 2004. BirdLife International, Cambridge, UK.
  • BirdLife International (2004c). Tracking Ocean Wanderers: the Global Distribution of Albatrosses and Petrels. Results from the Global Procellariform Tracking Workshop, 1–5 September 2003, Gordon’s Bay, South Africa. BirdLife International, Cambridge, UK.
  • BirdLife International (2004d). Danube canal bad news for wildlife. Available at: http://www.birdlife.org/news/news/2004/05/danube_canal.html.
  • BirdLife International (2005). Bulgarian windfarms threaten migratory birds. Available at: http://www.birdlife.org/news/news/2005/08/bulgaria_windfarm.html.
  • BirdLife International (2006a). The Little Bustard in France: threatened with extinction by biofuels and ineffective policy tools. Farming for Life Newsl. 2: 2.
  • BirdLife International (2006b). Wind farm causes eagle deaths. Available at: http://www.birdlife.org/news/news/2006/02/norway.html.
  • BirdLife International (2007a). Grenada Government defiant as dove sanctuary protest grows. Available at: http://www.birdlife.org/news/news/2007/02/grenada_dove_update.html.
  • BirdLife International (2007b). Largest flock for 100 years: Lapwing lives up to its name. News story available at: http://www.birdlife.org/news/news/2007/10/lapwing_superflock.html.
  • BirdLife International (2008a). Threatened Birds of the World 2008. CD-ROM. BirdLife International, Cambridge, UK.
  • BirdLife International (2008b). State of the world’s birds. BirdLife International, Cambridge, UK. Available at: http://www.biodiversityinfo.org/default.php?r=sowbhome.
  • BirdLife International (2008c). Agreement secures safer power lines for Hungary’s birds. Available at: http://www.birdlife.org/news/news/2008/03/Hungary_powerlines.html.
  • BirdLife International (2008d). Local increase in vultures thanks to diclofenac campaign in Nepal. Available at: http://www.birdlife.org/news/news/2008/01/nepal_vultures.html.
  • BirdLife International (2008e). Short-tailed Albatross chicks moved out of the shadow of the volcano. Available at: http://www.birdlife.org/news/news/2008/03/start_translocation.html.
  • BirdLife International (2008f). Returned Lorikeets breed on Atiu. Available at: http://www.birdlife.org/news/news/2008/10/kura_breeding.html.
  • BirdLife International (2008g). Canal diverted to save Jerdon’s Courser. Available at: http://www.birdlife.org/news/news/2008/08/jerdons_courser.html.
  • BirdLife International (2008h). Timor-Leste’s first national park will protect the community’s “wealth”. Available at: http://www.birdlife.org/news/news/2008/09/timor_reserve.html.
  • BirdLife International (2008i). Business answers conservation call. Available at: http://www.birdlife.org/news/news/2008/09/pep_new_champ.html.
  • BirdLife International (2009a). Hunting: an extinction threat to Middle East’s most threatened bird. Available at: http://www.birdlife.org/news/news/2009/09/nbi_shooting.html.
  • BirdLife International (2009b). Romanian Parliament puts Danube Delta at risk. Available at: http://www.birdlife.org/news/news/2009/11/danube_delta.html.
  • BirdLife International (2009c). Wildlife poisoning in Africa. Available at: http://www.birdlife.org/news/news/2009/11/africa_furadan.html.
  • BirdLife International (2009d). Natron community vows to protect the lake and its flamingos. Available at: http://www.birdlife.org/news/news/2009/10/natron_community.html.
  • BirdLife International (2009e). Will Cyprus spring shooting be banned forever? Available at: http://www.birdlife.org/news/news/2009/05/cyprus_shooting.html.
  • BirdLife International (2009f). Malta bans spring hunting. http://www.birdlife.org/news/news/2009/03/malta_spring_hunting.html.
  • BirdLife International (2009g). US fisheries act to protect Arctic and albatrosses. Available at: http://www.birdlife.org/news/news/2009/03/alaskan_fisheries_protected.html.
  • BirdLife International (2009h). New grassroots approach helps conserve Fijian forest. Available at: http://www.birdlife.org/news/news/2009/06/kadavu_conservation.html.
  • BirdLife International (2009i). TransCanada Corporation commits a million dollars to bird conservation. Available at: http://www.birdlife.org/news/news/2009/06/transcanada.html.
  • BirdLife International (2010a). The 2010 IUCN Red List of threatened birds. Species factsheets available at: http://www.birdlife.org/datazone/species/index.html.
  • BirdLife International (2010b). Uranium mining and Important Bird Areas in Namibia: a need for strategic environmental assessment. Available at: http://www.biodiversityinfo.org/casestudy.php? id=129.
  • BirdLife International (2010c). Building capacity for sustainable hunting of migratory birds in the Mediterranean countries of North Africa and the Middle East. Available at: http://www.birdlife.org/action/change/sustainable_hunting/index.html.
  • BirdLife International (2010d). Better late than never. Available at: http://www.birdlife.org/news/extra/europe/rospuda_january.html.
  • Bisseleua, D.H.B., Missoup A.D. & Vidal, S. (2009). Biodiversity conservation, ecosystem functioning and economic incentives under cocoa agroforestry intensification. Conserv. Biol. 23: 1176–1184.
  • Blaser, J. & Robledo, C. (2007). Initial analysis on the mitigation potential in the forestry sector. Unpublished report prepared for the UNFCCC Secretariat. Intercooperation, Bern.
  • Both, C., Bouwhuis, S., Lessells, C.M. & Visser, M.E. (2006). Climate change and population declines in a long-distance migratory bird. Nature (London) 441: 81–83.
  • Both, C., van Turnhout, C.A.M., Bijlsma, R.G., Siepel, H., van Strien, A.J. & Foppen, R.P.B. (2010). Avian population consequences of climate change are most severe for long-distance migrants in seasonal habitats. Proc. Royal Soc. London (Ser. B Biol. Sci.). 277: 1259–1266.
  • Bowden, C. (2009). The Asian Gyps vulture crisis: the role of captive breeding in India to prevent total extinction. Birding Asia 12: 121–123.
  • Brandes, T.S. (2008). Automated sounds recording and analysis techniques for bird surveys and conservation. Bird Conserv. Int. 18: S163–S173.
  • Brereton, T., Wigglesworth, T., Warren, M.S. & Stewart, K. (2005). Agri-environment schemes and butterflies: re-assessing the impacts and improving delivery of BAP targets. Butterfly Conservation Final Project Report to DEFRA. Butterly Conservation, Wareham, UK.
  • Bristol, R., Millett, J. & Shah, N.J. (2005). Best Practice Handbook for Management of a Critically Endangered Species: the Seychelles Magpie Robin. Nature Seychelles, Mahé, Seychelles.
  • Brommer, J. (2004). The range margins of northern birds shift polewards. Ann. Zool. Fennici 41: 391–397.
  • Brooke, M.L., Butchart, S.H.M., Garnett, S.T., Crowley, G.M., Mantila-Beniers, N.B & Stattersfield, A.J. (2008). Rates of movement of threatened bird species between IUCN Red List categories and toward extinction. Conserv. Biol. 22: 417–427.
  • Brooks, T.M., Pimm, S.L. & Oyugi, J.O. (1999). How long is the time lag between deforestation and bird extinction in tropical forest fragments? Conserv. Biol. 13: 1140–1150.
  • Brooks, T., Balmford, A., Burgess, N., Hansen, L.A., Moore, J., Rahbek, C., Williams, P., Bennun, L., Byaruhanga, A., Kasoma, P., Njoroge, P., Pomeroy, D. & Wondafrash, M. (2001). Conservation priorities for birds and biodiversity: do East African Important Bird Areas represent species diversity in other terrestrial vertebrate groups? Ostrich (Suppl.) 15: 3–12.
  • Brothers, N. (1991). Albatross mortality and associated bait loss in the Japanese longline fishery in the southern-ocean. Biol. Conserv. 55: 255–268.
  • Bryant, D., Nielsen, D. & Tangley, L. (1997). The Last Frontier Forests: Ecosystems and Economies on the Edge. World Resources Institute, Washington, D.C.
  • BTO [=British Trust for Ornithology] (2009). Bird ringing. Available at: http://www.bto.org/research/researchsummary/5birdringing.htm#admin.
  • Buchanan, G.M., Butchart, S.H.M., Dutson, G.C.L., Pilgrim, J.D., Steininger, M.K., Bishop, K.D. & Mayaux, P. (2008). Using remote sensing to inform conservation status assessment: estimates of recent deforestation rates on New Britain and the impacts upon endemic birds. Biol. Conserv. 141: 56–66.
  • Burgess, N.D., Rahbek, C., Larsen, F.W., Williams, P. & Balmford, A. (2002). How much of the vertebrate diversity of sub-Saharan Africa is catered for by recent conservation proposals? Biol. Conserv. 107: 327–339.
  • Butchart, S.H.M. (2008). Red List Indices to measure the sustainability of species use and impacts of invasive alien species. Bird Conserv. Int. 18 (Suppl.): 245–262.
  • Butchart, S.H.M. & Bird, J. (2009). Data Deficient birds on the IUCN Red List: what don’t we know? Biol. Conserv. 143: 239-247.
  • Butchart, S.H.M., Stattersfield, A.J., Bennun, L.A., Shutes, S.M., Akçakaya, H.R., Baillie, J.E.M., Stuart, S.N., Hilton-Taylor, C. & Mace, G.M. (2004). Measuring global trends in the status of biodiversity: Red List Indices for birds. Public Libr. Sci. Biol. 2: 2294–2304.
  • Butchart, S.H.M., Stattersfield, A.J., Bennun, L.A., Akçakaya, H.R., Baillie, J.E.M., Stuart, S.N., Hilton-Taylor, C. & Mace, G.M. (2005). Using Red List Indices to measure progress towards the 2010 target and beyond. Phil. Trans. Roy. Soc. London (Ser. B) 1454: 255–268.
  • Butchart, S.H.M., Stattersfield, A.J. & Brooks, T.M. (2006a). Going or gone: defining ‘Possibly Extinct’ species to give a truer picture of recent extinctions. Bull. Brit. Orn. Club 126A: 7–24.
  • Butchart, S.H.M., Stattersfield, A.J. & Collar, N.J. (2006b). How many bird extinctions have we prevented? Oryx 40: 266–278.
  • Butchart, S.H.M., Akçakaya, H.R., Chanson, J., Baillie, J.E.M., Collen, B., Quader, S., Turner, W.R., Amin, R., Stuart, S.N., Hilton-Taylor, C. & Mace, G.M. (2007). Improvements to the Red List Index. Public Libr. Sci. ONE 2: e140.
  • Butchart, S.H.M., Walpole, M., Collen, B., van Strien, A., Scharlemann, J.P.W., Almond, R.E.E., Baillie, J.E.M., Bomhard, B., Brown, C., Bruno, J., Carpenter, K.E., Carr, G.M., Chanson, J., Chenery, A.M., Csirke, J., Davidson, N.C., Dentener, F., Foster, M., Galli, A., Galloway, J.N., Genovesi, P., Gregory, R.D., Hockings, M., Kapos, V., Lamarque, J.-F., Leverington, F., Loh, J., McGeoch, M.A., McRae, L., Minasyan, A., Morcillo, M.H., Oldfield, T.E.E., Pauly, D., Quader, S., Revenga, C., Sauer, J.R., Skolnik, B., Spear, D., Stanwell-Smith, D., Stuart, S.N., Symes, A., Tierney, M., Tyrrell, T.D., Vié, J.C. & Watson, R. (2010). Global biodiversity: indicators of recent declines. Science (Washington, D.C.) 328: 1164–1168.
  • Butcher, G.S. & Niven, D.K. (2007). Combining Data from the Christmas Bird Count and the Breeding Bird Survey to Determine the Continental Status and Trends of North American Birds. National Audubon Society, New York.
  • Butler, C.J. (2003). The disproportionate effect of global warming on the arrival dates of short-distance migratory birds in North America. Ibis 145: 484–495.
  • Butler, R.A. (2007a). U.S. corn subsidies drive Amazon destruction. Mongabay Press release. Available at: http://news.mongabay.com/2007/1213-amazon_corn_sub.html.
  • Butler, R.A. (2007b). Biofuels driving destruction of Brazilian cerrado. Mongabay Press release. Available at: http://news.mongabay.com/2007/0821-cerrado.html.
  • Cade, T.J., Osborn, S.A.H., Hunt, W.G. & Woods, C.P. (2004). Commentary on released California Condors Gymnogyps californianus in Arizona. Pp. 11–25 in: Chancellor, R.D. & Meyburg, B.U. eds. (2004). Raptors Worldwide. World Working Group on Birds of Prey and Owls & MME/BirdLife Hungary, Berlin & Budapest.
  • Cadée, G.C. (2002). Seabirds and floating plastic debris. Mar. Pollut. Bull. 44: 1294–1295.
  • Caffrey, C., Smith, S.C.R. & Weston, T.J. (2005). West Nile Virus devastates an American Crow population. Condor 107: 128–132.
  • Carrete, M., Sánchez-Zapata, J.A., Benítez, J.R., Lobón, M. & Donázar, J.A. (2009). Large scale risk-assessment of wind-farms on population viability of a globally endangered long-lived raptor. Biol. Conserv. 142: 2954–2961.
  • Chambers, L.E. (2007). Is climate change affecting Australia’s birds? Pp. 7–8 in: Olsen, P. ed. (2007). The State of Australia’s Birds 2007: Birds in a Changing Climate. Wingspan 14(4) (Supplement). Birds Australia, Victoria.
  • Chambers, J.Q., Higuchi, N. & Schimel, J.P. (1998). Ancient trees in Amazonia. Nature (London) 391: 135–136.
  • Chan, S., Chen, S.H. & Yuan, H.W. (2010). International Single Species Action Plan for the conservation of the Chinese Crested Tern (Sterna bernsteini). BirdLife International Asia Division & CMS Secretariat, Tokyo &Bonn.
  • Chen, H., Smith, G.J.D., Zhang, S.Y., Qin, K., Wang, J., Li, K.S., Webster, R.G., Peiris, J.S.M. & Guan, Y. (2005). Avian flu: H5N1 virus outbreak in migratory waterfowl. Nature (London) 436: 191–192.
  • Chen, S.H., Chang, S.H., Liu, Y., Chan, S., Fan, Z.Y., Chen, C.S., Yen, C.W., & Guo, D.S. (2009). Low population and severe threats: status of the Critically Endangered Chinese Crested Tern Sterna bernsteini. Oryx 43: 209–212.
  • Choi, H. (2008). Are we growing smart?: a new vision for urban development in Asia and the Pacific. Asia-Pacific Develop. J. 2: 1–12.
  • Clay, J. (2004). Palm Oil. World Agriculture and the Environment: a Commodity by Commodity Guide to Impacts and Practices. Island Press, Washington, D.C.
  • Collar, N.J. (1998). Extinction by assumption; or, the Romeo Error on Cebu. Oryx 32: 239–244.
  • Collar, N.J. (1999). Risk indicators and status assessment in birds. Pp.13–28 in: del Hoyo, J., Elliott, A. & Sargatal, J. eds. (1999). Handbook of the Birds of the World. Vol. 5. Barn-owls to hummingbirds. Lynx Edicions, Barcelona.
  • Collar, N.J. & Andrew, P. (1988). Birds to Watch: the ICBP World Checklist of Threatened Birds. International Council for Bird Preservation & International Union for Conservation of Nature and Natural Resources, Cambridge, UK.
  • Cook, A. (2008). Loss of set-aside threatens farmland bird recovery. RSPB press release. Available at: http://www.rspb.org.uk/media/releases/details.asp?id=tcm:9-182116.
  • Copello, S. & Quintana, F. (2003). Marine debris ingestion by Southern Giant Petrels and its potential relationships with fisheries in the Southern Atlantic Ocean. Mar. Pollut. Bull. 46: 1504–1515.
  • Costanza, R., d’Arge, R., de Groot, R., Farberk, S., Grasso, M., Hannon, B., Limburg, K., Naeem S., O’Neill, R.V., Paruelo, J., Raskin, R.G., Sutton, P. & van den Belt, M. (1997). The value of the world’s ecosystem services and natural capital. Nature (London) 387: 253–260.
  • Crick, H.Q., Dudley, C., Glue, D.E. & Thomson, D.L. (1997). UK birds are laying eggs earlier. Nature (London) 388: 526.
  • Crosbie, S.P., Koenig, W.D., Reisen, W.K., Kramer, V.L., Marcus, L., Carney, R., Pandolfino, E., Bolen, G.M., Crosbie, L.R., Bell, D.A. & Ernest, H.B. (2008). Early impact of West Nile Virus on the Yellow-billed Magpie Pica nuttalli. Auk 125: 542–550.
  • Croxall, J.P. (2008). The role of science and advocacy in the conservation of Southern Ocean albatrosses at sea. Bird Conserv. Int. 18: S13–S29.
  • Croxall, J.P. & Nicol, S. (2004). Management of Southern Ocean resources: global forces and future sustainability. Antarct. Sci. 16: 569–584.
  • Croxall, J.P., Prince, P.A., Rothery, P. & Wood, A.G. (1998). Population changes in albatrosses at South Georgia. Pp. 68–83 in: Robertson, G. & Gales, R. eds. (1998). Albatross Biology and Conservation. Surrey Beatty & Sons, Chipping Norton, New South Wales, Australia.
  • Cunningham, R. & Olsen, P. (2009). A statistical methodology for tracking long-term change in reporting rates of birds from volunteer-collected presence-absence data. Biodiversity Conserv. 18: 1305–1327.
  • Cuthbert, R., Green, R.E., Ranade, S., Saravanan, S., Pain, D.J., Prakash, V. & Cunningham, A.A. (2006). Rapid population declines of Egyptian Vulture (Neophron percnopterus) and Red-headed Vulture (Sarcogyps calvus) in India. Anim. Conserv. 9: 349–354.
  • D’Alba, L., Monaghan, P. & Nager, R.G. (2010). Advances in laying date and increasing population size suggest positive responses to climate change in Common Eiders Somateria mollissima in Iceland. Ibis 152: 19–28.
  • Danielson, E. & Heegaard, H. (1995). Impact of logging and plantation development on species diversity: a case study from Sumatra. Pp. 73–92 in: Sandbukt, Ø. ed. (1995). Management of Tropical Forests: Towards an Integrated Perspective. Centre for Development and the Environment, University of Oslo, Oslo.
  • Daunt, F., Wanless, S., Greenstreet, S.P.R., Jensen, H., Hamer, K.C. & Harris, M.P. (2008). The impact of the sandeel fishery closure on seabird consumption, distribution, and productivity in the northwestern North Sea. Can. J. Fish. Aquat. Sci. 65: 362–381.
  • Davidson, N.C. & Stroud, D.A. (2010). Long-term and accelerating declines in global shorebird population status: evidence of the 2010 global biodiversity target not being met? MS.
  • DEFRA [=Department for Environment, Food and Rural Affairs] (2009). Change in the area and distribution of uncropped land in England: January 2009 update. Available at: http://www.defra.gov.uk/evidence/statistics/foodfarm/enviro/observatory/research/documents/observatory13.pdf.
  • Delany, S. & Scott, D. (2006). Waterbird Population Estimates. Fourth Edition. Wetlands International, Wageningen, The Netherlands.
  • Demeter, I., Bagyura, J., Lovászi, P., Nagy, K., Kovács, A. & Horváth, M. (2004). [Medium-voltage Power Lines and Bird Mortality: Experience, Nature Conservation Requirements and Recommendations]. MME/BirdLife Hungary, Budapest. In Hungarian.
  • Derraik, J.G.B. (2002). The pollution of the marine environment by plastic debris: a review. Mar. Pollut. Bull. 44: 842–852.
  • Devictor, V., Julliard, R., Couvet, D. & Jiguet, F. (2008). Birds are tracking climate warming, but not fast enough. Proc. Royal Soc. London (Ser. B Biol. Sci.) 275: 2743–2748.
  • Devney, C.E. & Congdon, B. (2007). Demographic and reproductive impacts on seabirds? Pp. 14–15 in: Olsen, P. ed. (2007). The State of Australia’s Birds 2007: Birds in a Changing Climate. Wingspan 14(4) (Supplement). Birds Australia, Victoria.
  • DFID [=Department for International Development] (2007). Crime and Persuasion: Tracking Illegal Logging, Improving Forest Governance. Department for International Development, London.
  • Dinata, Y., Nugroho, A., Achmad Haidir, I. & Linkie, M. (2008). Camera trapping rare and threatened avifauna in west-central Sumatra. Bird Conserv. Int. 18: 30–37.
  • Dodson, J. & FitzGerald, G.J. (1980). Observations on the breeding biology of the boobies (Sulidae) at Clipperton Island, Eastern Pacific. Naturaliste Can. 107: 259–267.
  • Donald, P.F. (2004). Biodiversity impacts of some agricultural commodity production systems. Conserv. Biol. 18: 17–38.
  • Donald, P.F. & Morris, T.J. (2005). Saving the Sky Lark: new solutions for a declining farmland bird. Brit. Birds 98: 570–578.
  • Donald, P.F. & Vickery, J.A. (2000). The importance of cereal fields to breeding and wintering Skylarks Alauda arvensis in the UK. Pp. 140–150 in: Aebischer, N.J., Evans, A.D., Grice, P.V. & Vickery, J.A. eds. (2000). Proceedings of the 1999 BOU Spring Conference: Ecology and Conservation of Lowland Farmland Birds. British Ornithologists’ Union, Tring, UK.
  • Donald, P.F., Green, R.E. & Heath, M.F. (2001). Agricultural intensification and the collapse of Europe’s farmland bird populations. Proc. Royal Soc. London (Ser. B Biol. Sci.) 268: 25–29.
  • Donald, P.F., Pisano, G., Rayment, M.D. & Pain, D.J. (2002). The common agricultural policy, EU enlargement and the conservation of Europe’s farmland birds. Agric. Ecosyst. Environm. 89: 167–182.
  • Donald, P.F., Sanderson, F.J., Burfield, I.J. & van Bommel, F.P.J. (2006). Further evidence of continent-wide impacts of agricultural intensification on European farmland birds, 1990–2000. Agric. Ecosyst. Environm. 116: 189–196.
  • Donald, P.F., Sanderson, F.J., Burfield, I.J., Bierman, S.M., Gregory, R.D. & Waliczky, Z. (2007). International conservation policy delivers benefits for birds in Europe. Science (Washington, D.C.) 317: 810–813.
  • Dooley, S. (2009). Is the threatened species concept the next threatened species? Wingspan 19: 16–17.
  • Doswald, N., Willis, S.G., Collingham, Y.C., Pain, D.J., Green, R.E. & Huntley, B. (2009). Potential impacts of climatic change on the breeding and non-breeding ranges and migration distance of European Sylvia warblers. J. Biogeogr. 36: 1194–1208.
  • Ducks Unlimited (2007). Biofuels and ducks. Available at: http://www.ducks.org/DU_Magazine/DUMagazineMayJune2007/3213/BiofuelsandDucks.html.
  • Dutson, G.C.L., Magsalay, P.M. & Timmins, R.J. (1993). The rediscovery of the Cebu Flowerpecker Dicaeum quadricolor, with notes on other forest birds on Cebu, Philippines. Bird Conserv. Int. 3: 235–243.
  • EIA [=Environmental Investigation Agency] & Telepak (2008). Borderlines: Vietnam’s Booming Furniture Industry and Timber Smuggling in the Mekong Region. Environmental Investigation Agency & Telepak, London & Bogor, Indonesia.
  • Eken, G., Bennun, L., Brooks, T.M., Darwall, W., Fishpool, L.D.C., Foster, M., Knox, D., Langhammer, P., Matiku, P., Radford, E., Salaman, P., Sechrest, W., Smith, M.L., Spector, S. & Tordoff, A. (2004). Key biodiversity areas as site conservation targets. BioScience 54: 1110–1118.
  • Evans, W.R. & Manville, A.M. eds. (2000). Avian Mortality at Communication Towers. Cornell University Press, Ithaca, New York.
  • FAO [=Food and Agriculture Organization] (2005). A Global Strategy for the Progressive Control of Highly Pathogenic Avian Influenza (HPAI). Food and Agriculture Organization & World Organisation for Animal Health, Rome & Paris.
  • Fargione, J., Hill, J., Tilman, D., Polasky, S. & Hawthorne, P. (2008). Land clearing and the biofuel carbon debt. Science (Washington, D.C.) 319: 1235–1238.
  • Faria, D., Laps, R.R., Baumgarten, J. & Cetra, M. (2006). Bat and bird assemblages from forests and shade cacao plantations in two contrasting landscapes in the Atlantic forest of southern Bahia, Brazil. Biodiv. Conserv. 15: 587–612.
  • Feare, C.J. & Yasué, M. (2006). Asymptomatic infection with highly pathogenic avian influenza H5N1 in wild birds: how sound is the evidence? Virol. J. 3: 96.
  • Felton, A., Wood, J., Felton, A.M., Hennessey, B. & Lindenmayer, D.B. (2008). Bird community responses to reduced-impact logging in a certi?ed forestry concession in lowland Bolivia. Biol Conserv. 141: 545–555.
  • Ferro, M. (2000). Consumption of metal artefacts by Eurasian Griffons at Gamla Nature Reserve, Israel. Vulture News 43: 46–48.
  • Fimbel, R.A., Grajal, A. & Robinson, J.G. eds. (2001). The Cutting Edge: Conserving Wildlife in Logged Tropical Forests. Columbia University Press, New York.
  • Finkelstein, M.E., Doak, D.F., Nakagawa, M., Sievert, P.R. & Klavitter, J. (2010). Assessment of demographic risk factors and management priorities: impacts on juveniles substantially affect population viability of a long-lived seabird. Anim. Conserv. 13: 148–156.
  • Fisher, I.J., Pain, D.J. & Thomas, V.G. (2006). A review of lead poisoning from ammunition sources in terrestrial birds. Biol. Conserv. 131: 421–432.
  • Fitzpatrick, J.W., Lammertink, M., Luneau, M.D., Gallagher, T.W., Harrison, B.R., Sparling, G.M., Rosenberg, K.V., Rohrbaugh, R.W., Swarthout, E.C.H., Wrege, P.H., Swarthout, S.B., Dantzker, M.S., Charif, R.A., Barksdale, T.R., Remsen, J.V., Simon, S.D. & Zollner, D. (2005). Ivory-billed woodpecker (Campephilus principalis) persists in continental North America. Science (Washington, D.C.) 308: 1460–1462.
  • Fjeldså, J. & Rahbek, C. (1998). Continent-wide conservation priorities and diversification processes. Pp.139–160 in: Mace, G.M., Balmford A. & Ginsberg, J.R. eds. (1998). Conservation in a Changing World. Cambridge University Press, Cambridge, UK.
  • Frederiksen, M., Wanless, S., Harris, M.P., Rothery, P. & Wilson, L.J. (2004). The role of industrial fishery and oceanographic change on the decline of North Sea Black-legged Kittiwakes. J. Appl. Ecol. 41: 1129–1139.
  • FSC [=Forest Stewardship Council] (2009). Forest Stewardship Council facts and figures. Available at: http://www.fsc.org/facts-figures.html.
  • Fuller, E. (2002). Extinct birds. Pp. 11–68 in: del Hoyo, J., Elliot, A. & Sargatal, J. eds. (2002). Handbook of the Birds of the World. Vol. 7. Jacamars to woodpeckers. Lynx Edicions, Barcelona.
  • FWI [=Forest Watch Indonesia] & GFW [=Global Forest Watch] (2002). The State of the Forest: Indonesia. Forest Watch Indonesia & Global Forest Watch, Bogor, Indonesia & Washington, D.C.
  • Gallina, S., Mandujano, S. & González-Romero, A. (1996). Conservation of mammalian biodiversity in coffee plantations of central Veracruz, Mexico. Agroforest. Syst. 33: 13–27.
  • García, L., Viada, C., Moreno-Opo, R., Carboneras, C., Alcade, A. & González, F. (2003). Impacto de la Marea Negra del “Prestige” sobre las Aves Marinas. SEO/BirdLife, Madrid.
  • Garnett, S.T. & Crowley, G.M. (2000). The Action Plan for Australian Birds 2000. Environment Australia, Canberra.
  • Gehring, J., Kerlinger, P. & Manville, A.M. (2009). Communication towers, lights, and birds: successful methods of reducing the frequency of avian collisions. Ecol. Appl. 19: 505–514.
  • Gilchrist, H.G. & Mallory, M.L. (2005). Declines in abundance and distribution of the Ivory Gull (Pagophila eburnea) in Arctic Canada. Biol. Conserv. 121: 303–309.
  • Gill, A.M., Woinarski, J.C.Z. & York, A. (1999). Australia’s Biodiversity—Responses to Fire: Plants, Birds and Invertebrates. Department of the Environment and Heritage, Canberra.
  • Goldstein, M.I., Lacher, T.E., Woodbridge, B., Bechard, M.J., Canavelli, S.B., Zaccagnini, M.E., Cobb, G.P., Scollon, E.J., Tribolet, R. & Hooper, M.J. (1999). Monocrotophos - Induced mass mortality of Swainson’s Hawks in Argentina, 1995–96. Ecotoxicology 8: 201–214.
  • Green, A.J. & Hughes, B. (1996). Action plan for the White-headed Duck (Oxyura leucocephala). Pp. 119–145 in: Heredia, B., Rose, L. & Painter, M. eds. (1996). Globally Threatened Birds in Europe: Action Plans. Council of Europe & BirdLife International, Strasbourg & Brussels.
  • Green, R.E. (1998). Long-term decline in the thickness of eggshells of thrushes, Turdus spp., in Britain. Proc. Royal Soc. London (Ser. B Biol. Sci.) 265: 679–684.
  • Green, R.E., Newton, I., Shultz, S., Cunningham, A.A., Gilbert, M., Pain, D. & Prakash, V. (2004). Diclofenac poisoning as a cause of vulture population declines across the Indian subcontinent. J. Appl. Ecol. 41: 793–800.
  • Green, R.E., Cornell, S.J., Scharleman, J.P.W. & Balmford, A. (2005). Farming and the fate of wild nature. Science (Washington, D.C.) 307: 550–555.
  • Greenberg, R., Bichier, P. & Cruz Angón, A. (2000). The conservation value for birds of cacao plantations with diverse planted shade in Tabasco, Mexico. Anim. Conserv. 3: 105–112.
  • Greenwood, J.J.D. (2007). Citizens, science and bird conservation. J. Orn. 148 (Suppl. 1): S77–S124.
  • Gregory, R.D., Noble, D., Field, R., Marchant, J., Raven, M. & Gibbons, D.W. (2003). Using birds as indicators of biodiversity. Ornis Hungarica 12: 11–24.
  • Gregory, R.D., van Strien, A.J., Vorisek, P., Gmelig Meyling, A.W., Noble, D.G., Foppen, R.P.B. & Gibbons, D.W. (2005). Developing indicators for European birds. Phil. Trans. Roy. Soc. London (Ser. B) 360: 269–288.
  • Gregory, R.D., Vorisek, P., van Strien, A.J., Gmelig Meyling, A.W., Jiguet, F., Fornasari, L., Reif, J., Chylarecki, P. & Burfield, I.J. (2007). Population trends of widespread woodland birds in Europe. Ibis 149: 78–97.
  • Gregory, R.D., Vorisek, P., Noble, D.G., van Strien, A.J., Klvanová, A., Eaton, M.E., Gmelig Meyling, A.W., Joys, A., Foppen, R.P.B. & Burfield, I.J. (2008). The generation and use of bird population indicators in Europe. Bird Conserv. Int. 18 (Suppl. 1): S223–S244.
  • Gregory, R.D., Willis, S.G., Jiguet, F., Vorisek, P., Klvanová, A., van Strien, A.J., Huntley, B., Collingham, Y.C., Couvet, D. & Green, R.E. (2009). An indicator of the impact of climatic change on European bird populations. Public Libr. Sci. ONE 4: e4678.
  • Gross, L. (2005). As the Antarctic ice pack recedes, a fragile ecosystem hangs in the balance. Public Libr. Sci. Biol. 3(4): e127.
  • Hames, R.S., Rosenberg, K.V., Lowe, J.D., Barker, S.E. & Dhondt, A.A. (2002). Adverse effects of acid rain on the distribution of the Wood Thrush Hylocichla mustelina in North America. Proc. Natl. Acad. Sci. USA 99: 11235–11240.
  • Hansen, M.C., Stehman, S.V., Potapov, P.V., Loveland, T.R., Townshend, J.R.G., DeFries, R.S., Pittman, K.W., Arunarwati, B., Stolle, F., Steininger, M.K., Carroll, M. & DiMiceli, C. (2008). Humid tropical forest clearing from 2000 to 2005 quantified by using multitemporal and multiresolution remotely sensed data. Proc. Natl. Acad. Sci. USA 105: 9439–9444.
  • Harrison, J.A., Allan, D.G., Underhill, L.G., Herremans, M., Tree, A.J., Parker, V. & Brown, C.J. (1997). The Atlas of Southern African Birds. BirdLife South Africa, Johannesburg.
  • Herremans, M. (1998). Conservation status of birds in Botswana in relation to land use. Biol. Conserv. 86: 139–160.
  • Herremans, M. & Herremans-Tonnoeyr, D. (2000). Land use and the conservation status of raptors in Botswana. Biol. Conserv. 94: 31–41.
  • Hickling, R., Roy, D.B., Hill, J.K., Fox, R. & Thomas, C.D. (2006). The distributions of a wide range of taxonomic groups are expanding polewards. Glob. Change Biol. 12: 450–455.
  • Hickman, M. (2009). The guilty secrets of palm oil: Are you unwittingly contributing to the devastation of the rain forests? The Independent online 2 May 2009. Available at: http://www.independent.co.uk/environment/the-guilty-secrets-of-palm-oil-are-you-unwittingly-contributing-to-the-devastation-of-the-rain-forests-1676218.html.
  • Hirschfeld, A. & Heyd, A. (2005). Mortality of migratory birds caused by hunting in Europe: bag statistics and proposals for the conservation of birds and animal welfare. Ber. Vogelschutz 42: 47–74. In German with English summary.
  • Hitch, A.T. & Leberg, P.L. (2007). Breeding distributions of North American bird species moving north as a result of climate change. Conserv. Biol. 21: 534–539.
  • Hole, D.G., Huntley, B., Pain, D.J., Fishpool, L.D.C., Butchart, S.H.M., Collingham, Y.C., Rahbek, C. & Willis, S.G. (2009). Projected impacts of climate change on a continental-scale protected area network. Ecol. Letters 12: 420–431.
  • Hole, D.G., Huntley, B., Collingham, Y.C., Fishpool, L.D.C., Pain, D.J., Butchart, S.H.M. & Willis, S.G. (2010). Towards a management framework for protected area networks in the face of climate change. MS.
  • Houghton, J.T., Ding, Y., Griggs, D.J., Noguer, M., van der Linden, P.J. & Xiaosu, D. eds. (2001). IPCC Third Assessment Report. Cambridge University Press, Cambridge, UK.
  • Howard, P.C., Viskanic, P., Davenport, T.R.B., Kigenyi, F.W., Baltzer, M., Dickinson, C.J., Lwanga, J.S., Matthews, R.A. & Balmford, A. (1998). Complementarity and the use of indicator groups for reserve selection in Uganda. Nature (London) 394: 472–475.
  • Human Rights Watch (2009). “Wild Money”: the Human Rights Consequences of Illegal Logging and Corruption in Indonesia’s Forestry Sector. Human Rights Watch, New York.
  • Huntley, B., Green, R.E., Collingham, Y.C. & Willis, S.G. (2007). A Climatic Atlas of European Breeding Birds. Durham University, Royal Society for the Protection of Birds & Lynx Edicions, Durham, Sandy & Barcelona.
  • Huntley, B., Collingham, Y.C., Willis, S.G. & Green, R.E. (2008). Potential impacts of climatic change on European breeding birds. Public Libr. Sci. ONE 3(1): e1439.
  • IPCC [=Intergovernmental Panel on Climate Change] (2007). Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Intergovernmental Panel on Climate Change, Geneva, Switzerland.
  • IUCN [=International Union for Conservation of Nature] (2001). IUCN Red List Categories and Criteria. Version 3.1. IUCN Species Survival Commission, Gland, Switzerland & Cambridge, UK.
  • Janss, G.F.E. & Ferrer, M. (2001). Avian electrocution mortality in relation to pole design and adjacent habitat in Spain. Bird Conserv. Int. 11: 3–12.
  • Jarvi, S.I., Atkinson, C.T. & Fleischer, R.C. (2001). Immunogenetics and resistance to avian malaria in Hawaiian honeycreepers (Drepanidinae). Stud. Avian Biol. 22: 254–263.
  • Jeganathan, P., Green, R.E., Bowden, C.G.R., Pain, D. & Rahmani, A. (2002). Use of tracking strips and automatic cameras for detecting critically endangered Jerdon’s Coursers Rhinoptilus bitorquatus in scrub jungle in Andhra Pradesh, India. Oryx 36: 182–188.
  • Jenkins, A.R., Shaw, J.M., Ryan, P.G., Smallie, J.J., Gibbons, B. & Visagie, R. (2010). Power line collisions in Ludwig’s Bustard Neotis ludwigii: measuring rates and modelling demographic effects in the Karoo, South Africa. MS.
  • Jenni, L. & Kéry, M. (2003). Timing of autumn bird migration under climate change: advances in long-distance migrants, delays in short-distance migrants. Proc. Royal Soc. London (Ser. B Biol. Sci.) 270: 1467–1471.
  • Jenouvrier, S., Caswell, H., Barbraud, C., Holland, M., Stroeve, J. & Weimerskirch, H. (2009). Demographic models and IPCC climate projections predict the decline of an Emperor Penguin population. Proc. Natl. Acad. Sci. USA 106: 1844–1847.
  • Jepson, P. & Ladle, R.J. (2009). Governing bird-keeping in Java and Bali: evidence from a household survey. Oryx 43: 364–374.
  • Johns, A.D. (1988). Effects of “selective” timber extraction on rain forest structure and composition and some consequences for frugivores and folivores. Biotropica 20: 31–37.
  • Johnson, M.D., Kellermann, J.L. & Stercho, A.M. (2010). Pest reduction services by birds in shade and sun coffee in Jamaica. Anim. Conserv. 13: 140–147.
  • Johnson, T.H. & Stattersfield, A.J. (1990). A global review of island endemic birds. Ibis 132: 167–180.
  • Kemper, C.A. (1996). A study of bird mortality at a Central Wisconsin TV tower from 1957–1995. Passenger Pigeon 58: 219–235.
  • Kilpatrick, A.M. (2005). Facilitating the evolution of resistance to avian malaria in Hawaiian birds. Biol. Conserv. 128: 475–485.
  • Kingsford, R. & Porter, J. (2008). Wetland health and waterbirds of eastern Australia. Page 14 in: Olsen, P. ed. (2008). The State of Australia’s Birds 2008. Wingspan 18(4) (Supplement). Birds Australia, Victoria.
  • Kleinn, C., Corrales, L. & Morales, D. (2002). Forest area in Costa Rica: a comparative study of tropical forest cover estimates over time. Environm. Monit. Assess. 73: 17–40.
  • Knop, E., Kleijn, D., Herzog, F. & Schmid, B. (2006). Effectiveness of the Swiss agri-environment scheme in promoting biodiversity. J. Appl. Ecol. 43: 120–127.
  • Kock, K.H., Reid, K., Croxall, J.P. & Nicol, S. (2007). Fisheries in the Southern Ocean - an ecosystem approach. Phil. Trans. Roy. Soc. London (Ser. B) 362: 2333–2349.
  • La Pointe, D. (2000). Avian Malaria in Hawaii: the Distribution, Ecology and Vector Potential of Forest-dwelling Mosquitoes. PhD thesis, University of Hawaii, Manoa.
  • La Rouche, G.P. (2009). Birding in the United States: a Demographic and Economic Analysis. U.S. Fish and Wildlife Service, Washington, D.C.
  • La Sorte, F.A. & Thompson, F.R. (2007). Poleward shifts in winter ranges of North American birds. Ecology 88: 1803–1812.
  • Laist, D.W. (1997). Impacts of marine debris: entanglement of marine life in marine debris including a comprehensive list of species with entanglement and ingestion records. Pp. 99–139 in: Coe, J.M. & Rogers, D.B. eds. (1997). Marine Debris: Sources, Impacts, and Solutions. Springer-Verlag, New York.
  • Lambert, F.R. & Collar, N.J. (2002). The future for Sundaic lowland forest birds: long-term effects of commercial logging and fragmentation. Forktail 18: 127–146.
  • Langhammer, P.F., Bakarr, M.I., Bennun, L.A., Brooks, T.M., Clay, R.P., Darwall, W., De Silva, N., Edgar, G.J., Eken, G., Fishpool, L.D.C., da Fonseca, G.A.B., Foster, M.N., Knox, D.H., Matiku, P., Radford, E.A., Rodrigues, A.S.L., Salaman, P., Sechrest, W. & Tordoff, A.W. (2007). Identification and Gap Analysis of Key Biodiversity Areas: Targets for Comprehensive Protected Area Systems. Best Practice Protected Area Guidelines Series 15. IUCN, Gland, Switzerland.
  • Langley, N. (2009). Wings over wetlands. World Birdwatch 31(3): 16–18.
  • Lawton, J.H., Bignell, D.E., Bolton, B., Bloemers, G.F., Eggleton, P., Hammond, P.M., Hodda, M., Holt, R.D., Larsenk, T.B., Mawdsley, N.A., Stork, N.E., Srivastava, D.S. & Watt, A.D. (1998). Biodiversity inventories, indicator taxa and effects of habitat modification in tropical forest. Nature (London) 391: 72–76.
  • LeBaron, G.S. (2009). The 109th Christmas Bird Count. Amer. Birds 63: 2–7.
  • Legra, L., Xingong Li & Peterson, A.T. (2008). Biodiversity consequences of sea level rise in New Guinea. Pacific Conserv. Biol. 14: 191–199.
  • Lekuona, J.M. (2001). Uso del Espacio por la Avifauna y Control de la Mortalidad de Aves y Murciélagos en los Parques Eólicos de Navarra durante un Ciclo Anual. Gobierno de Navarra, Spain.
  • Lemoine, N. & Böhning-Gaese, K. (2003). Potential impact of global climate change on species richness of long-distance migrants. Conserv. Biol. 17: 577–586.
  • Liew, S.C., Lim, O.K., Kwoh, L.K. & Lim, H. (1998). http://www.crisp.nus.edu.sg/~research/research/forest/fire/igars98_fire.... study of the 1997 forest fires in South East Asia using SPOT quicklook mosaics. Proc. 1998 Int. Geosci. Remote Sens. Symposium 2: 879–881.
  • Lindsell, J.A., Serra, G., Peske, L., Abdullah, M.S., al Qaim, G., Kanani, A. & Wondafrash, M. (2009). Satellite tracking reveals the migratory route and wintering area of the Middle East population of Critically Endangered Northern Bald Ibis Geronticus eremita. Oryx 43: 329–335.
  • Løkkeborg, S. (2001). Reducing seabird by-catch in longline fisheries by means of bird-scaring lines and underwater setting. Pp. 33–41 in: Melvin, E.F. & Parrish, J. eds. (2001). Seabird Bycatch: Trends, Roadblocks and Solutions. University of Alaska Sea Grant, Fairbanks, Alaska.
  • Longcore, T., Rich, C. & Gauthreaux, S.A. (2005). Scientific basis to establish policy regulating communications towers to protect migratory birds: response to Avatar Environmental, LLC, report regarding migratory bird collisions with communications towers, WT Docket No. 03-187, Federal Communications Commission Notice of Inquiry. Land Protection Partners, Los Angeles, California.
  • Low, T. (2007). Warming, invasive pests and birds. Page 18 in: Olsen, P. ed. (2007). The State of Australia’s Birds 2007: Birds in a Changing Climate. Wingspan 14(4) (Supplement). Birds Australia, Victoria.
  • Luck, G.W., Ricketts, T.H., Daily, G.C. & Imhoff, M. (2004). Alleviating spatial conflict between people and biodiversity. Proc. Natl. Acad. Sci. USA 101: 182–186.
  • Madeiros, J. (2003). Report on the 2003 Cahow nesting season - another record year! Bermuda Audubon Soc. Newsl. 14: 8–9.
  • Madeiros, J. (2008). Cahow nesting season update April 2008. Bermuda Audubon Soc. Newsl. 19: 2–5.
  • Madroño, A., González, C. & Atienza, J.C. eds. (2004). Libro Rojo de las Aves de España. Dirección General para la Biodiversidad-SEO/BirdLife, Madrid.
  • Magnin, G. (1991). Hunting and persecution of migratory birds in the Mediterranean region. Pp. 63–75 in: Salathé, T. ed. (1991). Conserving Migratory Birds. ICBP Technical Publication 12. International Council for Bird Preservation, Cambridge, UK.
  • Magsalay, P., Brooks, T., Dutson, G.C.L. & Timmins, R. (1995). Extinction and conservation on Cebu. Nature (London) 373: 294.
  • Mallory, M.L., Roberston, G.J. & Moenting, A. (2006). Marine plastic debris in Northern Fulmars from Davis Strait, Nunavut, Canada. Mar. Pollut. Bull. 52: 800–815.
  • Mardas, N., Mitchell, A., Crosbie, L., Ripley, S., Howard, R., Elia, C. & Trivedi, M. (2009). Global Forest Footprints. Forest Footprint Disclosure Project. Global Canopy Programme, Oxford, UK.
  • Markandya, A., Taylor, T., Long, A., Murty, M.N., Murty, S. & Dhavala, K. (2008). Counting the cost of vulture decline - an appraisal of the human health and other benefits of vultures in India. Ecol. Econ. 67: 194–204.
  • Marsden, S.J. (1998). Changes in bird abundance following selective logging on Seram, Indonesia. Conserv. Biol. 12: 605–611.
  • Martyr, D. (1997). Important findings by FFI team in Kerenci Seblat, Sumatra, Indonesia. Oryx 31: 80–82.
  • McCormack, G. (2006). Rimatara Lorikeet reintroduction programme. Available at: http://cookislands.bishopmuseum.org/showarticle.asp?id=24.
  • McGeoch, M.A., Butchart, S.H.M., Spear, D., Marais, E., Kleynhans, E.J., Symes, A., Chanson, J. & Hoffmann, M. (2010). Global indicators of biological invasion: species numbers, biodiversity impact and policy responses. Divers. Distr. 16: 95–108.
  • Mee, A., Rideout, B.A., Hamber, J.A., Todd, N., Austin, G., Clark, M. & Wallace, M.P. (2007). Junk ingestion and nestling mortality in a reintroduced population of California Condors Gymnogyps californianus. Bird Conserv. Int. 17: 119–130.
  • Meretsky, V.J., Snyder, N.F.R., Beissinger, S.R., Clendenen, D.A. & Wiley, J.W. (2000). Demography of the California Condor: implications for reestablishment. Conserv. Biol. 14: 957–967.
  • Millennium Ecosystem Assessment (2005). Ecosystems and Human Well-being: Synthesis. Island Press, Washington, D.C.
  • Mineau, P. (2009). Birds and pesticides: is the threat of a silent spring really behind us? Pesticide News 86: 12–18.
  • Mineau, P., Fletcher, M.R., Glaser, L.C., Thomas, N.J., Brassard, C., Wilson, L.K., Elliott, J.E., Lyons, L.A., Henny, C.J. & Bollinger, T. (1999). Poisoning of raptors with organophosphorus and carbamate pesticides with emphasis on Canada, U.S. & U.K. J. Raptor Res. 33: 1–37.
  • Moline, M.A., Claustre, H., Frazer, T.K., Schofield, O. & Vernet, M. (2004). Alteration of the food web along the Antarctic Peninsula in response to a regional warming trend. Global Change Biol. 10: 1973–1980.
  • Møller, A.P. & Mousseau, T.A. (2006). Biological consequences of Chernobyl: 20 years on. Trends Ecol. Evol. 21: 200–207.
  • Møller, A.P., Rubolini, D. & Lehikoinen, E. (2008). Populations of migratory bird species that did not show a phenological response to climate change are declining. Proc. Natl. Acad. Sci. USA 105: 16195–16200.
  • Mols, C.M.M. & Visser, M.E. (2002). Great Tits can reduce caterpillar damage in apple orchards. J. Appl. Ecol. 39: 888–899.
  • Moseikin, V.N. (2003). The operation and construction of fatal power lines continues in Russia and Kazakhstan. Poster presentation at the Sixth World Conference on Birds of Prey and Owls, 18–23 May 2003, Budapest, Hungary.
  • Moser, M.L. & Lee, D.S. (1992). A fourteen-year survey of plastic ingestion by western North Atlantic seabirds. Colonial Waterbirds 15: 83–94.
  • Mulliken, T.A., Broad, S.R. & Thomsen, J.B. (1992). The wild bird trade—an overview. Pp. 1–41 in: Thomsen, J.B., Edwards, S.R. & Mulliken, T.A. eds. (1992). Perceptions, Conservation and Management of Wild Birds in Trade. TRAFFIC International, Cambridge, UK.
  • Mwangi, M.A.K., Butchart, S.H.M., Barasa, F., Bennun, L.A., Evans, M.I., Fishpool, L.D.C., Kanyanya, E., Madindou, I., Machekele, J., Matiku, P., Mulwa, R., Ngari, A., Stattersfield, A.J. & Siele, J. (2010). Tracking trends in key sites for biodiversity: a case study using Important Bird Areas in Kenya. MS.
  • Nabhan, G.P. & Buchmann, S.L. (1997). Services provided by pollinators. Pp. 133–150 in: Daily, G. ed. (1997). Nature’s Services: Societal Dependence on Natural Ecosystems. Island Press, Washington, D.C.
  • Naidoo, V., Wolter, K., Cromarty, D., Diekmann, M., Duncan, N., Meharg, A.A., Taggart, M.A., Venter, L. & Cuthbert, R. (2010). Toxicity of non-steroidal anti-inflammatory drugs to Gyps vultures: a new threat from ketoprofen. Biol. Letters (London) 6: 339–341.
  • Natsagdorj, T. & Batbayar, N. (2002). The impact of rodenticide used to control rodents on Demoiselle Crane (Anthropoides virgo) and other animals in Mongolia. Unpubl. report.
  • Newson, S.E., Mendes, S., Crick, H.Q.P., Dulvy, N.K., Houghton, J.D.R., Hays, G.C., Hutson, A.M., Macleod, C.D., Pierce, G.J. & Robinson, R.A. (2008). Indicators of the impact of climate change on migratory species. Endangered Species Res. 7: 101–113.
  • Niemuth, N.D., Quamen, F.R., Naugle, D.E., Reynolds R.E., Estey, M.E. & Shaffer, T.L. (2007). Benefits of the conservation reserve program to grassland bird populations in the Prairie Pothole Region of North Dakota and South Dakota. Report for the United States Department of Agriculture Farm Service Agency. Available at: http://www.fsa.usda.gov/Internet/FSA_File/grassland_birds_fws.pdf.
  • Niven, D.K., Butcher, G.S., Bancroft, G.T., Monaghan, W.B. & Langham, G. (2009). Birds and Climate Change: Ecological Disruption in Motion. National Audubon Society, New York.
  • Oaks, J.L., Gilbert, M., Virani, M.Z., Watson, R.T., Meteyer, C.U., Rideout, B.A., Shivaprasad, H.L., Ahmed, S., Chaudhry, M.J.I., Arshad, M., Mahmood, S., Ali, A. & Khan, A.A. (2004). Diclofenac residues as the cause of vulture population decline in Pakistan. Nature (London) 427: 630–633.
  • O’Brien, T.G. & Kinnaird, M.F. (2003). Caffeine and conservation. Science (Washington, D.C.) 300: 587.
  • O’Brien, T.G. & Kinnaird, M.F. (2008). A picture is worth a thousand words: the application of camera trapping to the study of birds. Bird Conserv. Int. 18: S144–S162.
  • Olsen, P. ed. (2008). The State of Australia’s Birds 2008. Wingspan 18(4) (Supplement). Birds Australia, Victoria.
  • Olson, S.L. & James, H.F. (1982). Fossil birds from the Hawaiian Islands: evidence for wholesale extinction by man before Western contact. Science (Washington, D.C.) 217: 633–635.
  • Orris, P., Chary, L.K., Perry, K. & Asbury, J. (2000). Persistent Organic Pollutants and Human Health. World Federation of Public Health Associations, Washington, D.C.
  • Page, S.E., Siegert, F., Rieley, J.O., Boehm, H.D.V., Jaya, A. & Limin, S. (2002). The amount of carbon released from peat and forest fires in Indonesia during 1997. Nature (London) 420: 61–65.
  • Pain, D.J., Meharg, A.A., Ferrer, M., Taggart, M. & Penteriani, V. (2005a). Lead concentrations in bones and feathers of the globally threatened Spanish Imperial Eagle. Biol. Conserv. 121: 603–610.
  • Pain, D.J., Fishpool, L.D.C., Byaruhanga, A., Arinaitwe, J. & Balmford, A. (2005b). Biodiversity representation in Uganda’s forest IBAs. Biol. Conserv. 125: 133–138.
  • Pain, D.J., Bowden, C.G.R., Cunningham, A.A., Cuthbert, R., Das, D., Gilbert, M., Jakati, R.D., Jhala, Y., Khan, A.A., Naidoo, V., Oaks, J.L., Parry-Jones, J., Prakash, V., Rahmani, A., Ranade, S.P., Baral, H.S., Senacha, K.R. & Saravanan, S. (2008). The race to prevent the extinction of South Asian vultures. Bird Conserv. Int. 18: S30–S48.
  • Parmesan, C. & Yohe, G. (2003). A globally coherent fingerprint of climate change impacts across natural systems. Nature (London) 421: 37–42.
  • Paton, D. & Rogers, D. (2008). Mallee Emu-wren: South Australia. Page 35 in: Olsen, P. ed. (2008). The State of Australia’s Birds 2008. Wingspan 18(4) (Supplement). Birds Australia, Victoria.
  • Pauly, D. & Watson, R. (2005). Background and interpretation of the ‘Marine Trophic Index’ as a measure of biodiversity. Phil. Trans. Roy. Soc. London (Ser. B) 360: 415–423.
  • Pauly, D., Christensen, V., Dalsgaard, J., Froese, R. & Torres, F. (1998). Fishing down marine food webs. Science (Washington, D.C.) 279: 860–863.
  • Pearson, D.L. (1995). Selecting indicator taxa for the quantitative assessment of biodiversity. Pp. 75–80 in: Hawksworth, D.L. ed. (1995). Biodiversity: Measurement and Estimation. Chapman and Hall & The Royal Society, London.
  • PECBMS [=Pan-European Common Bird Monitoring Scheme] (2009). The State of Europe’s Common Birds, 2008. Czech Society for Ornithology/Royal Society for the Protection of Birds, Prague.
  • Perfecto, I., Rice, R.A., Greenberg, R. & van der Voort, M.E. (1996). Shade coffee: a disappearing refuge for biodiversity. BioScience 46: 598–608.
  • Peterson, A.T., Komar, N., Komar, O., Navarro-Sigüenza, A., Robbins, M.B. & Martínez-Meyer, E. (2004). West Nile virus in the New World: potential impacts on bird species. Bird Conserv. Int. 14: 215–232.
  • Petry, M.V., da Silva Fonesca, V.S. & Scherer, A.L. (2007). Analysis of stomach contents from the Black-browed Albatross, Thalassarche melanophris, on the coast of Rio Grande do Sul, Southern Brazil. Polar Biol. 30: 321–325.
  • Poncet, S., Robertson, G., Phillips, R.A., Lawton, K., Phalan, B., Trathan, P.N. & Croxall, J.P. (2006). Status and distribution of Wandering, Black-browed and Grey-headed Albatrosses breeding at South Georgia. Polar Biol. 29: 772–781.
  • Pounds, J.A., Fogen, M.P.L. & Campbell, J.H. (1999). Biological response to climate change on a tropical mountain. Nature (London) 398: 611–615.
  • Prakash, V., Green, R.E., Pain, D.E., Ranade, S.P., Saravanan, S., Prakash, N., Venkitachalam, R., Cuthbert, R., Rahmani, A.R. & Cunningham, A.A. (2007). Recent changes in populations of resident Gyps vultures in India. J. Bombay Nat. Hist. Soc. 104: 129–135.
  • Probst, J.R., Donner, D.M., Bocetti, C.I. & Sjogren, S. (2003). Population increase in Kirtland’s Warbler and summer range expansion to Wisconsin and Michigan’s Upper Peninsula, U.S.A. Oryx 37: 365–373.
  • Purvis, A., Agapow, P.M., Gittleman, J.L. & Mace, G.M. (2000). Nonrandom extinction and the loss of evolutionary history. Science (Washington, D.C.) 288: 328–330.
  • Reitsma, R., Parrish, J.D. & McLarney, W. (2001). The role of cacao plantations in maintaining forest avian diversity in southeastern Costa Rica. Agroforest. Syst. 53: 185–193.
  • Richardson, C.J. & Hussain, N.A. (2006). Restoring the Garden of Eden: an ecological assessment of the marshes of Iraq. BioScience 56: 477–489.
  • Ricketts, T.H., Dinerstein, E., Boucher, T., Brooks, T.M., Butchart, S.H.M., Hoffmann, M., Lamoreux, J.F., Morrison, J., Parr, M., Pilgrim, J.D., Rodrigues, A.S.L., Sechrest, W., Wallace, G.E., Berlin, K., Bielby, J., Burgess, N.D., Church, D.R., Cox, N., Knox, D., Loucks, C., Luck, G.W., Master, L.L., Moore, R., Naidoo, R., Ridgely, R., Schatz, G.E., Shire, G., Strand, H., Wettengel, W. & Wikramanayake, E. (2005). Pinpointing and preventing imminent extinctions. Proc. Natl. Acad. Sci. USA 51: 18497–18501.
  • van Riper, C. & Scott, J.M. (2001). Limiting factors affecting Hawaiian native birds. Stud. Avian Biol. 22: 221–233.
  • Robertson, H.A. & Saul, E.K. (2007). Conservation of Kakerori (Pomarea dimidiata) in the Cook Islands in 2005/06. DOC Research & Development Series 285. Department of Conservation, Wellington, New Zealand.
  • Robertson, H.A., Hay, J.R., Saul, E.K. & McCormack, G.V. (1994). Recovery of the Kakerori: an endangered forest bird of the Cook Islands. Conserv. Biol. 8: 1078–1086.
  • Robertson, G., McNeill, M., Smith, N., Wienece, B., Candy, S. & Olivier, F. (2006). Fast sinking (integrated weight) longlines reduce mortality of White-chinned Petrels (Procellaria aequinoctialis) and Sooty Shearwaters (Puffinus griseus) in demersal longline fisheries. Biol. Conserv. 132: 458–471.
  • Rodrigues, A.S.L. (2007). Effective global conservation strategies. Nature (London) DOI: 10.1038/nature06374.
  • Root, T.L., Price, J.T., Hall, K.R., Schneider, S.H., Rosenzweig, C. & Pounds, J.A. (2003). Fingerprints of global warming on wild animals and plants. Nature (London) 421: 57–60.
  • RSPB [=Royal Society for the Protection of Birds] (2008). Big Garden Birdwatch 2008 results are out. Available at: http://www.rspb.org.uk/news/details.asp?id=tcm:9-186314.
  • Rubolini, D., Gustin, M., Bogliani, G. & Garavaglia, R. (2005). Birds and powerlines in Italy: an assessment. Bird Conserv. Int. 15: 131–145.
  • Ryan, P.G. (1987). The effects of ingested plastic on seabirds: correlations between plastic load and body condition. Environm. Pollut. 46: 119–125.
  • Ryan, P.G. (2003). Estimating the demographic benefits of rehabilitating oiled African Penguins. Pp. 25–29 in: Nel, D.C. & Whittington, P.A. eds. (2003). Rehabilitation of Oiled African Penguins: a Conservation Success Story. BirdLife South Africa & Avian Demography Unit, Cape Town.
  • Rytkönen, A. (2003). Market access of forest goods and services. A background paper for the global project: Impact Assessment of Forest Products Trade in Promotion of Sustainable Forest Management, GCP/INT/775/JPN. Food and Agriculture Organization, Rome. Available at: www.fao.org/forestry/foris/data/trade/pdf/rytkonen.pdf.
  • Sachet, M.H. (1962). Flora and vegetation of Clipperton Island. Proc. California Acad. Sci. Ser. 4, no. 31(10): 249–307.
  • Saino, N., Rubolini, D., Lehikoinen, E., Sokolov, L.V., Bonisoli-Alquati, A., Ambrosini, R., Boncoraglio, G. & Møller, A.P. (2009). Climate change effects on migration phenology may mismatch brood parasitic cuckoos and their hosts. Biol. Letters (London) 5: 539–541.
  • Salafsky, N., Salzer, D., Stattersfield, A.J., Hilton-Taylor, C., Neugarten, R., Butchart, S.H.M., Collen, B., Cox, N., Master, L.L., O’Connor, S. & Wilkie, D. (2008). A standard lexicon for biodiversity conservation: unified classifications of threats and actions. Conserv. Biol. 22: 897–911.
  • Sanderson, F.J., Donald, P.F., Pain, D.J., Burfield, I.J. & van Bommel, F.P.J. (2006). Long-term population declines in Afro-Palearctic migrant birds. Biol. Conserv. 131: 93–105.
  • Saunders, D.L. & Tzaros, C.L. (2009). Draft national recovery plan for the Swift Parrot Lathamus discolor. Report to the Department of the Environment, Water, Heritage and the Arts, Canberra, New South Wales Department of Environment and Climate Change and Water & Birds Australia, Queanbeyan & Melbourne.
  • Schelhas, J. & Greenberg, R.S. eds. (1996). Forest Patches in Tropical Landscapes. Island Press, Washington, D.C.
  • Searchinger, T., Heimlich, R., Houghton, R.A., Dong, F., Elobeid, A., Fabiosa, J., Tokgoz, S., Hayes, D. & Yu, T.H. (2008). Use of U.S. croplands for biofuels increases greenhouse gases through emissions from land-use change. Science (Washington, D.C.) 319: 1238–1240.
  • Sekercioglu, C.H. (2006). Ecological significance of bird populations. Pp.15–51 in: del Hoyo, J., Elliot, A. & Christie, D.A. eds. (2006). Handbook of the Birds of the World. Vol. 11. Old World flycatchers to Old World warblers. Lynx Edicions, Barcelona.
  • Serra, G. (2003). The discovery of Northern Bald Ibises in Syria. World Birdwatch 25: 10–13.
  • Sharam, G.J., Sinclair, A.R.E. & Turkington, R. (2009). Serengeti birds maintain forests by inhibiting seed predators. Science (Washington, D.C.) 325: 51.
  • Shire, G.G., Brown, K. & Winegrad, G. (2000). Communication towers: a deadly hazard to birds. Report compiled by American Bird Conservancy. Available at: http://www.abcbirds.org/newsandreports/towerkillweb.pdf.
  • Shultz, S., Baral, H.S., Charman, S., Cunningham, A.A., Das, D., Ghalsasi, G.R., Goudar, M.S., Green, R.E., Jones, A., Nighot, P., Pain, D.J. & Prakash, V. (2004). Diclofenac poisoning is widespread in declining vulture populations across the Indian subcontinent. Proc. Royal Soc. London (Ser. B Biol. Sci.) 271 (Suppl. 6): S458–S460.
  • Silcocks, A. & Sanderson, C. (2007). Volunteers monitoring change: the atlas of Australian birds. Page 10 in: Olsen, P. ed. (2007). The State of Australia’s Birds 2007: Birds in a Changing Climate. Wingspan 14(4) (Supplement). Birds Australia, Victoria.
  • Sims, L. & Narrod, C. (2008). Understanding Avian Influenza – a Review of the Emergence, Spread, Control, Prevention and Effects of Asian-lineage H5N1 Highly Pathogenic Viruses. Food and Agriculture Organization of the United Nations, Rome.
  • Small, C.J. (2005). Regional Fisheries Management Organisations: Their Duties and Performance in Reducing Bycatch of Albatrosses and Other Species. BirdLife International, Cambridge, UK.
  • Smith, G.T. (1985). Population and habitat selection of the Noisy Scrub-bird, Atrichornis clamosus, 1962–83. Austr. Wildl. Res. 12: 479–485.
  • Stanners, D. & Bourdeau, P. eds. (1995). Europe’s Environment: the Dobris Assessment. European Environment Agency, Copenhagen.
  • Stattersfield, A.J., Crosby, M.J., Long, A.J. & Wege, D.C. (1998). Endemic Bird Areas of the World: Priorities for Biodiversity Conservation. BirdLife International, Cambridge, UK.
  • Steadman, D.W. (1995). Prehistoric extinctions of Pacific island birds: biodiversity meets zooarchaeology. Science (Washington, D.C.) 267: 1123–1131.
  • Stewart, G.B., Pullin, A.S. & Coles, C.F. (2005). Effects of wind turbines on bird abundance. Summary report, Centre for Evidence-based Conservation Systematic Review 4. Available at:
  • www.environmentalevidence.org/Documents/Summary-SR4.pdf.
  • Still, C.J., Foster, P.N. & Schneider, S. (1999). Simulating the effects of climate change on tropical montane cloud forests. Nature (London) 398: 608–610.
  • Swaddle, J.P. & Calos, S.E. (2008). Increased avian diversity is associated with lower incidence of human West Nile infection: observation of the dilution effect. Public Libr. Sci. ONE 3(6): e2488. DOI: 10.1371/journal.pone.0002488.
  • Takekawa, J.Y. & Garton, E.O. (1984). How much is an Evening Grosbeak worth? J. Forestry 82: 426–428.
  • TEEB [=The Economics of Ecosystems and Biodiversity] (2008). The economics of ecosystems and biodiversity: an interim report. European Commission, Brussels.
  • Thiollay, J.M. (1992). Influence of selective logging on bird species diversity in a Guianan rain forest. Conserv. Biol. 6: 47–63.
  • Thiollay, J.M. (1997). Disturbance, selective logging and bird diversity: a Neotropical forest study. Biodiv. Conserv. 6: 1155–1173.
  • Thiollay, J.M. (2006a). The decline of raptors in West Africa: long-term assessment and the role of protected areas. Ibis 148: 240–254.
  • Thiollay, J.M. (2006b). Severe decline of large birds in the Northern Sahel of West Africa: a long-term assessment. Bird Conserv. Int. 16: 353–365.
  • Thiollay, J.M. (2007a). Raptor declines in West Africa: comparisons between protected, buffer and cultivated areas. Oryx 41: 322–329.
  • Thiollay, J.M. (2007b). Raptor population decline in West Africa. Ostrich 78: 405–413.
  • Thomas, C.D. & Lennon, J.J. (1999). Birds extend their ranges northwards. Nature (London) 399: 213.
  • Thomas, R. (2005). Migrant birds: carriers of disease or convenient scapegoats? World Birdwatch 27(4): 9–12.
  • Thorsen, M. & Jones, C. (1998). The conservation status of Echo Parakeet Psittacula eques of Mauritius. Bull. Afr. Bird Club 5: 122–126.
  • Tiller, C. & Danks, A. (2008). Noisy Scrub-bird, Western Bristlebird and Western Whipbird. Page 34: in Olsen, P. ed. (2008). The State of Australia’s Birds 2008. Wingspan 18(4) (Supplement). Birds Australia, Victoria.
  • Times of India (2008). Birds and us. Available at: http://timesofindia.indiatimes.com/Opinion/Editorial/Birds_and_Us/articleshow/2744333.cms.
  • Torres Esquivias, J.A. (2003). La población española de Malvasía Cabeciblanca (Oxyura leucocephala) venticinco años después del mínimo de 1977. Oxyura 11: 5–33.
  • Traill, L.W., Brook, B.W., Frankham, R.R. & Bradshaw, C.J.A. (2009). Pragmatic population viability targets in a rapidly changing world. Biol. Conserv.143: 28–34.
  • Turner, J., Colwell, S.R., Marshall, G.J., Lachlan-Cope, T.A., Carleton, A.M., Jones, P.D., Lagun, V., Reid, P.A. & Iagovkina, S. (2005). Antarctic climate change during the last 50 years. Int. J. Climatol. 25: 279–294.
  • UN [=United Nations] (2008). World population prospects: the 2008 revision. Available at: http://esa.un.org/unpd/wpp2008/pdf/WPP2008_Executive-Summary_Edited_6-Oct-2009.pdf.
  • UNEP [=United Nations Environment Programme] (2002). Global Environment Outlook 3. Earthscan, London.
  • UNEP [=United Nations Environment Programme] (2005). Marine litter: an analytical overview. Available at: http://www.unep.org/regionalseas/marinelitter/publications/docs/anl_oview.pdf.
  • US NABCI [=United States North American Bird Conservation Initiative] Committee (2009). State of the Birds 2009: United States of America. U.S. Dept. Interior, Washington, D.C.
  • USFWS [=United States Fish and Wildlife Service] (2002). Migratory bird mortality. U.S. Fish and Wildlife Service, Arlington, Virginia. Available at: http://birds.fws.gov/mortality-fact-sheet.pdf.
  • USFWS [=United States Fish and Wildlife Service] (2003a). Birding in the United States: a Demographic and Economic Analysis. Division of Federal Aid, Washington, D.C.
  • USFWS [=United States Fish and Wildlife Service] (2003b). Draft revised recovery plan for the Alala (Corvus hawaiiensis). U.S. Fish and Wildlife Service, Portland, Oregon. Available at: http://ecos.fws.gov/docs/recovery_plans/2003/031218b.pdf.
  • USGS [=United States Geological Survey] (2010). How many birds are banded? Available at: http://www.pwrc.usgs.gov/BBL/homepage/howmany.cfm.
  • Veit, R.R., McGowan, J.A., Ainley, D.G., Wahl, T.R. & Pyle, P. (1997). Apex marine predator declines 90% in association with changing oceanic climate. Global Change Biol. 3: 23–28.
  • Verweij, P., Schouten, M., van Beukering, P., Triana, J., van der Leeuw, K. & Hess, S. (2009). Keeping the Amazon Forests Standing: a Matter of Values. WWF-Netherlands, Zeist, The Netherlands.
  • Vié, J.C., Hilton-Taylor, C. & Stuart, S.N. eds. (2008). The 2008 Review of the IUCN Red List of Threatened Species. IUCN, Gland, Switzerland.
  • Virkkala, R., Heikkinen, R.K., Leikola, N. & Luoto, M. (2008). Projected large-scale range reductions of northern-boreal land bird species due to climate change. Biol. Conserv. 141: 1343–1353.
  • Visser, M.E., van Noordwijk, A.J., Tinbergen, J.M. & Lessells, C.M. (1998). Warmer springs lead to mistimed reproduction in Great Tits (Parus major). Proc. Royal Soc. London (Ser. B Biol. Sci.) 265: 1867–1870.
  • Wallace, M. (2005). Re-introduction of the California Condor to Baja California, Mexico. Re-introduction News 24: 27–28.
  • Wanless, R.M., Angel, A., Cuthbert, R.J., Hilton, G.M. & Ryan, P.G. (2007). Can predation by invasive mice drive seabird extinctions? Biol. Letters (London) 3: 241–244.
  • Watkins, B.P., Petersen, S.L. & Ryan, P.G. (2008). Interactions between seabirds and deep-water hake trawl gear: an assessment of impacts in South African waters. Anim. Conserv. 11: 247–254.
  • Watson, J., Warman, C., Todd, D. & Laboudallon, V. (1992). The Seychelles Magpie Robin Copsychus sechellarum: ecology and conservation of an endangered species. Biol. Conserv. 61: 93–106.
  • Weimerskirch, H. (2004). Disease outbreak threatens Southern Ocean albatrosses. Polar Biol. 27: 374–379.
  • Werner, O. & Harder, T.C. (2006). Chapter 2: Avian Influenza. Pp. 48–86 in: Kamps, B.S., Hoffman, C. & Preiser, W. eds. (2006). Influenza Report. Flying Publisher, Paris.
  • Westcott, S. (2007). Studies show CRP supports millions of ducks and grassland birds in Prairie Pothole Region. USDA Press release (9 May 2007) available at: http://www.fsa.usda.gov/FSA/newsReleases?area=newsroom&subject=landing&t... nr_20070509_rel_1448.html.
  • Whittington, P.A. (2003). Post-release survival of rehabilitated African Penguins. Pp. 8–17 in: Nel, D.C. & Whittington, P.A. eds. (2003). Rehabilitation of Oiled African Penguins: a Conservation Success Story. BirdLife South Africa & Avian Demography Unit, Cape Town.
  • WHO [=World Health Organization] (2008). Responses to Avian Influenza and State of Pandemic Readiness. Fourth Global Progress Report. United Nations System Influenza Coordination & World Bank, New York &Washington, D.C.
  • Williams, A.J. & Ward, V.L. (2002). Catastrophic cholera: coverage, causes, context, conservation and concern. Bird Numbers 11: 2–6.
  • Williams, S.E., Bolitho, E.E. & Fox, S. (2003). Climate change in Australian tropical rainforests: an impending environmental catastrophe. Proc. Royal Soc. London (Ser. B Biol. Sci.) 270: 1887–1892.
  • Williams, T. (1997). Silent scourge: legal pesticides continue to kill millions of our birds. Audubon 99(1): 28–35.
  • Wilson, J.D., Evans, J., Browne, S.J. & King, J.R. (1997). Territory distribution and breeding success of Skylarks Alauda arvensis on organic and intensive farmland in Southern England. J. Appl. Ecol. 34: 1462–1478.
  • Wolff, A., Paul, J.P., Martin, J.L. & Bretagnolle, V. (2001). The benefits of extensive agriculture to birds: the case of the Little Bustard. J. Appl. Ecol. 38: 963–975.
  • World Bank (2004). Sustaining Forests: a Developmental Strategy. World Bank, Washington, D.C.
  • World Commission on Dams (2000). Dams and Development: a New Framework for Decision-making. Earthscan, London.
  • Wotton, S.R. & Peach, W.J. (2007). Population Changes and Summer Habitat Associations of Breeding Cirl Buntings Emberiza cirlus and Other Farmland Birds in Relation to Measures Provided Through the Countryside Stewardship Scheme in Devon, England. Royal Society for the Protection of Birds, Sandy, UK.
  • Wunderle, J.M. & Latta, S.C. (1996). Avian abundance in sun and shade coffee plantations and remnant pine forest in the Cordillera Central, Dominican Republic. Orn. Neotropical 7: 19–34.
  • Yang Liu, Holt, P.I., Lei Jinyu, Zhang Yu & Zhang Zhengwang (2006). Distribution, numbers and age structure of Relict Gull Larus relictus in Bohai Bay, China. Waterbirds 29: 375-380.
  • Yu, Y.T. (2003). International Black-faced Spoonbill Census: 24–26 January 2003. Hong Kong Bird Watching Society, Hong Kong.
  • Zöckler, C. (1998). Patterns in Biodiversity in Arctic Birds. World Conservation Monitoring Centre WCMC, Cambridge, UK.
  • Zöckler, C. & Lysenko, I. (2000). Water Birds on the Edge: First Circumpolar Assessment of Climate Change Impact on Arctic Breeding Water Birds. World Conservation Press, Cambridge, UK.
  • Zöckler, C., Syroechkovski, E.E. & Bunting, G.C. (2008). International Action Plan for the Spoon-billed Sandpiper. BirdLife International Asia, Tokyo.
  • Zöckler, C., Htin Hla, T., Clark, N., Syroechkovskiy, E., Yakushev, N., Daengphayon, S. & Robinson, R. (2010). Hunting in Myanmar is probably the main cause of the decline of the Spoon-billed Sandpiper Calidris pygmeus. Wader Study Group Bull. 117: 1–8.


All WebPages accessed April 2010.