HBW16 - Species Accounts: Blue-grey Tanager (Thraupis episcopus)

Genus THRAUPIS Boie, 1826

65. Blue-grey Tanager

Thraupis episcopus

French: Tangara évêque

German: Bischofstangare

Spanish: Tangara Azuleja

Other common names: Blue Tanager (when treated as conspecific withT. sayaca)

Taxonomy. Tanagra Episcopus Linnaeus, 1766, probably Cayenne, French Guiana.

Formerly known under name ofT. virens, but present name given priority.Recent molecular-genetic data do not support the monophyly of genus as currently constituted, with six of eight species sampled embedded with Tangara, a finding that makes genus Tangara paraphyletic; further research required. This species may form a superspecies withT. sayaca andT. glaucocolpa; replaced by former S of Amazonia.Sometimes considered conspecific with one or both of those, but believed to differ vocally from T. sayaca and differs markedly from T. glaucocolpa in plumage, voice and habitat; extent, if any, to which race boliviana of T. sayaca overlaps with present species, with which it shares some plumage features (e.g. white on shoulder), in N Bolivia requires investigation. Some geographical variation within present species significant, but several races only slightly different and seem hardly worthy of recognition; review of the various races seems warranted. Proposed raceehrenreichi (described from R Purús, in N Brazil) synonymized with coelestis. Thirteen subspecies provisionally recognized.

Subspecies and Distribution.

T. e. cana (Swainson, 1834) - SE Mexico (from extreme SE San Luis Potosí­) S through Central America, including Pearl Is (off S Panama), to Colombia W of E Andes, Caribbean coast and N Venezuela (E to Sucre and Monagas).

T. e. caesitia Wetmore, 1959 - I Escudo de Veraguas (Bocas del Toro), off NW Panama.

T. e. cumatilis Wetmore, 1957 -Coiba I, off SW Panama.

T. e. nesophilus Riley, 1912 - extreme NE Colombia, S & E Venezuela, and Trinidad.

T. e. berlepschi (Dalmas, 1900) - Tobago.

T. e. quaesita Bangs & Noble, 1918 - SW Colombia (W Nariño) S on Pacific slope to NW Peru.

T. e. leucoptera (P. L. Sclater, 1886) - E slope of Andes in Colombia (Cundinamarca and Meta).

T. e. mediana J. T. Zimmer, 1944 - E Colombia, extreme S Venezuela (S Amazonas, S Bolí­var) and N Brazil (E to R Jamundá, and S of Amazon between R Madeira and Tapajós) S to N Bolivia.

T. e. coelestis (Spix, 1825) - SE Colombia, W Brazil (E to R Negro and R Madeira) and NE Ecuador S to C Peru.

T. e. episcopus (Linnaeus, 1766) - the Guianas, and N Brazil E of R Jamundá to NW Maranhão, and S to SE Pará and N Mato Grosso.

T. e. caerulea J. T. Zimmer, 1929 - SE Ecuador and N Peru (S to Huánuco).

T. e. major (Berlepsch & Stolzmann, 1896) - Chanchamayo Valley, in C Peru.

T. e. urubambae J. T. Zimmer, 1944 - Urubamba Valley and Amazonian drainage, in SE Peru.

Descriptive notes. 16 cm; 27-45 g.A pale grey and blue tanager with rather short, stout bill. Nominate race has entire head and underparts pale grey, upperparts slightly darker bluish-grey and contrasting with paler head; central tail feathers dull blue, outer feathers with progressively less blue, outermost pair edged blue; upperwing-coverts dark bluish with paler whitish edges, marginal and lesser coverts white; flight-feathers dusky, edged bright blue to turquoise-blue; iris reddish-brown; bill mostly dusky black, narrow base of upper mandible and all except tip of lower mandible blue-grey; legs horn-grey. Sexes similar. Immature is much duller than adult, often lacks contrast between head and back, and has shoulders and wing-coverts greyish. Races differ mainly in relative amounts of blue and grey shading in plumage, also in colour of upperwing-coverts, those in N & W of range having coverts pale blue to dark cobalt-blue, races in W & C Amazonia and upper Orinoco region having shoulders white to bluish-white and often additional a white wingbar (white tips of greater coverts) and prominent blue edging on tail: cana has ultramarine-blue lesser wing-coverts (usually hidden), dusky median coverts broadly edged dull blue, dusky greater coverts edged pale blue, primary coverts dark blue, flight-feathers prominently edged bright blue, outer half of each tertial feather dull blue, female similar but slightly duller, with edging on flight-feathers lighter blue; caesitia is like previous but darker, particularly below, where uniform from throat to undertail-coverts except for darker sides; cumatilis is slightly smaller than last, like cana but sides and flanks darker blue, underwing-coverts (especially outer ones) darker; quaesita is very like cana, but male has greater wing-coverts, primary coverts, and edging on flight-feathers and tertials bluish-green (not blue), female has wing-covert and primary edgings duller blue; nesophilus has lesser and median coverts concolorous with back; berlepschi is brighter overall, with darker blue on rump and lesser wing-coverts; coelestis has head, mantle, back, rump and underparts slightly more bluish grey than others, uppertail-coverts pale bluish-white, tail dull blue with dusky outermost feathers narrowly to broadly edged blue, lesser and median wing-coverts white, greater coverts dull cerulean-blue with prominent white tips (single white wingbar), primary coverts dark blue, flight-feathers dusky, edged blue, tertials with outer half of feather dull blue and rounded tip whitish, female similar to male but greater coverts brighter blue and flight-feather edgings paler (brighter) blue; leucoptera has shoulder and lesser and median wing-coverts white, somewhat suffused or mixed greyish-blue, greater coverts with only faint whitish tips (no obvious wingbar), both sexes with flight-feather edgings lighter blue; mediana most closely resembles previous, including whitish shoulder and lesser and median wing coverts somewhat mixed with blue gray but differs in both sexes having the greater wing coverts prominently edged white and with the flight feathers and tail prominently edged blue (similar to coelestis and darker than leucoptera); caerulea has lesser and median wing-coverts white, greater coverts tipped white, is closest to coelestis and major and of same size, but purer blue than either; major is similar to previous, but paler; urubambae is very like last, but top of head paler and duller, and wingbar on average not so clearly white. Voice. Song, by both sexes (apparently briefer and weaker by female), a complex series of squeaky and twittering notes, pattern individually and perhaps geographically variable, but typically mixed with strained "tsuee" and "tsuup" notes; sometimes two birds, or mated partners, sing simultaneously, resulting in a jumble of notes; regional dialects reported, but in all areas song rather similar to that ofT. pamarum. Commonest calls a rising "seeeee" and a dry, strained "tsuup", sometimes followed by a few twittery or squeaky notes.

Habitat. Broad spectrum of essentially non-forest habitats, including all kinds of settled areas, plantations, city parks, gardens, young to old second growth, forest borders, savannas with scattered trees, waste areas and margins of rivers and lakes in dry to humid regions; everywhere thrives in man-altered habitats and, in addition to using crevices in building as nest-sites, sometimes roosts in crevices or beams in building. Rare or absent from arid regions in Central America, and partly to mostly replaced byT. glaucocolpa in arid zones along Caribbean coast of Colombia and Venezuela. Sea-level to c. 2700 m, mostly below c. 1800 m; locally to 2000 m in Urubamba Valley of Peru.

Food and Feeding. Mostly fruits and arthropods; also nectar. Eleven stomachs contained only vegetable matter; contents of other stomachs were mistletoe berries (Loranthaceae), termites (Isoptera), spiders (Araneae), and caterpillars. In Trinidad study, fed on 21 species of fruit, especiallyDidymopanax morototoni in Araliaceae (23% of all observations of fruit-eating),Cecropia (18%) andMiconia (12%). Everywhere found in pairs, and in some areas gathers in small loosely associated groups when not breeding, and may roost in larger groups; also briefly joins mixed-species flocks, and readily visits fruiting trees with other species. Noisy and conspicuous. Foraging behaviour versatile, as it peers head down along branches, scans foliage, sallies clumsily to air, takes variety nectar from flowers. In Trinidad, 82% of observed foraging attempts were at 8 m or higher, only 6% below 3 m; 53% of records were of fruit-eating, 37% of insect-seeking, and 10% at flowers. Took small fruits and berries while perched, but clung to larger fruits and pecked out pieces of fruit. Searches for insects by moving quickly through foliage and reaching up to undersurfaces of leaves, stretching and peering at tops of leaves, or lunging to snap prey. Also inspects undersides of branches and twigs by leaning down diagonally and fluttering or lunging to pursue escaping prey, and may sally short distances upwards to air for flying insects. In Trinidad, 56% of insects were obtained on foliage, 17% on branches and twigs, 11% on flowers and seedheads, and 16% in aerial sallies.

Breeding. Season mostly Feb-Jul in Middle America, Jan-Jul in Panama; more or less all months in N South America from Colombia E to Suriname, and in all months except Sept in Trinidad. Usually monogamous; one reported case of bigamy in Costa Rica. Nest built by both sexes, a thick deep cup of rootlets, moss, grass, ferns, leaves and other fine material, mostly 3-20 m up, but occasionally on or almost on ground or as high as 30 m above it, usually well hidden in leafy branch fork, base of palm frond, crevice in building, even in nest of other species such as thornbird (Phacellodomus); often pilfers material from unfinished or even occupied nests of other species, including other tanagers, euphonias and tyrant-flycatchers (Tyrannidae). Clutch 1-3 eggs, usually 2, whitish to greyish-green with brown or darker markings; incubation by female, period 12-14 days; chicks fed by both sexes, nestling period 17-18 days; in Costa Rica, one male and two females attended a nest with 4 eggs, both females incubated (dominant female for 77% of time), and all three adults fed young.

Movements. Resident. Some local movements in response to changing fruit abundance may occur.

Status and Conservation. Not globally threatened. Widespread and abundant. Perhaps the most familiar of all tanagers to rural and urban inhabitants alike, and one of the most familiar birds in settled areas in N Neotropics.In Colombia, expanded its range upwards in early 1980s, onto Sabana de Bogotá at 2600 m, where now numerous. Found in hundreds of parks and protected sites throughout its large range. Utilizes a variety of second-growth and disturbed habitats, both urban and rural, which has permitted it to expand its range and increase its numbers almost throughout its range. Causes some damage locally to papaya (Carica papaya) and other fruits in gardens.

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