- Order: Passeriformes
- Family: Thraupidae
- Polytypic 3 Subspecies
As its name suggests, the plumage of the Blue-and-black Tanager primarily is dark blue and black. Overall, this species is an average-sized member of the genus Tangara, but its bill is unusually short compared to others in this genus (Hilty 2003).
Southern Blue-and-black Tanagers (atrocaerulea) can be confused with sympatric populations of the Golden-naped Tanager (Tangara ruficervix inca), but the Blue-and-black Tanager has a blacker back, with black spotting below, and lacks the cinnamon colored underparts of the Golden-naped Tanager (Ridgely and Tudor 1989, 2009). Throughout its range the Blue-and-black Tanager also may be confused with the Masked Flowerpiercer (Diglossa cyanea) because of its pure blue coloration and black coloration around the face (Ridgely and Tudor 1989, 2009). The Blue-and-black Tanager, however, lacks the red eye of the Masked Flowerpiercer, has more black on its wings and tail, and has a shorter and thicker bill that lacks a hook.
The call notes of the Blue-and-black Tanager include a very thin, high-pitched, but emphatic tsit, sometimes given in a rapid ticking series, especially as individuals take flight; they also give a slightly lower swit, sometimes a repeated swit! swit! swit!, or a harder SWIT-it (Isler and Isler 1987). Song is rarely heard, but described as a short (2-3 s) series of upward-inflecting, rhythmical high-pitched "wheedly" notes that starts slowly and progresses rapidly into an active zieeu-zie-zie-zizizizee trill that is given every 15 seconds (Fjeldsa and Krabbe 1990, Hilty and Brown 1986).
Detailed Description (appearance)
Overall coloration is blue and black, as the name suggests. The following description refers to the nominate race, T. v. vassorii. Characteristics of the other subspecies are outlined in Geographic Variation.
Adult male: Overall shining dark cobalt blue with a small black mask. The underparts are dark blue. The wing and tail feathers are black with dark blue narrow edges. Shoulders and wing bar are dark blue with the greater wing coverts a dark blue with black tips. The bill is unusually short and thick compared to other Tangara. (Hilty and Brown 1986, Ridgley and Tudor 1989).
Adult female: The adult female Blue-and-black Tanager is similar to the male but is slightly duller (Isler and Isler 1987).
Subadult: Overall gray but the wing, tail, and lores are black, similar to adults. T. v. vassorii is smoky gray (Isler and Isler 1987).
Iris: Brown (Restall et al. 2007)
Bill: Black (Restall et al. 2007)
Tarsus: Vinaceous Gray (Restall et al. 2007)
Total length: 13 cm (Isler and Isler 1987)
|Sex||n||Mean ± SD (range)||First Quartile||Third Quartile|
|Female||4||18.4 ± 0.6 (17.6–18.8)||18.9||18.7|
|Male||22||17.5 ± 0.8 (16.1-18.9)||16.9||17.8|
|Undetermined||7||17.0 ± 1.1 (15.6-18.6)||16.2||17.7|
|Combined||3||17.5 ± 0.9 (15.6-18.9)||17.6||18.0|
Mass, both sexes, compiled by Isler and Isler (1987) from specimens at the LSUMZ: mean 18.0 g (range 15.0-21.0 g, n = 63).
In general, most tanagers only molt once a year (Isler and Isler 1987), and this prebasic molt likely occurs after the breeding season (Isler and Isler 1987, Ryder and Wolfe 2009). However, many species have been found to breed in subadult plumage (Isler and Isler 1987). In many species of Tangara, the preformative molt is partial (Ryder and Wolfe 2009). Although a subadult plumage is described for Tangara vassorii (Isler and Isler 1987), more specific information its timing is not available. Specimen data of birds in the Field Museum of Natural History collection indicate molt during the months of March (3 specimens), October (2 specimens), November (1 specimen), and December (1 specimen).
Three subspecies usually are recognized:
T. v. vassorii- This subspecies has a rich cobalt blue color with its lores, wing, and tail feathers black. The subadult overall is gray, tinged with blue, with the lores, wing, and tail feathers a duller black. There is no nape patch, and the greater wing coverts are black tipped with blue. Occurs from Venezuela south to northern Peru (Piura and northern Cajamarca).
T. v. atrocaerulea- The blue of this subspecies is lighter than that of T.v. vassorii; the coloration is described as "Faxflower Blue" by Isler and Isler (1987) rather than the deep cobalt blue of the nominate subspecies. The nape has an opalescent yellowish (rarely white) patch. It also has some black spotting among the underparts and head. The juvenile is grayish with faint streaks among its breast (Isler and Isler 1987, Fjeldså and Krabbe 1990). Occurs from in the Andes of northern Peru, from Amazonas (south of the Río Marañón) south to La Libertad.
T. v. branickii- This subspecies resembles the nominate race overall; however, the top and sides of the head are tinged with gray and have a dull bluish green. This subspecies also is paler on the hind-crown (Isler and Isler 1987, Fjeldså and Krabbe 1990). Occurs from central Peru (Huánuco) south to Bolivia.
The Blue-and-black Tanager is classified in the genus Tangara, the largest genus of Neotropical birds. Tangara is divided into 13 species groups based on vocalizations, diet, geographic distributions, behavior, and appearance (Isler and Isler 1987). Isler and Isler (1987) placed T. vassorii in their species group 11, along with Spangle-cheeked Tanager (T. dowii), Green-naped Tanager (T. fucosa), and Beryl-spangled Tanager (T. nigroviridis). Genetic evidence from mtDNA confirms the monophyly of this group (Burns and Naoki 2004, Sedano and Burns 2010). With strong statistical support, these molecular phylogenies show that T. vassorii is the sister taxon to the clade containing the other three species in the group.
Bernabe, Annabelle, and Kevin J. Burns. 2011. Blue-and-black Tanager (Tangara vassorii), Neotropical Birds Online (T. S. Schulenberg, Editor). Ithaca: Cornell Lab of Ornithology; retrieved from Neotropical Birds Online: http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=%0A%09%09%09%09609516