Appearance

Fawn-breasted Tanager (Pipraeidea melanonota) is an attractive tanager with an extensive range throughout much of South America. It is multiple hues of blue above and fawn colored below, with these colors separated by its broad black mask. It has short yet strong mandibles, dark brown to red eyes, and prefers to be alone or in pairs.

Fawn-breasted Tanager is most likely to be confused with Chestnut-bellied Mountain-Tanager (Dubusia castaneoventris) where their ranges overlap in Peru and Bolivia (Meyer de Schauensee 1966). However, Chestnut-bellied Mountain Tanager is larger with a blue (not black) back, and has a distinct black lateral throat stripe. Otherwise, Fawn-breasted Tanager easily can be identified. From a distance it may be confused with Rusty Flowerpiercer (Diglossa sittoides), which has the same basic coloring being blue dorsally and yellow ventrally, but which is much smaller, lacks a black mask,and has longer bill with a hook (Hilty 2003). Similarly, it can resemble Golden-rumped Euphonia (Euphonia cyanocephala), but the euphonia has a black throat, and yellow rump and vent, rather than a buff throat, blue rump, and buff vent. Finally, it may be confused with the congeneric Blue-and-yellow Tanager (Pipraeidea bonariensis). This species has the same basic color pattern, but differs in the following ways: an all blue head hood rather than just the cap and nape, the black eye mask is confined to the lores and does not include the auriculars, it is yellower below rather than buff; it has a yellow rump rather than blue; and it has a distinctly more robust bill compared to the smaller conical bill of Fawn-breasted Tanager.

The following description details the nominate subspecies, Pipraeidea melanonota melanonota; for the other subspecies see Geographic Variation. This standard sized tanager has a rather wide and short bill, similar to swallows, with a small hook, relatively short legs, short tail, and long wings (Hilty 2003, Hilty 2011). In males, the crown and nape is a medium blue, with a broad black mask that goes around the face surrounding the eyes and including the auriculars. The mantle and back is a dull blackish blue that becomes bright turquoise blue on the rump, then fades to a darker dusky blue on the uppertail coverts and tail. The upperwing coverts and tertials are blackish with dark blue edging, and the primary coverts and flight feathers are dusky blue. The throat and entire ventral side of the bird is a buff color with a cinnamon wash that is variable from darker to very pale (Hilty 2003, Hilty 2011).

The females are similar except they are considerably duller: the crown ranges from pale to dusky blue, sometimes brown tinged at the back of the head; the back is gray brownish with a dull blue sheen; and the throat and ventral surfaces are similar to the male regarding the range of cinnamon to buff, but are duller (Fjelså and Krabbe 1990, Hilty 2011). Both juvenile and immature plumages have been described. Juveniles still residing in the nest have an all over grey dorsal side and a buffy ventral side (Alquezar et al. 2010). When a little older, the dorsal side is a grayish brown with almost no pattern, and they have a pale throat and belly. Just before maturity, the look is similar to that of the females but duller still, with slightly discernable feather patterns (Hilty 2011).

Tanagers that have been studied have either a Complex Basic Strategy or Complex Alternative Strategy (Ryder and Wolfe 2009). However, 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). Many species have been found to breed in subadult plumage (Isler and Isler 1987). Reports on different aged birds may give us a generalized molting timetable, with fledglings seen in July in western Venezuela in Mérida, with immature plummages reported in August in coastal Peru in Junín (Hilty 2011). However, more specific information on molt and its timing is not available for this species.

The iris is reddish brown to red in the southeast and red or fire red in the Andes and Venezuela (Belton 1985, Hilty 2003, Ridgley and Tudor 2009, Hilty 2011). The maxilla is black or dusky, and the mandible is gray (Belton 1985, Hilty 2011). The tarsi and toes are dusky or slate gray (Belton 1985, Hilty 2011).

The total length is 13-15 cm (Isler and Isler 1987, Restall et al. 2007).

The mean mass (n = 14) is 21 g with a range of 18-25 g (Isler and Isler 1987). Similar weights of 21.8 g, 21.5 g, and 21 g have also been recorded (Contreras 1983, Smith et al. 2012). A male P. m. venezuelensis had a weight of 23.7 g (Miller 1963).

The gape width is 7.5 mm (Pizo 1997). A single female had the following measurements (mm): exposed culmen 8.6, head + bill 31.2, tarsus 17.6, wing length 79, and tail length 53 (Smith et al. 2012).