Platyspiza crassirostris

The vegetarian finch (Platyspiza crassirostris) is a species of bird in the Darwin's finch group of the tanager family Thraupidae. It is monotypic within the genus Platyspiza. It is endemic to the Galápagos Islands. Its natural habitats are subtropical or tropical dry forests and subtropical or tropical moist montane forests. The vegetarian finch is one of Darwin's finches, a group of closely related birds which evolved on the Galápagos Islands. The group is related to the Tiaris grassquits, which are found in South America and the Caribbean. An ancestral relative of those grassquits arrived on the Galápagos Islands some 2–3 million years ago, and the vegetarian finch is an early evolutionary radiation from that ancestor. When Darwin first collected the species in 1835, he assumed it was a finch. John Gould, who formally described the vegetarian finch in 1837, agreed and assigned it to the genus Fringilla. By 1841, Gould had changed his mind, and moved the species to the genus Camarhynchus, lumping it with the ground and cactus finches. Robert Ridgway separated it from the other species in 1896, assigning it to a new genus Platyspiza. DNA research has now shown that all Darwin's 'finches' are actually tanagers. The vegetarian finch is the sole member of the genus Platyspiza, which some taxonomists still subsume into the genus Camarhynchus. The genus name Platyspiza comes from the Greek platus, meaning 'broad' and spiza, meaning 'finch'. The specific name crassirostris comes from the Latin crassus, meaning 'heavy' or 'thick' and rostris, meaning '-billed' (rostrum = bill). The 'vegetarian' of its common name refers to its primary diet. The vegetarian finch is one of the largest Galápagos finches, measuring 16 cm (6.3 in) in length and ranging from 29 to 40 g (1.0 to 1.4 oz) in mass. Its upright stance is described as 'parrot-like'. Its beak is broad and stout, with a strongly curved culmen. The male's upperparts are olive-colored while his underparts are whitish, with smudgy streaking on the lower breast and flanks; some birds show rufous on the underparts. His lower flanks and undertail coverts are buffy. He has a black hood, throat, breast and upper flanks. His iris is dark, and his bill is black in the breeding season and horn-colored during the rest of the year. The female is principally brown above and off-white below, with a buffy rump and flanks. She is streaked with brown on the face, crown, upperparts, throat, breast and flanks, and shows two indistinct buffy wingbars on her brown wings. Her beak is two-toned; the upper mandible ranges in color from dusky brown to black, while the lower mandible is dull orange or dull pink. The immature male is intermediate between the adult male and the adult female. While he shows blackish on his face and throat, he is more streaked below than is the adult male. The song of the vegetarian finch is nasal and drawn out, with each note lasting about two seconds. Transcribed as ph'wheeeuuuuu-íííúúú, it is accented towards the end. The bird's primary call is high-pitched and squealing, said to resemble the sound of a radio tuner. It also gives a whiny pheep. Endemic to the Galápagos, the vegetarian finch is found on eight islands: San Cristóbal, Santa Cruz, Floreana, Isabela, Marchena, Santiago, Pinta and Fernandina. Although it was previously found on Pinzón and Santa Fé, the species is now extinct on both islands. It is found from 0 to 500 m (0 to 1,640 ft) above sea level. Although it is most common in montane evergreen forest, particularly the transition zone, its range also extends up into the humid zone and down into the arid zone. Little is known about the breeding ecology of this species. It breeds primarily in the wet season, building a grassy domed nest with a side entrance. Courtship feeding is known to occur throughout courtship and incubation, with some pairs passing food items back and forth several times.