Great-billed Seed-Finch

Sporophila maximiliani

Medium-sized, finch-like bird with long tail and strong, sturdy bill. Males have uniformly black plumage and impressively large contrasting white bill, while the females are brownish with dusky, blackish bill. Size and shape similar to Chestnut-bellied Seed-finch, but note larger size, colder brown coloration, and heftier bill. Usually alone or in pairs, rarely in isolated flocks. Uncontrolled trapping for the cage bird trade has severely threatened this species.

Identification

The great-billed seed finch is sexually dimorphic.  They have an extremely large and thick bill, that is chalky white in males and black in females.  The beak volume is about 840mm³. The males are black with white or white and black under wing-coverts.  The females have a warm brown back and a buffy brown belly with white under wing-coverts.  The females are very similar to other adult females of the Sporophila genus. Both the male and female great-billed seed finch are very similar in appearance to the male and female large-billed seed finch.  It is a medium-sized finch at around 14.5-16.5 cm in length.  The juvenile is similar in appearance to the female.  Sexual dimorphism presents itself in males when they begin to sing. The male juvenile eventually moults its black feathers, having a patchy appearance for several months until it is fully black.<p>Due to their similarity with other species, sexual dimorphism, and juvenile appearance, great-billed seed finches can be very difficult to identify morphologically.<p>The eggs of the great-billed seed finch are grayish white with black blotches and light brown spots.

Taxonomy

The great-billed seed finch was called Fringilla crassirostris when a female was collected on the eastern coast of Brazil in 1815 by Prince Maximilian of Wied-Neuwied.  Twenty years after his description was published, the seed finch was included in the newly proposed genus Oryzoborus by Jean Louis Cabanis (1851).<p>The seed finches were once categorized in the genus Oryzoborus. They are a group of six species: the chestnut-bellied seed finch (Oryzoborus angolensis), large-billed seed finch (Oryzoborus crassirostris), black-billed seed finch (Oryzoborus atrirostris), thick-billed seed finch (Oryzoborus funereus), great-billed seed finch (Oryzoborus maximiliani), and the Nicaraguan seed finch (Oryzoborus nuttingi). The females of seed finches are very similar in morphology. The taxonomy is therefore almost exclusively based on the male plumages. Categorization of the seed finches had been historically based on male plumage patterning with color groups such as gray and chestnut-colored. Further molecular and morphological analyses of the birds led to the genus Oryzoborus being subsumed into the genus Sporophila.<p>               The great-billed seed finch includes two subspecies.  The first is the S. m. maximiliani which is found mainly in Cerrado, eastern Bolivia, and in the Brazilian states of Goiás, Bahia, Minas Gerais, Espirito Santo, São Paulo, Mato Grosso, and Mato Grosso do Sul. The second is the S. m. parkesi which is found in southeastern Sucre to Elta Amacuro, northern South America, eastern Venezuela, northern Bolívar, western Guyana, and the northernmost part of Brazil.

Scientific name
Sporophila maximiliani
Authority
(Cabanis, 1851)
Order
Passeriformes
Family
Thraupidae
Genus
Sporophila

Range and habitat

The great-billed seed finch exists in two separate populations in South America. The southern population is found in the Cerrado and in the Cerrado enclaves into the transition zones in Atlantic Forest. The northern population is found in the northern Amazon rainforest.<p>The great-billed seed finch is specialized to live in humid environments and is often associated with flooded areas and marshy borders.

Migration
Resident species

Behavior

The great-billed seed finch is predominantly granivorous and feeds mainly on seeds of many Cyperaceae species.  They are usually found in pairs. Not much more is known.<p>Breeding season generally begins around November or December during spring and summer in central and southern Brazil and extends until the end of February or early March. Breeding in the great-billed seed finch is stimulated by the first torrential rains of spring. The spring rains cause the fruiting of the Cyperaceae species, which then produce mature seeds in the middle of the rainy season. During breeding season, the seed finch is especially territorial and aggressive. Their nests are cup-shaped and anywhere from one to three meters high. They lay eggs in clutch sizes of two to three eggs which are incubated by the female.

Conservation

Population trend
declining

Photos

Distribution

Other Birds

Brown-backed Scrub-Robin

Brown-backed Scrub-Robin

Cercotrichas hartlaubi

Pretty robin with a dark brown back, a boldly marked face, and an unstreaked gray chest. Found in broadleaf woodland, moist savanna, and lush cultivation. Shy bird that generally skulks in thick undergrowth except when perched up to sing. Song is a variable, musical series of whistles. Similar to Red-backed Scrub-Robin, but has two clean white wingbars, a darker brown back and crown, and a wider and bolder black band across the tail.

Gray-backed Thrush

Gray-backed Thrush

Turdus hortulorum

Brightly colored thrush of well-shaded undergrowth in a variety of habitats, from deep hilly forests to city parks and gardens. Male has clean pale gray upperparts and a bright orange belly, female and immature male replace gray with brown and have dark streaking on the throat and chest. Forages loudly in the undergrowth, usually singly or in pairs; tends not to associate with other thrush species. Often approachable.

Bearded Bellbird

Bearded Bellbird

Procnias averano

Famously loud and distinctive-looking, this large cotinga is one of the iconic species of northern South America. Male is unmistakable with mostly white body, black wings, brown head, and throat full of dangling black wattles that look like the bird threw up a plateful of worms onto itself. Female is much plainer, greenish with faint yellow streaks on the underparts. Female is extremely similar to female White Bellbird; where range overlaps with White Bellbird, Bearded typically occurs at higher elevations. Most often found by the extremely loud and far-carrying “bonk!” call given by the male.

Start Your Bird Watching Journey

Identify a bird outdoors and keep the field guide close for your next observation.