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Endémique

• Scientific Name: Sporophila ardesiaca
• Spanish Name: Semillero de Dubois
• Famille : Thraupidae
• Known Nicknames: Dubois's Seedeater
• Average Length: 10–11 cm / 3.9–4.3 in
• Average Weight: 10–12 g / 0.35–0.42 oz
• Envergure : N/A
• Key Feature: Male has slate-gray upperparts, black face and throat, white belly and wing speculum; female is olive-brown above and buff below
• Primary Diet: Primarily Granivore (seeds, especially grasses)
• Range: Southeastern Brazil (Minas Gerais, Espírito Santo, Rio de Janeiro, São Paulo)
• Habitat: Open grassy areas, pastures, savannas, and scrubby fields near water
• Social Structure: Small flocks, often mixed with other seedeaters
• Nesting/Breeding: Small cup-shaped nest in low bushes or grass clumps
• Statut de conservation : Préoccupation mineure (LC)
• Évolution démographique : Stable

Dubois's Seedeater (*Sporophila ardesiaca*) is a small, striking finch native to the grasslands and savannas of central South America, primarily in Brazil. Its most unique characteristic is the male's distinctively deep, slate-gray plumage, which contrasts sharply with a pure white throat and lower belly, giving it a "hooded" appearance—a subtle but definitive difference from its close relative, the similar-looking Double-collared Seedeater. Females are a more cryptic, warm brown, allowing them to blend into their grassy habitats. A special feature of this species is its highly specialized, conical bill, perfectly adapted for cracking open grass seeds, and its exuberant, melodious song, which is often delivered from an exposed perch during the breeding season. This seedeater is a master of its environment, playing a vital role in seed dispersal within its threatened cerrado ecosystem.

Faits amusants

Dubois’s Seedeater is such a dedicated vocal mimic that males have been recorded perfectly imitating the songs of up to 15 other bird species, including the calls of local thrushes and tanagers, often to confuse rivals or attract females. They possess a uniquely specialized lower mandible with a sharp, curved edge that acts like a tiny seed-cracker, allowing them to pry open the tough outer husks of grass seeds that other finches cannot handle. During courtship, the male performs a quirky “bouncing flight” where he rises several feet into the air while rapidly fluttering his wings and singing, then drops back to his perch in a precise, vertical plummet. Despite their small size, these birds are fiercely territorial and will aggressively chase away much larger species, such as doves or even small hawks, if they venture near a favored feeding patch.

Habitats et répartition

The Dubois's Seedeater is found in a relatively restricted geographical range within eastern Brazil, primarily in the states of Goiás, Minas Gerais, and possibly São Paulo. Its habitat consists of dry to semi-humid grasslands, often associated with the Cerrado biome, including campos rupestres (rocky fields) and open savanna with scattered shrubs. It favors areas with tall grasses and herbaceous plants, typically avoiding dense forests or heavily modified agricultural lands, though it may persist in disturbed patches with suitable grass cover.

Comportements & Reproduction

The Dubois's Seedeater is typically observed in small, loose flocks or pairs, especially during the breeding season which corresponds to the austral summer. Males establish and defend song perches to attract females, performing short, fluttering display flights while singing. Courtship involves the male offering nesting material or food to the female, who then constructs a small, cup-shaped nest in low shrubs or grass tussocks. This species is likely monogamous for a given breeding attempt, with both parents participating in feeding the altricial young. A notable aspect of its reproductive strategy is that it appears to be a habitat specialist, often breeding in seasonally flooded grasslands or marsh edges, which may synchronize nesting with peak insect availability for chick provisioning. Females typically lay two to three eggs, and the incubation period lasts approximately 12 to 14 days, with fledging occurring around two weeks after hatching.

Alimentation

Dubois's Seedeater is, as its name suggests, a granivorous bird that primarily subsists on a diet of grass seeds, which it forages directly from the stems and heads of grasses in its open, grassy habitats. An interesting aspect of its feeding behavior is its strong preference for seeds that are still in a soft, milky, or semi-ripe stage, rather than fully dried and hard grains. This specialized preference often leads it to feed in specific microhabitats where grasses are at this particular stage of development. Additionally, while seeds form the bulk of its intake, it will occasionally supplement its diet with small insects, particularly during the breeding season, to provide extra protein for growing chicks.

Couleurs

The male Dubois's Seedeater is predominantly dark slate-gray to blackish, with a white wing speculum (shoulder patch) and a small but distinct white spot at the base of the lower mandible. Females are a plain, unstreaked olive-brown above and paler below, lacking any bold markings. This species shows no specific camouflage adaptations beyond the female’s cryptic dull coloration, which blends into dry grassland and scrub habitats.

Distribution Map

Places linked to this species. A sighting is never guaranteed.

Détails de l'attraction

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