Bare-faced Ibis

The bare-faced ibis is best recognized by its bare, reddish facial skin, a trait no feathered ibis in its range shares. Its plumage is dark brown to blackish overall, giving it a somber, uniform appearance at a distance.

The bird measures between 45 and 50 centimeters in total length and weighs around 0.559 kilograms. Its long, decurved bill is pinkish to reddish brown, paired with pink legs that contrast against the darker body.

Sexual differences are subtle but present: males carry a proportionally larger bill than females relative to body size, though this difference is not extreme and sexual selection pressures appear modest compared to other ibis species.

The bare-faced ibis occupies a broad range across South America, found in Argentina, Bolivia, Brazil, Colombia, Ecuador, Guyana, Paraguay, Suriname, Uruguay, and Venezuela, spanning an estimated range of 6,590,000 square kilometers.

It favors open, wet habitats: wet meadows, savannas, marshes, and rice fields. The species is typically found near sea level, though it has been recorded at higher elevations in Venezuela and Colombia.

Monthly observation records show birds present throughout the year, with some months showing higher observation numbers than others, though these counts reflect presence rather than actual population size or abundance.

The bare-faced ibis is a highly social bird, usually seen in large flocks composed of its own species or mixed with other ibis, and occasionally alongside domestic animals. Individuals nest in close proximity to one another, with neighboring nests sometimes as little as 100 meters apart.

Despite this crowding, the species shows little territorial aggression toward other ibis. Conflict is generally limited to occasional food robbery from another ibis or animal rather than sustained hostility. Nesting behavior is notably less aggressive compared with other ibis species, and the birds will even share nesting sites with other species entirely.

The species is partially migratory and terrestrial in its general lifestyle, moving between foraging grounds as conditions change across its wide range.

The bare-faced ibis forages by probing soil and the edges of standing water, acting as an aquatic predator that hunts small invertebrates hidden in mud and shallow wetlands. Its long decurved bill is well suited to this probing style of feeding.

Its diet consists mainly of insects, worms, clams, and other small invertebrates, all of which it locates by working through soft ground and water margins rather than by chasing more mobile prey.

Bare-faced ibises breed in small colonies alongside their own species, with the breeding season running from August to December. Courtship and nest-building lead to platform nests built in trees or shrubs, often close to neighboring nests.

A clutch typically contains 1 to 8 eggs, pale green to blue in color. Incubation lasts 21 to 23 days and is shared by both the male and female, reflecting the relatively cooperative, low-aggression nesting style typical of the species.

1. The bare-faced ibis is the only species in its genus, Phimosus, making it taxonomically unique within the ibis family.
2. It is sometimes called the whispering ibis, an alternate common name alongside bare-faced ibis.
3. The species has been recorded living alongside other birds such as the smooth-billed ani, Chaco chachalaca, and red-and-green macaw in shared habitats.