Conopophagidae – Gnateaters

The gnateaters (sometimes known as antpipits) are a bird family, Conopophagidae, consisting of twelve small passerine species in two genera, which occur in South and Central America. The family was formerly restricted to the gnateater genus Conopophaga, however, analysis of mtDNA cytochrome b and NADH dehydrogenase subunit 2 sequences (Rice 2005a,b) indicates that the ‘antpittas’ of the genus Pittasoma also belong in this family. The association between this genus and Conopophaga is also supported by traits in their natural history, morphology, and vocalisations. The members of this family are very closely related to the antbirds and less closely to the antpittas and tapaculos. Due to their remote and dim habitat, gnateaters are a little-studied and poorly known family of birds.

They are round, short-tailed, and long-legged birds, about 12–19 cm in length, with Pittasoma being larger than Conopophaga. They are quite upright when standing. All species are sexually dimorphic, although the extent of this varies greatly. Most Conopophaga species have a white tuft behind the eye.

Black-cheeked Gnateater Conopophaga melanops – ©Dubi Shapiro

Gnateaters are birds of the forest understory, bamboo stands, and the forest floor. The members of the genus Conopophaga are found in the Amazon and Orinoco basins, east and central Andean slopes, Atlantic Forest, and nearby regions, while the members of the genus Pittasoma are found in the Chocó, and Panama and Costa Rica. Some species live in impenetrable thickets; others live in more open forest. Most are entirely restricted to humid habitats, but several species extend into drier regions in eastern Brazil. While the members of the genus Conopophaga always are found near the forest floor, seldom rising more than 1.5 m above the ground, they also seldom travel or spend much time on the ground (though they do feed there). The members of the genus Pittasoma are more commonly seen hopping around on the ground.

Rufous-crowned Antpitta Pittasoma rufopileatum – ©Dubi Shapiro

Most gnateaters make cup-shaped nests in the rainy season, often with a cluttered appearance, using materials like leaves, rootlets, and twigs. They are typically situated low to the ground, near branches or stems in the undergrowth, and lined with fine rootlets. One study mentioned a nest located about 65 cm above the ground on a steep slope at the base of a large tree root. Another example involves a nest of the Hooded Gnateater built on an epiphytic fern and lined with dark green leaves, with an exterior of dried leaves and thin dry sticks. They are thought tp be monogamous and both sexes participate in nest construction and parental care. The incubation period is at least 12 days, and the chicks stay in the nest for about 18 days. 

Black-crowned Antpitta Pittasoma michleri – ©Dubi Shapiro

Gnateaters tend to have loud, usually unmusical voices that may be heard in echo duets. However, some are known for their diverse vocalizations, including songs, calls, and subsong, often accompanied by wing sounds. Their vocalizations vary, with some species exhibiting distinct calls for alarm and nestling vocalizations differing from adults. For example, there are recordings of Rufous Gnateater Conopophaga lineata songs that are both short and longer, with variations in pace and note number. Furthermore, some subspecies show significant vocal differences, potentially indicating separate taxa. Nestlings have their own unique vocalizations, which can differ from those of adults, particularly in frequency and modulation.

Slaty Gnateater Conopophaga ardesiaca – ©Dubi Shapiro

Gnateaters are insectivorous as the group name implies. The members of the genus Conopophaga feed mostly using two methods; one is to perch above the forest floor until prey is spotted, then lunge down to the ground to snatch it; having landed on the ground to snatch a prey item it will not remain on the forest floor for more than a couple of seconds. The second method used is to glean insects directly from the foliage, trunks, and branches of low vegetation. Typical prey items include spiders, caterpillars, insect larvae, grasshoppers and beetles; individuals of some species have also been observed eating fruit and in one case a frog.

Very little information is available on the diet of the two Pittasoma, but they are also presumed to be insectivorous, and have been recorded following army ants swarms – more to take advantage of the insects displaced by the ants, than the ants themselves.