Rufous-rumped Antwren

The Rufous-rumped Antwren, a diminutive and slender bird with a notable long tail, bears a resemblance to greenlets or New World warblers. This species, with a length of 10 to 12 cm and a weight of approximately 7 to 9.5 grams, exhibits sexual dimorphism in its plumage.

Identification Tips

Males of the Rufous-rumped Antwren are characterized by blackish lores and a line through the eye on a pale gray face, with a black crown and nape. Their upper back is olive, transitioning to a bright rufous or orange-brown lower back and rump, and olive uppertail coverts. The tail is dusky with olive edges, and the wings are slate gray with pale yellow tips forming two bars. The throat and breast are pale gray, while the belly and undertail coverts are pale yellow-green. Females, on the other hand, have a brownish olive crown and grayish olive head sides. Both sexes have brown or dark brown irises, a black maxilla, a mandible in shades of gray with a black tip, and bluish gray or gray legs and feet.

Habitat

This bird favors the interior and edges of humid foothill and montane forests.

Distribution

The Rufous-rumped Antwren is found in a highly disjunct range across several countries in Central and South America, including Costa Rica, Panama, Colombia, Ecuador, Peru, Venezuela, Guyana, Suriname, and French Guiana.

Behaviour

A year-round resident, the Rufous-rumped Antwren typically forages in pairs and often joins mixed-species feeding flocks, predominantly in the forest canopy.

Song & calls

The song of the Rufous-rumped Antwren is a high-pitched, rapidly accelerating trill, while its calls consist of high "tsi" and "ti" notes.

Breeding

The breeding season in Costa Rica is from February through May, but further details on its breeding biology are not well documented.

Similar Species

There are no similar species mentioned in the provided content.

Diet and Feeding

The Rufous-rumped Antwren consumes arthropods, gleaning prey acrobatically from leaves and sticks in the canopy.

Conservation status

The IUCN has classified the Rufous-rumped Antwren as Least Concern, with a large range and an estimated population of at least 50,000 mature individuals. However, the population is believed to be decreasing, and the species is vulnerable to habitat loss or degradation due to human activities such as forest clearing for agriculture. It is considered rare in Costa Rica and uncommon in Colombia, Ecuador, and Peru.