Olive-crowned Yellowthroat

Overview

The olive-crowned yellowthroat (Geothlypis semiflava) is a species of bird in the family Parulidae, the New World warblers. It is found in Colombia, Costa Rica, Ecuador, Honduras, Nicaragua, and Panama, where it is generally considered to be of Least Concern on the IUCN Red List.

Identification

• Length ranges from 11.1 to 13.5 cm with a weight of 15.5 to 17.5 g; the species is sexually dimorphic.
• Adult males of the nominate subspecies feature a wide black mask extending from the forehead to the side of the neck, olive-green upperparts, and yellow underparts with an olive wash on the flanks.
• Adult females lack the black facial mask, possessing a mostly olive-green head with a thin yellowish supercilium and similar underparts to males.
• All subspecies have a dark iris, a black bill with pale horn tomia and gonys, and pinkish horn or dull orange legs and feet.

Habitat

The species inhabits a variety of landscapes, including marshes, damp pastures with tall grass and shrubs, and thickets of bamboo, typically near water sources such as ponds or moving watercourses. Its elevation range spans from sea level to 1,500 m overall, though it reaches 1,800 m in Colombia and mostly remains below 1,200 m in Ecuador.

Diet

While the diet has not been formally studied, it is assumed to consist mostly of insects and other invertebrates. The bird typically forages singly or in pairs, capturing prey by gleaning from low, dense vegetation.

Did you know?

The nominate subspecies produces a rich and musical series of phrases that usually ends in a jumble, transcribed as "sew-sew-swe’swe’sweseewuu-seewuu...". In Costa Rica, the species sings sweet, wren-like phrases distinct from the nominate's style.