The Black-thighed Grosbeak (Pheucticus tibialis), is a large seed-eating bird in the cardinal family, which is endemic to the mountains of Costa Rica and western Panama. This species breeds from about 3200 feet (Pacific slope) or 5000 feet (Caribbean slope) up to 8500 feet and is found in canopy, woodland edge and semi-open habitats such as pasture with some trees.
The adult Black-thighed Grosbeak is 7.85 inches long, weighs 2.5 ounces, and has a massive gray bill. The male has a yellow head, rump and underparts, an olive-edged black back, and black wings, thighs and tail. There is a white patch on the flight feathers. The female is paler with more olive on the back and a smaller white wing patch. Immatures are duller and more olive-tinged, and have streaking and mottling on the body plumage.
The Black-thighed Grosbeak forages in shrubs or trees for insects, seeds and berries. The call is a sharp pink, and the song is a musical stream of warbles, whistles, trills and slurs. The nest is a thin cup constructed on a bulky twig base 1-3 m up in a small tree or amongst vines. The female lays two brown-spotted pale blue eggs between March and May.