The Volcano Junco, Junco vulcani, is an American sparrow

American sparrow

American sparrows are a group of mainly New World passerine birds, forming part of the family Emberizidae. American sparrows are seed-eating birds with conical bills, brown or gray in color, and many species have distinctive head patterns....

 endemic to the high mountains of Costa Rica

Costa Rica

Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....

 and western Panama

Panama

Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...

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This junco

Junco

A Junco , genus Junco, is a small North American bird. Junco systematics are still confusing after decades of research, with various authors accepting between three and twelve species...

 breeds above the timberline, typically at altitudes above 3000m, but there is an isolated population at 2100 m on the Caribbean slope of Costa Rica, and forest clearance on Cerro de la Muerte

Cerro de la Muerte

Cerro de la Muerte is the highest point in the Costa Rican section of the Inter-American Highway. Its name means "Mountain of Death", since in the past crossing the mountains from the Valle Central meant a three or four day journey, on foot or on horseback, and many ill-prepared travelers...

 has allowed this species to descend to 2600 m. The habitat is open grassy or brushy areas with some stunted scrubs. The nest is a neat lined cup constructed on the ground under a log, bush or rock, or in a cavity on a vegetated bank. The female lays two brown-spotted pale blue eggs.

The Volcano Junco is on average 16 cm long and weighs 28 g. The adult has brown upperparts with dark streaking especially on the back. The wings and tail feathers are dark fringed. The underparts are grey. The sides of the head are grey with a black mask through the eye, a yellow iris, and a pink bill and legs. Young birds are brighter brown above with blacker streaking, and have buff-grey underparts.

Volcano Junco calls include a thin tseee or a clearer wheew. The song is a mixture of sqeaks and buzzes; k’chew chu k’wee chip chip chueee.

The Volcano Junco feeds on the ground on seeds, fallen berries, insect

Insect

Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

s and spider

Spider

Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...

s. It runs and hops, but flies only short distances.