Rock earthcreeper


The rock earthcreeper is a species of bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Argentina and Bolivia, and as a vagrant in Chile.

Taxonomy and systematics

For a time the straight-billed earthcreeper was placed in genus Upucerthia but since the early 2000s has been in its present genus.
The straight-billed earthcreeper is monotypic.

Description

The rock earthcreeper is long and weighs. It is a medium-sized earthcreeper whose bill is long and slightly decurved. The sexes are alike. Adults have a buff supercilium, a dark brownish stripe behind the eye, and buff cheeks. Their crown, back, and rump are rich brown and their uppertail coverts dark rufous-brown. Their tail is dark rufous and their wings slightly more rufescent than their back. Their throat is buffy whitish, their breast and belly darker with a tawny tinge and darker streaks on their sides and flanks, and their undertail coverts tawny. Their iris is brown, their bill blackish with a pale gray base to the mandible, and their legs and feet dark brown or gray-brown. Juveniles have pale feather edges on their back and a scaly pattern on their underparts.

Distribution and habitat

The rock earthcreeper is found in the eastern foothills of the Andes Mountains, from La Paz Department in western Bolivia south into northern Argentina as far as Catamarca Province, and extreme eastern Antofagasta Region of Chile.
The rock earthcreeper inhabits arid scrublands and puna grasslands with bunchgrass and scattered bushes. It favors rocky hillsides, rocky outcrops, and ravines. In elevation it mostly ranges between and occurs locally as high as.

Behavior

Movement

The rock earthcreeper is a year-round resident throughout its range, except perhaps in Chile.

Feeding

The rock earthcreeper forages on the ground for its arthropod diet, usually singly but also in pairs. It gleans and extracts its prey while hopping among the rocks, bunchgrass, and bushes of its habitat. It is often wary and difficult to approach, flying off for considerable distances when disturbed.

Breeding

The rock earthcreeper is thought to be monomgamous. It apparently breeds in the austral summer. It excavates a tunnel in an earthen bank or occupies a rock crevice, and lines the nest chamber with soft material such as grass, hair, and feathers. The clutch size is two eggs. The incubation period, time to fledging, and details of parental care are not known.

Vocalization

The rock earthcreeper sings from a perch on a bush or boulder, a series of loud, shrill notes "vee-vee-vee-vee-vi-veet", sometimes ending with a splutter. It makes an alarm call, "a high-pitched, rodent-like, squeaky, whistled 'zuwééét' ".

Status

The IUCN has assessed the straight-billed earthcreeper as being of Least Concern. It has a somewhat limited range and its population size is not known and is believed to be decreasing. No immediate threats have been identified. It is considered uncommon to fairly common, and is thought "reasonably secure, with overgrazing the only human disturbance".