Rock Wren

Overview

The rock wren (Salpinctes obsoletus) is a small songbird of the wren family native to the rocky areas of western North America. It is a largely terrestrial forager that rarely flies, preferring open rocky habitats such as canyons and cliffs.

Identification

• Size: Between 12.5–15 cm in length with a wingspan of 22–24 cm.
• Plumage: Grey-brown upperparts with small black and white spots, pale grey underparts, and a light brown rump.
• Markings: Features a light grey line extending through the eye, a speckled light grey throat, and zebra-striped undertail coverts.
• Song: Males possess large repertoires of 69–119 syllables, singing short trills with a distinctive pattern that repeats each syllable three to four times within a burst.

Habitat

Rock wrens are permanent residents in the southern parts of their range, including areas in western North America, Central America, and inland Mexico, while also breeding in regions like British Columbia and the US Mountain West. They inhabit rocky open areas such as exposed rock, canyons, and cliffs, though they can also utilise large eroded sandbanks. They are rare in urban areas but tolerate a wide altitude range, breeding from 60 m to 3,600 m above sea level.

Diet

Their diet consists primarily of insects, such as leafhoppers, ants, and weevils, with occasional consumption of spiders and seeds. They forage during the day on open ground, rummaging the surface of rocks and soil and probing crevices. In autumn and winter, their diet shifts towards grain.

Did you know?

Rock wrens build 'pavements' using flat stones around their nests to keep nestlings dry and help them maintain their body temperature. These pavements can consist of an average of 230 stones, each weighing about 20% of the bird's own body mass.