Rusty-crowned Ground Sparrow

Overview

The rusty-crowned ground sparrow is a species of bird in the family Passerellidae that is endemic to Mexico. It is classified as Least Concern on the IUCN Red List, although its estimated population of at least 50,000 mature individuals is believed to be decreasing.

Identification

• 15 to 18 cm long and weighing 35 to 41 g, with a dusky black forecrown and rufous crown that extends behind and under the ear coverts.
• Upperparts, wings, and tail are brown, while underparts are mostly white with a central black breast spot, brown flanks, and rufescent undertail coverts.
• Features white lores, a broken white eye-ring, a black or blackish bill, and brownish or pinkish legs.
• Song consists of a very high, simple, calm, unstructured 'tjitit-tjitit-tutututut', accompanied by high, thin lisps and sharp chips.

Habitat

Inhabits western Mexico in the Sierra Madre Occidental, Sierra Madre del Sur, and Cordillera Neovolcanica. It occupies arid to semi-humid landscapes in upper tropical and subtropical zones, including thorn forest, dry brushy woodlands, arid scrublands, and secondary forest. Elevational range is estimated between sea level and 1,500 to 2,000 m.

Diet

Diet is assumed to include seeds and arthropods, though it has not been formally studied. It forages on the ground and in low vegetation by hopping, usually seen singly or in pairs.

Did you know?

Observations of 11 nests found in 1962 revealed that nine were parasitised by bronzed cowbirds and one by a brown-headed cowbird, indicating high levels of brood parasitism.