Brown-headed Cowbird

The brown-headed cowbird (Molothrus ater) is a small, obligate brood parasitic icterid native to temperate and subtropical North America. It is a permanent resident in the southern parts of its range; northern birds migrate to the southern United States and Mexico in winter, returning to their summer habitat around March or April. The brown-headed cowbird is typical for an icterid in general shape, but is distinguished by its finch-like head and beak and smaller size. The adult male is iridescent black in color with a brown head. The adult female is slightly smaller and is dull grey with a pale throat and very fine streaking on the underparts. Their total length is 16–22 cm (6.3–8.7 in) and the average wingspan is 36 cm (14 in).[10] Body mass can range from 30–60 g (1.1–2.1 oz), with females averaging 38.8 g (1.37 oz) against the males' average of 49 g (1.7 oz).