Brown-headed cowbird

Description:

Some definite mating displays going on with these guys this morning. I tried to take a little vid but it's too shaky to put up. Predominantly black plumage on the body with a brown head (male). Female birds are slightly smaller and are dull grey with a pale throat and fine streaking on the underparts.

Notes:

From wikipedia and references therein: The brown-headed cowbird is an obligate brood parasite: it lays its eggs in the nests of other small passerines (perching birds), particularly those that build cup-like nests. The brown-headed cowbird eggs have been documented in nests of at least 220 host species, including hummingbirds and raptors. Unlike the common cuckoo, the brown-headed cowbird is not divided into gentes whose eggs imitate those of a particular host. Some host species, such as the house finch, feed their young a vegetarian diet. This is unsuitable for young brown-headed cowbirds, meaning almost none survive to fledge