the bronzed cowbird (once known as the red-eyed cowbird), (molothrus aeneus), is a small icterid .
it breeds from the southern u .
s .
states of california , arizona , new mexico , texas , and louisiana south through central america to panama .
they tend to be found in farmland , brush , and feedlots .
outside the breeding season , they are found in very open habitats , and roost in thick woods .
they forage in open areas , often nearby cattle in pastures .
their diet mostly consists of seeds and insects , along with snails during breeding season for a calcium source .
there are three subspecies and an isolated population on the caribbean coast of colombia that is sometimes treated as a separate species , the bronze-brown cowbird (m .
armenti)the male bronzed cowbird is 20 cm (7.9 in) long and weighs 68 g (2.4 oz), with green-bronze glossed black plumage .
their eyes are red in breeding season and brown otherwise .
the female is 18.5 cm (7.3 in) long and weighs 56 g (2.0 oz) .
she is a dull black with a brown underbelly , and has brown eyes .
young birds have coloring similar to the females , with the exception of grey feather fringes .
like all cowbirds , this bird is an obligate brood parasite; it lays its eggs in the nests of other birds .
the young cowbird is fed by the host parents at the expense of their own young .
hosts include prevost's ground-sparrow and white-naped brush finch .
they develop rapidly , leaving the nest after 1012 days .
