Bay-winged cowbird which raises its own young is parasitised by its own cousin, screaming cowbird. Seeking an opportune moment, while the bay-winged is away, screaming cowbird visits its relative and quietly lays its one egg in the nest. In this way chicks of one relative are raised by another. Brood parasitic cowbirds choose host species whose eggs have an appearance similar to their own and to avoid detection they throw out one of the host s eggs for each egg they lay. Relatives of cowbirds, new world blackbirds are very common and familiar birds of Americas.
Females have buff-brown plumage speckled with darker brown and black throughout the year.
Males have a similar plumage in all times of the year except the breeding season, but when spring comes the back of their necks get bright yellow patchs and rumps and the shoulders turn white with black body. This patterning of colours gives them their local name of skunkbirds. American blackbirds have evolved unique a technique of gaping for finding their food which includes small insects. It pushes its closed bill into the hollow stem from the side, and then opens it with a great force which splits the stem. Thus it reaches small insects, grubs and spiders which are hiding inside the hollow, away from the ever searching eyes of predators.