When the female cowbird lays her egg in the nest, she also removes one or two warbler eggs from the nest. Generally, she takes out more eggs than she puts in the nest. When throwing away eggs, she ...

A female cowbird may choose a bird nest for her uninvited egg in three ways. During the early breeding season she may choose a high perch from which to watch for nest-building activities by other ...

DEAR JOAN: A California towhee has built a nest in our jasmine bush. She laid three eggs about one week ago. Now we look in the nest and there is a fourth egg and it sure looks like a cowbird egg.

Because cowbird eggs require a shorter incubation period, and female cowbirds can lay more eggs than most wild birds, their chances of survival in host nests surpass those of the host’s own young.

Brown-headed cowbird eggs have been found in the nests of 221 North American songbird species. There are six cowbird species in the Western Hemisphere, three in the U.S. — brown-headed, ...

Among that 1% of birds, the cowbird is especially notorious — most brood parasites only leave their eggs in the nest of one type of bird, but the cowbird is a generalist, laying eggs in over 200 ...

Cowbird Eggshells Dropped From Above Break Other Birds' Eggs. Published May 10, 2018 at 11:41 AM EDT Updated May 10, 2018 at 3:51 PM EDT.

Black birds with a greenish sheen and brown heads sometimes visit my yard during spring migration. These are male brown-headed cowbirds, and they often arrive in mixed flocks of red-winged blackbirds ...

One species that gets a bad rap, through no fault of its own, is the brown-headed cowbird. The female cowbird lays its eggs in the nests of other species and then leaves forever.

Bird eggs sport an amazing variety of sizes, colors, and shapes. Their colors could fill an artist’s palette, from robin's ...

A female cowbird may choose a bird nest for her uninvited egg in three ways. During the early breeding season she may choose a high perch from which to watch for nest-building activities by other ...