Geese, swans and eagles are known for having only one mate until one of them dies. This practice is unusual in the birding world even though most birds are monogamous for at least one breeding season. Recent research has shown that even monogamous birds may bond with another bird that is not its partner to enhance its breeding success.

Some birds, such as House Wrens and hummingbirds, have multiple mates. This practice is rare, occurring in only about 2 percent of bird species. And when it does happen, it generally is difficult for the male to provide proper care for all of his broods. The males are most successful at this in habitats that are rich in resources.

After hummingbirds mate, the male will court and mate with another female. Females raise the babies alone. Closely related species of hummingbirds will mate with each other with crosses occurring between Anna’s and Costa’s hummingbirds.

House Wrens build multiple nests and let the female choose the one she prefers. After they mate, the male may try to attract another female to occupy one of the other nests he’s built. Then the male will divide his time trying to help raise multiple families at once.

Keep an eye on your backyard and tell us about the bird families you see!