A small flock of Brown-headed Cowbirds has taken up residence with my bison herd. Cowbirds are a native North American bird species that originally coexisted with the large bison herds in the Great Plains. Cowbirds like to eat the insects bison stir up around them while grazing and have developed a knack for moving around the giant animals without getting crushed.
Most normal birds reproduce by building a nest, laying eggs, hatching the eggs, and feeding the new-born chicks. However, because bison herds are frequently on the move and cowbirds depend on them for food, the birds have developed a somewhat different method of producing offspring. This method, called brood parasitism, involves secretly laying thier eggs in the nests of other birds who then unknowingly raise the young cowbirds as thier own.
When Europeans showed up in North America with cattle the cowbirds ready adapted and today, with cattle farming spanning from coast to coast, cowbirds have been able to expand thier range significantly.
