Cowbirds and Brood parasitism

KZYX The Ecology Hour

Birds invest considerable effort in the reproductive processes and have evolved myriad ways to improve their chances of success. The entire process of mating, nest-building, brooding, and rearing young consumes enormous amounts of energy, often leaving the parent birds nearly worn-out by the time their young reach independence. It is perhaps no wonder, then, that a few birds have developed a way to avoid most of that expense by getting other birds to do most of the work. Brood parasites lay their eggs in the nests of other birds, which then hatch and rear them unwittingly.

The most widespread and abundant brood parasite in North America is the Brown-headed Cowbird. Dr. Mark Hauber studies Cowbirds and other brood parasites around the world, focusing on questions of recognition, social function, and the complex interactions between the parasites and their victims. He is a Professor at the University of Illinois in the Department of Animal Biology, School of Integrative Biology, where he runs the “Cowbird Lab” and conducts some fascinating research. He is also Harley Jones Van Cleave Professor of Host-Parasite Interactions in the Department of Evolution, Ecology, and Behavior. Dr Hauber addressed the central question of recognition: How does a Cowbird chick, raised entirely by another species, know it is a Cowbird?