This study will examine the role of red imported fire ants in reducing the reproductive performance, and thereby in affecting the social and mating system, of eastern bluebirds. Previous work has shown that the reproduction of bluebirds in Athens, Georgia, where the ants are established, is depressed compared to the reproduction of the same species in Clemson, South Carolina, where the ants have been absent. Now the ants are invading Clemson; this natural experiment will be used to test the hypothesis that the fire ants are the cause of decreased reproduction. Bluebird reproduction and social behavior will be monitored in the two sites. The Athens site will serve as a control for other kinds of environmental variation. If fire ants are the cause of lowered reproduction in Athens, then as they invade Clemson, bluebird reproduction should decline there, as well.
A new species invasion is like a stone thrown into a pond. How far do the ripples go, and how many distant relationships do they affect? This study will contribute to the general answer to this big question. It may be that the tendency of a male bird to guard his mate, and the rate at which his mate engages in extra-pair matings, is influenced by an invading ant species.
