Eastern Towhee - Predators

Predators

Many animals prey on eastern towhees and their eggs, including reptiles, mammals, and birds. A literature review summarizes several reports demonstrating that predators are a major cause of nest failure. The highest nest predation rate noted was 88% in a New York study. Mammals that are likely nest predators include northern raccoons (Procyon lotor), domestic cats (Felis catus), and eastern chipmunks (Tamias striatus). Snakes such as bullsnakes (Pituophis catenifer), rat snakes (Elaphe spp.) and garter snakes (Thamnophis spp.) have been reported eating eastern towhee eggs. Weasels (Mustela spp.) and blue jays (Cyanocitta cristata) are also likely nest predators. Several birds are known to prey on adult eastern towhees, including short-tailed (Buteo brachyurus), sharp-shinned (Accipiter striatus) and Cooper's hawks (Accipiter cooperii). At least some mammals also feed on adult eastern towhees. In Maryland, an eastern towhee was found in the stomach contents of a red fox (Vulpes vulpes).

Brown-headed cowbirds (Molothrus ater) parasitize eastern towhee nests. In a South Carolina old field 5 of 19 eastern towhee nests were parasitized. Each parasitized nest contained 1 brown-headed cowbird egg. The desertion rate for parasitized nests was 20%, which was similar to nests that had not been parasitized (21%). Two of the five brown-headed cowbird eggs produced fledglings. The study did not determine if there was a difference in nest success between parasitized and nonparasitized nests. In West Virginia, only 3 of 41 eastern towhee nests were parasitized by the brown-headed cowbird. Average number of fledged young in nonparasitized nests was 2.8, which was similar to the average of 2.7 fledglings per parasitized nest. In a Pennsylvania study site, only 2 of 36 nests were parasitized and both produced eastern towhee fledglings. In a study of nest parasitism on Sanibel Island, none of 5 eastern towhee nests found were parasitized.