Predation of birds at feeders in winter

Source: Dunn, EH; Tessaglia, DL Journal of Field Ornithology Vol. 65, no. 1, pp. 8-16, 1994
In this article the risk of birds being predated while in the neighborhood of a bird feeder is described.
A continentwide survey of homes with bird feeders produced 567 reports documenting 1138 incidents of predation. Of the 25 species of predators recorded, three (Sharp-shinned Hawk, Accipiter striatus; domestic cat; Cooper's Hawk, A cooperii) were responsible for 80% of the incidents in which the predator was known. Ten of the 62 species of prey identified accounted for 92% of all victims. The birds most vulnerable to predation were those that commonly occur at feeders throughout the continent (i.e., the most widespread species), but additionally, flocking species were more vulnerable to avian predators than more solitary ones. Prey size was correlated to size of avian predators, but cats concentrated on small birds. Hawks were attracted to feeders with particularly high levels of bird activity, but cats were not. The bird-feeding environment does not appear to expose birds to a higher risk of predation than is encountered in the absence of feeders.