eWestern BirdsThe Quarterly Journal of Western Field Ornithologists
Vol. 38, No. 4
Western Field Ornithologists
Insects Predominate in Peregrine Falcon Predation Attempts in Arizona
David H. Ellis, Charles T. LaRue, James K. Fackler, and R. Wayne Nelson
ABSTRACT: We compare two methods of collecting data on food habits (observations of predation attempts [n = 131] and analysis of prey remains at eyries [n = 809]) for Peregrine Falcons (Falco peregrinus) in Arizona. White-throated Swifts (Aeronautes saxatalis) were pursued in at least 38% of the predation attempts on birds but constituted 22% of the avian diet (by number) from prey remains. Insects constituted 1% of prey remains from eyries but were targets in 69% of observed attacks on prey. Insects, primarily cicadas (Cicadidae), were especially important numerically to breeding females guarding their nest cliffs. These observations suggest that insects may be much more important than formerly supposed in the Peregrine Falcon’s diet in other regions when and where large insects are aloft.