Kleptoparasitism by bald eagles wintering in south-central Nebraska

Dennis G. Jorde; G.R. Lingle

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USGS · 1001515

Kleptoparasitism by bald eagles wintering in south-central Nebraska

Dennis G. Jorde·G.R. Lingle

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Abstract

Kleptoparasitism on other raptors was one means by which Bald Eagles (Haliaeetus leucocephalus) secured food along the North Platte and Platte rivers during the winters of 1978-1980. Species kelptoparasitized were Ferruginous Hawk (Buteo regalis), Red-tailed Hawk (B. jamaicensis), Rough-legged Hawk (B. lagopus), Golden Eagle (Aquila chrysaetos), and Bald Eagle. Stealing of prey occurred more often during the severe winter of 1978-1979 when ice cover restricted eagles from feeding on fish than during the milder winter of 1979-1980. Kleptoparasitism occurred principally in agricultural habitats where large numbers of Mallards (Anas platyrhynchos) were foraging. Subadults watched adults steal food and participated in food-stealing with adults, which indicated interspecific kleptoparasitism may be a learned behavior. We suggest factors that may favor interspecific kleptoparasitism as a foraging strategy of Bald Eagles in obtaining waterfowl during severe winters.

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Journal of Field Ornithology Article

Source-reported bounding extent: 39.926588421909436° to 40.93011520598305° latitude; -99.68994140625° to -98.173828125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Dennis G. Jorde, G.R. Lingle. 1988. Kleptoparasitism by bald eagles wintering in south-central Nebraska. https://pubs.usgs.gov/publication/1001515

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