The Common Crow as a sentinel species of rabies in wildlife populations

Abstract

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Home range and foraging habitat of American Crows, Corvus brachyrhynchos, in a waterfowl breeding area in Manitoba

“…The analysis of flight distances complements our findings in a related study (Sullivan and Dinsmore 1990) in which rates of crow predation on artificial duck nests decreased markedly at distances greater than 700 m from crow nests. The longest flight from a nest reported by Schaefer (1983) was 4.8 km, compared to only 2.1 km in our study.…”

“…The mean breeding season home range area of crows in our study was 70% larger than for seven crow pairs in Iowa (Schaefer 1983) and nearly 300% larger than the largest territories of several groups of cooperatively breeding crows in Florida (Kilham 1989: 40).…”

“…Current knowledge of crow foraging is limited to studies of food habits (Kalmbach 1937;Young 1989) and factors affecting egg predation Beyersbergen 1986, 1987;Sullivan and Dinsmore 1990). Only two authors have investigated the daily movements of crows during the breeding season (Schaefer 1983;Kilham 1989), and none has described crow use of foraging habitats quantitatively.…”