Abstract - Variability in the Responses of Black-billed Magpies
to Natural Predators Buitron, D. 1983. Variability in the
responses of black-billed magpies to natural predators.
Behaviour 87. pp. 209-233. Encounters between black-billed
magpies (Pica pica) and a variety of natural predators were
observed during 3 breeding seasons in Wind Cave National Park,
South Dakota. Raptors were the most frequently encountered
potential predators, with magpies reacting more strongly to
falcons than to hawks. Reactions to crows and squirrels were
most frequent and intense during laying and incubation, while
raptors in flight and coyotes were responded to most vigorously
during the second half of the nestling period and the first two
weeks of fledging. Perched raptors were almost always mobbed
vigorously. Diving to within 2 inches of a predator appeared to
be effective in driving it away. The roles of chasing and alarm
calling were less clear, but in addition to alerting mates and
offspring to danger, such behavior would i