The effects of prey depletion on the patch choice of foraging blue jays (Cyanocitta cristata)
نویسندگان
چکیده
Blue jays (Cyanocitta cristata) were trained to hunt for non-cryptic moths presented in projected images. On each trial, the jays chose one of two patches to hunt in: (1) a uniform, “non-depleting” patch with constant prey density of 0.25; or (2) a “depleting” patch in which prey density changed during the foraging bout. In the depleting patch, the initial prey density was 0.50, declining to zero in a single step part-way through each foraging bout (session). The patch choices of the jays were greatly affected by these conditions. The jays chose the depleting patch early in the session, and then switched to the uniform patch. They obtained nearly all of the prey available. Analysis of the events preceding switches between patches suggested that the jays used different rules to switch out of each of the two patches.
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