کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8971845 1552243 2005 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Evaluating temporal and spatial margins of safety in galahs
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Evaluating temporal and spatial margins of safety in galahs
چکیده انگلیسی
When approached by a potential predator, individuals must decide when to flee. Individuals could assess risk by monitoring their distance from an approaching threat or by monitoring the expected time that the predator would take to reach them. Theory predicts, and empirical studies support the hypothesis, that some species may maintain a temporal margin of safety and therefore monitor the expected time a predator would take to reach them. We systematically walked towards galahs, Cacatua roseicapilla, an Australian parrot, and varied our approach speed. If galahs maintain a temporal margin of safety, we expected them to flush at a greater distance in response to the fast approach. We found, however, no support for the temporal margin of safety hypothesis. Rather, we found evidence that galahs are sensitive to distance in a novel way: after being alerted, they flushed when humans approached to within 44% of the alert distance. Our result differs from traditional models of spatial margins of safety because it suggests that animals will take flight after being approached to within about half the alert distance. By doing so, individuals maintain a dynamic spatial margin of safety and may reduce costs associated with ongoing monitoring of predation risk.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Animal Behaviour - Volume 70, Issue 6, December 2005, Pages 1395-1399
نویسندگان
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