Search tactics of a pause-travel predator: adaptive adjustments of perching times and move distances by hawk owls (Surnia ulula)

  title={Search tactics of a pause-travel predator: adaptive adjustments of perching times and move distances by hawk owls (Surnia ulula)},
  author={Geir A. Sonerud},
  journal={Behavioral Ecology and Sociobiology},
  • G. Sonerud
  • Published 1 April 1992
  • Environmental Science
  • Behavioral Ecology and Sociobiology
SummaryAfter having erected artificial perches of different heights in a clear-cut, I studied the effect of perching height on the allocation of search and pursuit effort of 9 individuals of the hawk owl. Hawk owls are diurnal and locate their small mammal prey visually. Horizontal attack and move distances increased with perching height in most individual cases, as well as across cases. Prey detection and giving-up times increased with perching height in half of the individual cases, but not… 
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