A comparison and analysis of the post-release movement of four species of raptors

Includes bibliographical references (pages 39-41)Forty individuals of four species of raptors,\ud Cooper's Hawk (Accipiter cooperii), Red-tailed Hawk (Buteo\ud jamaicensis), American Kestrel (Falco sparverius), and\ud Prairie Falcon (Falco mexicanus) were released after a\ud conditioning period and monitored with the use of radio\ud telemetry. All birds were found to generally increase\ud their activity range over a period of time. Juveniles\ud always moved more than adults. Species that consumed\ud greater proportions of avian prey showed increased differences\ud between juvenile and adult movement suggesting\ud intraspecific predation and consequent adaptive significance\ud in increased juvenile movement. Cooper's Hawks\ud showed the greatest movement followed by American Kestrels\ud and then Prairie Falcons. Red-tailed Hawks showed least movement. In species where the sexes may winter together (Red-tailed Hawk and Cooper's Hawk), both sexes appeared to move the same amount. Both species of Falco had increased\ud male movement. The presence of the radio package\ud had no effect on the birds' activity as long as it remained\ud below 4% of the birds bodyweight. Modified falconry\ud techniques as a method of conditioning appeared to adequately\ud prepare each raptor for survival once released