High post-release survival of hacked peregrine falcons Falco peregrinus at a river cliff site in Iowa, USA

  • Published source details Powell L.A., Calvert D.J., Barry I.M. & Washburn L. (2002) Post-fledging survival and dispersal of peregrine falcons during a restoration project. Journal of Raptor Research, 36, 176-182


This study is summarised as evidence for the following.

Action Category

Release captive-bred individuals into the wild to restore or augment wild populations of raptors

Action Link
Bird Conservation
  1. Release captive-bred individuals into the wild to restore or augment wild populations of raptors

    A study in the summers of 1999-2000 at a river cliff site in Iowa, USA (Powell et al. 2002), found that two week survival of 38 (21 in 1999, 17 in 2000) juvenile peregrine falcons Falco peregrinus released through hacking was between 74% and 89%, with overall weekly survival estimated at 98.8%. Movement away from the release site was higher in 2000, possibly due to the large numbers of great horned owls Bubo virginianus seen in the area (although no mortalities were due to owl predation).


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