Releasing Montagu's harrier (Circus pygargus) by the method of hacking

  • Published source details Pomarol M. (1994) Releasing Montagu's harrier (Circus pygargus) by the method of hacking. Journal of Raptor Research, 28, 19-22.


This study is summarised as evidence for the following.

Action Category

Translocate raptors

Action Link
Bird Conservation
  1. Translocate raptors

    A replicated trial (Pomarol 1994) found that, of 87 Montagu’s harrier Circus pygargus fledglings released at a marshland site in southeast Spain between 1988 and 1992, 83% successfully established in the wild (from 66% of 29 birds released in 1992 to 100% of 13 birds released in 1988-9). A further six chicks died during their first flights at the release site. Birds were taken from recovery centres (mainly chicks rescued from agricultural fields) and agricultural fields in Spanish regions with large harrier populations. They were moved to an enclosure at the release site at 20-30 days old and fed there. Five to eight days later the enclosure was opened and the birds could leave. They were then fed until they reached independence (i.e. stopped returning to be fed), an average of 30-37 days after release, depending on the age at release.


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