Evaluation of translocation criteria: Case study with trumpeter swans (Cygnus buccinator)

Abstract

Translocations are a common conservation technique; however, the feasibility and success of translocations are evaluated rarely. We translocated 57 trumpeter swans (Cygnus buccinator) from Idaho to Utah during 1996 to encourage migration to more southern wintering areas. We evaluated the feasibility and success of the translocation by studying biological and socio-political criteria prior to and during the translocation. Lack of support from governmental and non-governmental agencies did not allow additional translocations in subsequent years. Additional releases are needed, however, to increase the probability of swan returns to the release area. Our evaluation explores the possibility that trumpeter swans may be more vulnerable to hunting than tundra swans (Cygnus columbianus); however, we still lack conclusive empirical evidence that shows a negative effect of tundra swan hunting on the survival of trumpeter swans migrating through Utah. Finally, some elements of the local public have been negatively impacted by the translocation owing to restrictions imposed on tundra swan hunting and season closures. To ensure the success of trumpeter swan translocations planned as early as the year 2000, all translocation criteria need to be supported before as well as during the translocation. (C) 2000 Elsevier Science Ltd.