Abstract

Following the use of Barnacle Geese Branta leucopsis as foster parents in a conservation program for the endangered Lesser White-fronted Goose Anser erythropus in Sweden 1981–1999, mixed breeding pairs of the two species were established in the wild. We find indications that this was related to shared moulting habits of the two species in the Bothnian Sea during late 1990s. Starting in 2003, five mixed pairs produced at least 49 free-flying hybrid offspring until 2013, when the last breeding was confirmed. Reported numbers of hybrids did not increase in parallel to the production of young hybrids over time. After 2013, the number of hybrids started to decrease in Sweden and the Netherlands. Lower numbers of hybrids than expected can partly be explained by management actions taken, but may also be associated with low survival due to genetic outbreeding. Mixed pairs and their offspring entirely adopted the migratory habits of Barnacle Geese, overlapping very little with sites used by Lesser White-fronted Geese. We find no evidence that the hybrids ever posed a serious threat to Lesser White-fronted Geese breeding in Fennoscandia.

Keywords

translocation; intergeneric hybrid; distribution; wintering grounds; migration route; Anatidae

Published in

Ornis Svecica
2021, Volume: 31, pages: 125-138

SLU Authors

• Liljebäck, Niklas

  • Department of Ecology, Swedish University of Agricultural Sciences
    

• Månsson, Johan

  • Department of Ecology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Fish and Wildlife Management
Ecology


Publication identifier

DOI: https://doi.org/10.34080/OS.V31.22430

Permanent link to this page (URI)

https://res.slu.se/id/publ/123875