Reintroducing the osprey to Switzerland, one century after its disappearance as a breeding species

Summary

The osprey (Pandion haliaetus) last bred in Switzerland in 1911 and is listed as Regionally Extinct in the Swiss Red Data Book, though globally of Least Concern. In 2015, exactly a century after its disappearance, the bird society Nos Oiseaux launched a reintroduction in the Trois-Lacs region of the Canton of Fribourg, aiming to restore a viable breeding population and use the species as a flagship for wetland and forest conservation. Because ospreys cannot be bred in captivity, chicks were collected from wild nests: an initial six from Scotland with reintroduction specialist Roy Dennis in 2015, then annual collections of six chicks from Sachsen-Anhalt, Germany and up to 12 from Østfold, Norway, each for a five-year period, chosen to build genetic diversity and provide a safety net if one source country had a poor breeding season. Chicks were transported by car or plane under CITES and veterinary permits to a release site inside the State Prison of Bellechasse, which offered security and in-kind support including release aviaries. By 2017, 30 of a planned 60-plus chicks had been released, all ringed and fitted with lightweight tail-mounted transmitters (rather than heavier backpack units, to avoid raising chick mortality), with 27 of the 30 successfully migrating. Major hurdles included convincing skeptical ornithologists the project was necessary, securing international permits, and neutralizing dangerous electricity pylons near the release site. The project rates itself successful so far, noting that comparable osprey reintroductions elsewhere in Europe have all led to established breeding populations, with the first Swiss returns anticipated in 2018.