Long distance spruce grouse translocations as an effective means of population recovery in New York

Abstract

AbstractSpecies translocations can be an effective tool for population recovery. The spruce grouse (Falcipennis canadensis) is rare at the southeastern extent of its range. In New York, USA, it is endangered, having a geographic range that has decreased more than 70% since 1977 and a remaining population with relatively low genetic diversity. We explored the efficacy of a translocation program by releasing 144 female, 19 male, and 291 young‐of‐year wild‐caught spruce grouse from Canada and Maine, USA, into occupied lowland boreal forest patches in New York from 2013–2019. We radio‐monitored 121 translocated and 93 resident (i.e., New York‐origin) adult grouse and evaluated movements, home range sizes, productivity, and survivorship of both groups. Translocated grouse generally moved nondirectionally across the landscape after release, remaining in the same boreal forest patch or an adjacent patch. Translocated grouse home ranges were stable but were double the area of resident grouse. Clutch and brood sizes of females the season following translocation were similar to resident grouse. Minimizing stress from handling and housing was of paramount importance for successful translocation; grouse held captive in enclosures with natural vegetation for ≤5 days had double the mean annual survivorship of captive grouse held for 6–10 days. One group held captive for 15 days had annual survivorship that approached zero. Translocated grouse that were handled the shortest duration had 72% of the mean annual survivorship of resident grouse. Similarity of life‐history parameters among groups suggests that translocations of wild‐caught galliforms into shrinking populations at range margins may be an effective means of augmenting population numbers and could be a useful tool for reversing declines and promoting population recovery. Long‐term success of spruce grouse translocations with a goal of population recovery in New York may hinge on survivorship meeting target estimates defined in population viability analyses or by the adjustment of target translocation numbers to compensate.