Efficacy of acclimating and releasing captive-reared and wild-translocated Northern bobwhites

Abstract

Northern bobwhite populations are dwindling across their range. Accordingly, in areas with bobwhite habitat restoration and no nearby populations, effective population restoration techniques are needed. Here, we evaluated three bobwhite restoration release strategies: (1) release of captive-reared bobwhites on sites with and without resident populations, (2) translocation of wild-trapped bobwhites from a region of high population density to a region with no population, and (3) release of captive-reared and wild-translocated bobwhites acclimated on site prior to release in year 2. Wild-translocated birds survived longer than captive-reared birds. Mean survival for captive-reared bobwhites was 2.42 weeks, and 4.27 weeks in year 1, and 1.91 and 1.40 weeks in year 2, for study sites without resident and with resident birds present, respectively. Mean survival for wild-translocated birds was 8.50 weeks in year 1, and 11.54 weeks in year 2. Wild-translocated birds dispersed shorter distances than captive-reared birds. Both captive-reared and wild-translocated bobwhites only nested on study sites with conspecifics. Captive-reared birds had 0 nesting attempts on the site with no resident bobwhites, and ⩾8 nests on the site with resident bobwhites. Wild-translocated females nested six times and were subsequently observed with juveniles. On-site acclimation did not increase post-release survival for northern bobwhites. Acclimation increased site fidelity but reduced survival for captive-reared birds and had no impact on survival for wild-translocated bobwhites. Population restoration by release of captive-reared or wild-translocated birds is not irrelevant, but further investigation is needed into the relationship between captive-reared birds and predators, and methods to increase survival and reproduction of released birds.