Survival and cause-specific mortality of the female eastern wild turkey at its northern range edge

Abstract

Context In an era of rapid environmental change, many species are shifting their distributions. As temperate-zone species’ expand their ranges north, different and potentially severe limiting factors may begin to affect their ability to survive and reproduce. The wild turkey (Meleagris gallopavo) is one example of a species undergoing rapid northern expansion. Aims An improved understanding of wild turkey demography at the species’ northern range periphery would facilitate effective management of this important game species. Therefore, we undertook a study to evaluate survival, causes of mortality, and behavioural strategies that may govern survival of female wild turkeys. Methods We captured 53 female wild turkeys, and used backpack transmitters to monitor their individual fates during 2012–13. Key results The annual survival estimate was 0.37 (95% CI: 0.25–0.55), with the lowest seasonal survival in the winter. The most frequent cause of mortality was mammalian predation, predominately by coyotes (Canis latrans). Age, proximity to supplemental food, and habitat use did not affect risk of mortality. Conclusions Northern wild turkeys in our study exhibited lower survival and suffered higher predation than did populations in the species’ historic range. Despite our findings, the wild turkey has expanded its range northwards and continues to exist in these peripheral areas. This may be due to high productivity or a source–sink dynamic, whereby high mortality is offset by immigration from the south. Implications The low survival and high predation of wild turkeys in the north must be considered when developing management strategies, particularly if interest exists in translocating turkeys farther north. Further research is needed to better understand whether northern turkey populations persist as sinks.