Survival and Cause-Specific Mortality of Wild Turkeys in Northern Indiana

Abstract

Information regarding survival and cause-specific mortality of eastern wild turkeys (Meleagris gallopavo silvestris) is vital to their management, especially in small or isolated populations. Between January 2003 and August 2005, we used radio telemetry to investigate survival and cause-specific mortality of 87 [44 male (24 adult and 20 juvenile) and 43 female (34 adult and 9 juvenile)] wild turkeys in northern Indiana. We estimated annual and seasonal survival using the Kaplan-Meier product-limit method. Mean male and female annual survival estimates were 0.257 and 0.777, respectively. Annual survival estimates were different between sexes within years, but were homogenous within sexes between years. Survival estimates did not differ among seasons for either sex. However, differences in survival estimates between sexes were detected in the spring, fall and winter seasons. Hunter harvest (46.2% male mortality) and predation (33.3% female mortality) were the leading known causes of mortality for male and female wild turkeys, respectively. Predators (canids, birds and unknown mammals) were responsible for 28.6% of mortality for both sexes combined. Although predation on adult birds was not severe, high mortality of male turkeys in the form of legal spring harvest, in addition to other causes of mortality, warrants concern for small, exploited populations in highly fragmented landscapes like those of northern Indiana.