Interannual Variability in Survival Rates for Adult Female White‐Tailed Deer

Abstract

ABSTRACTAdult female survival is an important component to population models and management programs for white‐tailed deer (Odocoileus virginianus), but short‐term survival studies (1–3 yrs) may not accurately reflect the variation in interannual survival, which could alter management decisions. We monitored annual survival and cause‐specific mortality rates of adult female white‐tailed deer (n = 158) for 6 years (2010–2012, 2016–2018) in southern Delaware, USA. Annual survival rate differed among years. Survival rates (±SE) and mortality causes were similar in 3 years (2011 = 0.72 ± 0.08, 2017 = 0.68 ± 0.08, 2018 = 0.74 ± 0.09) and comparable to previous research from mixed forest‐agricultural landscapes. A relatively low survival rate in 2010 (0.48 ± 0.11) was influenced by hunter harvest and potentially compounded by abnormally severe winter conditions in the prior year. A peracute outbreak of hemorrhagic disease occurred during summer 2012, resulting in an annual survival rate of 0.38 ± 0.11, and to our knowledge is the first reported case of a hemorrhagic disease outbreak in a monitored wild population with known fates. In 2016, we did not observe any harvest mortality, resulting in high annual survival (0.96 ± 0.04). Our results demonstrate the degree of variability in annual survival and cause‐specific mortality rates within a population. We caution against the use of short‐term survival studies to inform management decisions, particularly when incorporating survival data into population models or when setting harvest objectives. © 2020 The Wildlife Society.