Effects of extreme environmental conditions on white‐tailed deer antlers

Abstract

ABSTRACTAntler size and morphology is the resultant combination of deer age, nutrition, and genetics. Additionally, extreme environmental conditions can affect deer health, which may influence current and future antler metrics. Throughout the antler development season of 2012, the Nebraska, USA, white‐tailed deer (Odocoileus virginianus) herd experienced a combination of extreme environmental conditions including extreme drought and disease, which we hypothesized would negatively affect antler size and morphology. Our objectives were to evaluate whether 1) age‐specific antler metrics differed between deer stressed by an extreme environmental condition year compared with nonextreme condition years, and 2) subsequent age‐specific antler metrics of a cohort born during an extreme environmental condition year differed from those born during nonextreme condition years. We measured antler metrics on harvested white‐tailed deer from central Nebraska for an 8‐year period (2009–2016) that spanned the extreme environmental condition year. Over this same time period, we measured pedicle seal depth on naturally cast antlers. Some trends were apparent for specific antler metrics in particular age groups; but, overall, antler metrics measured from harvested deer were not consistently affected during the extreme environmental condition year. Conversely, pedicle seal depths responded to environmental stressors and were smaller during the extreme environmental condition year compared with nonextreme condition years. We found effects to persist for years following extreme environmental stress—antler metrics of the extreme environmental condition cohort were smaller compared with nonextreme years. These results suggest that stressors caused by extreme environmental conditions can affect deer health and be indexed using sensitive metrics taken on cast antlers. Furthermore, effects on antler metrics can persist, affecting subsequent antler expression for cohorts that experience extreme environmental conditions during their first year of life. © 2019 The Wildlife Society.