Association between weather and Dall's sheep Ovis dalli dalli harvest success in Alaska

Although extensive research has been conducted on a variety of factors that influence wildlife harvest rates, few studies have quantified the impact of weather on harvest success. As global warming continues to contribute to unprecedented changes in local weather regimes, particularly in arctic and alpine ecosystems, understanding how these changes impact human–wildlife interactions will become increasingly important and relevant for wildlife managers. Therefore, we used a long-term dataset (1999–2015) on Dall's sheep Ovis dalli dalli, an alpine species in Alaska, USA, as a case study to explore how changes in local daily weather has affected hunter harvest success. We used generalized linear mixed models to estimate relationships between daily harvest count and weather variables using three separate models; all hunters, resident hunters and non-resident hunters. Weather variables included daily mean relative humidity, precipitation, air temperature and wind speed. For our model including all hunters, which excluded wind, we estimated that a mean increase in relative humidity, precipitation and temperature from one day to the next resulted in an 11.7, 4.3 and 2.9% decrease in daily harvest, respectively. The effect of relative humidity influenced harvest count two to three times more than all other weather variables across models. This study contributes to a limited body of knowledge on quantifying the impact of weather on harvest success and about how changes in weather affect hunter and wildlife behavior. Advancing knowledge on how weather influences variation in harvest may facilitate effective strategies for adapting hunting regulations to meet harvest and population goals.