Factors Influencing White-Tailed Deer Mortality Risk within a Multi-Predator System in Michigan, USA

I monitored cause-specific mortality and factors influencing mortality risk for white-tailed deer in the Upper Peninsula of Michigan, USA, during two high mortality risk periods: adult female deer during Feb–May, and fawns from birth to 6 months. I observed high rates of predation and starvation for adult female deer during Apr–May, suggesting that late winter represents a survival bottleneck due to nutritional declines. A strong negative relationship existed between snow free days during late winter and mortality risk. Predation was the dominant mortality source for fawns but predation risk decreased with larger birth mass. Black bears and coyotes accounted for most fawn kills at the population level, but wolves and bobcats had greatest per-individual fawn kill rates. My results suggest predation was the dominant mortality source for fawns and adult female deer, but multiple predator species were important and nutritional condition of deer influenced their vulnerability to predation