Dietary patterns of a generalist carnivore in West Virginia

Abstract

The proportion and diversity of prey species consumed by bobcats Lynx rufus is often correlated with prey abundances, individual skill level, environmental conditions, and habitat quality. Bobcats generally consume prey species that rely on mast – the fruits of trees – for basic life history requirements. In West Virginia forests, many mast-producing tree species have declined over the past 40 years, yet the last known study on bobcat diet in the state was in 1977. Thus, we need current data to understand the effects of forest compositional changes on bobcat dietary patterns. We evaluated stomach contents of 300 bobcats collected over the 2014–2015 (n = 150) and 2015–2016 (n = 150) hunting and trapping seasons in West Virginia. Simpson’s index of diversity indicated an 87% probability that two randomly selected prey items belong to different species, supporting the idea of bobcats as generalist carnivores. White-tailed deer Odocoileus virginianus (32%), mice and rats (30.7%), rabbits (21.3%), Virginia opossum Didelphis virginiana (18.7%), and squirrels (17.3%) occurred most frequently. We found 92% dietary overlap between sexes and 35% between stage classes. Deer, opossum, and raccoon Procyon lotor occurred more frequently in males, whereas rabbits occurred more frequently in females. Deer occurred more frequently in adults; raccoons in yearlings; and small rodents in juveniles. Overall occurrence of deer (-17.1%), rodents (-9.5%), opossum (+13.5%), and raccoon (+5.1%) differed significantly between the 1977 study and this study, which may allude to changes in the abundance of mast-dependent prey species over time. Similarly, hard mast (i.e., nuts) production had a significant interaction effect with study season on the overall occurrence of squirrels in bobcat diets. By improving our understanding of bobcat trophic interactions, we can better manage their populations and ecological communities by managing for the dietary requirements of their common prey species.