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Coyotes (Canis latrans) colonized the eastern United States over the last century and formed a 3-species predator guild with bobcats (Lynx rufus) and gray foxes (Urocyon cinereoargenteus) across much of the southeastern United States. Diets among the three species vary along with respective impacts on game species such as white-tailed deer (Odocoileus virginianus) and wild turkeys (Meleagris gallopavo). To determine predation impacts on vertebrate prey and dietary overlap in consumption of prey items, we assessed diets of coyote, bobcat, and gray fox during spring, coinciding with white-tailed deer fawning and wild turkey nesting and brood rearing. We sampled across three sites along the Savannah River in South Carolina from mid-May through mid-June of 2020–2021. We collected 180 scat samples along 295.9 kilometers (71.1–122.4 km/site) of unpaved secondary roads and used DNA metabarcoding to determine vertebrate diet items. We identified predator species of scat using DNA metabarcoding and species-specific mtDNA fragment analysis (153 were coyote, 20 bobcat, and seven gray fox). Overall, we found evidence that two species, coyote and bobcat, consumed deer while all three consumed turkeys. Frequency of deer in the diet varied across sites for coyotes from 62–86% and wild turkey was present with a frequency of occurrence of 9% for coyotes, 5% for bobcats, and 14% for gray fox. Vertebrate diet specialization was evident across predator species with high frequency of deer in coyote diets, rabbits and small mammals in bobcat diets, and herpetofauna in gray fox diets. During deer fawning and wild turkey nesting and brood rearing, dietary overlap appears to be mediated by disparate selection of prey items, which reduced competition among coyotes, bobcats, and gray foxes. Use of DNA metabarcoding may augment our understanding of dietary preferences within this predator guild by providing increased resolution of diet composition among important game species. [ABSTRACT FROM AUTHOR]

Molecular data have been used to show northward post-Pleistocene range expansions from a refugium in the southeastern United States for several mammal species. Fossil and historical records indicate that gray foxes (Urocyon cinereoargenteus) were not present in the northeastern United States until well after the Pleistocene (ca. 900). To test the hypothesis that gray foxes experienced a post-Pleistocene range expansion we conducted a phylogeographic analysis of gray foxes from across the eastern United States. We sequenced a variable portion of the mitochondrial control region (411 base pairs) from 229 gray fox tissue samples from 15 states, representing the range of all 3 East Coast subspecies. Phylogeographic analyses indicated no clear pattern of genetic structuring of gray fox haplotypes across most of the eastern United States. However, when haplotype frequencies were subdivided into a northeastern and a southern region, we detected a strong signal of differentiation between the Northeast and the rest of the eastern United States. Indicators of molecular diversity and tests for demographic expansion confirmed this division and suggested a very recent expansion of gray foxes into the northeastern states. Our results support the hypothesis that gray foxes 1st colonized the Northeast during a historical period of hemisphere-wide warming, which coincided with the range expansion of deciduous forest. We present the 1st study that analyzes the phylogeographic patterns of the gray fox in the eastern United States. [ABSTRACT FROM AUTHOR]