Land cover and space use influence coyote carnivory: evidence from stable-isotope analysis

For many species, the relationship between space use and diet composition is complex, with individuals adopting varying space use strategies such as territoriality to facilitate resource acquisition. Coyotes ( Canis latrans ) exhibit two disparate types of space use; defending mutually exclusive territories (residents) or moving nomadically across landscapes (transients). Resident coyotes have increased access to familiar food resources, thus improved foraging opportunities to compensate for the energetic costs of defending territories. Conversely, transients do not defend territories and are able to redirect energetic costs of territorial defense towards extensive movements in search of mates and breeding opportunities. These differences in space use attributed to different behavioral strategies likely in fl uence foraging and ultimately diet composition, but these relationships have not been well studied. We investigated diet composition of resident and transient coyotes in the southeastern United States by pairing individual space use patterns with analysis of stable carbon ( delta 13 C) and nitrogen ( delta 15 N) isotope values to assess diet. During 2016 - 2017, we monitored 41 coyotes (26 residents, 15 transients) with GPS radio -collars along the Savannah River area in the southeastern United States. We observed a canopy effect on delta 13 C values and little anthropogenic food in coyote diets, suggesting 13 C enrichment is likely more in fl uenced by reduced canopy cover than consumption of human foods. We also observed other land cover effects, such as agricultural cover and road density, on delta 15 N values as well as reduced space used by coyotes, suggesting that cover types and localized, resident -like space use can in fl uence the degree of carnivory in coyotes. Finally, diets and niche space did not differ between resident and transient coyotes despite differences observed in the proportional contribution of potential food sources to their diets. Although our stable isotope mixing models detected differences between the diets of resident and transient coyotes, both relied mostly on mammalian prey (52.8%, SD = 15.9 for residents, 42.0%, SD = 15.6 for transients). Resident coyotes consumed more game birds (21.3%, SD = 11.6 vs 13.7%, SD = 8.8) and less fruit (10.5%, SD = 6.9 vs 21.3%, SD = 10.7) and insects (7.2%, SD = 4.7 vs 14.3%, SD = 8.5) than did transients. Our fi ndings indicate that coyote populations fall on a feeding continuum of omnivory to carnivory in which variability in feeding strategies is in fl uenced by land cover characteristics and space use behaviors.