Research Methods in Life Sciences Commons^™

Using Stable Isotopes And Diet Analysis To Assess The Potential For Competition And Coexistence Among Coyotes (Canis Latransl, Red Foxes (Vulpes Vulpes), And Gray Foxes (Urocyon Cinereoargenteus) In Maine, Henry M. Masters

Student Scholarship

When two species compete for food, one species typically outcompetes the other. Subordinate species can alleviate costs of competition by reducing diet overlap, promoting coexistence. Non-native coyotes (Canis latrans) and historically native gray foxes (Urocyon cineroargenteus) have expanded their range in Maine and may compete with native red foxes (Vulpes vulpes). To investigate competition, I analyzed stable isotopes and stomach contents to determine if coyotes, red foxes, and gray foxes differed in use of anthropogenic foods and trophic position. I predicted that coyotes utilize anthropogenic foods the least (lowest δ13C), and red foxes utilize …