The Feeding Ecology of Non-Native Red Fox (Vulpes vulpes) on an Atlantic Barrier Island

Baglieri, Maria

Abstract: The Red Fox (Vulpes vulpes) is a non-native predator inhabiting most of North America and its dynamic ecosystems, such as Fire Island National Seashore (FINS), New York - an Atlantic Barrier Island that has more than 330 species of birds that are both migratory and resident. Almost nothing is known about red fox food habits on Atlantic Barrier islands. Therefore, our objectives were to assess red fox diet on FINS and compares diet between residential and “designated” wilderness areas and also to test for differences in diet among seasons. It was hypothesized that the increased decline of endangered and threatened birds is due to consumption by the red fox. Red fox feces were collected from February 2011 to October 2012.There were 90 red fox feces samples collected, washed, and dried. Prey items were classified into 6 major categories including: mammal, avian, crustacean, plant, fish, and unknown (with unknown being particles of soil and debris). Mammalian bones were identified to the species level, avian bones were identified to order and family, fish were identified to class, plants were identified to kingdom, and crustaceans were identified to subphylum. Based on a Binary Logistic Regression, there is no significant relationship between mammalian or avian prey selection with respect to season (fall, winter, spring, summer) or location (wilderness vs. residential) [p-values=0.619 & 0.569, respectively]. Red fox diet differed significantly with respect to mammalian prey items between 2011 and 2012 [p-value=0.030], with more mammalian prey consumed in 2011.There is no significant relationship with respect to avian prey selection and year (2011 & 2012) or location (wilderness vs. residential) [p-value=0.942]. No threatened or endangered birds were detected in or samples. This study is the first complete study on the diet of red fox inhabiting a dynamic barrier island and will be a valuable tool in creating a management plan for sensitive island ecosystems.