DENSITY-DEPENDENT HOME RANGE SIZE IN A RECOVERING POPULATION OF ISLAND FOXES (UROCYON LITTORALIS) ON SANTA ROSA ISLAND, CALIFORNIA

Katie B Elder; California Polytechnic State University, San Luis Obispo; kaelder@calpoly.edu; Juliann Schamel, John Perrine, Brian Cypher, Tim Bean

The island fox (Urocyon littoralis) is endemic to the California Channel Islands. The species experienced a dramatic population decline to near extinction followed by rapid recovery over the past thirty years. These drastic fluctuations in population size make the island fox an excellent candidate for studying the effects of density on home range size and habitat selection. In 2010, when density was historically low, researchers on Santa Rosa Island documented male fox home ranges on the eastern portion of the island. Beginning in 2022, with the fox population now at carrying capacity, we tracked the locations of 15 adult male foxes using GPS collars in a similar study area to compare their home range size, characteristics and overlap. Preliminarily, we found that island foxes display negative density dependent effects on home range size. Future work will include a finer scale look at fox habitat selection in both time periods to inform management decisions for this iconic species.

Mammals III: Canids   Student Paper InPerson Presentation