Genetic characterization of kit foxes at their northern range extent and monitoring recommendations

Abstract

ABSTRACT The kit fox (Vulpes macrotis) appears to be in decline in the northernmost and other peripheral portions of its range, yet its abundance, genetic diversity, and connectivity to core populations are unknown. We used 16 microsatellites and a sex marker to characterize population size and genetic diversity of the northernmost population in southeastern Oregon, USA, which we compared with a core population to the south. We identified 20 individuals from southeastern Oregon, sampled an average of 1.7 times each, resulting in a population size estimate of 28 (95% CI = 20–39) individuals on the study area. We estimated the genetic effective population size of the Oregon population at 14.7 (95% CI = 10.2–22.4) breeding individuals, which was <50% that estimated for the California, USA, core population. Relative to the core population, Oregon kit foxes exhibited similar heterozygosity but a deficiency in the number of alleles, which was consistent with a recent population decline. The use of 16 loci and a sex marker in this study enabled us to construct pedigrees, which provided insights about spatial organization of family groups and long distance dispersal. Continued monitoring of this peripheral Oregon population is essential to an effective conservation plan and noninvasive genetic methods are likely to provide the most effective means of doing so. Use of large numbers of markers will enable pedigree reconstruction to be integrated into such a program to obtain estimates of demographic parameters, habitat quality, and expansion–contraction dynamics in addition to abundance. © 2018 The Wildlife Society.

Keywords

• effective population size
• genetic structure
• kit fox
• microsatellites
• mitochondrial
• Oregon