Laying the ground for the evolutionary adaptive conservation of the endangered Darwin's fox (Lycalopex fulvipes)

Darwin's fox ( Lycalopex fulvipes ) is one of the most narrowly distributed and endangered carnivores in the world. Until new records began to be collected in 2012, the species was known to occur only on Chiloé Island and the Nahuelbuta mountain range on the mainland. Here, we genotype the partial mitochondrial DNA control region, 11 microsatellite loci, and exon 2 and exon 3 of major histocompatibility complex class II to assess the genetic structure and variation of Darwin's foxes ( n = 105) from all known localities, with 99 samples collected from the previously known populations and six from new localities where the species has been recorded. We found low genetic diversity, with six mitochondrial DNA haplotypes that were unevenly distributed across the population, strong microsatellite fixation and only one and two polymorphic loci in nuclear genes, respectively, raising major concern regarding susceptibility to infectious diseases. Genetic diversity was markedly lower on Chiloé than on the mainland, which hints at an interplay of founder effect and lack of gene flow following isolation other than small population size. The latter is a concern for the mainland counterpart, where it is compounded by high fragmentation. Since genetic data qualify these two populations as separate management units, conservations actions should be envisaged pertinently. Restoring and further enhancing the connectivity of mainland population is a priority. Based on the findings of this study, a reassessment of its IUCN conservation status, which is currently “Endangered”, might be urgently needed.