Age-dependent genetic structure of arctic foxes in Svalbard

Abstract

Arctic foxes are highly mobile arctic predators with a very weak population genetic structure over large parts of their range. Less is, however, known about the more local genetic structure within regions. Here, we analyze genotypes at 12 microsatellite loci for 561 arctic foxes trapped in the high-arctic archipelago Svalbard and investigate the genetic structure in three different age classes. Significant linkage disequilibrium, deficit of heterozygotes, genetic differentiation, and a decrease in relatedness with distance among animals trapped in their first winter suggested that some litter mates remain in proximity of each other during the first winter. This pattern was stronger for females than for males, indicating male-biased juvenile dispersal, and weaker for older animals. There was no genetic differentiation among adult foxes harvested in different hunting areas. The foxes from the protected area around Hornsund were however more differentiated than expected based on geographic distance alone, suggesting a possible disrupting effect of harvest on the spatial genetic structure in the rest of Svalbard. Our results also indicated a possible kin structure among adult females, suggesting natal philopatry, but further investigations will be needed to reach firm conclusions concerning kin structure in arctic foxes.

Red foxes colonizing the tundra: genetic analysis as a tool for population management

“…Levels of relatedness may influence dispersal decisions and boreal red foxes may thus be more prone to emerge to the tundra if following a close relative. In the closely related arctic fox, presence of cohort-specific kin structure has been identified (Ehrich et al 2012) and synchronized long distance dispersal by closely related, young males has been recorded (unpublished data). Male-biased kin structures have been documented in canid species such Gottelli et al 2013) and, under specific demographic conditions, in the bateared fox (Otocyon megalotis; Kamler et al 2013).…”

“…Furthermore, the decision to disperse and establish in a novel habitat may be further influenced by sex-specific dispersal patterns and/or social factors (Lawson-Handley and Perrin 2007). A preference for establishing in territories adjacent to close relatives, or synchronize dispersal with close relatives have been documented in a closely related species (Ehrich et al 2012;Elmhagen et al 2015). It is however not known how these factors influence to the ongoing red fox invasion of the Fennoscandian tundra, but it is possible that there may be a higher occurrence of close relatives in the expansion front.…”

Population structure of two rabies hosts relative to the known distribution of rabies virus variants in Alaska

“…), although kin structure in arctic foxes in Svalbard has been suggested (Ehrich et al . ). Arctic foxes, especially those without access to year‐round marine resources, are known to travel long distances over sea ice in search of food in winter (Pamperin et al .…”

Reproductive responses to spatial and temporal prey availability in a coastal Arctic fox population

“…Both low pregnancy rate and low juvenile survival may suggest that the Arctic fox population at Svalbard is a saturated population with few vacant territories available for yearlings and young animals; limiting their ability to establish and reproduce as well as limiting their access to necessary food resources. Furthermore, our finding that a low proportion of the locally produced pups were trapped locally even though a relatively high number of pups were trapped each year, and the weak population genetic structure in the Arctic fox population on Svalbard suggests high juvenile immigration/emigration rates (Ehrich, Charmichael & Fuglei 2012). This may be due to high competition for territories causing a lot of movement in the population.…”