Dwindling genetic diversity in European ground squirrels?

Abstract

a b s t r a c tThe European ground squirrel (Spermophilus citellus) is endangered and in decline. Populations are increasingly fragmented, and only a coordinated conservation effort at the European level may guarantee its long-term survival. To obtain a general population genetic picture on a larger geographic scale, we screened 117 individuals from seven local populations in Hungary, Romania, and Austria for allelic variation at eleven microsatellite loci. We found a high (23.4%) proportion of private alleles, and a moderate to somewhat elevated level (15.27%) of partitioning of genetic diversity among populations, compared to that found in many other terrestrial mammals. Genetic variability was significantly higher than in earlier studied Czech populations that are considered genetically depleted, but significantly lower than in undisturbed populations of S. suslicus and S. brunneus, that are similar to the European ground squirrel in their ecological requirements, reproductive biology, and social organization. Genetic diversity was also lower than in most presumably "undisturbed" populations of other Sciurid species. This, together with the observed level and pattern of genetic differentiation among populations, such as no significant increase of genetic differentiation with geographic distance and similar variance of genetic differentiation between populations independent of geographic distance, indicated the prevalence of relatively strong drift effects for all populations. A Bayesian STRUCTURE analysis and a factorial correspondence analysis concordantly revealed a fairly complex genetic composition of local populations, but no major geographic trend in the pattern of the genetic composition. Overall, the results suggest disintegration of local colonies that might earlier have been more connected genetically. The STRUCTURE analysis also suggested anthropogenic translocations among single Hungarian populations. Our data on genetic diversity and its distribution do not object to such conservation measures. Translocation of individuals particularly from nearby populations may increase the chances of survival of small and isolated populations and counteract inbreeding at low densities.

Genetic variation and population structure in a threatened species, the Utah prairie dog Cynomys parvidens: the use of genetic data to inform conservation actions

“…); European ground squirrels ( Spermophilus citellus ; Ben Slimen et al. ; ] as well as narrowly distributed endemics [e.g., mouse lemur species ( Microcebus spp. ; Olivieri et al.…”

“…Under scenarios of global climate change, small isolated populations are likely to experience increased extinction probabilities due to reduced evolutionary potential (Peacock and Dochtermann 2012), which is dependent upon heritable genetic variation in adaptive traits (Naish and Hard 2008;Robinson et al 2008;Naish et al 2013;Olson et al 2013). The conservation genetics literature is replete with examples of habitat loss, fragmentation, and reductions in genetic variation from a wide variety of taxa including once widely dispersed species [e.g., mountain lion (Puma concolor; Ernest et al 2003); white rhinoceros (Ceratotherium simum; Nielsen et al 2008); Siberian flying squirrel (Pteromys volans; Lampila et al 2009); European ground squirrels (Spermophilus citellus;Ben Slimen et al 2012;] as well as narrowly distributed endemics [e.g., mouse lemur species (Microcebus spp. ; Olivieri et al 2008); Devils Hole pupfish (Cyprinodon diabolis; Martin et al 2012); and bluemask darter (Etheostoma akatulo; Robinson et al 2013)].…”

Spermophilus citellus(Rodentia: Sciuridae)

“…No evidence was found for contemporary selection on major histocompatibility genes (Říčanova´et al 2011). Another assessment of 117 individuals from Austria, Hungary, and Romania for 11 microsatellite loci revealed a high (23.4%) proportion of private alleles, presumably the result of disintegration of local populations that might have been historically connected genetically (Ben Slimen et al 2012). …”