Data from: Using relatedness networks to infer contemporary dispersal: application to the endangered mammal Galemys pyrenaicus

Information about the degree of contemporary dispersal is important when trying to understand how populations interchange individuals and identify the specific barriers that prevent these movements. In the case of endangered species, this can represent crucial information when designing appropriate strategies that favor natural genetic exchange between populations. Here we analyze the parentage relationships between individuals from different localities and use these data to infer dispersal occurred in recent generations. We applied this approach to the Pyrenean desman (Galemys pyrenaicus), a semiaquatic and endangered species endemic to the Iberian Peninsula. We studied this species in four primary rivers in the Iberian Range, where two ancient mitochondrial lineages are separated by a strict contact zone but whose populations are more homogeneous at the genome level, suggesting the existence of complex dispersal patterns. Using next generation sequencing, we obtained 912 SNPs from each sample and estimated relatedness values between them. While relatedness networks were very dense within each river, we found surprisingly few relationships between individuals from different rivers despite their close proximity in some cases, indicating that dispersal between rivers is extremely low compared to dispersal within a single river. In agreement with this, the degree of inbreeding was exceedingly high in most individuals. These data show that relatedness information can be crucial to understand the contemporary dispersal patterns and conservation status of specific populations of endangered species.