Conservation genetics of a threatened amphibian, Bombina variegata, in northern Rhineland-Palatinate

In Germany, the yellow-bellied toad, Bombina variegata, is threatened and strictly protected. We studied the genetic population structure and diversity of this amphibian species inhabiting a low mountain range, the Westerwald in northern RhinelandPalatinate. This is one of the northernmost regions where Bombina variegata is widely distributed, thus serving as an important reservoir for (re)colonisation. Population connectivity and genetic diversity of 200 specimens belonging to seven sites (200-450 m a.s.l.) were investigated using ten molecular markers (microsatellites). The analysis of genetic sub-structuring identified at least two differentiated groups of populations inhabiting the southern and northern region of the Westerwald. We found low overall genetic diversity, but partially large genetic differences among populations. Fragmentation of populations inhabiting nearby locations (< 500 m distance in between) indicates a low dispersal capacity. Thus, conservation measures should focus on the connectivity of neighbouring populations through stepping stone ponds. Further analyses will give more precise insights concerning genetic relatedness to nearby populations in western Hesse.