Species-genetic diversity correlation in a metacommunity of urban pond invertebrates

Understanding patterns of species-genetic diversity correlations (SGDC) is important for conservation purposes because it allows us to infer whether conservation of species diversity (SD) influences conservation of genetic diversity (GD) and the other way around. Here, we studied SGDCs using aquatic macrofauna in a set of 31 urban ponds in the metropolitan area of Stockholm, Sweden. We also estimated how land use and pond environmental factors affect SD and GD. SD was estimated as species richness. GD was estimated in four focal species that differed in their dispersal abilities: Asellus aquaticus (Isopoda), Haliplus ruficollis (Coleoptera), Planorbis planorbis (Gastropoda), Rana temporaria (Amphibia), using double digest restriction associated DNA (ddRAD) sequencing data. There were no significant SGDCs for any of the species. Similarly, GD was not related to land use or pond environment. However, SD had a significant positive correlation with total invertebrate abundance and pond area. Given the absence of significant SGDCs in our study, and the mixed positive and negative patterns found in previous studies reporting SGDCs, we suggest that simultaneously preserving species and genetic diversity in urban areas will prove challenging.