Local anthropogenic contamination affects the fecundity and reproductive success of an Arctic amphipod

This study investigates whether adaptation to life in contaminated Arctic areas carries a cost for the populations in terms of reduced fecundity and reproductive success. The benthic amphipod, Orchomenella pinguis occurs in huge densities in both clean and contaminated sites. O. pinguis was collected at contaminated sites in an open fjord adjacent to Sisimiut, West Greenland, and at clean sites outside the fjord exposed to open waters. The broods of gravid females were analyzed for number of embryos, embryonic developmental stage and number of embryo abnormalities. Further, a sample from 3 of the sites was sexed and analyzed for intersex occurrence. The individuals collected at the most contaminated site had significantly higher fecundity (i.e. reproductive potential), but also higher frequency of embryo aberrations resulting in lower fertility (i.e. actual reproductive success) compared to clean site individuals. These results indicated a cost of living in highly contaminated environments in terms of reduced reproductive success. This study confirms the potential of the benthic amphipod O. pinguis as a bioindicator for assessments of reproductive effects of contaminants in the Arctic marine environment.