A Self-Reproducing Population of Common Carp Cyprinus carpio at 59°16'N in Sweden

In this brief report, the occurrence of young-of-the-year common carp is reported, as well as older juveniles, in a golf course irrigation pond in Stockholm County, Sweden. This documents a case of natural reproduction of the regularly stocked non-native carp in Swedish waters, near the northern limit for the stocking operations. It suggests that risks for ecological impacts through the establishment of self-reproducing populations of common carp can be higher than previously assumed.