Diet and growth of pikeperch (Stizostedion lucioperca L) in a Baltic Sea area

The diet of the freshwater fish pikeperch (Stizostedion lucioperca L.), inhabiting Himmerfjarden bay in the northern Baltic Sea proper, is dominated by prey of marine origin: crustaceans, gobies (Pomatoschistus sp.) and herring (Clupea harengus L.). At a length of 10 cm, the stomach contents consist of roughly equal proportions of fish and crustaceans. The proportion of crustaceans decreases with the size of the pikeperch and it is replaced by fish. The size of the prey fish increases with the size of the pikeperch, and corresponds, on average, to 30% of the length of the pikeperch (analysed fish 10-50 cm). Although pikeperch is a freshwater species, its growth in the brackish Baltic Sea is at least as good as in lakes at the same latitude. (C) 1997 Elsevier Science B.V.