Fish and Fisheries in the Lakes of Northeastern Poland

Abstract

In this article, we present the most comprehensive and up-to-date assessment of freshwater fish diversity in the lakes of northeastern Poland, and we use these data to characterize patterns of fish diversity and characterize the fisheries. The northeastern region of Poland is home to the country’s largest complex of lakes, with the deepest (Hańcza) and largest (Śniardwy) lakes in Poland. To date, 43 species belonging to 15 families are confirmed to occur in the lakes of northeastern Poland. Among these, the cyprinids are dominant. Most of the fish species noted in this region occur commonly in Poland; however, as many as 27% of the species are classified as highly endangered and are under species conservation. A substantial part of the fish fauna of northeastern Polish lakes is comprised of alien species, of which nine are noted in the region. For centuries, this region was the center of lake fisheries in the southern Baltic Sea basin. Currently, 70 different types of enterprises conduct fisheries in the region, but, in the face of progressing lake eutrophication, changes in catch structure are occurring, and the fisheries yield is decreasing. Common bream (Abramis brama), pike (Esox lucius), roach (Rutilus rutilus), and eel (Anguilla anguilla) are commercially the most important fish species in commercial catches in the lakes of northeastern Poland.