EN
Fisheries structure is associated closely with habitat conditions. Even small changes in hydrochemical conditions can affect the composition of ichthyofauna, and, therefore, catch structure, which is notable even after just a few years. In contrast, drastic changes in habitat conditions can affect ichthyofauna structure through the high mortality of economically valuable fish. The trophic status of Lake Miedwie waters has decreased in recent years, while catches of predators have increased. Cyprinid catches result from the high productivity of the lake in the 1980s and 1990s and the high tolerance these fish have for environmental conditions.