Growth of Bream,Abramis brama L., in Two Outside Basins of Different Trophic State of Lake Balaton

Age-composition, size-distribution, length/weight relationships and growth both in length and weight of bream stocks were studied on fishes collected in NE and SW basins of Lake Balaton during 1982/83. Stocks consisting of 10 to 12 age-groups were observed at the two lake areas. The linear growth and weight-gain in the SW-basin were annually faster than in the NE-basin, however, the growth of bream in Lake Balaton was slow as compared to that observed 10 years ago. Parallel with progressive eutrophication, the density of bream stocks increased by some 5–10 % especially at hypertrophic lake areas (SW) and consequently their growth was transformed to densitydependent. In the appearance of strong year-classes some cyclicism could be observed especially in the SW-basin.