p. 271 - 277 RESEARCH CONCERNING THE EXPLOITATION OF PIKE-PERCH (STIZOSTEIDON LUCIOPERCA L.) POPULATION IN THE RAZELM LAKE M. Staras Danube Delta Research and Projects Institute Tulcea Abstract In 1961-1988, total fish yield of the Razelm Lake increased while the pike-perch yield was steadfast up to 1986, than it decreased. The eutrophication and intensively exploitation of pike-perch population determine important changes of population structure. The most catched pike-perch specimens do not reach sexual maturation. Analysing the dynamic of biomass and yield per recruit in accordance with the length of first capture and fishing intensity, the necessity of mesh size resulted.