Spatial distribution of spawning sites of pikeperch [Sander lucioperca (L.)] in a highly eutrophic clay-turbid lake ? implications for management

Abstract

The spawning sites of pikeperch were mapped using artificial spawning nests in the clay-turbid Lake Tuusulanjärvi in southern Finland to protect the most important spawning areas. Altogether 272 artificial spawning nests were set before actual spawning on potential spawning grounds. The first observations of eggs were made on 26 May at a surface water temperature of 12°C. No new eggs were found after 10 June at water temperature of 16°C. The nests were removed on 18 June when the larvae had already hatched. The study demonstrated that artificial spawning nests could be used to evaluate both duration and spatial dimensions of spawning of pikeperch.