Movements of pikeperch (Sander lucioperca), roach (Rutilus rutilus) and bream (Abramis brama) in a boreal lake, Lake Vesijärvi, Finland

Abstract

Movements of common fish species in large lakes that are inadequately known is challenging for fisheries management. Pikeperch (Sander lucioperca) (n = 478; mean length = 42.1 cm; SD = 7.0), bream (Abramis brama) (n = 775; mean length = 31.1 cm; SD = 5.3) and roach (Rutilus rutilus) (n = 939; mean length = 21.4 cm; SD = 2.0) were marked with individual T-anchor tags to investigate movements in Lake Vesijärvi, a large lake situated in southern Finland consisting of several basins and managing by multiple entities. All species moved between basins, but only rarely moved outside tagging areas. The recapture rate of pikeperch was higher than roach and bream. Tagged fish consistently crossed municipality borders and water ownership units, thereby forming shared stocks, which underlined the importance of cooperation in lake restoration and a need to unite fragmented water ownership. Management of fisheries for cyprinid fishes could be more efficient if fishing targeted the most suitable areas without considering restrictions due to fragmented water ownership. Tagging data provided information on which parts of a large lake should be subjected to uniform pikeperch fisheries management. The importance of other species catch varied between different parts of the lake, thereby requiring different fishing regulations. Tagging data on common fish species provided valuable information on fish movements to support spatially explicit fisheries management.