Acta Univ Latv (2003) 662: 33–44

The structure and dynamics of fish communities in the Latvian coastal zone (Pape - Pērkone), Baltic Sea

Abstract

The fish biodiversity in the Baltic Sea coastal area was analysed in 1998 - 2002. Different ecological groups – marine, diadromous and freshwater – were captured in survey gillnets and beach seine catches. The coastal fish communities revealed a strong seasonal variation. The water temperature increase early in the spring caused migration of juveniles and adult marine fishes from depths to the nursery, spawning and feeding grounds located in the coastal waters. In summer mostly diadromous and freshwater fi sh species migrated from the adjacent freshwater basins to the sea coastal feeding grounds. In 1998-2002 fi sh communities comprised representatives of various ecological types. The available information from the monitoring combined with the fisheries data could facilitate an ecologically-focused management of the coastal zone ecosystem.