The main objectives of this study were to examine the effects of coastal eutrophication on fi sh communities, and on local recreational fi shery and commercial pikeperch fi shery on the northern coast of the Gulf of Finland. The study focused on freshwater species, as they live their entire life cycle in the most eutrophied areas, ., the archipelago and inner bays. Freshwater species are important for the very popular recreational fi shery, forming the bulk of the annual total catch. Certain freshwater species, such as pikeperch, are also important for the small-scale commercial fi shery. The main study methods used were gill net surveys, a. | The Effects of Recent Eutrophication on Freshwater Fish Communities and Fishery on the Northern Coast of the Gulf of Finland Baltic Sea Antti Lappalainen Department of Limnology and Environmental Protection University of Helsinki Finland and Finnish Game and Fisheries Research Institute Academic Dissertation To be presented with the permission of the Faculty of Agriculture and Forestry of the University of Helsinki for public criticism in Auditorium 1041 Biocentre Viikinkaari 5 Viikki Helsinki on 20th September 2002 at 12 o clock noon. Helsinki 2002 Author s address Finnish Game and Fisheries Research Institute . Box 6 Pukiumaenaukio 4 FIN-00721 Helsinki Finland E-mail Supervisor Martti Rask . Docent Finnish Game and Fisheries Research Institute Evo Fisheries Research Station FIN-16970 Evo Finland Reviewers Erik Bonsdorff . Professor Environmental and Marine Biology Abo Akademi University Akademigatan 1 FIN-20500 Abo Finland Henn Ojaveer . Estonian Marine Institute Viljandi Road 18 b 11216 Tallinn Estonia Opponent Johanna Mattila Docent Huso Biological Station Environmental and Marine Biology Abo Akademi University Akademigatan 1 FIN-20500 Abo Finland Copyrights Article I 2000 Wiley-VCH Verlag Berlin GmbH Article II and V 2000 and 2002 Federal Research Centre for Fisheries Hamburg Article III 2001 Finnish Zoological and Botanical Publishing Board Article IV 2000 Blackwell Science Ltd ISBN 951-776-379-4 Layout Graphics EDIMAC Printer Vammalan Kirjapaino Oy Vammala Finland Contents Original articles and author s contribution .5 Marine eutrophication and the Baltic Eutrophication of the Gulf of Changes in fish communities in the Baltic Marine species .8 Migratory Freshwater species .9 Eutrophication and fish communities in lakes general Fishery in the northern Gulf of Finland . 10 Aims and research strategies . 10 Material and methods. 11 Study area. 11 .
