The Future of Salmonid Communities in Fennoscandian Lakes

In trying to make predictions for the future of the Fennoscandian lakes it is difficult to disregard the obvious threat of a common protein deficiency in the world population. At the moment, however, there is a trend in the fishery away from a commercial and subsistence gillnet fishery towards a use...

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Bibliographic Details
Published in:Journal of the Fisheries Research Board of Canada
Main Authors: Grimås, Ulf, Nilsson, Nils-Arvid, Toivonen, Jorma, Wendt, Curt
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1972
Subjects:
Online Access:http://dx.doi.org/10.1139/f72-136
http://www.nrcresearchpress.com/doi/pdf/10.1139/f72-136
Description
Summary:In trying to make predictions for the future of the Fennoscandian lakes it is difficult to disregard the obvious threat of a common protein deficiency in the world population. At the moment, however, there is a trend in the fishery away from a commercial and subsistence gillnet fishery towards a use of the lakes for recreational purposes. Eutrophication induced by man is proceeding everywhere, although governmental authorities are aware of this threat. In some large lakes the process may have reached an optimum where it is still favouring production of relatively large yields of some important species of fish. Exploitation of some species, for example salmonids and sander, is in some cases overly intensive, but is not yet regarded as a serious problem. Introductions of "exotic" species have had little influence on native stocks. The release of hatchery-reared landlocked salmon, rainbow trout, and lake trout will hopefully raise the value of the fishery in some lakes in the future. Pollution by toxic substances such as mercury, DDT, and PCB, and the fall-out of SO 2 from the atmosphere, are at present the most serious threats to the fishery.