Latitudinal variations in the occurrence of some cod parasites along the west coast of Norway

Abstract

Latitudinal variations in the occurrence of four parasite species infecting cod along the west coast of Norway are described, based on data collected at four sampling locations from Øksfjord (Finnmark) in the north to Ålesund (Møre og Romsdal) in the south. The parasites are: the congeneric adult digeneans Hemiurus communis and H. levinseni, metacercariae of the digenean Prosorhynchoides borealis and plerocercoids of the cestode Diphyllobothrium phocarum. The reasons for the latitudinal variations are explained and discussed in terms of the life cycles and endemic areas of the parasites, and we suggest how they may be used as biological tags in population studies of cod and other gadoid fish in Norwegian waters.

Keywords:

• Latitudinal variations
• cod parasites
• Norway

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Acknowledgements

The CODPAR project was jointly funded by the Norwegian Research Council and Innovation Norway. We thank our partners in the project, and staff at the cod farms and the companies Fjord Marine Cod, Helgelandstorsk, Kvarøytorsk, Branco and Ultra Seafood Loppa. We are grateful to the fishermen's guild at Øksfjord and the Ålesund University College for the use of their facilities. Thanks also to Pål Arne Bjørn, Stein Eric Solevåg and Anne Stene for field coordination and facilities in Øksfjord and Ålesund, and to the anonymous reviewer for suggestions on improving the manuscript.

Notes

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark