Effects of kelp harvesting on fish and crabs, Flatanger 2014

The Institute of Marine Research studied effects of kelp (Laminaria hyperborea) harvesting on near shore fish and crab abundance in Flatanger, Nord-Trøndelag in August 2014. Recordings were made using fixed underwater camera systems and traditional fish and crab catching gear in kelp harvested areas and in reference kelp beds. The methods sample different species and sizes of fish, and supplement each other. There was a significant reduction of small cod and an increased amount of wrasse caught in wrasse traps on the harvested field two years after kelp harvesting, compared to pre-harvesting catches, indicating opposite effects of kelp harvesting on these groups of fish. However, the study suffers from a relatively low number of sampling units for the preharvesting recordings, and knowledge on the effects of kelp harvesting on fish and crab abundances should be supplemented by future studie