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Research article - Peer-reviewed, 2019

The necessity of a holistic approach when managing marine mammal-fisheries interactions: Environment and fisheries impact are stronger than seal predation

Costalago, David; Bauer, Barbara; Tomczak, Maciej T.; Lundstrom, Karl; Winder, Monika


Seal populations are recovering in many regions around the world and, consequently, they are increasingly interacting with fisheries. We used an Ecopath with Ecosim model for the offshore Central Baltic Sea to investigate the interactions between the changes in fish stocks and grey seal (Halichoerus grypus) population under different fishing and environmental scenarios for the twenty-first century. The assumed climate, eutrophication and cod (Gadus morhua) fisheries scenarios modified seal predation impacts on fish. Fish biomass and catches are more affected by fishing mortality and the environment than by seal predation. Our results highlight that the impacts of the increasing seal population on lower trophic levels are complex; thus, we emphasize the need to consider a range of possible ecosystem contexts when evaluating potential impacts of top predators. Finally, we suggest that an increasing seal population is not likely to hinder the preservation of the main Baltic fish stocks.


Atlantic cod; Atlantic herring; EwE; Fisheries management; Marine mammals; Sprat

Published in

AMBIO: A Journal of the Human Environment
2019, volume: 48, number: 6, pages: 552-564
Publisher: SPRINGER

Authors' information

Costalago, David
University of British Columbia
Bauer, Barbara
Stockholm University
Tomczak, Maciej T.
Stockholm University
Swedish University of Agricultural Sciences, Department of Aquatic Resources
Winder, Monika
Stockholm University

Sustainable Development Goals

SDG14 Life below water

UKÄ Subject classification

Fish and Aquacultural Science

Publication Identifiers


URI (permanent link to this page)