Competition among fishermen and fish causes the collapse of Barents Sea capelin
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Updated: Aug 11, 2026

Methods for Image-based Surveys of Benthic Macroinvertebrates and Their Habitat Exemplified by the Drop Camera Survey for the Atlantic Sea Scallop
Published on: July 2, 2018
Dag Ø Hjermann1, Geir Ottersen, Nils Chr Stenseth
1Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, Post Office Box 1050 Blindern, N-0316 Oslo, Norway.
Abstract:
The vast majority of the world's fisheries are typically managed within a single-species perspective, ignoring the dynamic feedback mechanisms generated by the ecological web of which they are a part. Here we show that the dynamics of the Barents Sea capelin (Mallotus villosus), the world's largest stock of this species, is strongly influenced by both within-system ecological feedback mechanisms and the impact of harvesting. Both overexploitation and predation by herring (Clupea harengus) can cause the population to collapse, whereas predation by cod (Gadus morhua) is demonstrated a delay in the stock's recovery after a collapse. Such collapses, which have occurred twice in 20 years, affect the entire Barents Sea ecosystem, a region that for ages has provided food for all of Europe.
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