Researchers used population dynamics modeling to assess the effects of size-specific and age-specific harvesting of Atlantic cod (Gadus morhua) on the eastern Scotian Shelf, Canada, and found that fishing to a depth of 80 m accounted for 72% of the observed age-related cod habitat deepening, and increasing fishing depth to 120 m accounted for 100% of the deepening; the effects declined during a moratorium on cod fishing in the area, suggesting that age-related and size-related habitat deepening observed in commercially harvested species may be a result of size-selective harvesting.
Article #18-02096: "Exploitation drives an ontogenetic-like deepening in marine fish," by Kenneth T. Frank, Brian Petrie, William C. Leggett, and Daniel G. Boyce.
MEDIA CONTACT: Kenneth T. Frank, Bedford Institute of Oceanography, Dartmouth, CANADA; tel: 902-426-3498, 902-452-3498; e-mail: <Kenneth.Frank@dfo-mpo.gc.ca>
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Journal
Proceedings of the National Academy of Sciences