Thursday, 1 September 2011

Impacts of Fishing Low-Trophic Level Species on Marine Ecosystems


Reduced catches of small oceanic ‘forage’ fish may be needed in some areas in order to protect the larger predators that rely on these species for food. This is a finding from the first major study of the ecosystem effects of fishing forage species.

Published in the 21 July 2011 issue of Science, Beth Fulton, science leader at Australia's Commonwealth Scientific and Industrial Research Organisation, and colleagues used a range of ecosystem models to explore
the effects of fishing low trophic level species on marine ecosystems, including marine mammals and seabirds, and on other commercially important species. In five well studied ecosystems, they found that fishing these species at conventional maximum sustainable yield (MSY) levels can have large impacts on other parts of the ecosystem, particularly when they constitute a high proportion of the biomass in the ecosystem or are highly connected in the food web.

The authors conclude that halving exploitation rates would result in much lower impacts on marine ecosystems, while still achieving 80 percent of MSY.