Spring 2014 Vol. 13 Number 2
Helping Depleted Fisheries Recover
Fishing provides a source of food and a livelihood for millions of people in the United States. In 2011, for example, U.S. commercial fishermen brought in 4.5 million tons of fish and shellfish, much of which ended up on plates in restaurants and homes across America. In some places, however, overzealous pursuit of these lucrative catches has depleted fish populations. Of the U.S. fisheries that have been assessed, about 20 percent are overfished, according to estimates by the National Oceanic and Atmospheric Administration.
When a fish population drops to a level considered overfished, federal law requires that fishery managers implement a "rebuilding" plan to help the species recover, usually within a 10-year time frame. These plans restrict fishing, which can have a serious economic impact on certain communities. Concern about such consequences has led to heavy scrutiny of the plans and their effectiveness.
The National Research Council took a look at federal rebuilding plans and, in general, found them successful at reducing pressure on many overfished populations and increasing fish numbers. But outcomes have been mixed; fishing pressure is still too high in some places, and other populations have not rebounded as quickly as projected despite fishing restrictions.
Part of the reason why some fisheries don't recover according to plan is that it's difficult to make the complex ecosystems in which fish live follow a strict timetable. Fishing limits are part of the solution, but fishing is only one of the factors that affect population levels; environmental factors also influence whether populations recover and the rate at which they do.
Currently, when fish populations do not rebound as expected, fishery managers respond by controlling what they can -- fishing levels -- even though other factors may be stalling the recovery. They impose even stricter fishing limits in an effort to meet the federal deadline, which leads to more severe economic effects for fishing communities. If instead managers could implement recovery plans to keep fishing at a reduced but consistent level until the fish populations recover, there would be fewer harmful economic impacts because the fisheries wouldn't be subject to major, unanticipated dips in fishing limits.
Fishery managers could also take action earlier, imposing gradual limits when fish populations start to drop rather than waiting until they are overfished. Then they could avoid rebuilding plans -- and the strict fishing limits that come with them -- altogether.
-- Sara Frueh
The study committee was co-chaired by Ana Parma, research scientist, CONICET (Council for Science and Technology of Argentina), Buenos Aires, and Patrick Sullivan, associate professor of quantitative population and community dynamics, department of natural resources, Cornell University, Ithaca, N.Y. The study was funded by the National Oceanic and Atmospheric Administration.