Whether fishing bans can boost catches in nearby coastal waters is controversial. Now, new findings from an international team of marine scientists could help calm the waters. By measuring commercial catches and the number of trophy fish caught around reserves in the Caribbean and off Florida, the researchers determined that reserves do benefit adjacent fish stocks.
Scientists have already shown that closing swaths of the sea to human activity can produce sizable ecological benefits within reserves, from more diverse sea life to bigger schools of fish. But it's been difficult to determine whether establishing reserves also helps fish in neighboring waters. Such studies are challenging to conduct because researchers must find areas where they can compare catches before and after a reserve was established, and monitor all the relevant variables, such as the number of hours spent fishing and ocean conditions.
To measure the spillover benefits of reserves, Callum Roberts, a biologist at the University of York, U.K., and his colleagues focused on a 5-year-old network of reserves off the Caribbean island of St. Lucia and an area off NASA's Cape Canaveral rocket-launching site in Florida that had been closed for nearly 40 years. As the researchers report in the 30 November issue of Science, the reserves in St. Lucia increased catches in nearby areas by up to 90%, compared to pre-reserve numbers. Off Florida, they found that sport anglers fishing around a 40-square-kilometer area closed in 1962 have landed a disproportionate number of world- and state-record fish. Although the studied reserves were small, Roberts says the findings--when combined with sketchier data from bigger closures--make a compelling argument in favor of reserves.
One researcher, however, cautions that reserves are just one tool available to fisheries managers. "The question is, 'What role should [reserves] play in the mix of regulatory options?' " says Ray Hilborn, a fisheries biologist at the University of Washington, Seattle. Hilborn argues that less severe moves--from closed seasons to size limits--could produce equally significant fisheries improvements.
Meanwhile, some influential fishing groups and politicians are fighting reserves in U.S. waters. In August, the American Sportfishing Association and other groups convinced Senators John Breaux (D-LA) and Kay Bailey Hutchison (R-TX) to introduce the Freedom to Fish Act (S. 1314), which would require government planners to make reserves as small as possible.