Marine reserves can be effective tool for managing fisheries

Washington, November 10 (ANI): Biologists at the University of California, Santa Cruz have said that studies conducted in California and elsewhere provide support for the use of marine reserves as a tool for managing fisheries and protecting marine habitats.

A recent study in the Gulf of California, for example, confirmed the validity of a key concept behind marine reserves - the idea that offspring produced in a protected area can replenish the stocks of harvested species outside the reserve.

"It seems really obvious, but it had never been tested," said Peter Raimondi, professor and chair of ecology and evolutionary biology at UCSC and coauthor of a paper describing the findings.

"We created a model to predict the dispersal of larvae outside the reserves, and the results were completely consistent with our predictions," he said.

Raimondi emphasized that resource managers have a wide range of tools at their disposal and must take into account both biological and social factors in choosing the best approach.

Raimondi and Mark Carr, also a professor of ecology and evolutionary biology at UCSC, are engaged in an intensive monitoring program to track the effects of the reserves that have already been established.

"We are monitoring those areas at unprecedented levels. It's a comprehensive effort to characterize the populations and the ecosystems so that we can compare the responses to different types of protection," Carr said.

"Monitoring studies around the globe systematically show positive responses within protected areas. We want to really identify what aspects of reserve design are important in influencing those benefits," he added.

According to Carr, it will take a few more years of monitoring to see the effects of the Central Coast reserves.

In the Channel Islands, however, where reserves were established in 2003, surveys have yielded the kinds of results scientists expect to see in protected areas.

For example, fish species targeted by fishermen tend to be bigger and more plentiful within the reserves.

This effect is important, because studies have shown that larger, older females are much more important than younger fish in maintaining healthy populations of species such as West Coast rockfish.

"When you have a protected population, you not only get spillover effects when fish swim out of the reserve and get caught, you also have major effects on larval production," Carr said.

"The bigger, older fish in the reserve produce a lot of larvae that replenish the fished populations outside," he added. (ANI)