"Reserves should set aside at least 30 percent of the habitat of a given species to have any serious assurance of long-term profitability, as well as to guard against risk of extinction," says Stanford Professor Joan Roughgarden, an ecologist who will present her model for sustainability of marine resources Feb. 15 during the annual meeting of the American Association for the Advancement of Science (AAAS) in Boston. Roughgarden, who will present her research at a symposium titled "Community-Based Marine Resource Management: Incentives for Sustainable Management and Conservation," is a pioneer in applying economic theories to ecological problems. The "30 percent set-aside rule" is the result of a new model that computes the best strategy that small-scale sustainable fisheries can employ to optimize profit and social welfare. To determine the best strategy for managing fisheries, Roughgarden's model includes - for the first time ever - the risk of extinction.
"It is a fundamental thing to take risk of extinction into account, which until now hasn't been done in economic theories," Roughgarden says. In her role as a scientific adviser for the establishment of the Channel Islands National Marine Sanctuary near Santa Barbara, Calif., Roughgarden applied her model to define the size of "no-fishing" zones. In these protected areas, fish stocks can recuperate and refill harvest zones through spillover.
For a sustainable harvest aimed at maximizing long-term welfare of the fishery, at least one-third of the fish habitat has to be protected, Roughgarden's model demonstrates. Smaller habitat size will not ensure the survival of marine resources or fisheries, which may eventually lead to extinction of the fishing grounds. "We don't want to convey a false sense of security to people who valuably try to establish smaller reserves, only to see these efforts lost when everything collapses," Roughgarden says. In 2000, the United Nations' Food and Agriculture Organization warned that about one-quarter of the world's marine resources were either overexploited or already depleted. About half of the marine fishing grounds were classified as "fully exploited," meaning that increased fish production from these regions is unattainable. Therefore, only about a quarter of the world's fishing grounds can boost fish production to satisfy the growing global demand for fish. For sustainable fisheries and successful establishment of marine protection programs, the immediate and long-term economical benefits for the fisheries have to be secured through incentives. They should encourage and reward fisheries in their effort to sustainably manage marine resources.
The fishery industry has more than doubled in the last 30 years. Ninety-five percent of the world's fishers are from developing countries and work in traditional artisan fisheries whose combined catches amount to about 50 percent of the 125 million metric tons of fish harvested worldwide each year. For that reason, implementation of "no-fishing" zones has met with tremendous resistance among people economically dependent on fishing. Co-management of marine resources by governments, private fisheries and communities only recently has been recognized as an effective way for sustainable management programs to gain acceptance.
"The focus must be on understanding the connectivity between people and the ocean," says Assistant Professor Fiorenza Micheli of Stanford's Hopkins Marine Station in Pacific Grove, Calif. "Often there have been a tradition and a culture of using marine resources with a conservation perspective in mind." Together with biologist Rafe Sagarin, a postdoctoral scholar at Hopkins, Micheli initiated and organized the AAAS symposium.
Partnerships between local communities and scientists in the central islands of the Philippines, for example, resulted in implementation of marine reserves as a tool to manage overexploited fisheries. The establishment of "no-fishing" zones has increased catches in adjacent fishing grounds. "This is a good example where political will to support conservation was reinforced by ecologists that showed that there was an effect," Micheli says.
A more consumer-driven approach to conservation is the certification process initiated by the Marine Stewardship Council (MSC) that Julia Novy-Hildesley from the World Wildlife Fund (WWF) will present at the AAAS symposium. This program promotes sustainability of fisheries through rewarding local communities for sound management practices. The MSC has established in collaboration with Unilever - one of the world largest makers of fish products - and the WWF a label that tells consumers that fish products came from fisheries that have been certified as sustainable. "The idea behind certification of marine fisheries is that you can use the power of the market to force and encourage sustainable catching practices," Micheli says.
Other speakers at the symposium will include anthropologist Richard Stoffle, University of Arizona, and ecologist James Acheson, University of Maine. Three successful examples of sustainably managed community-based fisheries in Chile, Mexico and the Philippines will be presented by Miriam Fernandez, Pontificia Universidad Catolica de Chile; Mario Ramade Villanueva, Federacion Regional de Sociedades Cooperativas de Mexico; and Angel C. Alcala, Silliman University-Philippines.
-By Christian Heuss-
COMMENT: Joan Roughgarden, Biological Sciences (650) 723-3648; firstname.lastname@example.org Fiorenza Micheli, Hopkins Marine Station (831) 655-6250; email@example.com Rafe Sagarin, Hopkins Marine Station (831) 655-6251; firstname.lastname@example.org
EDITORS: This release was written by science writing intern Christian Heuss.