Reserves good for fisheries

Hawai‘i has 10 marine life conservation areas on four islands, which a newly released study suggests are a great idea — not only for the fish.

While it may seem counterintuitive, it appears the very fishing interests that are excluded from marine reserves are the ones that benefit the most, because fishing in neighboring areas is vastly improved.

"All around the world there are different experiences, but the basic message is the same: Marine reserves work, and they work fast," said Jane Lubchenco, Oregon State University zoology professor and a past president of the American Association for the Advancement of Science, speaking for 150 marine scientists from around the world. They performed a three-year study through the National Center for Ecological Analysis and Synthesis at the University of California, Santa Barbara.

Not all of Hawai‘i’s reserves meet the requirements developed by the study, since most allow some level of fishing. The scientists concluded that fully protected reserves are the most valuable.

"The results are startling and consistent," said UCSB marine biology professor Robert Warner. Even after just one or two years of complete protection, researchers found fish numbers nearly doubled, their average size up a third and the diversity of species higher by one-fourth. The overall biomass in reserves was almost tripled.

The benefit to those who consume marine products is in the "spillover" effect — fish and shellfish moving out into neighboring waters, and larvae from the dense areas washing into nearby regions.

The study indicated that New Zealand anglers who aggressively opposed sanctuaries were finding snapper populations increased as much as 40-fold. They since have become big supporters of the idea. In Maine, scallop fishing boats were working right along the edges of the reserves because there were so many more scallops there.

"You want to design reserves so that they have a spillover effect in helping replenish the ocean beyond the protected area. Well-designed networks are the key," said Harvard University evolutionary biologist Steve Palumbi.

The scientists have designed a computerized tool that can help fishery managers design reserves. (See www.seaweb.org/AAAS.)

Hawai‘i’s reserves are on O‘ahu, Hawai‘i, Lana‘i and Maui, with none on Moloka‘i, Kaua‘i or Ni‘ihau. Only two of the 10 reserves are fully protected, according to a staffer at the state Division of Aquatic Resources. Palumbi does not argue against reserves that allow some "extraction" activities such as limu collecting, fishing or coral diving, but he said the subclass of fully protected sanctuaries are "a powerful tool for marine conservation and management."

Jan TenBruggencate is The Advertiser’s Kaua‘i bureau chief, and its science and environment writer. You can call him at (808) 245-3074 or send e-mail to jant@honoluluadvertiser.com.

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