May 31, 1996 Contact: Amy Adams or Robert Irion (408) 459-2495; irion@ua.ucsc.edu

UC SANTA CRUZ GRADUATE STUDENT STUDIES A NOVEL WAY FOR MONTEREY BAY TO REGULATE ROCKFISH FISHERIES

FOR IMMEDIATE RELEASE

SANTA CRUZ, CA--Monterey Bay provides a happy home for rockfish. Reddish, canary, and cowcod rockfish live in the deep reefs, while blue, brown, and china rockfish stay closer to shore. This myriad of species attracts fishers to the bay and gourmands to the area's seafood restaurants. But rockfish numbers are slowly dwindling, and the tastiest species may nearly be fished out.

The answer to shrinking rockfish numbers may lie in small marine reserves dotting Monterey Bay and the nearby coast. Michelle Paddack, a graduate student in marine sciences at UC Santa Cruz, studies rockfish populations at three protected areas: Hopkins Marine Life Refuge, Point Lobos State Reserve, and Big Creek Marine Ecological Reserve. Paddack is discovering that these reserves, which are closed to public fishing and diving, house adult rockfish whose offspring may later replenish fished water.

"Marine reserves are used extensively by some countries," says Paddack. "They may be a better management strategy than size limits or quotas. Since most rockfish live deep and die from pressure differences when you pull them up, you can't set a size limit on them."

Paddack's work is one aspect of a long-term monitoring project coordinated by Nicole Crane, subtidal research director for the San Francisco-based Oceanic Society. Crane's goal is to establish research sites around Monterey Bay to monitor species patterns and diversity over time. "We hope to establish a database that is available for researchers looking at trends in the sanctuary," says Crane.

Reserves like the ones in Monterey Bay are currently used to manage fisheries in Australia, New Zealand, South America, and on the East Coast of the United States. They work best for animals that tend to be territorial and stay in the same area, like rockfish or lobsters, because the reserve can become a permanent home. Animals living within the reserve grow larger and have more offspring to seed the surrounding waters for fishers.

The entire California coast may benefit from a few well-placed reserves, Crane believes. Offspring from a reserve are transported by currents out to sea with other rockfish larvae. After two to three months, young fish scatter along the shore to establish new homes, but scientists do not think they return to any specific place. "Hopkins may be providing fish for Santa Cruz," says Crane.

So far, the California Department of Fish and Game has not set up reserves specifically for rockfish fishery management, but the department established four reserves in California for research and protection purposes. Paddack hopes that by studying reserves in and near Monterey Bay, she can encourage fisheries to establish more protected areas. "The current reserves are often not in prime places to preserve fish," says Paddack. Since the reserves weren't set up for fisheries management, she notes, they may not be in the most productive sites for the fisheries.

At each of the three marine reserves in her study, Paddack samples at least two established sites within the reserve and two outside. She and other divers measure the number and species of rockfish and their sizes using a see-through Plexiglas ruler. At Hopkins Marine Life Refuge, Paddack has found more fish inside than outside the reserve, and the ones inside grow larger. However, she does find more small rockfish near the edge of the preserve than farther away. Since rockfish are territorial, the researchers speculate that mature rockfish may force smaller ones outside the boundaries of the reserve. "Big beefy guys may be protecting big chunks of the reef," says Paddack.

The other two sites showed the same trend, with more fish inside than outside the reserve, but it was less noticeable than at Hopkins. "The reserves may be too small, or poaching may be too intense, or they weren't a good habitat for fish to begin with," says Paddack. "I think no one has done research on finding the best size for the reserves."

Rockfish are not only important as adults. Their young are eaten by a variety of larger animals such as lingcod, wolf eels, seals, and even adult rockfish. "Those babies are chow for so much," says Paddack. Declining rockfish numbers could affect many other fisheries in Monterey Bay by removing a major food source.

Because of their importance, rockfish were the first species sampled by the researchers, but Crane plans to expand the program next year. She is working with local agencies and scientists to decide which other organisms the reserves might affect most noticeably. Crane says she wants to study fish and other animals that are sensitive to change, long lived, and logistically easy to sample.

Crane's project is funded by the Oceanic Society, the David and Lucile Packard Foundation, and the Monterey Bay National Marine Sanctuary. Volunteers who wish to assist with the research may call the Oceanic Society at 1-800-326-7491.

Paddack's work is part of the Monterey Bay Regional Studies (MBRS) program at UCSC. Students in this program are involved in interdisciplinary studies of the Monterey Bay Area. Under the auspices of MBRS, Paddack is setting up a collaboration with sociology students interested in social aspects of marine reserves.

Editor's note: You may reach the scientists as follows: Michelle Paddack: (408) 454-0734; mpaddack@cats.ucsc.edu Nicole Crane: (408) 655-6245; ncrane@leland.stanford.edu

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