Hatchery Project Sending White Bass to the Open Sea

They are only two to three inches long and their numbers are hardly significant, but someday they could prove to have a great impact on fish population in the waters off San Diego.

When 2,000 young white sea bass are released into Mission Bay this morning, it will be the first time in the nation that marine fish raised in a hatchery will be introduced to the wild to replenish the stock for commercial and recreational fishing.

“It’s more symbolic than anything else,” said Don Kent, assistant director of operations at the Hubbs Marine Research Institute at Sea World, where the bass were hatched three months ago. “Right now, we’re at a point where we’re going to release some fish and see what happens to them.”

Kent and his fellow researchers hope the initial results are encouraging enough to expand the program to include more fish and more species. Marine biologists at Occidental College in Los Angeles are involved in similar work with halibut, and Kent looks forward to being able to hatch large numbers of kelp bass and yellowtail as well.

“The white sea bass is just a target species we’ve selected right now,” Kent said. “What we’re hoping to do is demonstrate the technology and the applicability of the technology.”

In addition to portending further advances in the field, today’s release at Sea World marks the culmination of a four-year effort by scientists and conservationists to successfully raise marine fish in hatcheries.

Kent said that, although a typical female white sea bass lays about 100,000 eggs at a time, in the wild the vast majority of these succumb to predators or other natural population controls, meaning that only one or two fish are able to spawn.

This low fecundity, coupled with intensive commercial fishing and destruction of habitat, has caused populations of species such as the white sea bass to shrink alarmingly, Kent said. In the early 1950s, San Diego fisherman caught more than 70,000 white sea bass a year; now the annual catch numbers less than 1,000, he said.

In the project’s first four years, Kent and other researchers have overcome most problems involved in trying to raise the fish in the controlled environment of the hatchery, such as setting the optimum water temperature and predicting when the fish will spawn. Also working on the project are researchers at Occidental, the Scripps Institution of Oceanography, San Diego State University and UC Davis.

Under ideal circumstances, Kent said, as many as 10,000 eggs may be viable and researchers can nurture as many as 2,000 fish to spawning age. The main limitation on marine fish hatcheries is lack of space, he said.

“What we need to do is to expand our facilities to handle more juvenile fish,” Kent said. “We’d like to be releasing 100,000 fish a year.”

Such mass releases could greatly increase the stock of ocean fish available for both sport anglers and commercial fishermen, he said. However, Carl Nettleton, president of the National Coalition for Marine Conservation, Pacific Region--the organization that spearheaded the sea bass project--said replenishment is not the program’s primary goal.

“Our organization feels that if population enhancement works, it will be a bonus,” Nettleton said. “We’re learning about the fish, learning how they grow, where they grow, to try to find out if there are environmental problems that stop the fish from getting to a certain life stage. We’re trying to raise the fish by hand and try to get them past that point.”

And, as Nettleton will attest, the obstacles encountered along the sea bass project’s four-year journey were as much bureaucratic as biological. In 1982, the National Marine Fisheries Service denied the coalition’s request for funding, forcing the group to pay for much of the project with fund-raisers such as its annual “Fish for the Future” barbecues.

In 1984, a bill authored by Assemblyman Larry Stirling (R-San Diego) brought the program $500,000 a year, raised from a stamp tax of $1 a year on ocean fishermen and $10 a year on commercial fishermen and party boat operators. If the program progresses as researchers hope, Kent said, the anglers will have received their money’s worth.

“I think most fishermen are more than willing to pay $1 a year if it’s going to something that will give them better fishing,” he said. “We’re at a real (research and development) level right now, and if we can demonstrate that this is viable, I don’t think the fishermen will have any trouble with it at all.”