WORLD'S FISH EXPERTS WILL PLAN TO RE-STOCK THE SEA

BALTIMORE, Md.-Fifty to 60 researchers, including many of world's top fisheries and aquaculture scientistswill meet March 19-20 in Baltimore to address an urgent food question for the near future:

Can we hatch, culture and release enough baby fish, crabs, shrimp, oysters and other seafood species to keep the oceans stocked?

In the 1990's, the United Nations and other world authorities reported serious declines, even the collapse of many commercial fish populations and, for the first time, a zero increase in world fish harvests.

The meeting, "Assessing the Promise of Replenishing Marine Fisheries," will be held at the University of Maryland Biotechnology Institute's (UMBI).

Center of Marine Biotechnology (COMB), beginning at 8 a.m. on the 19th. It will include presentations on a variety of stock enhancement programs in North America, Japan and Europe, followed by roundtable discussions on how best to apply science to enhance diminishing seafood stocks. For agenda, click on: www.umbi.umd.edu/~comb/programs/aquaculture/workshop.html.

There is an urgent need for scientists to explore successes and failures in the field, to identify future research needs and to evaluate the potential impact of releases of hatchery-produced juveniles in replenishing marine and estuarine fisheries, according to COMB Director Yonathan Zohar, organizer of the meeting.

There seems to be no stopping the overexploiting of the oceans, considering world growth of human population, he adds. "With marine fish populations continuously declining, the world has reached an alarming situation often referred to as 'the tragedy of the oceans'," says Zohar.

Decline in harvests coincides, however, with renewed scientific optimism that stock enhancements can be managed in ecologically sound and commercially profitable ways. According to many of the invited scientists, "uncertainties" in stock enhancement developed during the previous century when experiments were rushed into use without science-proven technology in hatcheries, fish genetics and ecological assessment of the fish health and habitats.

Some 30 to 35 researchers will evaluate and discuss successes and failures in the field and their "pros" and "cons," adds Zohar. "With recent advances, mistakes of the past can be now avoided and impediments overcome," he says. "Tools of modern biology can be efficiently used to determine the fate of the released juveniles and evaluate their recruitment to the fisheries stocks. New and responsible approaches to stock enhancement may be developed through rigorous and multidisciplinary aquaculture, fisheries and genetics research." A consensus, "white paper" report of the meeting will also be published, he says.

Here are just a few of the projects to be discussed and evaluated:

Fish-farming aspects of hatching and raising juvenile fin and shellfish:

• Female Maryland blue crabs, exposed to 14-hour days in captivity at COMB, began to ovulate and produce broods five months earlier than in the wild. First hatchings of the crab studies, in cooperation with COMB's partners in Maryland, Virginia and North Carolina, occurred in mid-January 2001. Brood production and hatching continued all year. The study produced juvenile, 20-mm crabs in only two months. They were raised to adults. Females then reached puberty and mated with captive male offspring as young as 9-months old.
• In studies of red snapper fish, scientists have cultured, released and recovered small numbers off the coasts of Mississippi and Florida. From the snapper work and others, the U.S. Gulf of Mexico Marine Stock Enhancement Program is developing a working model for any stock enhancement. The keys are natural spawning of captive brood stock and larval rearing. DNA techniques are used to identify genetic populations and to stop introduction of diseases inadvertently upon release.

Technologies of hatcheries, fish genetics, and monitoring released juveniles:

• Sea ranching of Atlantic salmon, Atlantic cod, Artic char and European lobster was a scientific success in the 1990's by the Institute of Marine Research in Norway. Although raising and releasing large numbers of the four species has not yet shown economic promise, there is renewed interest in stock enhancing lobsters and scallops.
  
• In Japan, a quarter million juvenile swimming crabs were released by the Osaka Prefectural Fisheries Experiment Station. Income from fisherman catching the crabs was sufficient to justify the cost of the study, say Osaka scientists.
  
• More than 400,000 White Sea bass have been cultured, tagged and released since 1986 in Southern California waters by the Hubbs-SeaWorld Research Institute in San Diego. The institute is helping rebuild fish stocks that support as much as $450 million in fishing industries.
  
• Using coded wire tags on juvenile crabs, Japanese scientists with the Shizuoka provincial government's Department of Agriculture, Forestry and Fisheries detected and identified tagged crabs in the semi-enclosed Lake Hamana.

Ecology and well being of each species to be released:

• The question of restoring sturgeons into the Chesapeake Bay will depend on using hatchery-produced juveniles, say researchers at the Chesapeake Biological Laboratories at Solomon's, Maryland. They are determining if Bay waters still have sufficient habitats for the bottom dwelling sturgeons, which were a common species in the early 20th century but have vanished.
  
• The introduction of vigorous Louisiana oysters into a Chesapeake Bay river is being tracked with DNA techniques by a team led by the University of Delaware. Maryland officials planted oyster spat (babies) into the river five years ago. The experiment is part of efforts to maintain healthy oysters for restocking.

COMB is an internationally recognized research laboratory devoted to the application of molecular biology and molecular genetics to marine organisms. It is located at 701 East Pratt Street, Baltimore, MD 21202. Telephone: 410.234.8800.

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The University of Maryland Biotechnology Institute was mandated by the state of Maryland legislature in 1985 as "a new paradigm of state economic development in biotech-related sciences." Five UMBI research and education centers are dedicated to leading and partnering to advance biotechnology. The centers are Center for Advanced Research in Biotechnology in Rockville; Center for Agricultural Biotechnology in College Park; and COMB, the Medical Biotechnology Center, and the Institute of Human Virology, all in Baltimore.