Scientists and fisheries officials are cautiously optimistic that sometime soon - perhaps as early as June - they will begin an ambitious project to return the Chesapeake's largest and longest-lived native fish, the Atlantic sturgeon, to the Bay.

Sturgeon were once one of the Bay's most valuable fish, but scientists believe the Chesapeake's native spawning stock has been wiped out. Unless something is done to "jump start" the species here, they say, it could take centuries for sturgeon from other coastal areas to colonize the Bay.

"I'm not a great advocate of stocking in the estuarine and marine environment normally, but in this case, I don't think we have much choice if we want to get the beast back," said John Musick, a sturgeon expert at the Virginia Institute of Marine Science.

At a recent meeting, scientists and state and federal fisheries managers concluded that the time is right for a reintroduction. The U.S. Fish and Wildlife Service has 7,000, year-old sturgeon available for stocking, and the Maryland Department of Natural Resources is eager to put them in the Nanticoke River.

"I'm ready to go," said Ben Florence, program director for aquaculture and hatcheries with the DNR. "We can either stock these animals now, or we can wait 150 or 200 years for the only self-sustaining population to expand and repopulate the Chesapeake Bay, and that's the Hudson River stock. Have it now, or have it a couple hundred years from now. Suit yourself."

Musick said he was interested in finding support for an experimental stocking program in Virginia's Pamunkey River, as well.

The 7,000 fish are available as a result of experiments last year at the USF&WS Northeast Fishery Center in Lamar, Pa., which has been developing sturgeon hatchery rearing techniques with eggs and sperm taken from Hudson River fish. Unless the fish are stocked soon, officials fear they will become too "domesticated" to survive in the wild.

More hatchery fish may be available later this year, and a full-scale stocking program may eventually involve the release of 50,000 fish annually.

Before the fish can be stocked, the project must pass one final hurdle - the National Marine Fisheries Service has to determine that the project will not pose a threat to the endangered shortnose sturgeon. NMFS has 60 days to make that decision after it receives a plan for the Bay stocking effort. That plan was being finalized at the end of April.

Laurie Allen Silva, of the NMFS protected species section in Gloucester, Mass., said no decision could be made until the details of the plan were reviewed, but it was unlikely an Atlantic sturgeon reintroduction would pose a major threat to shortnose sturgeon.

"The two species aren't occupying exactly the same niche," she said. "The Atlantic sturgeon are in more saline waters. Shortnose sturgeon spend the predominant portion of their life cycle in fresh water in most of the rivers where they occur, so there is some segregation in populations."

Besides, many scientists noted, there doesn't appear to be a shortnose sturgeon population in the Bay to be impacted. While three shortnose sturgeon were recently caught in the upper Bay, scientists believe the fish most likely swam in through the Chesapeake and Delaware Canal.

Also, some say that the Atlantic sturgeon, though not listed as threatened or endangered, may be in worse shape than the shortnose. "The shortnose seems to be doing quite well in New England - much better than the Atlantic," said John Field, anadromous fish coordinator for the Atlantic States Marine Fisheries Commission, a multi-state panel that develops management plans for migratory fish. "We're seeing plummeting stocks of the Atlantic and increasing biomass of the shortnose."

Meanwhile, USF&WS biologists are combing potential sturgeon spawning grounds in the Chesapeake with high-tech, fish-finding gear in a last effort to determine whether any sturgeon native to the Bay remain. If any were found, it would immediately spur a genetic analysis to determine whether fish native to the Bay are genetically unique from other Atlantic sturgeon populations. Scientists suspect that would be true, as other migratory fish that are spawned in the Bay, such as shad and striped bass, are genetically distinct from other populations.

If a Bay sturgeon were found, it could spark a debate over whether efforts should be undertaken to preserve the native fish before introducing ones from the Hudson River into the system. "But our chances of catching one are slim," said Richard St. Pierre, Susquehanna River Coordinator for the USF&WS. "And if we do, so what? We need two of them."

While Atlantic sturgeon are frequently seen in the Bay - four have been reported by fishermen so far this year - all have been juveniles. And those fish are probably from the Hudson River, not the Bay. Sturgeon typically swim along the coast during the winter, but move into coastal estuaries to feed in the spring.

"The Chesapeake Bay is a big breadbasket, and it's a great area for fish to come in and feed," Musick said.

Occasionally, larger fish have been seen, but not in areas considered to be sturgeon spawning grounds. And no sturgeon less than a year old - the surest sign of spawning activity - has been found in any Bay fish survey since one turned up in the James River in 1979.

Sturgeon are an anadromous fish that are hatched in fresh to brackish water of coastal rivers, but spend most of their lives migrating along East Coast estuaries, where they eat bottom-dwelling organisms. They return to their native rivers to spawn.

Atlantic sturgeon once flourished in the Chesapeake. They were an important part of the diet of early settlers, and during the 1800s supported a major caviar fishery. In the late 1800s, East Coast landings were as high as 7 million pounds a year. But by the 1920s, that had fallen to 22,000 pounds.

The female sturgeon takes anywhere from 15 to 30 years to reach maturity, so once the stocks were depleted, it was difficult for the population to rebound. In addition, the spawning and nursery habitats are located near the fall line of many rivers - areas that were heavily impacted by pollution from nearby cities for much of this century.

"The animals were overfished and spawning in nursery areas that were really uninhabitable," Musick said. "So the animals had a double whammy put on them."

In recent years, only the Hudson River supported any significant fishery at all. This year, Atlantic States Marine Fisheries Commission recommended closing that fishery because of continued stock declines there.

Restoration of the sturgeon has drawn enthusiasm from many scientists and fisheries officials. The fish is a relic from the age of dinosaurs; instead of being covered with scales, it has armor-like plates. The Atlantic sturgeon is much larger, and longer-lived, than other Bay fish. They have been known to live to be 60 years old, reach lengths of 15 feet, and weigh 800 pounds. Though a bottom dweller, the fish are known for occasionally jumping completely out of the water, for reasons that are unknown. Officials also see sturgeon restoration as a long-term commitment to Bay restoration because the fish requires relatively clean water and a healthy population of bottom-dwelling organisms to eat. "It's going to be a very interesting indicator animal," Florence said. "It's going to make sure we keep our habitat suitable for it, so to speak."

Stocking will need to continue for years to develop adequate genetic diversity among the breeding population. The 7,000 fish that may be released this year came from only two females and five males.

The restoration effort will take years to be successful. Females in the Bay region take about 15 years to reach maturity - at a length of about 7 feet - so it will be a decade-and-a-half at the earliest before officials know if this year's stocking effort was successful. (By comparison, it took less than a decade to put a man on the moon from the time President John F. Kennedy made the commitment.)

And actually rebuilding the stock - rather than just getting fish to return - will take even longer. "We're looking at a recovery trajectory of 40 to 50 years," said Field, of the ASMFC.

All the fish released this year will be marked with wire tags so if any are recovered as part of Bay and coastal fish survey programs can be identified. In addition, scientists from VIMS and the University of Maryland's Chesapeake Biological Laboratory are seeking funds to do radio tracking of some of the released fish to monitor their movements and identify what habitats they are using.

After all, many of the conditions in the Bay have changed dramatically since the time sturgeon were abundant. Laboratory work conducted by David Secor, a CBL scientist, indicates that a young fish can probably survive in the low-oxygen conditions and high temperatures it would encounter in the Nanticoke and much of the Bay.

But Secor cautioned that the fish will confront other challenges. Spawning females need to release their eggs over hard substrates - but many such areas have been covered with silt. In addition, non-native species such as channel catfish and largemouth bass are now abundant in some potential Bay nursery areas and may prey on young sturgeon.

"I think something like channel catfish and largemouth bass could do a real number on them," Secor said. "When I talk to Russian colleagues who have worked on the Caspian Sea hatching program, they tell me that catfish is probably the number one problem for stocking."

Despite such uncertainties, Secor said it is important to pursue a stocking program now. "I sense a tremendous amount of support building for sturgeon recovery in the Bay," he said. "I have a feeling that if we lose momentum at this point, it's going to be hard to pick it up again."