REEDS BEACH, N.J. - The 42-foot boat pitched and yawed in the Delaware Bay waters as fishermen pulled in the net for the last time, ending their monthlong search for the elusive Atlantic sturgeon.

The net was empty. But these fishermen had already found their quarry. Five adult specimens of the prehistoric-looking fish, whose eggs are prized worldwide for caviar, had been collected in gill nets over the previous 30 days.

A last-day encounter with another of the sword-nosed, spindly-looking fish "was just not meant to be," said Capt. Brick Wenzel, in that matter-of-fact, man-of-few-words way of a seaman.

After fears that Atlantic sturgeon would become extinct prompted a 40-year East Coast sturgeon fishing moratorium in 1996, watchdog groups like the American Littoral Society and scientists from the National Marine Fisheries Service are hoping for a comeback in the Delaware Bay.

In the first study in New Jersey, the Littoral Society, a Sandy Hook-based coastal watchdog group, commissioned Wenzel and first mate Rick DelSordo to begin what they hope will be a multi-year study to count the Atlantic sturgeon in the bay.

Atlantic sturgeon have been around for 75 million years. Eating mostly worms, snails, shellfish, crustaceans, and small fish, they can grow to 15 feet long, weigh as much as 800 pounds and live as long as 60 years.

In the 1890s, they were so plentiful in the Delaware Bay that trains made daily runs to ports in New York and Philadelphia with as many as 30 boxcars of caviar – "black pearls."

But something happened just before the turn of the century that left Atlantic sturgeon as rare as Delaware Bay oysters.

Within a four-year span in the 1890s, landings of Delaware Bay sturgeon plummeted from about 2,000 tons per year to just over 100 tons annually, according to historians. Overfishing and pollution in the years since have almost driven the fish to extinction.

"I was lucky to have made a good living in the fishery when it was still active in the 1980s and early-90s," Wenzel said. "Now I have a chance to help give something back, for science."

While no wildlife survey counts every individual fish, bird, or four-legged creature that may be stirring in any given habitat, quantifying a sampling within a specific area can give researchers a good snapshot of what may be going on beneath the surface, according to Dery Bennett, a Littoral Society spokesman.

The data collected on Wenzel's vessel will help researchers determine whether there is a genetically distinct stock of Atlantic sturgeon spawning in the nearby rivers or if they mingle with sturgeon from the Hudson Bay.

The research may also help scientists determine more precisely what caused such a thriving fishery to falter nearly 100 years ago.

The information could be key in the Atlantic sturgeon's future, Bennett said.

As adults, Atlantic sturgeon swim in the ocean close to the shoreline, migrating between Canada and Florida. After 20 years of growth, they swim up rivers in the spring to spawn, laying eggs near where saltwater and freshwater mix.

In the Delaware River, they once spawned just below Trenton. Scientists have now determined that they are spawning some 30 miles downriver, just below Philadelphia.

So back to the ancient spawning grounds, the brackish waters of the Delaware and Maurice Rivers, Wenzel and DelSordo were sent to set their 600-foot gill nets.

"With this study, we're trying to create a better understanding of this unique species and its place in the ecosystem of this region," said Bennett. "Ultimately, the goal is to restore a thriving population of this species that deserves to be here as much as any other."

The Littoral Society hopes to win foundation or government funding for several more years of $35,000-a-year research, Bennett said.

For 30 days straight, the entire month of April, rain or shine, burning 100 gallons of diesel fuel a day, the men made the 30-mile round trip into the bay to the net site.

To begin the survey, Wenzel and DelSordo set their web of 12-inch-wide monofilament mesh nets. This involved sinking the fish traps to depths of about 20 feet. The nets were weighted by markers so they wouldn't float away and could be easily spotted and avoided by other boaters.

Then they went back to roll in the nets and see what the currents had brought.

When they were lucky enough to have netted a sturgeon, the fish was brought on board, measured and weighed. Then a tiny identification tag with a toll-free phone number was attached to the sturgeon's back, so if the fish is caught, whoever finds it will know the fish is part of a study group.

On the way back from the seven-hour journey recently, Wenzel looked out the windshield of Salty's Tours, a trim commercial vessel, and envisioned what it must have been like in the day of the sturgeon on this bay, when hundreds of boats plied the waters for sturgeon and their roe.

The quantity and quality of the caviar was so robust that Russia was among New Jersey's largest customers.

Near-forgotten towns such as Bayside in Cumberland County were so populated by people working in the fish processing plants that they warranted twice-daily passenger train service from Philadelphia.

But by the 1920s, the sturgeon fishery had all but dried up in New Jersey. Demand for the tiny black-pearl fish eggs was still high, but overfishing, poor fish management and pollution led to a decline.

"It's a shame what happened to this fishery," Wenzel said. "Maybe this study can help turn that around."

To view a slideshow of the search for sturgeon, go to http://go.philly.

com/sturgeonEndText

Contact staff writer Jacqueline L. Urgo at 609-823-9629 or jurgo@phillynews.com.