In the 1880s, there was a gold rush of sorts along the Delaware River.
Hundreds - perhaps thousands - of fishermen flocked to camps along the waterway, taking to the river each day in the hope of landing a fish so prized that a single good catch could bring a year's worth of income.
Their prey was the Atlantic sturgeon, a remnant of the age of the dinosaur that can grow to 14 feet and is so ugly that some refer to it as the Franken- fish.
Its eggs valued as caviar, the sturgeon was the backbone of the region's fishing industry. Millions of barrels of roe were shipped all over the globe.
But early this century, after only a few decades of intense fishing, the species all but disappeared from the region.
Now, biologists hope, it may be returning.
And this has prompted another heyday, of sorts, for the fish, if only in biologists' lab books and folklore programs re-creating an all-but-forgotten time.
"This fish has been overlooked for the past 100 years," said Craig Shirey, a biologist with Delaware's Division of Fish and Wildlife, who is among those working to change that.
On Monday, he and two helpers were out in the Delaware just off the Salem cooling tower, hauling in 1,200 feet of net and hoping for a portent - enough of the huge, weird fish to indicate more conclusively a comeback for the species.
Shirey, who will set nets throughout the summer, has been monitoring the sturgeon population in the river for four years. In that time, he has tagged 1,700 sturgeon pulled from the river and noted their recapture as far away as Maine and North Carolina.
"There's just very little that we know overall, so everything we do is breaking ground," Shirey said.
New Jersey officials have staked out the Atlantic Coast, monitoring the sturgeon at sea. Biologists at a U.S. Fish and Wildlife lab in Lamar, Pa., are experimenting with ways to incubate sturgeon eggs in a controlled setting to replenish the population.
Researchers elsewhere are mapping the sturgeon's genes, analyzing its flesh, liver, gonads and stomach contents - all in an attempt to find out what makes this ancient fish tick. And what will bring it back from the precipice.
Few, however, expect to restore the population to its teeming numbers of a century ago, when each spring, residents were treated to the spectacle of waves of sturgeon coming up the Delaware in the fresh water off Philadelphia.
