COLUMBIA, Pa. -- Once, American shad swam up Atlantic coastal rivers in huge masses each spring, when instinct -- or some inner compass -- lured them by the millions from the ocean to their ancestral spawning beds.
Schools of the fork-tailed fish ruled the Chesapeake Bay and ran rivers like the Potomac, Susquehanna, Hudson and Connecticut in huge migrations. Shad from the Delaware River played a part in the American Revolution, feeding George Washington's troops during their historic crossing.
Today, however, few people under age 40 may have heard of the fish, a member of the herring family that is indigenous to the Atlantic and a species that once constituted a major commercial fishery.
American shad -- a brawny species that can grow to 30 inches long -- have been locked out of their natal rivers for much of the past century, thwarted by dams built to power mills, feed canals and generate electricity. In other places, such as the Delaware River near Philadelphia, contamination created "pollution blocks" that prevented them from reproducing.
But the tide is again shifting in favor of the shad.
Dam removal and hatchery programs, stricter pollution controls, construction of fish passage systems and fishery restrictions in the Atlantic are all helping. And nowhere is the comeback more convincing than in Pennsylvania.
In the past few years, on the Susquehanna, Juniata, Delaware, Schuylkill and Lehigh rivers, shad are again darting upstream, mating -- and then usually dying -- in places they haven't haunted in years.
The fish are making similar returns to rivers in New England and in other states that include Virginia, Maryland and North Carolina.
In Pennsylvania, the state Fish and Boat Commission has driven the restoration effort, removing 60 dams in the past six years and releasing millions of hatchery-raised shad "fry" to ensure populations can rebound.
There is clear evidence shad are coming back.
On a sweltering July evening on the Susquehanna River at Columbia, three men in a flat-bottomed fishing boat paid out 100 feet of nylon net. The men, employees of a consulting firm hired by the commission to help measure the ratio of wild shad to stocked shad in the river, motored out from a small island and back, jumped ashore and began hauling in the net. Lure-sized American shad -- the largest about 3 inches long -- flipped like silver flapjacks in the net, along with a few crawfish and other species, which get tossed back.
"Oh, we got 'em here, boys," said Steve Adams, looking with a practiced eye at a shad fingerling. He dropped it into a bag and counted them: 14 in all. Seining at five other spots that night yielded eight more fingerlings, later packed in ice for pickup by the fish commission.
Last year, sampling on the Susquehanna showed about half the shad netted were wild -- an encouraging sign, said Scott Carney, a fisheries biologist with the commission.
The restoration effort is important to anglers, but it also contributes to the health of rivers' ecosystems, said John Olney, an associate professor at the Virginia Institute of Marine Science, near Virginia Beach.
American shad and its cousins, hickory shad and blueback herring, are food sources for bass, walleye, muskie and carp. Those fish, in turn, are food for birds and other animals hunting the river, Olney said.
Other states are pursuing similar dam removal and shad stocking strategies in an effort to help the fish return. And an agency that sets fisheries guidelines for East Coast states is helping by restricting shad fishing in the Atlantic. By Jan. 1, 2003, Atlantic states must reduce commercial shad catches by 40 percent; a complete moratorium will begin in January 2004, according to the Atlantic States Marine Fisheries Commission.
The commercial catch of American shad from the Atlantic in 1999 weighed in at about 1.4 million pounds, a dramatic drop from the 9 million pounds caught in 1950. The 1999 shad haul was worth about $984,000, according to the fisheries commission.
On Virginia's James River, "stocks of shad had been at dangerously low levels since 1990," Olney said. In 1994, the state and federal wildlife officials began stocking shad fry, and in the past two years, Olney said, "We've seen large influxes of hatchery-raised fish, and higher catch rates."
In Maryland, scientists found evidence recently of a shad spawning run in the Patuxent and Choptank rivers for the first time in years.