BY JOHN RICHARDSON

Maine Sunday Telegram

The Chesapeake Bay, as the fish swims, is more than 400 miles from the coast of Maine.

But no place is more important when it comes to saltwater sportfishing in northern New England.

"That's the generator of our striped bass," said George Lapointe, commissioner of Maine's Department of Marine Resources. "That's where they go to spawn and that's where they grow up. So if the Chesapeake Bay suffers, we suffer too."

And Chesapeake Bay is suffering.

Decades of pollution from farms and development sprawl have eroded water quality and created a so-called dead zone in the bay. Now, a bacterial disease is infecting Chesapeake's striped bass, and killing an unknown number of them.

Anglers and officials in Maine worry that the poor health of the nation's largest estuary is causing a decline in striper catches here and threatening one of the East Coast's healthiest and most valuable fisheries.

This month, in fact, concern about the disease and the declining catch in Maine helped convince East Coast fisheries managers to reject a proposal to expand the commercial catches in Chesapeake Bay and other areas.

Tens of thousands of Mainers and visitors converge on the coast here each summer and fall to try to catch striped bass when the powerful fish swim north to feed on mackerel, menhaden and other bait. Like several other states, Maine does not allow commercial fishing for striped bass. Recreational anglers, however, spend about $25 million a year on food, fuel and bait and support a fleet of about 140 active charter boats.

Other marine fish -- mackerel, cod, sharks -- attract anglers, but stripers are the big prize.

"People up here hold striped bass in very high regard," said David Pecci of Bath, a coastal fishing guide. Not only are stripers the foundation of Maine's recreational saltwater fishing industry, but, said Pecci, "we almost lost them."

The striped bass population along the East Coast crashed in the 1980s because of overfishing and other problems in Chesapeake Bay. The population recovered in the 1990s and is now considered the most valuable recreational fishery from Virginia to Maine.

Some troubling trends

The population is still considered healthy, although down from its peak, according to scientists advising the East Coast states. But conservationists and coastal regulators say they are closely watching some troubling trends in the 180-mile-long Chesapeake Bay.

"We do have concerns about the status of the Chesapeake stock right now," said Bill Goldsborough, a scientist for the nonprofit Chesapeake Bay Foundation and a member of the Atlantic States Marine Fisheries Commission.

One widespread concern is the drop in the number of young fish throughout the range, from North Carolina to Maine. Another, Goldsborough said, is the drop in catches in Maine, which sits at the northern edge of the range for fish that migrate from the Chesapeake. The fact that fish have been plentiful south of Cape Cod but more difficult to catch in New Hampshire and Maine is called "range constriction" and may signal larger problems, he said.

Maine's catch was down 31 percent in 2008, according to state records. The catch rebounded a little this past summer, but was still well below average, according to anglers. Smaller fish were especially rare, they said.

"Usually the small fish will migrate a certain distance" from Chesapeake in order to spread out and feed on bait fish, said Gary Nelson, a fisheries biologist and striped bass expert with the Massachusetts Division of Marine Fisheries. "When (striper numbers) drop, then they're just going to find the best habitat closest to them and stick around there."

One of the biggest concerns up and down the coast is mycobacteriosis, a lethal bacterial disease that is usually associated with farmed fish rather than wild ones. While the disease first attacks internal organs, it eventually causes sores or lesions on the sides of the fish.

Cause unclear

It first showed up in the late 1990s, and now infects three out of every four of the stripers that stay in Chesapeake Bay year round. A smaller portion of the fish that migrate out of the Chesapeake each summer also have the disease.

"We don't see a lot of telltale signs on the fish that come up here," Pecci said. "We saw a rash of it a few years back. Now, occasionally we'll see one."

The cause of the disease outbreak is unclear, although many point to the bay's poor water quality and low oxygen levels and a lack of food for the bass.

Because it is similar to bacterial strains that are known to infect humans, anglers in Maryland and Virginia have been advised to wear gloves when handling striped bass, especially if the fish have visible sores on their scales. While the fish are considered safe to cook and eat, officials there advise throwing them back to avoid handling them.

Officials in Maine say there has not been enough evidence of a health problem here to issue a similar advisory.

Scientists in Virginia and Maryland now say the disease is taking a toll on the population, although how much of a toll remains unclear. A four-year fish tagging study indicates fish with advanced stages of the disease were half as likely to survive the period of study as healthy fish, said John Hoenig, a professor at the Virginia Institute of Marine Science, part of The College of William and Mary in Gloucester Point, Va.

"It's fascinating from an academic point of view, but it's discouraging from an ecological and fishing point of view," Hoenig said. "We know that it's causing mortality in parts of the stock, and we don't really know what that means."

Hoenig and other scientists say it's too soon to know if the disease is doing enough damage to the population to be the cause of the declining number of young fish or the declining catch in Maine. But, he said, researchers hope to find out.

"Now that we see that it does have impacts, a logical next question is, 'Where are those impacts going to be felt?'"

In Maine, anglers and officials are increasingly concerned about what's happening farther south. There is no getting around the fact that the fate of Maine's saltwater sport fishery rests in the troubled Chesapeake Bay, said Pecci, the charter boat captain from Bath.

"Until we can see large spawning-year classes, consistently, in the Chesapeake," he said, "I'm not sure what we can expect for a fishery up here."