After making a strong recovery from massive overfishing due to strict regulations, stripers face a new threat...
ANNAPOLIS, Md. -- Rockfish, whose fortunes in the Chesapeake Bay took a dramatic turn for the better in the 1990s, are in trouble again.
Nearly 75 percent of the rockfish in the bay are infected with a wasting disease that can kill the popular game fish and cause a severe skin infection in humans.
The epidemic of mycobacteriosis took researchers by surprise. As the number of rockfish, also known as striped bass, surged as a result of fishing limits, scientists say they remained in a body of water too polluted to support the level of life it once did.
"We used to think that if you got hold of fishing, all your problems would be solved," said James Uphoff, a biologist at the Maryland Department of Natural Resources. "But now all these ecological problems crop up, and we don't understand them."
An infected rockfish can appear outwardly healthy. But inside, the bacteria settle first in its spleen, and the infection spreads to other organs. The rockfish loses weight, and it often develops sores. At some point -- researchers do not know exactly when -- it dies.
Because the bacteria kill slowly, effects on the stock are only now emerging. And scientists remain baffled about the implications of the disease, including its effects on humans.
Researchers know that the Chesapeake, where most rockfish spawn, also breeds the bacterium and is the epicenter of the disease. But they don't know how or why it appeared, whether it spread to other species or if the infection it causes is always fatal.
Maryland's Department of Natural Resources claims fish safe to eat and catch. DNR Assistant Secretary Mike Slattery said, if handled properly, the risk is minimal.
"This is a reason for concern, this is something we're addressing, but it's not a reason to panic," he said.
In humans who touch the fish, the microbe can cause a skin infection known as fish handler's disease, which is not life-threatening but can lead to arthritis-like joint problems if untreated.
"The fact is that a significant number of fish have the bacteria, that doesn't mean that it is unsafe to handle them if as long as you use the proper hygiene. It certainly doesn’t mean that they're unsafe to eat," Slattery said.
Officials recommend anglers toss back fish that have obvious legions.
"The fact is that this bacteria can cause infection if it's introduced in an open wound or if the spines of the fish were to impale you, but ... if you react with common sense, you're not going to have a problem," Slattery said.
Rockfish In HistoryIn the mid-1980s, rockfish numbers were so decimated by overfishing that Atlantic coastal states imposed a moratorium. The population rebounded, and the fishing ban was lifted in 1995. Wildlife officials called the restoration a rare triumph for the bay, which has seen overfishing and disease threaten blue crabs, oysters and other species.
But less than two years after victory was declared, the first diseased rockfish landed on bay shores.
A new study suggests that since the illness was discovered among bay rockfish, non-fishing mortality among them has tripled in the upper bay. But anglers are not complaining about the volume of their catch, and scientists cannot explain why.
"Scientists attempt to unravel things (and) are supposed to follow the information wherever it leads us," said Victor Crecco of the Connecticut Department of Environmental Protection, author of the mortality study. "We're going to have to do more work to explain these contradictions."
Watermen say the only sick fish they see are in small, overcrowded rivers and streams. The netting season that ended Feb. 28 "was a super-good season as far as catching, and a good season as far as the price," said Larry Simns, president of the Maryland Watermen's Association. With no evidence of health risk from eating the fish, watermen say, prices have remained stable.
Maryland's fishing season opens on April 15.