Warning that outbreaks of a fish-killing microorganism are likely to strike Chesapeake Bay tributaries again next year, Gov. Parris N. Glendening told his commission on Pfiesteria yesterday that it doesn't need to find a smoking gun before recommending strong action.
"I think there will be be some people who will say you have to be 100 percent sure" of the cause of the outbreaks, Glendening said at the opening session of the panel headed by former Gov. Harry R. Hughes. "I'm not sure that is going to be possible."
The 11-member commission, made up almost entirely of nonscientists, has been handed the task of formulating policy responses to the series of Pfiesteria outbreaks that have prompted the closing of three Maryland waterways since last month.
The governor urged the panel to examine urban and rural sources of pollution that might be converting a sometimes innocuous microorganism into a threat to the health of fish and people.
"I would urge you to make your best judgment and use your common sense " he said. "I am prepared to act decisively on your recommendations."
Glendening's charge to the panel is significant because it explicitly dismisses the argument advanced by some rural legislators that "absolute proof" is needed before tighter controls could be imposed on agricultural runoff. Scientists have been pointing to nutrient runoff -- particularly from the Eastern Shore's giant chicken industry -- as a prime suspect in the outbreaks.
The governor warned that some people will lapse into an "out of sight, out of mind" attitude about Pfiesteria when the problem abates because of cold weather. "We should anticipate that as the weather gets warm again we'll have continued outbreaks," he told the panel.
The committee brings together academics, past and present legislators and leaders of some of the most powerful interest groups in Annapolis. Environmentalists, farmers and local officials are represented. Dr. Alfred Sommer, dean of the Johns Hopkins School of Hygiene and Public Health, is the only active scientist.
In a briefing after the governor departed, scientists sketched the outline of a case that nutrient pollution from agriculture is a leading culprit in creating the conditions that turn Pfiesteria to its toxic form.
JoAnn Burkholder of North Carolina State University, the leading Pfiesteria researcher, told the panel that about 75 percent of the fish kills linked to the microorganism have occurred in waters overenriched with such nutrients as nitrogen and phosphorus.
She acknowledged that other scientists have suggested copper compounds might help turn Pfiesteria to a toxic form, but said she is not convinced.
The researcher said nutrients in the water foster the growth of algae, which then attract large schools of menhaden, a common but unpalatable species that is particularly vulnerable to Pfiesteria. Secretions from those fish apparently trigger the benign Pfiesteria's metamorphosis to a toxic stage, she said.
Burkholder said reports of large fish kills involving lesions began to show up on the Atlantic coast in the mid-1980s. But she theorized that the cause goes back many decades, likening Pfiesteria-infested waters to a 30-year smoker who finally comes down with cancer and wonders why it happened in one particular year.
Rob Magnien, director of the Department of Natural Resources' Tidewater Ecosystem Assessment Division, said the answer to the question "why now" could have to do with decreased salinity after a number of years of high fresh water flow into the bay. High water flow also translates into increased runoff, he noted.
Magnien said Maryland's decadelong effort to cut the amount of nutrients in the bay and its tributaries has had widely uneven results.
He said streams on the western Shore, notably the Patuxent River, have experienced as much as a 50 percent cut in nutrients. But on Maryland's Lower Eastern Shore, where the state's Pfiesteria problems have been concentrated, nitrogen levels have increased significantly since 1985, he said.
The likely reason for the disparity, he said, is that the western shore's nutrient pollution came largely from waste water treatment plants, which have since been upgraded. By contrast, Magnien said, the Shore's nutrients come largely from harder-to-control "nonpoint" sources such as farms and homes.
"Agriculture is going to be a big contributor," he told the panel.
Dr. J. Glenn Morris, head of the medical team dispatched to examine watermen and others complaining of memory loss and other ailments, told the commission that some of the patients had come into contact with the water of the lower Pocomoke River before the fish kills that took place last month.
"We do not believe a fish kill is an absolute requirement" for
Pfiesteria-infested water to be dangerous, he said.