Fish lesions scarce so far Healthy harvest from site of 1997 Pfiesteria outbreak

May 10, 1998|By Heather Dewar | Heather Dewar,SUN STAFF

SHELLTOWN -- Watermen and state biologists are hauling in a surprising harvest from the pearl-gray Pocomoke River: healthy fish. Striped bass and catfish, croaker and perch without the characteristic lesions of Pfiesteria piscicida -- all of them taken from waters where the toxic microorganism was ravaging fish this time last year, and where a repeat outbreak has long been expected.

Prompted by a Pocomoke City doctor's report that he is treating a man who developed Pfiesteria-like symptoms while fishing at the river's mouth three weeks ago, two biologists from the Maryland Department of Natural Resources netted 799 fish in that area Friday and yesterday.

None of the fish had the characteristic bloody sores on the underside that signal Pfiesteria, and only four showed scratches, scrapes or illnesses of any kind -- a rate below the usual 1-in-100 ratio of fish abnormalities, according to DNR spokesman John Surrick.

Local watermen say they're surprised by the scarcity of problems in the fish they are catching, compared to April and May of the past two years, when bloody, sick fish were a common sight in their nets.

"You see a fish every now and then with something on it, but nothing like we had last year, when you'd see fish half-gone," said Fred Maddox, whose seafood company near Williams Point lies less than a mile upriver from the site of last summer's worst outbreaks.

"We have not found one fish with problems," said the Rev. Bob Daniels, a Crisfield pastor and part-time crabber who has been ++ checking the fish that turn up in his crab pots. "Every fish we have is clean. I don't believe we have it anymore."

State officials aren't making any bold predictions.

They say only that there's no evidence Pfiesteria is active in Chesapeake Bay waters. Since February, DNR biologists have sampled "tens of thousands of fish with no problems" at sites throughout the bay area, said Surrick.

Because the worst fish kills were in the Pocomoke, it's an area of concern. "Going out there and seeing only healthy fish is a hTC reasonable indication that there is not a Pfiesteria problem in that area," Surrick said. "A significant number of fish that were caught in that area last April and May had serious abnormalities, and we're not seeing that now."

But it's maddeningly difficult to be sure of anything where Pfiesteria is concerned. Researchers think Pfiesteria usually lies harmlessly buried in bottom sediments, emerging only when fish are abundant, to attack them. The current theory is that humans can get sick from airborne toxins when Pfiesteria is at very high levels in the water -- but the toxic outbreaks seem to last 12 hours or less, leaving few traces behind.

'This year's first case'

Dr. Ritchie Shoemaker, who has treated several dozen sick people and suspected Pfiesteria was to blame, thinks a brief outbreak sickened his latest patient.

Shoemaker said the man, who asked not to be identified and has refused to talk to state officials, was fishing for pleasure near Williams Point in mid-April and caught "some rockfish that had some lesions."

The man briefly suffered from burning eyes and skin, stomach cramps and diarrhea -- but he didn't see a doctor, didn't report the incident and didn't save the fish. The man consulted Shoemaker this week, complaining he had been short of breath and "incredibly tired" since the incident.

The doctor calls it "this year's first case of Pfiesteria exposure syndrome." He said he thinks the toxic organism "has been present at low levels all winter long." But that's impossible to confirm, because tests that would detect Pfiesteria in water or in humans are in an experimental phase.

DNR biologist Harry Rickabaugh, who serves on one of the state's three newly created "rapid response teams" for tracking down suspected Pfiesteria outbreaks, said, "People need to report things as soon as they find them "

'Chunky little guys'

Rickabaugh and partner Bennie L. Williams ran three sets of six-minute trawls in the waters off Williams Point yesterday, using a weighted net called an otter trawl to catch fish near the river bottom where Pfiesteria is most likely to be found.

Under a gray mist reflected in gray water, the two men sorted through 522 fish from five different species -- white perch, white catfish, hog choker, striped bass and young croakers.

"Chunky little guys. They're in good shape," said Williams, examining dozens of minnow-sized croakers caught in the net. The two men found four fish with minor scrapes and scars, none resembling Pfiesteria's distinctive lesions.

The biologists plan to search the Pocomoke again today. If no sick fish are found, they'll move on to other rivers.

As part of DNR's Pfiesteria-tracking efforts, the rapid response teams are netting fish and taking water samples on the Pocomoke, Chicamacomico and Manokin rivers and Kings Creek, where toxic forms of the microbe were found last year, as well as on the Nanticoke, Wicomico, Big Annemessex and St. Martin rivers and Newport Bay, where no outbreaks are known to have occurred.

Pub Date: 5/10/98

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