Investigators from the Maryland Department of the Environment are searching for what killed 20,000 fish along a four-mile stretch of the Patapsco River last week, Maryland's largest fish kill since the outbreak of Pfiesteria on the Pocomoke River last year.
The fish -- at least five species -- were floating in the river and lying on the banks Dec. 22 between the Avalon Area of Patapsco Valley State Park and U.S. 1, next to Elkridge, said department spokesman Quentin W. Banks Jr.
Environmental officials who visited the scene that day concluded that the fish had been dead at least 24 hours. The species affected included suckers, sunfish, darters, carp and spot-tailed shiners, Banks said.
A member of the environmental group Save Our Streams also reported finding a dead shad.
"We're talking about years for a natural recovery," said John Surrick, a spokesman for the state Department of Natural Resources.
Surrick said a kill of that size probably wiped out a large portion of the fish in that stretch of the river.
Brion Townshend, a community organizer with Save Our Streams, said he was hiking in the area on Christmas when he came upon scores of dead fish.
"They were caught up in the ice and snagged on the brush," he said, adding that he counted 35 dead fish in a 50-yard stretch.
Banks said suspicion initially focused on a Catonsville paper mill that discharges waste into the river under a permit. But investigators found the company's discharge records in order and determined that the problem probably did not originate there.
Officials are searching the records of other companies that have permits to discharge into the river, he said.
Liz Kalinowski, a DNR spokeswoman, said investigators have ruled out Pfiesteria as a cause of the kill. Pfiesteria, a microorganism, is suspected of killing about 30,000 fish in Maryland streams last year.
No 'smoking gun'
"This is the first time we've seen anything like this," Banks said of the Patapsco River kill. "We don't have a smoking gun."
Besides being one of the largest fish kills in recent memory, the event was unusual in that fish kills usually occur in warm weather, Banks said.
No other wildlife appeared to be affected, and officials have seen no evidence of any new fish kills since Dec. 22, Banks said. He said the dead fish will not be collected and will be allowed to decompose.
Charles Wagandt, chairman of the Patapsco Heritage Greenway Committee, said he learned of the fish kill yesterday afternoon and called it "shocking news."
Wagandt was particularly surprised because he cannot remember another Patapsco fish kill in the past 20 years.
"We haven't been hearing of even small fish kills, so I would conjecture that it's an isolated incident," he said. "If it continues to happen then, yeah, that is going to be very frightening."
No records are known to exist detailing the number and kind of fish in the affected stretch of the Patapsco River.
While officials with the state Department of the Environment search for the cause of kill, the Department of Natural Resources is planning to restore the stream.
State to assess damage
Surrick said that, as early as next week, state biologists will go to the area to assess the damage to the stream. If they find that the insects the fish eat survived the incident, they will try to replenish the river with stocked fish in the spring, he said.
"We're going to try to jump-start the recovery of fish in the area," he said.
Pub Date: 12/30/98