Department of Fish and Wildlife
Half million carp dead; worst appears over
FRANKFORT, Ky. –
worst of a fish kill that has claimed upward of a half million Asian carp in
the Cumberland River below Lake Barkley dam is believed to be over.
On Friday, April 25, fisheries biologists with the
Kentucky Department of Fish and Wildlife Resources returned to the area as the
focus shifted to learning what might have caused the considerable die-off of
invasive silver carp.
“Anglers were seeing dead fish a week ago, some two weeks
ago, which is very typical of a fish kill caused by some type of viral
pathogen,” said Paul Rister, western fisheries district biologist with Kentucky
Fish and Wildlife. “It’s kind of a bell-shaped curve. You start seeing a few
die, and a few more die, and then you reach the peak of the massive die-off. I
think we’re on that downhill side now.”
After conferring with Asian carp researchers from around
the country, Kentucky Fish and Wildlife Fisheries Director Ron Brooks said the
belief among experts is that the fish kill found below Barkley Dam to the
Cumberland River’s confluence with the Ohio River is the largest ever involving
Asian carp in the United States.
Silver carp, which are not native to the United States,
appear to be the only fish affected. To help move the mass of fish downriver,
the U.S. Corps of Engineers on Thursday opened three gates at Barkley Dam to
flush dead fish downstream.
“I don’t think people have to worry about those pathogens
affecting native species,” Brooks said. “That’s probably the best news of all.”
While the cause has not been confirmed, possibilities
include overstress from spawning or the presence of a pathogen that disrupts
brain function in the fish, Brooks said.
“Any time you have an event where there are a lot of fish
congregating, it’s just like any other animal, the chance for a pathogen to
spread increases,” he said. “Whether it’s that pathogen or some other stressor,
no one will know until we get word from the researchers.”
Dying silver carp collected from the area by Kentucky
Fish and Wildlife will undergo disease testing at Kentucky State University.
Kentucky Fish and Wildlife also is working the U.S. Fish and Wildlife Service
as well as agencies from bordering states and Purdue University.
Fisheries biologists visited nearby Kentucky Lake dam
Friday after receiving reports of dead Asian carp on the Tennessee River. After
investigating the area, the cause of death of those fish is believed to be due
to bow anglers and snaggers.
Asian carp find the Cumberland and Tennessee rivers
hospitable because the water discharged from Lake Barkley and neighboring
Kentucky Lake is so fertile, Brooks said.
He is hopeful researchers find something from this fish
kill that leads to the eventual eradication of Asian carp. Silver carp are
plankton feeders and threaten the well-being of native fish and mussels by
over-harvesting that vital source of nutrition.
“It’s comforting to know there’s something out there that
might take these things out before they just devastate everything,” Brooks
said. “Right now we just don’t have it.”