HARRISBURG, Pa. – The Pennsylvania Fish and Boat Commission (PFBC) has announced that laboratory tests have confirmed that the Koi Herpesvirus (KHV) is responsible for the deaths of thousands of carp in Crawford County’s Pymatuning Reservoir, located in Pymatuning State Park.
The virus does not affect humans, and should not be considered a risk to human health.
The deaths were first discovered late last month, primarily on the Ohio side of the reservoir. No sick or dead carp were observed by PFBC staff in the eastern portion of the reservoir commonly referred to as the Pymatuning Sanctuary. The sanctuary is separated from the main waterbody by a narrow dam and small spillway.
Live carp were collected by PFBC staff on September 12 and shipped to the University of Minnesota’s Aquatic Invasive Species Research Center for testing. This marks the first time that the virus has been confirmed in Pennsylvania waters.
The lab confirmed on September 21 that the fish had tested positive for the Koi Herpesvirus. The virus is known to affect only carp and koi, and there is no known way to eliminate it.
The source of the virus is unknown. It could have been carried by infected fish or present in bilge water, or could have been in backyard pond or aquarium fish someone may have released into the lake.
The PFBC urges anglers and boaters to protect the Commonwealth’s waterways by not transporting live fish between waters and by always cleaning their gear.
“We want to remind anglers and boaters that it’s imperative to clean their gear after each fishing or boating trip, particularly if they are moving between waterways,” said Brian Niewinski, Chief of the PFBC’s Fish Production Services. “This is the best way to prevent the spread of viruses and aquatic invasive species.”
PFBC biologists believe the deaths have peaked, but they caution that there is evidence that fish which survive KHV may retain the virus for long periods of time, resulting in fish becoming carriers of the pathogen. As such, it should be expected that the Pymatuning reservoir will experience similar periodic outbreaks over the next several years.
Visit the PFBC website for more information on how to “Clean Your Gear” and stop the spread of aquatic invasive species.