"We want to reassure anglers that while we are concerned about the LMBV and will continue to monitor the situation, there are no bass virus fish kills occurring now and the virus is not a reason to cancel any fishing trips," said Kim Erickson, fisheries chief for the Wildlife Department. "Although some of the bass in certain Oklahoma lakes are carrying the virus, populations are in good shape overall, and fishing is good to excellent in most places. Additionally, the presence of the virus poses no threat to human health if fish are properly prepared and consumed."

Erickson noted that based on previous experiences fisheries professionals believe the LMBV will not cause long-term damage to bass populations. To date, LMBV has been found in Lakes Tenkiller, Grand, Ft. Gibson, Hudson, and most recently, Lake Texoma. In the case of Texoma, Texas Parks and Wildlife fisheries biologists recently sampled largemouth bass in the 89,000-acre border lake and determined that eight percent carried the LMBV.

"What we now know is that this virus is not always a major problem and that it's not always lethal to fish," Erickson said. "It's just out there in the environment, and when conditions get right we may have some fish die. We're not certain, though, what it is that actually triggers the virus into becoming the disease. It some cases it may be so minor that anglers don't even notice, but when it impacts a fishery like Lake Tenkiller, it gets noticed."

According to Auburn University scientist John Grizzle, LMBV is one of more than 100 naturally occurring viruses that affect fish but not warm-blooded animals. Its origin is unknown, but it is related to a virus found in frogs and other amphibians and almost identical to a virus isolated in fish imported to the United States for the aquarium trade.

Although the virus apparently can be carried by other fish species, to date it has produced small numbers of deaths only in largemouth bass. Researchers have discovered that LMBV can stay alive in water for at least three to four hours. This suggests that anglers could unknowingly transport the virus in a livewell, bait bucket or in bilges. Bass can contract the virus from contact with other fish, but it is still not known how the virus is activated into a fatal disease. Most importantly, there is no known cure or prevention for LMBV.

The disease first gained attention in 1995, when it was implicated in a fish kill on Santee-Cooper Reservoir in South Carolina. Since then, the virus has been found in water impoundments throughout the South and portions of the Midwest. The virus has been detected in bass that show no signs of illness, which suggests that some fish might be infected but not ever become sick.

Biologists are uncertain about how long the virus has been present in Oklahoma waters, but the pattern suggests that unusually hot summer temperatures were a catalyst in the die-offs. The good news, Erickson noted, is that although angler catch rates, particularly for large fish, decline for a short period of time following an LMBV-related fish kill, they usually recover within a year or two.

"Because the virus appears to strike a fishery and move on, answers to the LMBV mystery have been hard to find," he said.

For more information on largemouth bass population surveys conducted by the Oklahoma Depar-tment of Wildlife Conservation, or for a weekly fishing report, log on to the Department's website at www.wildlifedepartment.com.
http://www.WildlifeDepartment.com/NewsRelease/050301/virus.rtf

(taken from the ODWC's weekly email)