Once again, one of our outdoor resources is being threatened. Just as occurred with invaders such as lamprey eels, zebra mussels, round gobies, and diseases such as whirling disease in trout and chronic wasting disease in deer, the presence of a unique strain of Viral Hemorrhagic Septicemia (VHS) could be devastating to our freshwater fish. Once a fish is infected with VHS, there is no known cure, and almost every species of warm or cool water fish in the state is susceptible to the virus. The virus is harmless to humans.
The VHS strain we're dealing with was initially discovered in Michigan's muskellunge in 2003 By 2005 it was found in the Bay of Quinte in Lake Onatrio's Canadian waters where it killed muskies, drum and gobies. In May 2006 there was a massive die-off of gobies in Lake Ontario and the St. Lawrence River. A month later, large muskies were found dead from the disease in these same waters. That same summer many other species of fish, both game and pan species, in those waters were found dead or dying from the virus. By August the VHS had spread to Conesus Lake, where a major die-off of walleye occurred.
The VHS viruses were initially discovered in Europe in the mid twentieth century, and in 1988 it was reported in spawning salmon in the Pacific Northwest and was determined to be a new strain of the virus (Type IV) that appears to be uniquely North American. It is widespread in the Pacific herring and cod populations in the Pacific Northwest and has also been found in Atlantic herring and Greenland halibut in the Atlantic Ocean. As far as anyone can tell, it was never detected in North American fresh waters prior to 2003. A strain of VHS in Europe infected rainbow trout reared in commercial ponds, and the mortality there was nearly 100 percent. But the virus strain we're dealing with can infect 40 different species of fish, making it potentially one of the deadliest aquatic diseases this continent has seen.
The physical symptoms of VHS include bulging eyes, sores or signs of bleeding around the eyes, bases of the fins, sides and head, and corkscrew swimming behaviour. So far, VHS has been detected in muskellunge, smallmouth bass, northern pike, freshwater drum, lake whitefish, gizzard shad, yellow perch, black crappie, bluegill, rock bass, white bass, redhorse sucker, round goby, burbot, walleye, chinook salmon, bluntnose minnows and emerald shiners.
To affect as much protection against the spread of VHS to more waters, the DEC has installed special regulations. One restricts the personal use of baitfish to the specific water body and its immediate tributaries from which such baitfish were collected, with no motorized, overland transport allowed. It also requires that baitfish offered for sale be certified disease free of fish pathogens and accompanied by a fish health inspection report. There are also regulations that govern which waters anglers are allowed to use baitfish, as well which waters where the commercial collection of baitfish is allowed. For more on this, go to www.dec.state.ny.us/website/dfwmr/propregs/#10e.
However, even with these regulations in place, an equally dangerous method of spreading the disease is not just with bait, but with boats, canoes, kayaks or any watercraft that is transported from one water to another. The DEC advises that totally spraying the crafts, along with trailers and motors, if present, with a ten percent mixture of bleach and water kills the VHS pathogen, but everything must be completely covered by the spray solution.
