Fish virus fears float to surface

Fish virus fears float to surface

Not much is known about an emerging fish virus that has infiltrated and killed fish on several of the lower Great Lakes, but it hasn't been found yet in Lake Simcoe or Georgian Bay. Viral hemorrhagic septicemia (VHS) has the potential to seriously deplete fish stocks in Ontario rivers and lakes, the Ministry of Natural Resources says. It's safe for humans to eat fish infected with VHS, which has been found in 16 fish species in Ontario, including walleye, chinook salmon, yellow perch, muskellunge and round gobies. "It hasn't appeared to have much of an effect on rainbow trout, at least that we know about," said John Johnson, the MNR's commercial fishing program co-ordinator.
"The bottom line is there's not much known about it." There could be serious ecological, social and economic impacts if the virus continues to spread to Ontario’s inland waters, the ministry says. "There's probably is no way to stop it," Johnson said. "The cure is to stop transmission to lakes that don't yet have it." Lake Simcoe has been added to the MNR's priority list for sampling and testing, which should begin this year. "There are quite a number of water bodies in Ontario that we've identified as having a likelihood (of becoming infected with VHS) that we've put on our priority list," Johnson said. Where the virus is present, most fish deaths happen when the water is 18C or colder. "There have been no huge impacts so far," Johnson said, "but we're taking a wait-and-see attitude." Moving bait fish infected with VHS from southern Ontario into waters in central and Northern Ontario will spread the virus and damage fish populations. To stop the spread of VHS, the province has been divided into three sections — infected, buffer and virus-free zones — to regulate live bait fish. Emerald shiners and bluntnose minnows, both used as live bait fish in Ontario, are two of 37 species that can carry VHS. One of the best ways to stop VHS from spreading, Johnson says, is to buy and use live bait in the same area where it's purchased. Anglers should also disinfect their boats and live wells after they've fished in VHS-infected waters.