Americans confront fishery threat
Kingston Whig-Standard Dec. 27, 2006
By Paul Schliesmann
U.S. states along the Great Lakes and St. Lawrence River have banned the sale and transportation of live fish caught in waters infected by a deadly virus.
Viral hemorrhagic septicemia (VHS) causes fish to bleed to death. And it appears to be establishing itself quickly in Canadian and U.S. waters, particularly the Great Lakes and St. Lawrence River, appearing in at least 14 species of fish.
A series of public meetings will be held around New York State in January, alerting the public to the problem and informing them how they can help slow the movement of the virus.
Here in Ontario, the issue is barely on the public radar.
“I'm not sure why you're not hearing too much about it north of the border,” said Doug Stang, chief of the bureau of fisheries with the New York State of Environmental Conservation in Albany. “But you should be hearing about it.”
According to Stang, on the New York side last summer, “The bottom of the St. Lawrence was reputedly littered with dead gobies.”
No one cares much about gobies, the European invasive fish that appeared in the Great Lakes in the 1990s. But other important sport fish such as muskellunge, smallmouth bass and pickerel may be dying in significant numbers.
“We think we lost quite a few muskies the past few years,” said Stang. “Hundreds.”
But while American officials are moving ahead, Canadian officials have taken a wait-and-see approach.
“It's been percolating,” said John Cooper, a spokesman for the Ontario Ministry of Natural Resources Lake Erie Management Unit, “but we haven't had that many situations where VHS has been linked to die-off.”
Cooper said there was one mass die-off of freshwater drum and round gobies in the Bay of Quinte in May of 2005. “The fish died and we didn't know what caused it.”
Tissue samples later helped identify the virus as the culprit.
Since then, said Cooper, a new test has been developed for the virus and it has helped determine where the disease may have come from.
Originally, it was thought VHS was transported here in the ballasts of ships from Europe, where the virus has been present for decades in salmon and trout.
But Cooper said the strain found in the Great Lakes fish is genetically closer to that found in fish on Canada's Atlantic and Pacific coasts.
“This is the fourth strain of this virus identified in the world,” he said. “The question is: how did it work its way upstream through the St. Lawrence and the Great Lakes?”
But in the U.S., there is less concern with how it got here and more emphasis on keeping it out of inland waters.
On Oct. 24, the U.S. Department of Agriculture inspection service imposed a federal order banning “the importation of certain species of live fish from Ontario and Quebec,” as well as the transporting of these species between the eight states bordering the Great Lakes.
Live bait is seen as the main method of transporting the disease. If larger fish eat infected bait and are released back into the water, then they could become carriers of the virus.
That's why live bait can't be used in bodies of water other than where they originated.
He said there has already been a negative effect on the live bait industry in New York, which he described in economic terms as “big.”
Though he didn't have dollar figures for the New York side of the business, Stang said the industry in Ontario is valued at about $100 million a year.
At this point, no one can predict how major a problem VHS may become.
“It can potentially infect all species of fish,” said Stang. “We aren't exactly sure how this is going to play out. The earliest fish we have are muskellunge from the St. Clair River in 2003. It's too early to tell. It's
here relatively recently.”
Cooper said Canadian officials are working on a plan for this spring, but he didn't have details.
The federal Department of Fisheries and Oceans, which is doing the fish surveillance work, and the Canadian Food Inspection Agency, which will speak on behalf of Canada internationally, are both operating with natural resources in Ontario on the issue.
Spring is considered a critical period. The virus is most active at four to seven degrees celsius, just as local waters are warming and the spawning season begins.
Fish are particularly vulnerable in the spring, said Cooper, because they are weak after a long winter and have low energy levels, making them susceptible to disease.
They also shed the virus during spawning, possibly spreading it to other fish.
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