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A Vampire Story
. . . Or how I learned to stop worrying and love the lamprey
Fly Rod & Reel June 2004
So all this means that we should desist from controlling freshwater sea lampreys and kiss them Jimmy Houston style, right? Well, no. First, if it were possible to extirpate them from habitat they seem to have evolved in, we shouldn't; but it's not possible. Second, they aren't native to the upper Great Lakes; and, although it's not possible to extirpate them there either, it would be nice to. And third, the lamprey problem in lakes Ontario and Champlain is indeed the result of alien introductions-but the aliens are stocked salmonids, not (apparently) the sea lampreys with which they can't cope. The only solution is aggressive lamprey control.
Before the lamprey invasion the United States and Canada annually harvested about 15 million pounds of lake trout from the upper Great Lakes. Then, between 1937 and 1947 the Lake Huron catch dropped from 3.4 million pounds to about nothing. Between 1946 and 1953 the Lake Michigan catch fell from 5.5 million pounds to 402.
Managers started work on the problem in 1946 when a team led by Michigan DNR biologist Vernon Applegate began interdicting lampreys with barriers. But the researchers quickly realized they'd also need a selective poison, and there'd never been such a thing for any pest, let alone fish. Still, three years later Applegate and his colleagues began what he called "a six-year sentence of unmitigated boredom," testing about 6,000 chemicals by dumping them into 10-liter glass battery jars that contained a rainbow trout, a bluegill and a larval lamprey.
Finally in 1955 lab chief John Howell found one jar in which the lamprey was dead and the trout and bluegill "alive and happy." At first he thought something had gone wrong. But when he tried again he got the same result. Unfortunately, the chemical-3-bromo-4 nitrophenol-was expensive and almost impossible to synthesize. So Applegate turned to Dow Chemical Co. for help. Dow suggested testing close chemical relatives, then concocted some soluble formulations. The winner was 3-trifluoromethyl-4-nitrophenol (TFM), still used today and as close to a silver bullet as chemical pesticides get. Non-target mortality is almost nil. Occasionally, when dosages are off, young mudpuppies (large aquatic salamanders) are killed. But numbers swiftly rebound, and in roughly 3,000 TFM treatments over the last 40 years not one population is known to have been lost.
No lamprey control was more effective than water pollution. For example, the St. Marys River, which runs from Lake Superior into Lake Huron, produced few lampreys before it was brought back to life by the Clean Water Act. At 25 times the size of the biggest river ever treated with TFM, there had been nothing managers could do but watch the cleaned-up St. Marys pump vampires back into Lake Huron.
But in 1998 the Great Lakes Fishery Commission tried a new selective lampricide called granular Bayluscide. Grains of sand are coated with the poison, then coated again with a time-release substance. Applied to hot spots by helicopter, the lampricide sinks and spreads over the bottom, allowing non-target fish to swim up or away. After Bayluscide treatments on the St. Marys, and release of sterile males that tie up multiple females in unproductive spawning, scarring of Huron lake trout declined by 50 percent. There are still problem areas in the Great Lakes (upper Lake Michigan, for instance), but the sea lamprey is the one alien invader (out of 165) that managers have learned how to control. Today Great Lakes sea lampreys are down 90 percent from their 1961 peak. The control program costs about $12 million a year and produces income-from sportfishing-of between $4 and $6 billion a year.
Lamprey control is forever. But without it, says the commission's Marc Gaden, "Endangered species would be wiped out, and we'd have no fishery to speak of, just a cesspool of exotic organisms that have infested our waters." In Europe, where sea lampreys fetch as much as $25 per pound, they've traditionally been relished as gourmet food. Crazed with gluttony, King Henry I of England is said to have killed himself with a "surfeit of lamprey." We plunder our dogfish for the Brits; why not plunder our lampreys for them and get paid for it? But when I put the question to Gaden he said the commission needs every male lamprey it can get its hands on for its sterile-release program. "The last thing we want is to be competing with commercial fishermen." The commission traps lampreys, kills the females (which are fat with eggs and lack the spinal ridge), then runs the males through a machine that weighs them, figures out the right dosage of sterilant, shoots it into them, then dumps them into a holding tank.
In 1990 Vermont, New York, and the US Fish and Wildlife Service (having finished a five-year, 997-page Environmental Impact Statement (EIS) that restudied everything the lake states and Canada had learned about TFM since the 1950's) finally got around to using TFM in Lake Champlain's tributaries. The results on the Atlantic(?) salmon fishery were spectacular. "Some of the guys were fishing the Ausable, Boquet and Saranac instead of going up to the Gaspe," reports Larry Nashett of the New York Department of Environmental Conservation. "Up there they might spend a lot of time and money and catch one fish. Here, on good days, they were taking three-fish limits." The better salmon were seven or eight pounds. There was even some natural reproduction.
But when the EIS expired in 1997, it seemed as if Vermonters had never heard of TFM; the stuff terrified them. At this point Vermont, New York and the US Fish and Wildlife Service undertook a two-year, 579-page "comprehensive evaluation" of the eight-year program and-when this was hatched-a two-year, 562-page supplemental EIS, in which they restudied everything they'd restudied in the first EIS.
Since the end of all the studies in 2001, New York has been knocking the bejesus out of lampreys on its side of the lake. But because of low water in 2001 along with public chemophobia and ongoing timidity among health officials, there has been only one TFM treatment in Vermont-on Lewis Creek in 2002. Meanwhile, the salmon fishing in 2003 was the worst in recent memory, according to district fisheries biologist Brian Chipman.
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