Biologist Hugh Lefcort has spent years watching a mysterious slaughter of innocent families at the bottom of the food chain.
Slime-footed, shell-backed snails defy natural instincts of self-preservation in Lefcort’s laboratory, serving themselves up as escargot for hungry rainbow trout and other predators.
The Gonzaga University assistant professor can turn these peaceful organisms of Northwest waterways into suicidal lemmings by exposing them to a few ounces of toxic soil from the Coeur d’Alene River basin. Numbed by lead, zinc and cadmium found in the sediment, the snails wander carelessly out of hiding even when trout swim by.
Lefcort can’t explain the death wish. But the phenomenon has forged a discomforting theory in his mind - snails tainted by heavy metals are easy prey for trout; trout engorged with snails may be eaten by people.
The theory, if it holds up in field tests, could raise questions about the safety of consuming fish raised in Lake Coeur d’Alene and the Spokane River.
“Snails are a good indicator of the ecosystem. They’re the canary in the coal mine,” Lefcort said from his campus office overlooking the Spokane River. “I wouldn’t fish on the Spokane River.”
Lead and other heavy metals can cause learning disabilities and sickness. That’s why the government banned leaded gasoline.
However, fishing enthusiasts say they doubt the Spokane River’s trout are dangerous to eat.
“I would concur that if snails are available to trout, trout will chomp down on them. Lead, PCBs, zinc or whatever is in them goes right up the food chain,” said David James, Spokane chapter president of Trout Unlimited, a conservation group. “But there’s no data to back this up. I don’t think there’s a significant health hazard to eating fish.”
Ray Duff, regional fish biologist for the Washington Department of Fish and Wildlife, said the state has issued no health warnings about trout in the 110-mile-long Spokane River.
“They (trout) don’t appear to be at levels of a health hazard,” Duff said. “We simply tell people that they shouldn’t have a consistent diet of fish.”
But other scientists are intrigued by Lefcort’s claims.
“There’s a complex system out there, and we don’t know everything that’s going on,” said Mike Beckwith, biologist with the U.S. Geological Survey in Sandpoint, which has studied life in Lake Coeur d’Alene. “If he (Lefcort) publishes the results, it would be quite an advancement to the overall state of knowledge.”
Lefcort, Gonzaga chemist William Ettinger and several students have submitted their research to a pair of scientific journals. They expect it to be published this year.
But getting published doesn’t necessarily make it true, and Lefcort is the first to admit there are variables in the wild that could alter his theory. He plans to replicate his tests at several sites in the Coeur d’Alene basin this summer.
It may take months for toxic metals to move from snails into trout, Lefcort said. In addition, no one knows whether trout loaded with metals become as willing to be caught as snails do.
Lefcort is not an environmental extremist. The 35-year-old Seattle native eats steak and owns two old Saabs, one which spews heavy exhaust.
He became interested in analyzing the behavior of tiny organisms while a graduate student at Oregon State University, where he earned a doctorate.
“Frogs don’t matter, snails don’t matter, but people matter,” said Lefcort, who pays for his research on snails and tadpoles with a $15,000-per-year grant from the Murdock Foundation Charitable Trust.
Scientists studying contamination in the Coeur d’Alene drainage have focused on the amount of heavy metals in water, sediment, fish and animals. The metals came from a century of Silver Valley mining, scientists say.
Lefcort has taken a different approach by measuring whether the metals affect the behavior of primitive organisms in the food chain.
He bred thousands of snails in 20-gallon buckets. During the summer, the buckets were placed on the roof of Gonzaga’s Hughes Hall. He also built a system of tubs and plastic pipes to simulate a stream in his laboratory.
When trout are added to the water, the snails pull into their shells or hide under rocks and ledges, Lefcort says.
Likewise, the alert snails hide when researchers add a few drops of water from a trout tank or bits of crushed snail. They “smell snail on their breath,” Lefcort joked.
But after adding one quarter cup of dirt from the upper Coeur d’Alene River, snails and tadpoles act dangerously indifferent to the fish.
In short, they are eaten.
“If the trout are predominantly eating the easy-to-get snails,” Lefcort said, “then they are getting a whopping dose of metals.”
, DataTimes ILLUSTRATION: Color photo
Click here to comment on this story »