In Portugal, sea lampreys are worth about $23 a pound and are served with a sauce of blood and vinegar. In Minnesota, they are an unwanted nuisance.
University professors at the Minnesota Sea Grant are trying to cater to the tastes of the Portuguese while helping control the fish’s population in the Great Lakes.
“Commercial harvest could possibly fit into a control strategy,” said Jeff Gunderson, acting associate director of the sea grant program. “It won’t be a control in itself, but it would be a tool that could be used in some cases.”
During the 10 months of a lamprey’s adult life cycle, it can kill about 40 pounds of fish.
“They have that suction type mouth and a rasping tongue,” Gunderson said. “And they rasp a hole in the fish and suck out their body fluids.”
The fish, an exotic species in Minnesota’s waters, was introduced to the Great Lakes in the 1900s when they found a way around Niagara Falls. They reached Lake Superior in the 1940s.
The Great Lakes Fishery Commission, a group made up of U.S. and Canadian officials, spent about $20 million last year to control the lamprey population. The commission uses a combination of pesticides, trapping and the sterilizing of males.
Right now, Gunderson and others are awaiting the results of surveys taken in Portugal to learn whether there would be a market for Minnesota lamprey there. The group also conducted a taste test in Duluth last summer in which the fish got a fairly good response.
Gunderson described the eel-like fish as a unique eating experience, and said it was possible that people in the U.S. would consider eating lamprey when they want an exotic food, like escargot.
“It’s hard to describe the flavor,” Gunderson said. “It’s a dark fish. My wife said it reminded her of eating beef.”
Many questions remain as to whether it would be practical to ship lamprey to Portugal. Gunderson said the group doesn’t know how many lampreys could be caught or whether it would be practical to ship them. The Portuguese are accustomed to buying live fish.
Peter Sorensen, an associate professor in the Department of Fisheries and Wildlife, is also researching ways to control the population. He is looking into producing lamprey pheromones and using them to lure the fish into traps.
Only the female lampreys that are caught could be used as food because the males are sterilized and released, Sorensen said. When these males mate, they produce eggs that don’t hatch, and each female can produce about 100,000 eggs.
“They’re worth more alive than dead,” Sorensen said.
The fish are often caught in remote areas and in small numbers, Sorensen said.