A Michigan State University researcher has discovered an interesting phenomenon: sea lampreys go into what appears to be a panic-mode when exposed to the smell of their dead.
Dr. Michael Wagner found that when a mixture which included the putrefying carcasses of sea lampreys was poured into a tank of live ones, the lampreys’ frantic efforts to escape were dramatic.
"It’s kind of like a stop light, a noxious odor that causes them to run away from its source," Wagner said.
While it makes for some rather freaky videos, it turns out that this reaction may be key to better controlling one of the most destructive invasive parasites found in the Great Lakes.
Sea lampreys live off of the blood and body fluids of adult fish, including lake trout and whitefish. During its life, each sea lamprey can kill 40 or more pounds of fish.
"Sea lampreys are one of the most costly and destructive Great Lakes' invaders," said Wagner, whose results were published in the July issue of the Canadian Journal of Fisheries and Aquatic Sciences. "The effectiveness of the odor combined with the ease in which it’s obtained suggests that it will prove quite useful in controlling sea lampreys in the Great Lakes."
Currently, pheromones -- the same chemicals the lampreys rely on to attract mates and find spawning grounds -- are used to lure the creatures into large cages where they can be destroyed or sterilized and released back into the wild.
Wagner believes that repellants could be a better alternative since even small quantities can elicit a response. The smell of death could be used to steer lampreys away from waterways or corral them into groups, making them easier to eliminate.
"By blocking certain streams with these chemical dams, sea lampreys can be steered away from environmentally sensitive areas and into waterways where pesticides could be used more effectively to eliminate a larger, more concentrated population of sea lampreys."