This story was originally Appeared in Yale Environment 360 is part of climate desk collaboration.
“Thousands of sea lampreys are passed upstream [on the Connecticut River] every year. This is the predator that wiped out the Great Lakes lake trout fishery. [Lampreys] It literally sucks the life out of its host fish: smaller fish such as trout and salmon. Fish ladders should be used to reduce lampreys. ” So I edited eagle tribune Lawrence, Massachusetts, December 15, 2002.
If that’s true, why this spring Trout Unlimited, one of the country’s leading advocates for trout and salmon, is supporting the town of Wilton, Connecticut, and an environmental group called Save the Sound to extend sea lamprey spawning habitats over 10 miles. I am doing a project to restore. The Norwalk River that flows into Long Island Sound?
Why this summer, the first big harvest from stockpiled Pacific lampreys (a species similar to sea lampreys) climbed the Columbia River Dam’s specially designed lamprey ramps, bringing history to the states of Oregon, Washington and Idaho. Will it soar into a popular spawning habitat?
And when the Connecticut River’s Turners Falls canal is cleared in September, why are the Connecticut River Reserve, the Fort River Basin Association, and the Biocitizen Environmental School rescuing stranded sea lamprey larvae?
The answer is ecological awakening. That is, the gradual realization that if nature as a whole is good, no part of it is bad. In their native habitat, the sea lamprey is a ‘keystone species’ that supports vast aquatic and terrestrial ecosystems. They provide food for insects, crayfish, fish, turtles, minks, otters, vultures, herons, loons, ospreys, eagles and hundreds of other predators and scavengers. Maintain water quality with filtered feeding. And by releasing pheromones, it attracts egg-laying adults from the sea. Adults die after spawning, so they inject nutrients from the sea into the sterile headwaters. When marine lampreys build communal nests, they remove silt from riverbeds and provide spawning grounds for a myriad of native fish, especially trout and salmon.
Environmental consultant Steven Geffard, former Connecticut migratory fish chief, calls the lamprey an “environmental engineer” as important to a unique ecosystem as the beaver.
Sea lampreys, which lived about 340 million years ago, rely on cool, free-flowing freshwater for spawning. They are boneless, jawless, eel-like fish with fleshy fins. They extract fluids from other fish via toothed suckers. Both sea lampreys and Pacific lampreys have been identified as “ugly”, and when sea lampreys gained access to the waters of the upper Great Lakes via man-made canals, possibly the Welland Canal, which bypassed Niagara. , has been widely criticized for depleting endemic fish species in the Great Lakes. waterfall. Once there, they nearly wiped out the valuable commercial and sport fisheries of lake trout (the largest char species, not true trout like rainbow trout, cutthroat and brown).
By the 1960s, the invasive sea lamprey had reduced annual commercial use of lake trout in the upper Great Lakes basin from about 15 million pounds to 500,000 pounds. In 1955, Canada and the United States established the Great Lakes Fisheries Commission. This commission manages lampreys with barriers, traps, and a highly selective larval toxin called TFM. Eliminating lampreys costs him $15 million to $20 million annually. Without it, continued lake trout recovery would be impossible and all other sportfish populations would collapse.
