Measures are finally taken against an aggressive invasive species It crossed the great lakes in Ontario.
The peak of Sea Lampreys sparked a joint campaign between Canada and the United States to protect freshwater fishing by $ 5.1 billion in the region.
The control crews began treatment at the end of April to reduce the population of 
The work began in Lake Érié and Lake Ontario and will probably continue until October. Some of the population control methods include lampride (chemical treatment), traps and barriers.
Maritime lampreyAlso known as vampire fish, were accidentally introduced by shipping channels in the big lakes in 1921. They use their mouths with 150 teeth and serrated languages to attach to prey, killing up to 40 pounds of fish during their parasitic phase.
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Before controlling the maritime lamprey, the species killed many more fish than humans, causing considerable economic and ecological damage.
The mouth of a maritime lamprey includes 150 teeth and a tongue which is sold.
Steve Russell / Toronto Star via Getty Images
A new study confirms that lamprey figures have increased sharply during the COVVI-19 pandemic. Travel restrictions in 2020 and 2021 forced the crews to suspend treatments and millions of lamprey larvae survived accordingly.
Ethan Baker, chairman of the big lakes’ fisheries commission, said the increase was expected.
“The continuous and constant control of the maritime lamprey is of extremely important importance to prevent damage to the fish of the great lakes by invasive maritime lampreys,” Baker said in a press release on April 10.
“Research shows that the control of the maritime lamprey must continue each year to keep the populations of this invasive species harmful in check.”
In 2024, the enumerations of adult maritime lamprey were 8,619 above the pre-cuvids-19 averages. Lake Superior and Lake Ontario have experienced the largest increases. Figures in the Michigan, Huron and Erie lakes are starting to stabilize.
“If we are removing the foot from the gas, even for a short time, the populations of maritime lamprey will increase rapidly and will cause considerable damage to fish,” said Baker.
Control efforts have since resumed, but scientists and managers warn that the damage caused during the break will take years to reverse.
“Control of maritime lamprey is essential to protect the prosperity of the region,” said Baker.
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