Invasive 'vampire fish' populations spiking in the Great Lakes
In their native environment, the Atlantic Ocean, sea lampreys don't often kill their host. In the Great Lakes, where sea lampreys have not co-evolved alongside native species, they are a significant threat.
An invasive vampire fish is causing a stir in the Great Lakes after COVID-19 safety measures put population control measures on the back burner.
There are four native lamprey species in the Great Lakes - the American brook lamprey, the chestnut lamprey, the silver lamprey, and the northern brook lamprey.
The sea lamprey is invasive and can cause problems in local ecosystems. That has a lot to do with its size. Sea lampreys are large compared to native species - up to four times larger.
The Great Lakes Fishery Commission handles population control, a group comprised of wildlife experts from Canada and the U.S., Fox News reports.
But in 2020 and 2021, efforts scaled back significantly due to the pandemic. The results of that are now apparent because there is typically a "two-year lag time" before crews can determine the success of a campaign, Marc Gaden, deputy executive secretary of the Great Lakes Fishery Commission, told Fox News Digital via email.
He says the population spike was first observed in 2022 will likely continue into 2023.
The problem with sea lampreys
Sea lampreys can inflict gruesome damage on their prey, earning these eel-like parasites the nickname "vampire fish."
A sea lamprey will destroy upwards of 18 kgs of fish in its lifetime, and only about one in seven fish attacked by one will survive, the Government of Canada writes on its website.
It will suction itself to a fish, creating a seal that's nearly impossible to remove.
They have about 100 teeth, which they use to suction to the side of a fish, and a sharp tongue that drills through its scales. Lampries secrete an enzyme that prevents blood from clotting. Once attached, it will spend the next several months feeding off the blood and fluids of the host animal. A lamprey will then move on to another fish.
Fish that dislodge a lamprey are often left with wounds that can become infected, ultimately killing the fish.
How did sea lampreys get into the Great Lakes?
Sea lampreys entered the Great Lakes from the Atlantic Ocean through man made shipping canals, popping up in Lake Ontario in the 1830s. When the Welland Canal deepened in 1919, sea lampreys gained access to all the Great Lakes, and they remain there to this day.
In the 1950s, the U.S. and Canada teamed up to implement population control measures, which have proven effective.
Several strategies - including traps to capture adult lampreys, a chemical called lampricide that targets larvae, and installing barriers are a few tactics in use.
Today, sea lamprey populations are down by 90-95 per cent in the Great Lakes when compared to before control efforts were in place.
Are lampreys a threat to humans?
Sea lampreys can accidentally latch on to humans, usually when people are swimming. A bite won't be fatal, but it can be painful, and untreated wounds could lead to infection. Sea lampreys don't pose a threat to people - they aren't interested in us, and human bites appear to be rare.
In their native environment, the Atlantic Ocean, sea lampreys don't often kill their host. In the Great Lakes, where sea lampreys have not co-evolved alongside native species, they are a significant threat.
VIDEO: More about sea lampreys here
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