A vampiric, ray-finned fish is reportedly startling anglers in the Great Lakes, but an aquatic wildlife organization says it has gotten the population under control despite recent sightings.
Sea lampreys, an eel-like fish that’s native to the Northern Hemisphere but is considered invasive in the Great Lakes, experienced a brief population spike during the COVID-19 pandemic, and authorities have spent the last year removing the lamprey surplus.
The Great Lakes Fishery Commission, a bi-national commission where wildlife experts from the U.S. and Canada work together to protect Lake Superior, Lake Michigan, Lake Huron, Lake Erie, and Lake Ontario, have been responding to the lamprey population.

"Sea lamprey control is ongoing," Marc Gaden, deputy executive secretary of the Great Lakes Fishery Commission, wrote in an email to Fox News Digital.
"Control is targeted where sea lamprey larvae live," Gaden continued. "Control is achieved through the use of a lampricide — a pesticide discovered in 1957 that is selective to lamprey at the concentrations applied."
Between 2020 and 2021, lampricide applications were reduced significantly as crews responsible for administering the pesticide faced logistical challenges in light of the pandemic, which reduced control efforts, according to Gaden.
He noted that the sea lamprey control generally results in a "two-year lag time" before lampricide crews know how successful a field season was.
"For instance, the survivors of 2020 (and there were a lot because, as I said, COVID kept the field crews from traveling) return to spawn in 2022," Gaden wrote. "We did see a spike in numbers in 2022 and we expect to see the same in 2023 (the survivors of the curtailed 2021 season)."
"They are incredibly destructive."
— Marc Gaden
He continued, "We've been hitting the lamprey hard in 2022 and 2023, so we're hoping the COVID spike was a blip."
While the Great Lakes Fishery Commission has deployed sea lamprey control efforts throughout the Great Lakes, anglers are still spotting the eel-like parasitic fish, which have rows of sharp teeth. They have reportedly been seen attached to other fish, or there's been evidence that the lampreys have taken a bite out of their scaly neighbors.
A recent article published by The Wall Street Journal (WSJ) found that fishing guides, charter captains, and tourists have seen sea lampreys and caught wounded trout, salmon, and other fish from Lake Superior, which encompasses parts of Minnesota, Wisconsin, Michigan, and Ontario, and Lake Michigan, which encompasses parts of Michigan, Wisconsin, Illinois, and Indiana.
Anglers have had to hold wounded catches at certain angles in order to photograph their catches in a more appealing way, according to the WSJ, but they’ve also snapped images showing the lampreys on fish and bites that the lampreys apparently take.

Despite the unsettling appearance of sea lampreys, the parasitic fish doesn’t pose a known health risk, and fish that have been attacked by lampreys can still be consumed if desired, according to research available in the National Ocean and Atmospheric Administration’s (NOAA) online library.
"Fish that have been attacked by lamprey bear a circular wound or scar. Edible. If open sore, remove inflamed area; clean fish and prepare as usual," states a 1982 NOAA-supported article titled, "Parasites: Are the Fish Good Enough to Eat?"
The article, which was written by Jeff Gunderson, who at the time was a fisheries agent with the University of Minnesota’s Sea Grant Extension Program, was successfully compiled and published thanks to the NOAA’s Office of Sea Grant.
While not common in present-day North America, sea lampreys have been consumed in various parts of the world throughout history, including in parts of Europe (England, Portugal, Spain, France, Sweden, Finland, and Baltic countries) and South Korea, according to New World Encyclopedia.
The United States Geological Survey reports that sea lampreys are "an ancient species" that have retained "primitive ancestral characteristics from millions of years ago," which includes a slim body, two closely spaced dorsal fins, seven gill openings on each side, a large round mouth with curved razor-like teeth, and a rasping tongue.
Sea lampreys are parasitic and can kill 40 or more pounds of fish during their adult life, according to findings from the Great Lakes Fishery Commission.
The parasitic fish are native to the northern and western Atlantic Ocean and made their way to the Great Lakes in the 1920s through shipping canals.
"They are incredibly destructive," Gaden wrote to Fox News Digital. "The Great Lakes Fishery Commission, under a treaty with Canada, began a sea lamprey control program in 1958 that has reduced sea lamprey populations by about 90-95% throughout the basin, allowing for the emergence of a Great Lakes fishery now worth more than $6 billion annually."
The presence of sea lamprey in the Great Lakes varies in each body of water. The Great Lakes Fishery Commission publishes adult sea lamprey abundance estimates for each lake on glfc.org.
Current data for the Adult Lamprey Abundance Index state that Lake Superior and Lake Huron are "above target" while Lake Michigan, Lake Erie, and Lake Ontario are "meeting target."
"Sea lampreys are slimy, opportunistic, resilient beasts that will destroy tens of millions of pounds of Great Lakes fish given the chance," Gaden wrote. "Control is successful and does not give sea lampreys that chance. But, like a bad penny, sea lampreys are here to stay, unfortunately. But we can control them."