The sea lamprey, native to the Atlantic Ocean, originally entered the Great Lakes in the early 20th century through shipping canals before wreaking havoc on the Great Lakes fishery, killing fish in huge numbers. (Photo: T. Lawrence, Great Lakes Fishery Commission)
Below the waters of the Great Lakes lurks the stuff of nightmares. The invasive sea lamprey, also known as the “vampire fish,” is a long snake-like creature with a suction cup mouth ringed with concentric rows of sharp teeth. Growing up to 60 centimetres long, the parasitic fish latches onto the side of other fish, then extends it’s tongue and drills a hole through the fish’s scales and skin. Once it’s in, the lamprey feeds on its prey’s blood and bodily fluids.
To make matters worse, the population in the Great Lakes exploded during COVID-19. Lake Huron alone has seen a dramatic increase from about 100,000 to nearly 200,000 sea lampreys. The sea lamprey, native to the Atlantic Ocean, originally entered the Great Lakes in the early 20th century through shipping canals before wreaking havoc on the Great Lakes fishery, killing fish in huge numbers. Since then, cross-border programs were put in place to control numbers using a lamprey-selective pesticide. But the program was curtailed in 2020 and 2021 because of travel restrictions related to the pandemic.
While efforts are back underway to drive numbers down again, this could take a few years. Sea lampreys are extremely good at bouncing back, with females able to produce up to 100,000 eggs at a time.
Sea lampreys are not a danger to humans and don’t feed on warm-blooded creatures. A sliver of good news, at least.