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Invasive Species

Invasive species are organisms that have settled in a habitat where they don’t belong. Invasive species are often introduced by humans accidentally or on purpose. They can have devastating effects on the local ecosystem because the native species have not evolved to deal with the invaders. Sometimes, the native species are even at risk of extinction.

The Sea Lamprey

The Sea lamprey is native to the Atlantic Ocean. The first sighting of the Sea lamprey in the Great Lakes was in 1835 in Lake Ontario. Although the Sea lamprey normally inhabits saltwater, it was able to adapt to the freshwater in the Great Lakes. The fish in the Great Lakes had not evolved to deal with the enormous Sea lamprey. The result was complete decimation of the local fish population. In the Atlantic Ocean, the Sea lamprey rarely kills its host fish, but in the Great Lakes, the Sea lamprey turned from parasite to predator and killed large numbers of fish.

The Sea lamprey was destroying the fishing economy of the Great Lakes region. Luckily, scientists found a chemical that kills the Sea lamprey without harming the local fish. Now this lampricide (a pesticide that targets the Sea lamprey) is used every year to control the Sea lamprey population. The Great Lakes ecosystem is currently in good health, and the fishing industry is doing well. 

The Great Lakes region is home to four native lamprey species. Some of them are parasitic and some aren’t. Because these lampreys have co-evolved with the native fish, the fish rarely die from being attacked. In fact, these lampreys play an important role in keeping the Great Lakes ecosystem healthy. The native lampreys are helpful for the ecosystem (including the fish), so we want to keep them around.
The invasive Sea lamprey is the one we need to eliminate.