Zebra Mussel

invasive species · freshwater · molluscs · accidental travelers

Tiny striped shellfish. Zebra mussels are small freshwater molluscs with a hard shell, and they get their name from the dark stripes running across their white or cream-colored shells, kind of like a zebra's pattern.

Accidentally invaded everywhere. These mussels originally came from lakes in Russia and southeastern Europe, but they hitchhiked around the world in the ballast water of ships and got loose in places like the Great Lakes, Hudson River, and many other North American lakes since the 1980s.

Serious ecosystem troublemakers. Zebra mussels are considered one of the world's most invasive aquatic species because they multiply so fast and damage freshwater systems by clogging pipes, competing with native species for food, and changing how lakes and rivers work.

Hitchhiked on ships. Scientists believe zebra mussels spread from Europe to North America by getting into the ballast water that ships use for balance, then getting released into new waters far from their original home.

Multiply super fast. Zebra mussels can reproduce quickly and in huge numbers, which is why they're so hard to control once they arrive in a new lake or river.