Zebra mussels spread across all Great Lakes within a decade of arriving in 1988

In the late 1980s, an aquatic invader quietly entered North America through an unlikely route: a ship’s ballast water. That species was the zebra mussel, and within a decade it had spread across all five Great Lakes, triggering one of the most notorious invasive-species stories on the continent. More than three decades later, the same tiny shellfish is still making headlines; this time in Texas, where officials have now declared Lake Meredith fully infested and identified it as a possible stepping stone for further westward spread.A small mussel with a big impactZebra mussels are native to Eurasia, but once they arrived in North America, they adapted fast and spread even faster. According to the USGS, they are a problem because they cling to hard surfaces, multiply rapidly, and can damage ecosystems, native species, and infrastructure.