What are they?
Zebra and Quagga mussels are freshwater molluscs. They first arrived in the ballast water of ships from the Baltic Sea in the 1980s, and are highly invasive.
Miniature, but mean!
The impacts of these tiny mussels are devastating to ecosystems, infrastructure, economies, culture, and recreation.
They can survive for several weeks without being immersed in water, if they’re left in a cool and moist environment (for example, on an undried boat).