Invasive zebra and quagga mussels are firmly established in the Great Lakes, and efforts to control them have proved mostly fruitless. But environmental managers still want to know where they are, how many there are and what they are up to, so they can predict how the ecosystem will be affected and protect vital infrastructure.
Keeping track of the invaders, however, is an expensive and time-consuming task, usually involving divers and collection scoops deployed from boats that can physically sample the mussels. Read more in Great Lakes Now.