Invading Zebra Mussels Found in the Chesapeake Bay

The nation’s largest estuary may become infested without public intervention.

(Photo: Peter Yates/Getty Images)

Dec 19, 2012· 1 MIN READ
The director of the Public Trust Project, Alison Fairbrother has written for Grist and Politics Daily, among others.

Zebra mussels may sound exotic and delicious, but these invaders are bad news for American waterways, and the news just got worse.

This month, biologists discovered 20 young zebra mussels hanging out on buoys in the Chesapeake Bay off Havre de Grace, Maryland. Zebra mussels are invasive mollusks that were accidentally carried over on a ship coming from the Caspian Sea in the 1980s.

Named for their distinctive striped pattern, Zebra mussels live in fresh and brackish water, and have a bad habit of outcompeting native species for food. Ever since their arrival 25 years ago, zebra mussels have been marauding through America’s Great Lakes and rivers towards the Bay. It was only a matter of time before they began making inroads in the nation’s largest estuary.

MORE: Barry Levinson's 'The Bay': A Harrowing Fiction Meant to Save the Real Chesapeake

Maryland researchers are worried about what these mollusks will do to the Chesapeake Bay now that the population has landed.

“In their wake, zebra mussels cause economic damages in the billions of dollars, killing imperiled native freshwater mussels, and disrupting aquatic ecosystems,” Ron Klauda, a biologist from Maryland’s Department of Natural Resources, said in a press release.

The U.S. Army Corps of Engineers has a beef with them too.

The agency has called zebra mussels “the most troublesome freshwater biofouling organism in North America,” because of the mussels’ tendency to cluster together on pipes and underwater equipment, clogging piping and pumps at waste water treatment plants.

Zebra mussels have a pattern to their infestation. After a mussel invades a lake, it rapidly expands its population until there are enough mussels to spill out into an adjoining river, where the mollusks will coat the bottom of the river for hundreds of yards, blocking other animals from foraging on the Bay floor, according to the Chesapeake Bay Journal.

But not all habitats are ideal for these vicious mussels to proliferate. Time will tell whether the zebra mussel population in the Chesapeake Bay will take off. Until then, biologists are asking for your help. Because the little mollusks have no natural predators, only humans can keep their populations in check. And effective management of invasive species like zebra mussels is only a pipe dream without the help of concerned citizens.

The Maryland Department of Natural Resources has called on boaters and recreational fishermen to be on the lookout for the mussels, and has recommended that boating from place to place be limited—especially from a zebra mussel-infested area like to a pristine area.

“We’d rather not have them in Maryland waters, but they’re now established in the Susquehanna. So far, that’s the only place in the State where we’re convinced they’ve taken hold,” Klauda wrote. "We’re asking our boats and anglers to be vigilant and help prevent their spread to other waters.”