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Zebra Mussels

Zebra Mussel Fast Facts

Name: Zebra Mussel (Dreissena Polymorpha)

Size: 80 microns to 45 millimeters

Description: Organism is characterized by a light and dark varying stripped pattern resembling zebra stripes on two connected hard shells.

From Russia with love

The Zebra Mussel originates from the Balkans, Poland, and the former Soviet Union. This little bivalve is thought to have traveled across the Atlantic to America on commercial ships from Eastern and Southern Europe. Originally discovered in the Great Lakes in 1988, zebra mussels are now found in 29 states including Texas in Lake Texoma.


Zebra mussels are bivalves with two asymmetrical shells connected by a ligament called a hinge. These two hard shells protect the soft body from the elements and predators.

Why the zebra mussel has to go

Several dozen species of bivalves hang their hats in Texas and it may seem that a new little bivalve in the neighborhood would be no big deal. Not the case. One zebra mussel can produce 30,000 to a million offspring in just one year.  Zebra mussels grow quickly and in some cases can become sexually mature in 3- 12 months, living for two to three years.  They latch onto any hard surface in water, including rocks, rope, pipes, and other bivalves. By multiplying so quickly and attaching to hard surfaces, zebra mussels can shut down a city’s water supply by colonizing inside pipelines. They can filter out an aquatic ecosystem of its smallest nutrients, leading to declines in the fish population. They can also sink buoys and docks and damage boats, and other structures in the water. Millions of dollars are spent each year to control, clean, and monitor zebra mussels  in the U.S.

Baby zebra mussels, called veligers, are microscopic in size and float in clouds of thousands in the water. This makes transportation of the mussels virtually undetectable in improperly drained bait buckets, boat motors and livewells. These tiny mussels attach themselves to surfaces early in life becoming detectable only after they have grown.  After the initial American discovery in Lake St. Clair, Michigan in June 1988, zebra mussels were found in all five Great Lakes by September 1991 and throughout the Mississippi River basin.

How to prevent the spread

Texas Parks and Wildlife Department officials request boaters traversing the state’s waterways to  Clean, Drain and Dry their vessels to help prevent the spread of zebra mussels from one lake to the next.

Boaters are asked to first clean their boat or trailer of all vegetation, mud and algae, then to drain all water from motors, livewells, bilge, and other sources of water retention. Finally boaters are asked to let boats and boating equipment dry for about a week between uses in different water bodies. TPWD recommends letting your boat or other vessels dry for 7-10 days in the summer, or 15-20 days in the cooler months. The invasive zebra mussel is known to spread between water bodies by hitching a ride on recreational watercraft such as motorboats and jet skis, as well as in bait buckets and other fishing equipment

Zebra Mussels in the news and research