What is Zebra Mussel?

About Zebra Mussel:

• Zebra mussels are an invasive, fingernail-sized mollusk.
• Scientific Name: Dreissena polymorpha
• Distribution:
• They are native to the Caspian and Black Seas, south of Russia and Ukraine.
  • They entered the Great Lakes of North America in the late 1980s through ballast water discharged from ships.
  • Since then, they have spread through much of eastern Canada and the United States.
  • Habitat: They live underwater, attached to natural and manmade substrates such as rocks, wood, plants, native mussels, pipes, docks, boat lifts, swim rafts, moored watercraft, and other debris. 
• They are easy to identify, with a distinct, flat-bottomed ‘D’ shape to their shells that allows them to sit flat against a solid surface, and black, zigzag stripes against a cream background that earned them their name.
• They grow around two inches long at most, and are microscopic in their larval stage, which is known as a “veliger.”
• They are short-lived (between two and five years), and begin reproducing at two years of age.
• Impacts:
  • They are filter feeders that attach themselves to virtually any surface.
  • They breed very quickly, as females can release up to one million eggs each breeding season.
  • They disrupt food webs by wiping out phytoplankton.
  • Zebra Mussels are especially harmful for native mussels, many of which are species at risk. They outcompete these species for food and will attach themselves to native mussels, suffocating them.
  • Their massive clustering on water-intake valves and pipes, bridge abutments, and other structures can cause severe commercial damage.