Quagga mussel

Dreissena rostriformis bugensis


Photo credit: ©Sergey E. Mastitsky
Dreissena bugensis
  • It lives in estuarine habitats, lakes, and water courses.

  • Dreissena bugensis commonly has alternating light and dark brown stripes, but can also be solid light brown or dark brown. It has two smooth shells that are shaped like the letter “D”.
  • These mussels are usually less than 2 inches in length. In new populations, most mussels are young and therefore very small (under ¼ -inch long).
  • Zebra mussel and the quagga mussel are very similar in their appearance.
  • They can sometimes be differentiated by the shape of the shells. However, expert knowledge is needed to distinguish these two species.

Download N.I.E.A. ID guide

Origin and Distribution:
  • It lives in the Ponto-Caspian region (Black, Caspian, Azov Seas).
  • It is currently invasive in North America where significant and costly efforts are in place to reduce spread and impact.
  • It is also spreading within continental Europe, and is currently in Germany, the Netherlands, Romania, Russia and Ukraine.

  • Like the zebra mussel, the quagga mussel increases water clarity and decreases phytoplankton abundance. Quagga mussels also cause a reduction in zooplankton populations. Native species of Unionids can suffer as a result of the introduction of both zebra and quagga mussel.
  • This species is also an economic pest acting as a fouling organism and increasing the cost of water treatment and the cost to industries dependent on freshwater e.g. hydroelectric power stations.

Is it found in Northern Ireland?
  • It is not present in Northern Ireland.

How might it get here?
  • Fouling of boats and other machinery.
  • Ballast water.
  • Planktonic larvae may travel downstream from infested areas.

Prevent Spread:
  • Do not introduce quagga mussels to the island of Ireland.
  • Prevent fouling of boats and equipment.
  • Clean all equipment including boats before moving to new waterbodies.
  • Report all sightings.

You can help by reporting any sightings: @ the Centre for Environmental Data & Recording (CEDaR) - Or via the iRecord App.

NIEA Invasive Species Alert Poster - Quagga mussel: Download

  For further queries, you can contact the Invasive Non Native Species (INNS) Team in the Northern Ireland Environment Agency on 028 9056 9558 or Email: invasivespecies@daera-ni.gov.uk

Species Related Files:

Invasive Species Northern Ireland

Invasive Species Northern Ireland