Practical information to identify and manage non-native, invasive plants and animalsThe Quiet Invasion:
A Guide to Invasive Species of the Galveston Bay Area
Human HealthThis species poses no known human health impacts.
Prohibited ListsAll species of mussel belonging to the family Dreissenidae are legally classified in Texas as exotic, harmful, or potentially harmful. No person may import, possess, sell, or place this species into state waters except as authorized by a rule or permit issued by the TPWD. A person may possess exotic harmful or potentially harmful shellfish only if the shellfish have been removed from their shells.
Introduction PathwaysThe quagga mussel was first introduced to the Great Lakes in 1989 via ballast water discharge from international shipping. Ballast water and boat hull fouling, in addition to natural dispersion, have continued to expand the quagga mussel's range in U.S. lakes and rivers (Benson et al. 2010).
Geographic DistributionThe quagga mussel is now established in the waters of 15 states in the U.S., with a high concentration in the Great Lakes. At this time, the quagga mussel is not located in Texas (Benson et al. 2010).
Specific Primary HabitatsTypically the quagga mussel will settle on hard substrates such as rocks, wood, steel, and fiberglass, and native mussels (SeaGrant 2006; ISSG 2009d). However, unlike zebra mussels, quagga mussels also thrive on muddy or sandy bottoms. D. bugensis is most often found in waters greater than 90 feet deep (SeaGrant 2006) and can tolerate temperatures from 0 to 30°C (Snyder et al. 1997).
Ecological, Economic, or Social ImpactQuagga mussel competes with native zooplankton and bottom-dwelling invertebrates for food, modifying the community structure in local ecosystems (SeaGrant 2006). The quagga mussel also impacts the operations of water and sewage treatment plants and electric power stations by encrusting pipes and screens. The species also interferes with navigation by fouling buoys, boat hulls, and docks. D. bugensis can tolerate wider environmental conditions than the related zebra mussel (D. polymorpha). The quagga mussel can also concentrate pollutants and encrust native mussels (ISSG 2009d; Benson et al. 2010).
Physical DescriptionThe quagga mussel is very similar in appearance to the zebra mussel (D. polymorpha). The shell may be a solid brown or cream color or have cream and brown stripes. Quagga mussel shells typically reach 4 cm in size and are rounded, lacking ridges (ISSG 2009d; Benson et al. 2010).
Reproduction CharacteristicsThe quagga mussel is very fecund, with females producing up to 1 million eggs per season. They reproduce via external fertilization, with spawning peaking at water temperatures greater than 20°C. Free-swimming larvae develop within a couple of days and drift for up to one month before settling on a suitable habitat (Snyder et al. 1997).
FeedingThe quagga mussel is an incredible filter feeder, removing large amounts of phytoplankton and particulate matter from the water column. Adult quagga mussels can filter more than 1 liter of water per day. The density of colonies can reach up to 100,000 mussels per square meter in some places (Snyder et al. 1997).
ControlEarly detection is key to preventing the spread and establishment of this species. Quagga mussels should not be imported or released in local waterways. If found, note the capture location and notify the TPWD. Watercraft and equipment moved from invaded water bodies should be thoroughly cleaned and inspected before being moved.
This species belongs to the following lists:
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Page Updated/Reviewed: 09/07/2010 1:45 PM |