Quagga Mussel

Quagga mussels were found in the Snake River in September 2023. Immediately afterwards, Idaho Fish and Game assisted the Department of Agriculture in their evaluation of potential treatments to eliminate the mussels, and Idaho Fish and Game quantified the fish populations found in the six-mile stretch of river where the mussels were found, and where the treatment would occur. Biologists quickly learned that the treatment caused high mortality in certain species, while others survived quite well.

Montana’s first mussel-fouled watercraft of the year was intercepted at the Anaconda watercraft inspection station on March 10.

All watercraft entering the state of Montana with the intent of being launched into any body of water are required to be inspected, including kayaks, canoes, rafts and paddleboards. These inspections are required by law, and failure to comply may result in a fine of up to $500. Learn more how Protect Montana Waters from Aquatic Invasive Species.

Quagga and zebra mussels have spread rapidly across the country since they were first discovered in the late 1980s and, according to U.S. Army Corps of Engineers officials, have spread to every major river basin in the U.S. except the Columbia River Basin in the northwest. The mussels typically are spread by recreational watercraft such as boats, canoes, and Jet Skis that have been in infested waters. Once established in a water body, the mussel species are extremely difficult to eradicate because they have no natural predators in the U.S. and rapidly reproduce.

GAO was asked to examine efforts the Corps has undertaken to prevent the spread of aquatic invasive species into the Columbia River Basin by recreational watercrafts. This report [PDF, 3.24 MB] provides information on the Corps' Watercraft Inspection and Decontamination Program and its role in helping to prevent the introduction or spread of quagga and zebra mussels—the aquatic invasive species of greatest concern to the Corps—as well as program challenges and opportunities for improvement.

The Idaho Department of Agriculture (ISDA) has confirmed the presence of quagga mussel in the Mid-Snake River. Quagga mussel larvae was first detected in the Snake River near Twin Falls on September 18, 2023, by routine monitoring conducted by the ISDA. If nothing were done, quagga mussels would quickly take over waterways. They would irreparably harm water use in Idaho. These findings mark the first time a rapid response plan has been put into action for quagga mussels in Idaho.
See also: ISDA Confirms Quagga Mussel Larvae in the Snake River (Sep 19, 2023)

The Texas Parks and Wildlife Department (TPWD) reports that invasive quagga mussels have been detected for the first time in Texas. The quagga mussel discovery was made by National Park Service (NPS) staff at the International Amistad Reservoir in the Rio Grande basin along the Texas-Mexico border near Del Rio. Quagga mussels are a close relative of the zebra mussel, which has invaded 33 Texas lakes across six river basins since it was first introduced in Texas in Lake Texoma in 2009. In addition to being the first detection of quagga mussels in Texas waters, this is also the first finding of any invasive mussel species in the Rio Grande basin.

TPWD and partners monitor for invasive mussels in Texas lakes, but anyone who finds them in lakes where they haven’t been found before should report them immediately by emailing photos and location information to AquaticInvasives@tpwd.texas.gov.

The Western Regional Panel prepared Quagga and Zebra Mussel Action Plan 2.0 to inform ongoing management and partnership efforts intended to minimize the spread and impacts from zebra and quagga mussels in the western United States. The original QZAP action items have guided prevention, containment, research, and management to address the ecological and economic impacts of invasive quagga and zebra mussels since 2009. The purpose of QZAP 2.0 is to provide a systematic and unified approach to prevent the spread of zebra and quagga mussels into and within the western United States in the future. The urgency and the need for such a coordinated approach remain as important today as ever before. Newly infested waters, increased boating pressure, and gained public and political awareness drove the need for the Western Regional Panel to acknowledge and learn from the past and set forth a new collective path towards the future. These recommendations are intended to inform decision-making to provide increased capacity and clear direction that empowers the further implementation of a collaborative and coordinated multi-jurisdictional regional strategy to prevent the spread of quagga and zebra mussels in the West. For more resources, see: Key Documents

A geonarrative by USGS and Geoplatform.gov examining the spread of invasive mussels in the American West.

See also: Geonarratives for all USGS geonarrative / story map resources