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Zebra and Quagga Mussels: Environmental Effects and Spread of Quagga and Zebra Mussels in Flowing Water Systems in the western U.S.

Project ID: 4442
Principal Investigator: Mark Nelson
Research Topic: Invasive Species
Priority Area Assignments: 2010 (Zebra and Quagga Mussels), 2011 (Zebra and Quagga Mussels), 2012 (Zebra and Quagga Mussels)
Funded Fiscal Years: 2010, 2011 and 2012
Keywords: None

Research Question

How do Dreissenid mussels (_Dreissena polymorpha/bugensis_) and other benthic organisms interact, and how do these interactions affect the mussel infestations in Bureau of Reclamation (Reclamation) waters?

Descriptions of these interactions are needed to understand mussel effects on community assemblages and energy flow in western U.S. freshwater ecosystems. Mussels may affect benthic communities through several mechanisms, including habitat alteration through the presence of shells, increased benthic food byproduction of pseodofaeces, and decreased food for collector filters because of competition from mussels. These ecosystem changes may impact higher organisms, including endangered fish species, through changes in food resources or alterations in their ability to consume prey items because of substrate changes. Along with negative changes in native invertebrate assemblages, there may be assemblages that are resistant to mussel invasion. Communities with high numbers of collector filterers, for example, could remove veligers from the water column and inhibit colonization. Information on the secondary spread of these organisms from invaded reservoirs is also critical to understanding pathways for invasions into downstream reservoirs. These data would provide information on potential impacts to riverine organisms and help in determining the importance of stream connections for predictions of future mussel spread and impacts.

At the present time, quagga/zebra mussels are invading lakes and rivers in the western U.S., with mussels detected in Lake Mead, the Colorado River, and reservoirs in Colorado. Mussels have also been found in irrigation canals that are used for agricultural and drinking water purposes. Information on the spread of this organism via lotic systems is needed along with baseline information on benthic invertebrates to understand potential future ecosystem impacts.

Need and Benefit

Reclamation operates numerous reservoirs and associated structures in the western U.S., which may be impacted by Dreissenid mussels. In some cases, operations depend on management guidelines that prevent adverse impacts to fisheries. Information from these studies will assist regional natural resources management staff in reducing the risk of Reclamation water facilities receiving violation notices under Federal or State laws that could negatively impact water deliveries. Information on the secondary spread of mussels in systems with multiple reservoirs would be helpful to operations and maintenance and natural resources management staff in predicting the probability of further infestations. These mussels may severely impact water delivery systems.

Contributing Partners


Research Products

Independent Peer Review

The following documents were reviewed by qualified Bureau of Reclamation employees. The findings were determined to be achieved using valid means.

Monitoring invasive quagga mussels, Dreissena rostriformis bugensis (Bivalvia:Dreissenidae), and other benthic organisms in a western US aqueduct (interim, PDF, 2.3MB)
By Fred Nibling
Publication completed on March 06, 2013

A quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897) invasion of an aqueduct in Arizona was monitored from 2007 – 2011
using colonization substrates. As numbers increased, a filtering-collector caddisfly (Smicridea fasciatella McLachlan, 1871) declined
significantly in abundance. After two years of colonization, freshwater sponges were detected and associated with a decline in D. r. bugensis
numbers. Periphyton biomass increased considerably on substrates; perhaps partially, the r
Keywords: aqueduct; canal; dreissena rostriformis bugensis; filtering-collector; freshwater sponge; quagga mussel; smicridea fasciatella

This information was last updated on April 20, 2014
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