Research Problem and Background:
Zebra mussels were introduced into the Detroit River-Lake St. Clair region of the Great Lakes from Europe in 1986 and have since spread rapidly throughout the Great Lakes, the St. Lawrence River, and the navigable inland waterways of the Mississippi drainage. A projected cost of $2 billion has been proposed for the control of zebra mussels over the 1990s in the Great Lakes alone, with this figure likely to rise exponentially as mussels continue to expand their range in North America.

Asiatic clams are found in 36 of the contiguous states of the United States, as well as in Hawaii and Mexico. Macrofouling by this species has been estimated to cost the power industry more than one billion dollars annually. This clam is currently found in or near many Reclamation facilities and can be used as a zebra mussel surrogate because it has similar reproductive and environmental requirements.

The Bureau of Reclamation is the largest supplier of water in the West. Virtually none of its structures were built with design consideration necessary to contend with a bio-fouler having the potential of the zebra mussel. Major problems anticipated to arise in western water facilities with the arrival of the mussel can be grouped into three categories: physical obstruction (ranging from friction or roughening to the complete blockage of water flow), chemical degradation (corrosion), and deterioration of ecosystems (food chain depletion and altered water quality). Currently, there are no known occurrences of the zebra mussel within a Reclamation facility. However, the zebra mussel is now found within Reclamation’s geographic area of responsibility. It is found in the navigable portion of the Arkansas River as far west as Tulsa, Oklahoma. This is within 90 miles of the nearest Reclamation facility. There are eight Reclamation facilities within 250 miles of the nearest infested site.

• Synthesize literature and data on zebra mussel problems from Great Lakes as they relate to potential Reclamation zebra mussel problems.
  
• Determine Reclamation facilities at high-risk for mollusk problems.
  
• Develop and adapt existing procedures for monitoring mollusks in the unique conditions of Reclamation water systems.
  
• Perform monitoring of selected high-risk Reclamation facilities.
  
• Develop management and containment plans for mollusk in high-risk Reclamation facilities.
  
• Investigate methods for excluding mobile larval and juvenile mollusks from water delivery system and pipe structures. This may be done in cooperation with the Great Plains Region and several Oklahoma water districts.
  
• Examine biocontrol techniques using native and nonnative mollusk predators.
  

Overall Outcome or Conclusions:
Literature and data on Great Lakes zebra mussel have been synthesized in relation to potential Reclamation zebra mussel problems. To date, zebra mussels have not been found infesting waters west of Oklahoma. However, two sites in Oklahoma have been labeled "at risk" because of their close proximity to the existing infested area and their trans-basin water connections. A risk assessment/action plan has been developed for one Oklahoma site and another is underway. Procedures for monitoring mollusks have been developed and adapted for Reclamation water systems and are currently in use at those Reclamation sites considered "at risk." Methods for excluding mobile larvae and juvenile mollusks from water delivery system and pipe structures have been investigated and will be reported in a Reclamation-wide zebra mussel assessment. The redear sunfish, an indigenous mollusk eater, was evaluated for potential mollusk control. Its use was determined to be insufficient to control large scale mollusk infestations. Lastly, this program is taking measures to educate the public of the potential dangers of zebra mussels potentially spreading throughout Oklahoma as well as other Western states.

Partners:
Program Analysis Office
Pacific Northwest Region
Central Arizona Water Conservation District
Sea Grant/CREES-USDA
Fish and Wildlife Service
U.S. Army Corps of Engineers
USDA Wildlife Research Center
Arbuckle Master Conservancy District, Oklahoma
McGee Creek Authority, Oklahoma
Mountain Park Master Conservancy District, Oklahoma
Central Oklahoma Master Conservancy District, Oklahoma Fort Cobb Reservoir Master Conservancy District, Oklahoma
Foss Reservoir Master Conservancy District, Oklahoma
Lugert-Altus Irrigation District, Oklahoma

Publications and/or Other Deliverables
A Laboratory Investigation of Redear Sunfish Predation of Asiatic Clams. Technical Memorandum No. 8220-96-16.

A Zebra Mussel assessment will be provided to Central Oklahoma Conservancy District by January 1999.

McGee Creek Reservoir Zebra Mussel Risk Assessment/Action Plan. Technical Memorandum No. 8220-98-16.

Reclamation Wide Zebra Mussel Assessment will be provided by May 1999.

Zebra mussel dock sign and brochure, June 1997.

Zebra Mussel Monitoring Research Program at the Bureau of Reclamation Technical Service Center -Summary of 1995 Monitoring Activities. Technical Memorandum No. 8220-96-15.

Zebra Mussel Monitoring Research Program at the Bureau of Reclamation Technical Service Center -Summary of 1996 Monitoring Activities. Technical Memorandum No. 8220-97-11.

Zebra Mussel Monitoring Research Program at the Bureau of Reclamation Technical Service Center -Summary of 1997 Monitoring Activities. Technical Memorandum No. 8220-98-04.

Zebra Mussel Summary of 1998 Activities will be provided by March 1999.