LAS VEGAS - June 24, 2009 - Just two years after invasive quagga mussels were first detected in Lake Mead, UNLV scientists estimate that nearly 3 trillion adult and juvenile mussels currently exist in the lake's Boulder Basin alone. The mussels clog water pipelines, attach to boats and lake structures and profoundly impact the lake's ecosystem.

In an effort to lessen the impact of the rapidly reproducing species on Lake Mead, UNLV researchers, the National Park Service and multiple agency partners coordinated on the development of the first standardized quagga mussel monitoring plan to track mussel size, abundance and distribution at more than 50 sampling sites throughout the lake. The plan will be implemented by lake managers and participating agencies later this summer.

According to UNLV Research Assistant Professor David Wong, strategic monitoring will help lake managers better understand quagga mussel populations and the adverse impact they have on the lake, and allow for better coordination of remediation strategies among partnering agencies.

"In a large ecosystem like Lake Mead, it's impossible to fully eradicate quagga mussels," said Wong. "Strategically monitoring quagga mussels, however, will help us identify how they behave given the lake's unique temperature, food sources and existing biodiversity. We can then develop appropriate ways to minimize their substantial environmental and monetary impact."

The sampling sites for adult and juvenile mussels will correspond to the lake floor's rocky, sandy and muddy surfaces. Samples will be collected and analyzed at three month intervals and logged into a standardized tracking database. The database will provide a clearer estimation of the mussel invasion in Lake Mead and can also be used by water managers throughout the west facing similar situations. The monitoring plan also incorporates tracking strategies for quagga mussel larvae, known as veligers.

The discovery of quagga mussels in Lake Mead in January 2007 was the first known occurrence of the species in the western United States. Unlike the introduction of mussels in the Great Lakes in the late 1980s, the invasive species' hold on Lake Mead is more troubling due to warmer water temperatures that allow for year-round reproduction. Annual costs for maintenance of water intakes, marine structures and watercraft exceed $1 million.

In addition to Wong, the UNLV research team includes Shawn Gerstenberger, professor of environmental and occupational health; Craig Palmer, research professor for the Harry Reid Center for Environmental Studies; Jennell Miller, program coordinator for the UNLV Public Lands Institute; and graduate research assistants Sarah Mueting and Eric Loomis. Agencies involved in the creation and implementation of the monitoring plan include the National Park Service (Lake Mead National Recreation Area), Bureau of Reclamation, Southern Nevada Water Authority, Nevada Department of Wildlife, Clean Water Coalition, U.S. Geological Survey and the U.S. Fish and Wildlife Service.