Date: 03/02/09
Contact: C. Douglas Nielsen
Phone: (702) 486-5127, ext. 3500

GO FISH BUT DON’T MOVE A MUSSEL

Go fish! But while you’re at it don’t move a mussel. That’s the request from fisheries biologists with the Nevada Department of Wildlife who are asking anglers to take the precautions necessary to prevent the spread of quagga mussels and other aquatic nuisance species (ANS) between waterways.

“An aquatic nuisance species is any nonnative species of aquatic plants or animals that has a negative effect on desirable aquatic species or on the ecological conditions of our waters,” said Jon Sjoberg, supervising fisheries biologist for NDOW. “Those negative effects can include a decrease in the numbers of sportfish and a loss of recreational fishing opportunity.”

Quagga mussels are just one example of an ANS. Others include zebra mussels, a cousin to the Quagga, and New Zealand mudsnails. The primary method of overland dispersal of these small animals is through human-related activities. Because they have the ability to attach to hard surfaces and survive out of water for several days, quagga and zebra mussels are easily transported from one waterway to another on boats, trailers, vehicles and even fishing equipment. Many infestations are the result of adult mussels hitching rides on watercraft.

A free ride on a recreational vessel is most likely the way quagga mussels were first transported from the Great Lakes region and introduced into the Lower Colorado River system. The mollusks were first discovered in Lake Mead in 2007 and subsequently have spread to waters in Arizona, California, Utah and Colorado.

Though they are an aquatic species, quagga mussels can survive in small pockets of water and are capable of enduring dry conditions for five days or longer. To stop the spread of mussels and other nuisance species, boaters and anglers are encouraged to take a few minutes and clean their boats, trailers, canoes, waders, float tubes, and other related gear before leaving one body of water and heading to another regardless of their starting point or their final destination.

The rule of thumb for cleaning boats and other equipment can be summed as in three words – clean, drain and dry. Clean the hull or trailer and remove all plant and animal materials. Drain any water from the boat, livewell and the lower unit as well as the boat trailer. And dry the vessel before moving elsewhere. If your boat has been in a body of water where quagga mussels, zebra mussels or New Zealand mudsnails have been found, keep the vessel dry and out of water for at least five days.

At first glance quagga and zebra mussels, both native to the Dneiper River drainage of Ukraine, seem rather innocuous. But get enough of them in one place and they are a real problem. Both species can colonize in numbers large enough to block water intakes and even affect municipal, agricultural and industrial water supplies such as those used in power plants. All of these problems are very costly to deal with, explained Sjoberg who referred to a University of Notre Dame study that estimates the cost at $200 million per year to the Great Lakes regional economy alone.

Quagga and zebra mussels also can affect recreational boaters by clogging water intakes and other areas on their vessel’s motor – both inside and out – which can lead to mechanical and performance problems. Handling problems can result when mussels attach themselves to equipment within the steering system.

In addition to their impact economically, quagga and zebra mussels can have a devastating effect on recreational fisheries. The mussels are prodigious filter feeders that strain zooplankton and phytoplankton from the water. Each one can filter up to one liter of water per day. A large decrease in plankton can alter the food chain in lakes and reservoirs and reduce damage both sport and native fish populations.

The Nevada Department of Wildlife (NDOW) protects, restores and manages fish and wildlife, promotes fishing, hunting, and boating safety. NDOW’s wildlife and habitat conservation efforts are primarily funded by sportsmen’s license and conservation fees and a Federal surcharge on hunting and fishing gear. Support wildlife and habitat conservation in Nevada by purchasing a hunting, fishing, or combination license. For more information, visit www.ndow.org.