Plan in place if invasive mussels reach Keyhole

With invasive zebra mussels now known to be present nearby, the Wyoming Game & Fish Department (WGF) has developed a rapid response plan specific to Wyoming water bodies including Keyhole Reservoir.

Meanwhile, watercraft owners have been reminded to clean, drain and dry their boats before moving between bodies of water and are asked to ensure they follow all the regulations for AIS inspections.

According to Game & Fish, invasive zebra and quagga mussels have not yet been found in Wyoming. However, the South Dakota Department of Game, Fish and Parks and U.S. Bureau of Reclamation confirmed in July that zebra mussels had been found in Pactola Reservoir in Pennington County.

"We received an image of a possible zebra mussel that had been found on a pair of sunglasses while an individual was spear fishing in Pactola Reservoir," said Aquatic Invasive Species Coordinator, Tanner Davis, in a press release.

"Upon further investigation via water sampling by BOR, free-swimming zebra mussel larvae, called veligers, were found in two of the four samples collected.”

According to WGF, these mussels originate in the Black and Caspian seas, but are widespread in the United States, notably in neighboring states including Colorado and Utah. Transported in water on boats as microscopic larvae or attached to surfaces on boats as juveniles or adults, they are prolific and can completely infiltrate waters rapidly, removing nutrients from water, clog pipes and waterways, damaging boats and out-competing native mussels.

Should either type of mussel be found in Keyhole Reservoir, the rapid response plan would begin with closure of the reservoir to shore launching on the east side of Cottonwood Bay and near the dam area. Boat ramps would be closed at night and a boat exit inspection location would be set up at Paradise Foods in Pine Haven and near the State Park Headquarters on Marina Road.

All watercraft will be required to submit to an exit inspection and, if necessary, decontamination.

After the first two years of this plan being in place, night closures and exit inspections will continue to be required, but boaters that only launch on the reservoir will be able to sign up for the local boater program to speed up the inspection. The Wind Creek and Coulter Bay ramps will be closed to anyone not enrolled in this program.

According to WGF, zebra and quagga mussels have caused fisheries to collapse, have created hazards to swimmers and waders, have reduced water quality and have caused significant damage to water treatment facilities, hydroelectric power generators and irrigation systems. As Wyoming is a headwater state, it is believed these impacts would cascade down the Columbia, Colorado and Missouri river drainages.

If these mussels are detected, it does not necessarily mean they will establish themselves. According to WGF, monitoring and containment efforts will begin immediately and, if mussels are not detected again for several years, the water will be considered negative.

However, if they do establish themselves, they will likely be there to stay, as there are currently no available tools to eradicate them.