Colorado parks authorities are moving forward with their radical plan to completely rid a lake of zebra mussels.
Zebra mussels are a species of invasive freshwater mollusk that have infested lakes across the United States. They are considered an expensive pest due to their habit of fouling water intake systems and other infrastructure.
Last month, Colorado Parks and Wildlife announced its intention to annihilate zebra mussels at Highline Lake State Park near Grand Junction by poisoning the mussels and then completely draining the lake. It’s the agency’s second attempt to rid this state park’s namesake lake of zebra mussels.
The scheme has now entered its first phase.
Last week, CPW closed the lake to all fishing as it applies EarthTec QZ, a “copper-based molluscicide,” to the lake, officials said. CPW says it’s necessary to ban fishing while the molluscicide is being applied as the copper used in the chemical designed to kill zebra mussels can accumulate in fish, posing a risk to anyone who might eat them.
CPW clarified that the fishing ban only covers the lake itself. “This action only pertains to Highline Lake. All existing regulations on Mack Mesa, Mack Wash, and surrounding bodies of water remain in effect,” the agency said in a release.
Dumping molluscicide into the lake is only the first step.
Next, CPW says it will gradually drain Highline Lake until it is completely dry by the end of next year. The agency believes that the move will kill all remaining zebra mussels in Highline Lake, but it will also kill all the fish.
Responding to an inquiry by Public Parks, CPW public information officer Rachael Gonzales confirmed that there are no plans in place to save Highline Lake’s fish population. She said CPW learned the hard way that eradicating the zebra mussels in the lake while protecting the lake’s fish isn’t possible.
“During our first attempt to eradicate zebra mussels from the lake, our goal was to not only eradicate the mussels but also save the fishery,” Gonzales said. “Our goal is and will remain to eradicate zebra mussels, and we now know that both are not feasible.” She added that zebra mussels can attach themselves to or inside fish, meaning that there is a risk of the invasive critters surviving should the fish be temporarily removed.
Gonzales said CPW is cooperating with the US Fish and Wildlife Service in its plan to drain Highline Lake. The man-made reservoir is not home to any endangered species, she clarified.
“There are no known threatened or endangered species that call Highline Lake home,” Gonzales said. “CPW has consulted with US Fish and Wildlife Service as Highline Lake eventually feeds into the Colorado River.”
Close to the border with Utah, CPW describes Colorado’s Highline Lake State Park as “an oasis in the desert.” Aside from recreational boating and fishing, the park also boasts leisurely hiking trails, mountain biking trails, and camping. The Audubon Society recognizes Highline Lake State Park as an attractive birding destination.
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Park Info
Park Name:
Highline Lake State Park
Location:
Colorado, USA
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