It turns out that single adult zebra mussel found at Highline Lake in September had company, meaning the water body is now the first in Colorado categorized as infested with the invasive species.
Alan Martinez, manager of Highline Lake State Park, said that after previous sampling found no more of the mussels, 10 adults have now been found at different locations in the lake, thanks to additional discoveries on Friday and Sunday. The discovery of multiple adults means they’re assumed to be reproducing.
“We are unfortunately the first-ever body of water infested” in the state, he said. “It’s not a title that we want. Now we’ve got to figure out how to protect the rest of Colorado.”
He said there will now be a lot of discussion within Colorado Parks and Wildlife about how to do that.
Mike Springsteel, Highline Lake State Park boat inspector and park ranger, inspects a boat for mussels before entry to the park on Friday.
MCKENZIE LANGE
“We need to figure out where we move forward at this point and right now we don’t have an answer on that,” he said.
Colorado has had intensive boat inspection and decontamination protocols in place in an attempt to keep zebra and quagga mussels out of the state. They quickly reproduce, clogging pipes and other infrastructure with their shells and posing ecological impacts as they filter out and eat plankton, threatening the aquatic food chain and fisheries.
Previously, an adult zebra or quagga mussel never had been found in the state. Larval-stage mussel “veligers” have been found in some state reservoirs or lakes in the state, but the mussels never established themselves in those water bodies.
The initial discovery in September meant Highline was in “suspect” status for zebra mussels. That meant that motorized and other trailered boats leaving Highline were to be subject to mandatory inspection, and if necessary decontamination, as a precautionary measure until three years passed without further detections of the mussels. Those inspections already were required for boats going into the lake.
Now the new protocol will remain as long as the lake is infested, and Martinez said there’s no way of getting rid of the mussels short of draining the lake.
He previously has said that doing that would mean losing a warm-water fishery there that took decades to build.
Robert Walters, Parks and Wildlife’s invasive species program manager, has said that even draining a lake doesn’t guarantee eradication.
An inspector examines a boat motor at Highline Lake.
SENTINEL FILE PHOTO
MCKENZIE LANGE/The Daily Sentinel
Martinez mentioned as another possibility preventing boating at Highline, but that’s something he doesn’t want to see happen to the Grand Valley’s go-to place for motorized boating.
But he added, “Nothing is off the table. We just have to figure out what we’re going to do.”
The lake’s seasonal closure to surface-use activities began Oct. 1, meaning that Parks and Wildlife has time to determine next steps before next year’s boating season begins.
Martinez called the infestation “the worst possible scenario,” noting that Colorado has worked hard since 2008 to keep invasive aquatic species out of the state.
Parks and Wildlife Acting Director Heather Dugan said in a news release Tuesday, “Thanks to Colorado’s robust early detection sampling and monitoring program, we were able to make this discovery. As more and more people use our water resources for boating, we must continue to work tirelessly to prevent the spread of these harmful invasive species.”
