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“It just goes to show ya, it’s always something — if it’s not one thing, it’s another.”

“Rosanne  Roseannadanna ” on Saturday Night Live*

We’ve had a pandemic, a supply chain crisis, war in Ukraine, election jitters, and now the dreaded zebra mussel that has become the scourge of Midwest lakes and rivers, has arrived in Colorado.

Colorado Parks and Wildlife (CPW) has begun lowering water levels in Highline Lake about 20 miles west of Denver near Loma, to inspect the inlet for Zebra mussels. According to CPW, the discovery of additional invasive mussels in the water is indicative of an established population in the reservoir and has prompted CPW to change the status of the body of water from “Suspect” to “Infested.”

Zebra mussels attached to a rock show how quickly they can clog an inlet. Courtesy photo.

CPW announced this week that the lowering of the lake will impact waterfowl hunting, with blinds located on the north end of the lake becoming un-huntable around the third week of December, and possibly sooner.

“We are thankful for the continued patience and support of our visitors since we first discovered zebra mussels at Highline,” said Highline Lake State Park Manager Alan Martinez. “Now that the lake is closed to boating and the canals that feed Highline Lake have been turned off, we felt this was the best time to complete this inspection project.”

Waterfowl hunters are encouraged to call Highline Lake State Park for current conditions at 970-858-7208.

CPW staff first discovered the presence of invasive zebra mussels at Highline Lake State Park on an artificial PVC substrate in the lake during routine invasive species sampling on Sept. 14. In October, during increased testing by CPW staff additional adult zebra mussels were found in Highline Lake.

Zebra mussels are an invasive species in the United States. They are a fingernail-sized mollusk that is native to fresh waters in Eurasia. Their name comes from the dark, zig-zagged stripes on each shell. They are armed with rootlike threads of protein, called “byssal threads,” that allow them to firmly attach themselves to hard surfaces such as rocks, native mussels, docks, or boats.

Once attached — they are difficult to remove, and if they adhere to boat surfaces that are pulled from lake to lake or river within the state, or are in the water being moved, humans become part of the spreading invasive process.

Prevention is the best way to keep a water body clean of zebra mussels. But now that they are here in Colorado, the challenge is to keep them out of our critical waterways. Zebra mussels rob food from native species that feed on plankton, make a mess of docks and boats, and can literally clog water channels.

This is the first time a body of water has been categorized as infested with zebra mussels in the state of Colorado. The discovery is an alert for water managers, fishermen, and recreationists to be on the lookout for a striped invader and to be careful not to be a human carrier.

*The late Gilda Radner played the character of Roseanne Roseannadanna” on Saturday Night Live