Non-Native Species Pose a Grave Threat to Colorado's Ecosystem

Colorado's pristine ecosystem is under threat as non-native species continue to invade the state's waterways.

Recent discoveries of zebra mussels and rusty crayfish have sparked concern among Colorado Parks and Wildlife (CPW) officials, who are taking drastic measures to protect the state's delicate ecological balance.

On Thursday, CPW announced plans to eradicate zebra mussels from Highline Lake State Park, located near Grand Junction. The lake will undergo chemical treatment and will be emptied of all water by 2024 to remove the invasive species. This move comes after multiple zebra mussels were found in the lake, including five just last week.

Five adult zebra mussels were found on the bottom of buoys located throughout Highline Lake on Oct. 1. (Colorado Parks and Wildlife.)

These small but destructive creatures are known for their prolific reproductive abilities, with one female zebra mussel capable of producing over 30,000 eggs in a single reproductive cycle.

This rapid spread poses a major threat to the lake's fish population. To prevent further spread of the mussels, CPW has waived bag and possession limits, allowing anglers to keep all fish they catch from the shore.

In another alarming development, CPW reported the discovery of rusty crayfish in Lake Granby, a major reservoir that feeds into the Colorado River system.

Rusty crayfish protect their eggs in a sticky mass underneath their tails, spawning hundreds a year. (University of Wisconsin Stevens Point)

This marks the first time the invasive species, known for their voracious appetites and lack of predators, has been found in the Upper Colorado River Basin. In response, CPW has placed traps in the water and is encouraging anglers to kill any they come across.

While these measures may seem extreme, wildlife officials emphasize the significant threat posed by invasive species to Colorado's ecosystem. Rising temperatures in the state are creating an ideal environment for these non-native species to thrive, putting the native fish population at risk.

The Bureau of Reclamation has even launched a review process to explore ways to disrupt invasive species downstream from the Colorado River's Glen Canyon Dam.

ANS Sampling and Monitoring team members separating and identifying crayfish from Lake Granby during trapping efforts the week of Sept. 11. (Colorado Parks and Wildlife)

"Finding any invasive species is detrimental to our state's aquatic ecosystems, and finding rusty crayfish in Lake Granby, which feeds into the Colorado River, poses an even greater threat to the entire Colorado River Basin," said Robert Walters, CPW's invasive species program manager told the Colorado Sun.

While the fight against non-native species may seem daunting, CPW and other wildlife officials are committed to protecting Colorado's ecosystem and preserving its natural beauty for generations to come.