A 12 months after Colorado Parks and Wildlife workers first found invasive zebra mussels at Highline Lake — a reservoir north of Loma, close to the Utah border — they discovered much more whereas doing routine work to take away buoys from the water this month in preparation for winter.
The primary grownup zebra mussel was discovered within the reservoir on Sept. 14, 2022, whereas workers had been routinely testing for aquatic nuisance species within the lake, Parks and Wildlife officers discovered virtually a dozen extra mussels there the following month.
5 extra grownup zebra mussels had been discovered Oct. 1 on the underside of buoys.
Wildlife officers stated the invention was troubling, although not stunning. The company has been working for 15 years to maintain the state freed from the nuisance species that may trigger tens of millions of {dollars} of injury to water distribution techniques.
“Eradicating invasive mussels is extraordinarily tough, which is why we focus so closely on stopping their introduction,” stated Robert Walters, Colorado Parks and Wildlife’s invasive species program supervisor.
“Whereas that is disappointing, we aren’t contemplating this primary try a failure,” he stated. “We consider if we had achieved nothing we’d be taking a look at a a lot bigger infestation right now with fewer choices for eradication and a higher probability of zebra mussels spreading to different our bodies of water in Colorado.”
Colorado Parks and Wildlife workers are at present evaluating choices to eradicate the mussels at Highline Lake and cease the unfold into different our bodies of water in Colorado. All the choices could have important impacts on fishing, boating and different water-based leisure actions on the lake.
Colorado Parks and Wildlife officers might probably decrease or drain Highline Lake in 2024.
“Highline is crammed by a canal system that’s related to the Colorado River, so there can be a whole lot of shifting elements to that,” stated Rachael Gonzales, northwest area public info officer for Colorado Parks and Wildlife.
Extra work to comprise and cut back the mussels’ unfold is scheduled for Oct. 12. It would embody eradicating boat docks and two Colorado Parks and Wildlife boats for inspection and decontamination, CPW workers stated in a information launch Friday.
The plan to eradicate and comprise the mussels will hurt the lake’s fishery by killing some or the entire fish there, Gonzales stated, so beginning Monday, an emergency fish salvage is in place at Highline Lake. Which means that till additional discover anglers can catch and preserve as many fish as they need, so long as they’re fishing legally.
“It’s solely shoreline fishing, to allow them to’t deliver boats into the lake, they will’t use nets and they should have fishing licenses,” she stated. “But when they catch 25 fish, they will take them. They usually should guarantee that they’re useless earlier than they go away Highline, which is a part of the rules. We’re making an attempt to offer anglers a chance to place the fish to good use.”
This fish salvage is just in impact at Highline Lake. All catch limits stay in impact at close by Mack Mesa Lake, Gonzales stated.
Anglers and waterfowl hunters are reminded to wash, drain and dry their gear earlier than touring to and coming into any new physique of water to cease the unfold of the mussels and different nuisance species, CPW workers stated.
Tiny organisms with huge, costly impacts
On Sept. 14, 2022, a single grownup zebra mussel was found throughout routine invasive species sampling. It was clinging to a sq. piece of plastic connected to a rope inserted into the underside of the lake. Extra zebra mussels had been found on docks and boats.
The invention of extra mussels prompted Colorado Parks and Wildlife to vary the standing of Highline Lake to “infested” from “suspect.” This was the primary time a Colorado physique of water was categorized as infested with zebra mussels, CPW workers stated.
In November, Highline Lake started a two-phase strategy to eradicate the zebra mussels by decreasing the lake by 25 to 30 toes to reveal areas alongside and close to the shoreline and lake mattress to kill zebra mussels by drying and freezing them.
In March, Colorado Parks and Wildlife utilized three therapies of EarthTech QZ, a copper-based molluscicide, to the lake, they stated. The compounds which are poisonous to zebra mussels, resembling Earthtec QZ, are poisonous to different aquatic organisms, which makes eliminating the zebra mussels whereas preserving the opposite species within the water difficult, Roberts stated.
The brand new infestation might result in tens of millions of {dollars} in harm to water-based infrastructure, and may threaten water high quality and restrict leisure alternative, Roberts stated final 12 months after the primary few mussels had been discovered.
A single mussel can produce as much as 1 million infants a 12 months, making it difficult to comprise the species, and almost unimaginable to eradicate them as soon as they’re launched, he stated.
The aquatic nuisances connect to strong or semisolid surfaces and clog boat engines or distribution pipes at water therapy amenities. If knocked off, the mussels can drop into and infest a physique of water, he added.
The mussels can dwell outdoors of water for 27 days underneath the proper circumstances, and may go virtually a liter of water by means of their shells every day, consuming vitamins wanted by different fish and vegetation within the ecosystem, Roberts stated.
Their excessive ranges of filter feeding may alter meals sources in lakes and reservoirs.
“The problem with eradicating zebra mussels is complicated,” Roberts stated. “You’re concentrating on small organisms in giant our bodies of water. The adults desire areas which are tough to achieve. They’re extraordinarily prolific reproducers and even lacking a small variety of them in a therapy can lead to a re-infestation.”
