The threat of an introduction of invasive aquatic species into LAK Reservoir near Newcastle is resulting in changes to recreational access at the site.
As of April 1, 2023, motorized watercraft (including watercraft with electric motors) are not allowed on LAK Reservoir. Non-motorized watercraft that are hand-launched will still be allowed. In addition to these watercraft, the reservoir will remain open to anglers for shore and ice fishing.
“Due to the discovery of invasive zebra mussels in Pactola Reservoir in South Dakota’s Black Hills in summer 2022, the threat of these invasive species getting introduced into a Wyoming water has been significantly increased,” said Sheridan Region Fisheries Supervisor Paul Mavrakis. “In discussions with True Ranches, it was decided that eliminating motorized watercraft on the reservoir would be an effective way to help reduce the AIS threat to LAK while still providing angling access.”
To protect LAK and other Wyoming waters, all watercraft traveling into Wyoming from out of state between March 1-Nov. 30 must be inspected prior to launching on a Wyoming water. In addition, any watercraft that has been in a water infested with zebra/quagga mussels within the last 30 days, is required to undergo a mandatory inspection by an authorized inspector prior to launching in Wyoming during ALL months of the year. To expedite this process for watercraft owners coming into northeast Wyoming, a new AIS watercraft inspection station opened in Newcastle this year at the Gateway Travel Center at the junction of U.S. Highways 16 and 85. It is open seven days a week.
Resident and nonresident watercraft owners must also purchase and display a valid AIS decal. Only non-motorized inflatable watercraft 10 feet or less in length, solid and inflatable paddleboards regardless of length, and devices defined as water sport toys are exempt from the decal requirement.
LAK Reservoir is privately owned by True Ranches. Public access to it is provided by an access agreement between the ranch and the Wyoming Game and Fish Department. The reservoir is a popular fishery offering anglers the opportunity to catch walleye, smallmouth bass, tiger musky and other warm water species. The reservoir primarily serves as an irrigation reservoir for True Ranches properties.
Zebra mussels reproduce exponentially when they become established, which could negatively impact the fishery and damage the water infrastructure the ranch relies on to irrigate their hayfields. In their juvenile stage they can spread easily from just a little water left standing inside a watercraft. Adult mussels spread easily as they can attach to hard surfaces and live up to 30 days out of the water.
LAK Reservoir is not the only Wyoming water facing the threat of an AIS introduction. It is important that all boaters and anglers take steps to prevent moving zebra mussels or other invasive plant and animal species. Cleaning, draining and drying watercraft and equipment between waters is the most effective way to prevent moving AIS to new locations.
