Monday, February 23, 2026 |
Photo – Aquatic invasive species check – Courtesy Wyoming Game and Fish Department
Invasive snails have led state officials to permanently close a popular fishing spot near Alcova in Natrona County.
Last week, the Wyoming Game and Fish Department announced the closure of Jessica’s Pond, the outflow channel of the Dan Speas Fish Hatchery located roughly 20 miles southwest of Casper.
Game and Fish Casper Region Public Information Specialist Janet Milek said a New Zealand mud snail was discovered in Jessica’s Pond in 2022. The state agency drained the pond to keep the highly invasive mollusks from reaching the natural spring that feeds the Dan Speas Fish Hatchery. However, Milek said additional mud snails have since been found in the pond, prompting its permanent closure.
Milek said the state wildlife agency has no plans to reopen Jessica’s Pond. After earlier control methods failed, Milek said the agency now intends to fill in the site.
Jessica’s Pond was closed last October while Game and Fish developed a plan to address the invasive New Zealand mud snails. Despite their best efforts, the snails proved too difficult to exterminate. Given the importance of the nearby Dan Speas Fish Hatchery, Milek said the state agency made the difficult decision to backfill the pond.
Milek said New Zealand mud snails are extremely small and difficult to see. The public information specialist urged boaters to use caution when moving between bodies of water. When in doubt, call your local Game and Fish office.
When asked how the invasive mud snails reached Jessica’s Pond, Milek said the initial assumption was that they were carried in on boats transferring from the North Platte River into the popular fishing spot. However, Game and Fish now believe local wildlife introduced the snails.
Milek said invasive New Zealand mud snails can be found across Wyoming, including the Shoshone, Bighorn and North Platte Rivers. The snails are known to be plentiful in the waters around the Dan Speas Fish Hatchery. The public information specialist also said mud snails are small enough to pass through animals’ digestive tracts, allowing them to be consumed, transported and spread to new areas.
Built in 2013, Jessica’s Pond was named after the daughter of the construction company’s foreman. Milek said the outflow pond was stocked with fish from the Dan Speas Hatchery and quickly became a popular fishing spot. Despite the closure of the pond, Milek said surrounding services will remain accessible.
Wyoming Game and Fish is encouraging anglers to use Yesness Pond in Casper as an alternative fishing location. The site also features ADA-compliant trails and access points.
Anglers are also reminded to “Clean, Drain and Dry” all equipment when moving between waters in the state. Scrubbing stations for boots are located near many fishing access points. Other precautions, including seasonal inspections for watercraft entering Wyoming, are required before heading out. More information on aquatic invasive species and how to prevent infestations can be found on the Game and Fish website.
