Montana Fish, Wildlife & Parks said Wednesday a submerged drainpipe may have been how invasive New Zealand mudsnails entered a trout hatchery near Bridger in south central Montana.
FWP said the mudsnails may have moved through a drainpipe that over the years dipped into a nearby creek with an infestation.
In August, shortly after FWP discovered the invaders during an annual inspection, fisheries administrator Eileen Ryce told YPR the main concern was that the hatchery could spread the invasive species around to the waterbodies it stocks.
“What they tend to do is grow very dense, and they can out compete out invertebrates, which can then impact the food source of fish and other aquatic life," Ryce said.
Ryce said FWP cut off supply from the Bridger facility after it noticed the infestation. This is the first FWP-run hatchery to become infested with mud snails, according to the agency.
FWP said Wednesday roughly 20,000 pounds of fish were euthanized and it plans to make up losses with fish from other FWP hatcheries. It also says it’s working on a containment and mitigation strategy.
