Invasive Snail Species Found in Montana Fish Hatchery

by Taylor Cunningham
(Photo by Brian Vander Brug/Los Angeles Times via Getty Images)

Due to an invasive snail infestation, a Montana fish hatchery was forced to kill nearly all of its stock. And it’s the second time in two years that the facility has had the problem.

As Fox News reports, a collection of New Zealand mud snails made their way into the Bluewater State Fish Hatchery. The species has been a nuisance to the state since 1995 when it was found in the Madison River. And it has since spread into many Montana waters.

The New Zealand mud snail is quick to multiply and hard to kill. Because of that, it can be difficult or even impossible to eliminate once it’s established a population. And because it isn’t native to North America, it can change the ecology of water bodies.

So to deal with the problem, Bluewater had to go to extreme measures to kill the animals quickly. The staff had to destroy nearly all of the rainbow trout and largemouth bass living in the facility.

Unfortunately, this is the second time that the hatchery has had to kill its fish to stave off an infestation. In 2020, the snail led to a decontamination process that killed 20,000 pounds of trout, which equaled an $85,000 loss.

Officials believe that the pest came into the hatchery through a drain pipe submerged in a creek that year.

The source of this year’s problem is still unknown. But FWP believes that some snails may have been living inside cracks in the concrete tanks during the last decontamination. And the hideaway helped them survive.

“We are conducting a full decontamination and our oldest concrete settling basins, where this infestation was discovered, will no longer be used,” said Eileen Ryce, FWP fisheries division administrator.

This year’s infestation will cost the hatchery an estimated $225,000. The total comes from the loss of fish and the cost of killing the snails. Nearby hatcheries will help to re-stock the facility to help mitigate further hits.

Montana Hatchery Hands out Free Fish After Dealing with Invasive Snail Infestation

The staff had to kill all of the animals living inside contaminated tanks. But some rainbow trout survived. Those fish live in an interior section of the hatchery. And after searching, there was no proof that the snail had migrated.

Luckily, most of the destroyed fish are big enough to eat. So instead of wasting the animal, FWP handed them out to kids under 12 and anyone with a fishing license.

The hatchery set a limit of 5 per person. And it asked people to dispose of remains in their household garbage instead of in waterways or down the drain to ensure the snail doesn’t spread further into the state.