By Montana Grant

Posted: October 3, 2019

Mud Snails, from New Zealand, have found their way into a private trout hatchery in Hamilton, Montana. These invasive species are damaging to our ecosystems.

The MT FWP has quarantined this hatchery until the snails have been removed. Private hatcheries are monitored by the state and their fish are used to stock private ponds throughout the state. Public hatcheries stock fish in only public access waters.

The snails have been traced to a hatchery in South Dakota, where the infected hatchery receives their stock. This private hatchery south of Hamilton, stocks about 100 private ponds in the region.

Mud Snails do well in cold water. Aquatic Invasive Species, AIS, are actively being prevented from entering Montana waters. Sadly, these snails are already in the Madison, Yellowstone, and Missouri Rivers.

This the first time the mud snails showed up on the west side of the continental divide, in our region. Mud snails also can be found in Idaho, Washington, Oregon, and California.

Anglers, boaters, and water recreationists must thoroughly clean and dry their boots, warders, gear, live wells, and boats/engines after each time on the water. The snails are extremely tough to kill and can survive out of water for days. They can survive for weeks in a damp environment.

Keep our waters clean!

Montana Grant

For more Montana Grant, find him at