Aquatic Invasive Species

Identification and Distribution

Tench Distribution Map (USGS) Tench Map. This invasive fish was introduced into Idaho in 1880s and would compete with native cyprinids and game fish in Montana.

The map's red shading shows the Tench's proximity to Montana.

Aquatic Invasive Species are also called "nuisance species."

Report a Suspect AIS

If you suspect a new infestation of an invasive plant or animal, save a specimen and complete the following form:


AIS Outdoor Report - Aquatic Invasive Species are organisms that are brought into Montana from other places. They can kill fish and jam community water supplies. In this Outdoor Report, Mike Gurnett shows us three easy steps to help stop these invaders in their tracks.

Contact Us

For more information, contact FWP at (406) 444-2449.

Photo from Montana Outdoors article

Keeping the Invaders at Bay

Montana is listening to warnings about Asian carp, VHS virus, Eurasian watermilfoil, and other aquatic invasive species (AIS). The water-borne invaders take over lake and river ecosystems, kill native fish, and ruin recreational and industrial equipment [Full Story]

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