States Wildlife
Menu

Invasive and nonnative animals in Montana

Last checked November 3, 2026 against official sources.

On this page
  1. AIS Species Identification Guide
  2. Brown Marmorated Stink Bug in Montana
  3. How to report
  4. Sources

22 nonnative animals are named on 2 official lists for Montana: “AIS Species Identification Guide” (Montana Fish, Wildlife & Parks) and “Brown Marmorated Stink Bug in Montana” (Montana State University Extension).

To report a sighting, see how to report.

Being on a list of nonnative species does not always mean an animal is harmful or established: each list below is described in its source's terms. A sighting of a listed animal is still worth reporting to the agency.

AIS Species Identification Guide

Montana Fish, Wildlife & Parks, archived copy, captured May 3, 2026. 21 animals.

Brown Marmorated Stink Bug in Montana

Montana State University Extension, undated page. 1 animal.

How to report a sighting in Montana

Boat or trailer with aquatic organisms: 1-800-TIP-MONT (1-800-847-6668). FWP main office: (406) 444-2535. Montana Fish, Wildlife & Parks

Do not try to catch or handle the animal. A photo taken from a safe distance, the place and the date help the agency.

Sources

  1. AIS Species Identification Guide. Montana Fish, Wildlife & Parks. archived copy, captured May 3, 2026; checked November 3, 2026.
    Quoted passages (21)
    “American Bullfrog Lithobates catesbeianus DETECTED in Montana”
    “Asian Clam Corbicula DETECTED in Montana”
    “Bighead Carp Hypopthalmichthys nobilis UNDETECTED in Montana”
    “Black Carp Mylopharyngodon piceus UNDETECTED in Montana”
    “Chinese Mystery Snail Cipangopaludina chinensis malleat UNDETECTED in Montana”
    “Faucet Snail Bithynia tentaculata DETECTED in Montana”
    “Fishhook Waterflea Bythotrephes longimanus UNDETECTED in Montana”
    “Grass Carp Ctenopharyngodon idella UNDETECTED in Montana”
    “New Zealand Mudsnail Potamopyrgus antipodarum DETECTED in Montana”
    “Northern Snakehead Channa argus UNDETECTED in Montana”
    “Nutria Myocastor coypus UNDETECTED in Montana”
    “Quagga Mussel Dreissena rostriformis bugensis DETECTED in Montana”
    “Red-Rim Melania Melanoides tuberculata DETECTED in Montana”
    “Round Goby Neogobius melanostomus UNDETECTED in Montana”
    “Ruffe Gymnocephalus cerna UNDETECTED in Montana”
    “Rusty Crayfish Orconectes rusticus UNDETECTED in Montana”
    “Silver Carp Hypophthalmichthys molitrix UNDETECTED in Montana”
    “Spiny Waterflea Bythotrephes longimanus UNDETECTED in Montana”
    “Tench Tinca tinca UNDETECTED in Montana”
    “Zander Sander lucioperca UNDETECTED in Montana”
    “Zebra Mussel Dreissena polymorpha DETECTED in Montana”
  2. Brown Marmorated Stink Bug in Montana. Montana State University Extension. undated page; checked November 3, 2026.
    Quoted passages (1)
    “Montana is the 47th state but not sure if it is yet established”
  3. Report a suspected AIS. Montana Fish, Wildlife & Parks. archived copy, captured May 3, 2026; checked November 3, 2026.
    Quoted passages (1)
    “If you see a boat or trailer with aquatic organisms attached to it, call 1-800-TIP-MONT (1-800-847-6668) immediately.”