Aquatic Invasive Species

Protect Our Waterways

Montana's lakes, rivers and streams are some of the cleanest and most beautiful in the world. Keeping harmful aquatic plants and animals out of our waters helps preserve incredible fishing, swimming and boating for everyone.

Why This Matters

  • Our lakes and rivers support world-class trout fishing and native species found nowhere else.
  • Clean water means safe drinking water and healthier ecosystems.
  • Water recreation brings millions of dollars to Montana communities every year.

How Invasive Species Spread

  • They hitchhike on boats, trailers and fishing gear.
  • Tiny mussels, plant fragments and fish eggs stick to equipment.
  • Even a drop of water can contain thousands of microscopic invaders.

The Damage They Cause

  • Zebra and quagga mussels clog water pipes, costing millions to fix.
  • Invasive plants choke waterways, making boating, swimming and fishing impossible.
  • Non-native fish outcompete native trout and other species.

Clean, Drain, Dry—Every Time

  • Clean: Remove all visible plant material, mussels, mud and debris from boats, vehicles and gear.
  • Drain: Empty all water from boats, motors, coolers and any compartments that hold water.
  • Dry: Let everything dry completely before visiting new waters.

Be a Water Steward

  • Clean all equipment between every water body, even small streams.
  • Use hot water (140°F) or high-pressure washing when available.
  • Let boats and gear dry completely between trips.
  • Never transport live fish or water between different water bodies.
  • Report suspected invasive species to Montana Fish, Wildlife and Parks.

Mandatory Watercraft Inspections

When boating in Montana, all watercraft—including motorboats, drift boats, kayaks, canoes and stand-up paddleboards—must stop at all open aquatic invasive species inspection stations. Failing to stop can result in significant fines, and inspections play a critical role in protecting Montana’s lakes and rivers from invasive species like zebra mussels.

State Resources