HIGHWAY 12 WATERCRAFT INSPECTION STATION

In 2026 High Plains Conservation District partnered with Montana Fish, Wildlife, & Parks to run the Highway 12 Watercraft Inspection Station. Fish, Wildlife, & Parks aquatic invasive species program helps protect Montana’s water from invasive plants and mussels that may enter Montana from surrounding states. Stations are operating throughout Montana to inspect boats, decontaminate boats, and educate boaters on how they can prevent the spread of aquatic invasive species.

The Highway 12 Station is open 6 am - 8:30 pm, 7 days a week, from April 25th - October 19th. If you are traveling through the area, or you are a boater, stop by and chat with our staff to learn more!

WHAT ARE AQUATIC INVASIVE SPECIES?

Aquatic invasive species include plants, animals, and pathogens that are non-native to our waters and cause harm to natural and cultural resources, the economy, and human health. Invasive species often reproduce and spread rapidly due to a lack of predators or competitors to keep their populations in check.

Common aquatic invasive species:

New Zealand Mudsnail
- First found in Montana in 1995 the Madison River, it has since spread
- It has reached very high densities (300,000/m²) and at such densities can have significant impacts to ecology of areas it is introduced into
- Reproduces asexually thus it only takes one to start a new population
- Size: adults can reach up to ~ 0.15-0.25 inches in length
- Shell if right-handed coiling, elongated with 7-8 whorls separated by deep grooves.
- Shell colors vary from gray and dark brown to light brown.
Quagga Mussel
- Both Zebra and Quagga mussels have byssal threads which allow them to attach to surfaces.
- There are not native mussels in Montana that can attach to things.
- They are not generally found in lakes near shore in shallow water due to wave action.
- The quagga mussel can inhabit both hard and soft substrates, including sand and mud, down to depths of 130 m and possibly deeper.
- Prodigious water filterers, removing substantial amounts of phytoplankton and suspended particulate from the water.
- Their impacts are similar to those of the zebra mussel.
- By removing the phytoplankton, they decrease the food source for zooplankton, therefore altering the food web.
- Reaching sizes up to 4 cm
- Color patterns vary widely with black, cream, or white bands
- They usually have dark concentric rings on the shell and are paler in color near the hinge
Zebra Mussel
- Both Zebra and Quagga mussels have byssal threads which allow them to attach to surfaces.
- There are not native mussels in Montana that can attach to things.
- If you see a mussel attached to a surface in Montana either in the wild or on a boat (especially if coming from freshwater) report it to FWP.
Curlyleaf Pondweed
- Native to Europe and Asia
- Perennial, rooted, submerged aquatic vascular plant native to Eurasia, Africa and Australia
- Forms dense mats which interfere with recreation and limit the growth of native aquatic plants
- Tolerates low light and may grow in deep water Identification
- Leaves are alternate, wide, translucent, finely toothed and have noticeably curly or wavy margins (resemble lasagna noodles) and are 1.5-4” long and up to ½” wide
Eurasian Watermilfoil
- Native to Europe, Asia, and northern Africa
- Submersed, perennial, aquatic plan with feathery leaves arranged in whorls around the stem.
- Grows thick mats in waters less than 15 deep but can grow in water to 25 feet deep or more.
- Spreads by fragmentation and overland via transport on boats, motors, trailers, fishing nets, and other gear
- Can quickly take over shallow lakes and rivers, which can prevent boating, fishing, hunting, and swimming Identification
- Milfoil stems branch several times near the water surface.
- Erect stalks emerge above water with small reddish flowers.
- Typically 4, but sometimes 3-5 leaves, form a whorl around the stem.
- Each leaf has 12 or more pares of leaflets.
- Tops often turn red in color.