Montana's Response to Aquatic Invasive Mussels
Background
What are Invasive Species?
Invasive species include plants, animals, and pathogens that are non-native to our ecosystems 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.
Some invasive species are aquatic, while others, including many noxious weeds, live in terrestrial habitats.
We are fortunate that Montana remains relatively free of aquatic invasive species that have wreaked havoc in other states.
- They colonize and restrict flow in water supply pipes, thus impacting hydroelectric operations, public water supplies, power generation and other industrial facilities.
- They also foul boats leading to increased drag, docks and pilings impacting their structural integrity, and rocky shorelines leading to hazards for human recreation.
- By filtering phytoplankton and other materials suspended in the water, these species have drastically altered food webs and the composition of species in the water bodies where they have become established.
Where did Zebra and Quagga mussels come from?
Zebra and Quagga mussels are native to eastern Europe and western Asia. They were likely transported to North America in the ballast water of commercial ships.
Both species were first detected in the late 1980s in the Great Lakes region and have quickly spread across North America. This colonization across the continent has likely been assisted by barge traffic and inadvertent transfer via recreational boaters.
What impacts will invasive mussels have in Montana?
Ecological
- Altered Food Webs, Habitat Changes, Extirpation of Native Species
Economic
- Irrigation, Public Water Supplies and Sewer Returns, Hydropower, Tourism, Fishing/Boating
Recreation
- Boating, Swimming, Fishing
Public Health
- Injury (cutting hazard), Bioaccumulating Heavy Metals and Toxic Algae
Estimated potential economic damages of Dreissenid mussel infestations in Montana are up to $234 million per year, including:
$122 million to recreation
$61 million to agriculture
$47 million to infrastructure
$4 million to government revenue
Additionally, the estimated loss to lake shore property values is estimated to be $497.4 million.
See the full report or a fact sheet for more details.
Montana's Response
Early Detection
Montana’s Aquatic Invasive Species (AIS) Early Detection and Monitoring Program has been in place since 2004. Early detection allows Montana Fish, Wildlife & Parks (FWP) biologists to locate small or source AIS populations, while monitoring allows FWP to study existing population trends and investigate suspect findings.
Displayed here are AIS survey locations (gray dots) visited since 2004.
Numerous partners have assisted FWP with these efforts, including:
- Whitefish Lake Institute
- Clearwater Resource Council
- Swan Valley Connections
- Blackfoot Challenge
- Flathead Basin Commission
- Confederated Salish and Kootenai Tribes
- Blackfeet Tribe
- MT Department of Natural Resources and Conservation
- National Park Service
- U.S. Army Corps of Engineers
- U.S. Bureau of Reclamation
- U.S. Fish and Wildlife Service
- U.S. Forest Service
For the current survey year, the following surveys have been reported so far:
(click here for a mobile optimized view )
Contain and Monitor
In the fall of 2016, the Early Detection and Monitoring Program detected invasive mussel larvae in Tiber Reservoir and had a suspect detection in Canyon Ferry Lake. Invasive mussels were likely transported to Montana by watercraft previously launched in contaminated lakes or reservoirs in North America.
FWP enacted emergency restrictions and rules at both waterbodies to contain any infestations and prevent spread to other lakes or waterways. These included mandatory inspection and decontamination for all vessels and equipment leaving the reservoirs and expanded survey and monitoring efforts.
Thankfully, in the years since those detections, neither adult mussels nor additional larvae have been located in these waterbodies. Tiber Reservoir was closely monitored for 5 years and Canyon Ferry Lake for 3 years.
Both reservoirs have now been delisted as a suspect waterbody and are believed to be free of invasive mussels.
Keeping Watch
In 2004, Montana FWP started a statewide watercraft inspection program. All watercraft are required by law to stop. The goals of this effort are to:
- Catch AIS entering or moving around the state, thus preventing invasive species from contaminating local waterbodies
- Educate boaters about the need to Clean, Drain, and Dry
Current AIS Watercraft Inspection Stations are shown on this map.
From 2005-2024, these efforts resulted in over 1,100,000 watercraft inspections and stopped more than 330 watercraft carrying invasive mussels.
Thousands of additional watercraft with AIS species (mostly plants) were also intercepted and decontaminated.
See Reports for details.
For the current year, the following inspections and results have been reported so far:
(click here for a mobile optimized view )
Public Awareness
For over a decade, the State of Montana has initiated multiple campaigns to educate water users about the risks of aquatic invasive species and what individuals can do to minimize risk to Montana's waters.
FWP's AIS website, shown here, is one example of the various resources available to the public and professionals.
Rapid Response Guidelines
Montana has developed rapid response guidelines for invasive mussel detections. Prevention and rapid response are the best tools for managing the risk of invasive mussels, as they are usually impossible to eradicate after becoming established.
As part of the rapid response guidelines, Montana may choose to initiate an Incident Command System (ICS). This emergency response framework allows for the efficient inter-agency action and communication to resolve a potential mussel establishment.
Montana's response to the threat of invasive mussels has been 'all hands on deck' for many around the state. But we now have many tools in place to protect Montana's aquatic resources to the best of our abilities.
We can now:
- detect mussels or other aquatic invasives early on and enact our rapid response plan, potentially eradicating populations before they become established
- contain and monitor potentially impacted waterbodies to prevent spread where eradication may not be possible
- stop invasives before they make it to new habitats with watercraft inspection
- educate the public effectively and efficiently about these threats and enlist their help to watch out for invasive species
What You Can Do
More Information:
A Greater State of Knowledge
