HELENA — People are asked to be on the lookout for harmful algal blooms (HABs) that can occur on Montana’s lakes and reservoirs.
The Montana Department of Public Health & Human Services (DPHHS) said in a news release that the blooms can release toxins that can harm human and animal health.
HABs can occur when certain conditions (such as nutrient pollution, sunlight and temperature) cause a rapid overgrowth of blue-green algae, also called cyanobacteria.
Blue-green algae are native organisms and commonly occur at low, safe densities in Montana’s lakes, streams and reservoirs.
Blue-green algae are often confused with green algae since both can produce overgrowths (blooms) that affect recreation, cause odor issues and reduce oxygen in the water. However, green algae do not produce harmful toxins.
How to identify a HAB:
- A coloration or scum in the water that can look like spilled paint, pea soup or grass clippings.
- Often blue, green or red in color.
Toxins can be produced at any time when a bloom is present and remain in the water even after the bloom has visually dissipated. Toxins in the water may cause irritation of the skin and eyes upon contact; irritation of the respiratory system if water droplets are inhaled; and headache, nausea and vomiting if ingested. Pets and livestock can become severely ill and even die if they ingest the toxins. HABs do not always release toxins.
Click here to report suspected HABs to help alert others and prevent illness.
DPHHS says if the water shows signs of a HAB, do not drink, swallow, or swim in the water and keep children, pets and livestock out. Rinse off with tap water immediately if you think you or a pet has come in contact with a HAB.
If you suspect a HAB-related illness in a person or animal, call your health care provider or veterinarian, or if it is an emergency, call Poison Control immediately at 1-800-222-1222.
Nutrients such as nitrogen and phosphorus fuel algae growth and potential HABs. Actions you can take to reduce nutrient pollution in Montana’s waters include:
- Reduce your use of lawn or crop fertilizers.
- Landscape with native plants that don’t need fertilizers.
- If you live alongside a stream or lake, restore and protect native woody vegetation, plants and grasses because they help filter pollution and stabilize land.
- If your home relies on a septic system, have it regularly serviced and consider upgrading it to a higher-level treatment system.
Recreationalists can check the DPHHS website to view the map of reported blooms, health advisories, information associated with reports and information on how to identify a HAB.
