Harmful Algal Bloom (HAB)

Blue-Green Algae Heading

Waterfowl Hunters Cautioned about Blue-green Algae

The Kansas Department of Health and Environment (KDHE) and the Kansas Department of Wildlife, Parks and Tourism (KDWPT) urge waterfowl hunters who use dogs to be vigilant for the presence of harmful blue-green algae. Dogs that swim in or drink water affected by a harmful algae bloom (HAB) or eat dried algae along the shore may become seriously ill or die.

Blue-green algae are really a type of bacteria called "cyanobacteria," which occurs naturally in all of our waters. Under the right conditions, the algae can rapidly increase (bloom) and produce toxins. HABs typically begin in May and can occur through October or later. Dead algae can wash up on shorelines and in marshy areas posing a risk to dogs that eat the algae or ingest it while licking their fur. A HAB may look like foam, scum or paint floating on the water and be colored blue, bright green, brown or red. Blooms can develop rapidly; if the water appears suspicious or there is decaying algae on the shore, avoid contact and keep dogs away.

Dogs are usually exposed to the toxins by drinking the HAB-affected water but may be exposed if they walk on, roll in or eat decaying algae along the shore or retrieve a bird with algae on its feathers. The signs of illness in dogs usually occur within 30 minutes of exposure and include vomiting, diarrhea, lethargy, convulsions, difficulty breathing and general weakness. If your dog has ingested algae, or has any of these signs after exposure, contact your veterinarian immediately as HAB poisoning can quickly lead to death.

People may also become ill after contact with a HAB. Symptoms vary depending upon the type of exposure (e.g. direct contact, ingestion, inhalation) but can include rash, vomiting, diarrhea, fever, sore throat, and headache. If you, or your dog, come into contact with algae rinse the area with clean, fresh water immediately.

What are blue-green algae?

Blue-green algae can be considered as simple aquatic plants that exist naturally in marine waters, rivers, lakes, and ponds. Despite their name, blue-green algae are actually types of bacteria known as Cyanobacteria. When certain conditions are present, such as high nutrient and light levels, these organisms can reproduce rapidly. This dense growth of algae is called a bloom. Some of these blooms are harmless, but when the blooming organisms contain toxins, other noxious chemicals, pathogens, or other impacts to recreation or economic activities, it is known as a harmful algal bloom.

What does a typical blue-green

algae bloom look like?

Some algae blooms can look like foam, or a thick slurry. The blooms can be blue, bright green, brown, or red and may look like paint floating on the water. Some blooms may not affect the appearance of the water.

Why should I be aware of

blue-green algae?

Some blue-green algae produce toxins that could pose a health risk to people and animals when they are exposed to them in large enough quantities, yet the mere presence of blue-green algae is not a cause for alarm. Health effects could occur when surface scums or water containing high levels of blue-green algal toxins are swallowed, through contact with the skin or when airborne droplets containing toxins are inhaled while swimming, boating, and skiing. A large percentage of the public will report "allergic" type reactions after exposure to blue-green algae, such as intestinal problems, respiratory problems, or skin irritations. Harmful Algae Blooms can appear (or disappear) rapidly. Always be mindful of any unusual look to the lake including a green or brown color, scum, or paint-like appearance and if you see what might be a bloom, please let the lake manager or other lake official know of your concerns and complete the observation form below.

What should I do if I see

a bloom?

Complete the Algal Bloom Report Form or contact us by email at HarmfulAlgae@kdheks.gov.



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