What are Harmful Algae Blooms (HABs)?

What are Harmful Algae Blooms (HABs)?

Harmful Algal Bloom, Blue-Green Algae, Cyanobacteria. Whatever you call it, it’s a problem facing lake and pond owners.

Cyanobacteria are completely natural and part of the complex web of life found in fresh and saltwater ecosystems. Of the hundreds of types of cyanobacteria found in North America, only about a half dozen species are problematic in that they can produce cyanotoxins. 

Cyanotoxins are some of the most powerful toxins produced by nature. Cyanobacteria do not always release toxins, but when they do it can be devastating to a waterbody’s ecology. These cyanotoxins are capable of killing almost everything in a body of water and can be a threat even to creatures living near the water.

When these toxin producing cyanobacteria experience an explosive burst of growth it is known as a Harmful Algal Bloom, or HAB.

When conditions are right, typically during summer when water temperatures are highest, cyanobacteria begin to reproduce exponentially. In these conditions they are able to outcompete all the other forms of phytoplankton and take over small ponds or parts of larger lakes. These algal blooms can sometimes be seen as a bright green “dust” under or on the surface of the water. The explosive growth is unsustainable and eventually conditions change and the cyanobacteria begin to die or go into remission. With the ability to move up and down through the water column, a lake can be bright green one day and crystal clear the next only to have the bloom come back with a vengeance several days later.

Targeted treatment of the cyanobacteria in your lake or pond with products designed for that purpose can reduce the amount of cyanobacteria living in your lake. Care must be taken when performing this treatment as killing too much of the cyanobacteria at once can have the same negative effect on the lake or pond as a full blown HAB, resulting in a fish kill from loss of oxygen or release of the cyanotoxins. Treating the cyanobacteria is only part of the solution.

Reducing the sources of excessive nutrients getting into the body of water and keeping nutrients in a balanced range that allows other plants to grow but not allow cyanobacteria to flourish is key to long term success. It requires skill and knowledge to keep the ecosystem healthy for your fish while blocking the cyanobacteria from blooming.

This nutrient remediation process is not cheap, nor is it quick. The cutting edge management services will ideally run all spring and summer long, beginning early with site inspections, laboratory testing, nutrient source remediation, and culminating with treatment of the lake to adjust the nutrients in the water column to the correct ratio. In the end you would have a well balanced ecosystem that helps you achieve your fishery dream.

If you have concerns about HABs or any other lake or pond issues, please give our office a call and AES would be happy to set up a consultation so we can begin to address your concerns.

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