What are Algae?
Algae are photosynthetic bacteria that are important indicators of the health of an ecosystem as almost all aquatic animals are dependent on this as a primary producer of the food chain. They are an important indicator of water quality as they reflect chemical properties such as PH and nutrients.
If algae grow in large quantities, known as a bloom, they can create issues. This happens when there is an overabundance of certain nutrients, often phosphorus and nitrogen. This can negatively affect the health of organisms in the water as oxygen levels decrease. Blue green algae, or cyanobacteria, create a significant concern as they may produce toxins that can cause serious illness or death in humans and animals.
Algal blooms occur in favorable conditions:
- warmer water with abundant sunlight
- slow moving or still waters
- sufficient nutrients
- Chemical water components (pH, etc.)
Typically, algal blooms occur in Nova Scotia in late summer to early fall, however in 2021 we saw algal blooms in early spring.
Algal blooms can be many colors, from blue, red, brown and green and may smell like fresh cut grass or garbage. The blooms can look like foam, mats or scum on the water, or like pea soup or paint. If you think you have ingested blue green algae, it’s important to call the poison centre or doctor (vet for pets) as soon as possible. It is also important to notify the Department of Environment and Climate Change so it can be investigated.
How Can You Help?
As lake communities grow, we see the effect of human activity increasing occurrences of algal blooms. As environmental stewards, we can do several simple things to reduce our impact.
- Promote a native species riparian zone along the edge of the water for a minimum of 5 m/15 feet to be most effective. This helps prevent surface water runoff and filters pollutants and nutrients that can lead to blooms. A healthy riparian zone also helps to reduce temperatures along the shore and provides habitat for many species. Grass clippings from mowing too close to the shoreline is a common way excess nutrients enter the water system which can be prevented through allowing a riparian zone to grow.
- Manage stormwater and runoff using rain barrels or cisterns, as well as rain gardens designed to absorb excess water.
- Minimize the use of fertilizers, even natural ones. All fertilizers contain extremely high levels of nutrients that can promote algal blooms if allowed to get into the water.
- Manage waste effluent by ensuring proper maintenance of septic tanks and animal waste, as human and animal waste contains high levels of phosphorus and nitrogen.
- Use phosphate-free products for household cleaning and personal use.
At Helping Nature Heal, we use specific “plant recipes” of native species determined by your soil type, location and other important factors. We design stormwater management systems and rain garden to reduce the chance of pollutants and nutrients from reaching the shoreline and entering the water body.
Department of Environment and Climate Change: 1-877-936-8476
Poison centre: 1-800-565-8161 (NS)
902-470-8161 (Halifax or outside NS)