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Algae Blooms
Green Algae
- Typically light green to grass green
- Colour can vary depending on the age of the algae
- Found attached to surfaces of rocks and aquatic plants, floating in the water column or on the surface of the water
- Often have hair like strands that can be found in clumps giving a cotton candy appearance while floating in the water
Blue-green Algae
- Typically a blue-green to green pea soup in colour
- It will appear as though someone has spilled paint on the surface of the water or in small green dots or globs
- Float within the water column and you may observe it is present only during a certain times of the day
- Some of these blooms can produce toxins that can make people and animals sick; so it is important to understand what blue green algae looks like as use of the water should be avoided until the bloom is gone
- If you notice a blue green algae bloom please call the Ministry of Environment and Climate Change’s Spills Action Center 1-800-268-6060.
Algae or something else?
- Algae do not have roots, stems or leaves while aquatic plants do.
- Pollen will most often appear in a yellow colour where a blue green algal bloom will be a pea green to blue green colour. Pollen occurs in spring and early summer and blue green algae are more likely to bloom in late summer to early fall.
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Report any details about how it was growing, colour, odour, and substrate (in water, sand, rock, wood, vascular plants).