Blue-green algae
Did you know, blue-green algae are not algae at all.
They are photosynthetic bacteria (also called ‘cyanobacteria’) that rely on sunlight for energy.
Blue-green algae are present in almost all aquatic ecosystems, including creeks, rivers, lakes and wetlands.
Individual cells are very small, so blue green algae can be present in a water body without being visible.
These cyanobacteria are an important part of a healthy ecosystem. They perform functions like photosynthesis, nitrogen fixation and nutrient cycling in the food chain.
Health Risks
Blooms of blue-green algae can pose significant risks to wildlife, pets, and human health by producing toxins.
Blooms also cause water discolouration, scum and odorous compounds.
Blue-green algae toxins can affect us in three main ways:
- Hepatotoxins damage the liver and may also increase the risk of certain types of cancer.
- Neurotoxins damage nerves and can cause numbness and muscle tremors
- Allergens are thought to produce a range of reactions like:
- skin rashes
- irritation of the eyes, and
- gastroenteritis.
Blue-green algal toxins are colourless, odourless, and can remain present in the water weeks after the algae have disappeared.
They are not destroyed by boiling the water.
Blue-green algae blooms
Blue-green algae can bloom quickly under the right environmental conditions. These include:
- abundant sunlight
- warm temperatures
- still water, and
- sufficient levels of nutrients (especially nitrogen and phosphorus).
Nutrients are either naturally present in sediments or wash from the surrounding catchment (agriculture, sewage effluent and stormwater run-off).
Helping prevent blue-green algae blooms
We can help prevent blue-green algal blooms by limiting the amount of nutrients in the water and promoting ecological health.
Detergents and fertilisers contain a high concentration of nitrogen and phosphorus, so we can all play our part by:
- preventing nutrients from washing into roadside drains (e.g. by washing the car on the lawn rather than on the road)
- using phosphorus-free detergents
- reducing the use of fertilisers
- helping to rehabilitate waterways, and
- preventing land erosion, where possible, to stop soil washing into waterways.
Reporting blue-green algae blooms
For any algal bloom outbreaks in ornamental or recreational lakes and reservoirs in Logan, please:
- call us on 07 3412 3412
- email us at environment@logan.qld.gov.au
To report other algal bloom outbreaks, please visit the Queensland Government website for a list of contacts.
Helpful links
You can visit the below websites for more information: