Te Mana Ora | Community and Public Health has issued a health warning after potentially toxic blue-green algae (planktonic cyanobacteria) was found in Lake Pegasus.
People should avoid the Lake and animals, particularly dogs, should not be allowed near the water until the health warning has been lifted. More information
The type of cyanobacteria that is currently present is Dolichospermum (formerly called Anabaena) which can be present as green globules floating in the water column or form surface scums or sheens.
Facts about cyanobacteria
- Cyanobacteria occur naturally but can increase rapidly during warmer months.
- Algal blooms are caused by a combination of nutrients in the water (such as nitrogen and phosphorus), and favourable weather conditions (e.g., increased temperature, calm days).
- If the water is cloudy, discoloured, or has small globules suspended in it, avoid all contact.
- Not all cyanobacterial blooms are visible to the naked eye and toxins can persist after the blooms disappear.
- Cyanobacterial concentrations can change quickly with changing environmental conditions (e.g., wind). If a health warning is in place avoid contact with the water.