A potentially toxic algae is spreading in a Southland lagoon.
Waituna Lagoon Photo: Flickr / Department of Conservation / Creative Commons Attribution 2.0 Generic
Southland Regional Council is warning it has found high concentrations of the blue-green algae planktonic cyanobacteria in Waituna Lagoon on the southern coast.
The council said the floating algae can produce toxins harmful to people and animals.
It is not the first time high levels of the algae have been found in the lagoon.