The potentially toxic blue-green algae cyanobacteria has been collected from the Tomahawk Lagoon in Dunedin, prompting a warning from the Otago Regional Council.

People are advised to avoid contact with the waters of the lagoon in the meantime and to keep dogs away.Testing of a water sample taken from the lagoon yesterday by the ORC indicates the presence of high levels of the bacteria.

Signs have been put up to warn the public of the risks associated with the algal bloom. Anyone experiencing health symptoms after contact with contaminated water should visit their doctor without delay.

Dogs coming into contact with the cyanobacteria should be hosed down in the first instance to remove it from their skin, and a veterinarian contacted should their condition worsen. The ORC will continue to monitor and update the public as the bloom changes.