Monitoring carried out by Environment Southland shows there are still high levels of the toxic algae planktonic cyanobacteria in the Waituna Lagoon.
With duck shooting season opening this weekend, Environment Southland’s director of science and information Graham Sevicke-Jones said those hunting ducks need to avoid contact with the water.
“The kind of cyanobacteria found in Waituna Lagoon is planktonic, the lake kind. While it can appear as greenish globules in the water, or a greenish tinge, in this case it’s not visible and that’s just the nature of this algae. Just because you can’t see it doesn’t mean it isn’t there.”
Planktonic cyanobacteria (floating or suspended algae) is different to that found in rivers during warmer months, but can still produce toxins that can be harmful to people and animals if swallowed, or through contact with skin.
The most likely symptoms are skin rashes and blisters, but can include tummy pain and nausea. People would normally have symptoms within 12 hours of contact with the water.
If you experience health symptoms, visit a doctor immediately. Dogs that consume cyanobacteria should be taken to a vet immediately.
Southern DHB medical officer of health Dr Keith Reid advised caution when consuming any ducks harvested from the lagoon.
“There is still much research to be done around cyanobacteria, and this is an area where we need more information. However, what we do know is there will be a level of risk to those who consume ducks or fish from waterways with toxic algal blooms.”
Dr Reid advised that consumption should be limited to less than one meal a week, and that the liver should be avoided, as this is where toxins accumulate in the duck’s body.
Fish and Game field officer Erin Garrick said there are 50-100 hunters that hunt on Waituna Lagoon over opening weekend.
“Many of these hunters will be using their dogs to retrieve the ducks, so it is essential that these hunters are aware of the current risks associated with the lagoon as mentioned by both Environment Southland and Public Health South.”
Environment Southland monitors for toxic algae at various river and lake sites across Southland, however toxic algae can occur anywhere. Learn what to look out for at www.es.govt.nz/toxic-algae.