1. Check online before you go
There are several websites you can check that monitor water quality and potentially harmful algal blooms around the country. The Land Air Water Aotearoa(external link) website regularly monitors lake, river and beach water quality. Jump online before you hit the water to see where it’s safe to swim, play and fish. The Toi Te Ora Public Health(external link) website also monitors algae blooms in the Bay of Plenty area and the Ministry for Primary Industries(external link) website has helpful information regarding toxic algal blooms and shellfish.
2. Look out for signs
Local councils and other organisations may post signage around a lake or river warning people of an algae bloom. If you see one, don’t enter the water and don't fish or gather seafood (kai moana).
3. Is there a bad smell?
Algae blooms can happen suddenly or unpredictably, so a warning may not be online when you check. If a lake or river has an unpleasant smell, then it’s probably a sign that something isn’t right, and you should stay out of the water.
4. Do a visual check
If the lake or river looks discoloured, has surface scum, green or brown particles suspended in it, or brown-black algal mats attached to stream beds, then don’t enter the water as it could be toxic.
5. Don't eat shellfish or fish from areas where there is algal bloom
Toxins build up in mussels more quickly than other types of shellfish. Tuatua, pipi, cockles and toheroa store toxins and can remain dangerous to eat long after an algal bloom has gone. Shellfish that were safe yesterday might not be safe a few days later.
Check this Ministry for Primary Industries page to find an area where shellfish aren't safe to eat.(external link)
6. Keep your animals safe
If it's not safe for you, it's not safe for your pets. Dogs are susceptible to cyanobacterial poisoning or blue-green algae. When ingested (eaten), a piece the size of a 50c coin is enough to kill a dog.
If you think you’ve been exposed to toxic algae and are experiencing symptoms such as nausea, vomiting, diarrhoea, irritation to the skin, nose, mouth and eyes, seek medical attention immediately.
If you think your pet has been exposed, take them to the nearest vet immediately.