When blue-green algae blooms it can be a cause for concern and is often reported to the NT EPA as an oily, frothy or jelly-like slick along beaches or in the water.
This common natural phenomenon begins to appear at the end of the dry season and can usually be seen from October onwards. In some cases it reduces water quality and poses a health risk to people and animals.
These algal blooms may look like brown discoloured water or blue-green scum and have a strong odour.
Blue-green algae has the potential to produce toxins as the bloom ages or begins to die and it's these toxins that can cause irritation to the skin, eyes and respiratory system on contact.
Seafood caught in algal infested waters can also be harmful to people and should not be eaten.
The NT EPA also warns pet owners that consumption of toxic algae by animals may cause illness or even death. This is especially relevant for dogs that tend to lick their coats after swimming.
The NT EPA recommends people, and their dogs, stay out of the water when plumes are present.