Auckland swimmers are being warned to take care as several beaches experience jellyfish blooms.
Children and those with allergies may be especially affected by jellyfish stings. (file pic) Photo: RNZ/Caitlin Cherry
A jellyfish bloom is a sharp rise in jellyfish numbers within a short period of time.
Auckland Regional Public Health said warm water is attracting the jellyfish towards shore.
Their stings can cause some beachgoers to break out in a rash known as "sea-bather's eruption".
The health authority said children and those with allergies may get more severe reactions and become unwell for several days.
Bluebottle jellyfish - which produce a nasty sting - have also been spotted around the coast, with people being told to stay out of the water if these jellyfish are present.
Bluebottle jellyfish should also be avoided, Auckland Regional Public Health says. Photo: 123RF