Swimmers at one of Auckland’s most popular beaches are among the latest to find themselves “mauled by sea lice” as the small animals spread further along the city’s coastline.

Mission Bay swimmers have now been reporting getting covered in itchy red rashes after taking a dip in the sea as authorities advise people to exercise caution at about 20 city swimspots.

Mission Bay joins Beachlands in east Auckland and three Waiheke Island swimspots, including tourist hotspot Onetangi, as the latest to report having the microscopic marine critters.

Auckland mother, Hayley Schelling, told the Herald yesterday her son was up all night scratching his itchy torso after he was stung at a northern city beach.

“He wears a swim top so they must have got stuck up there ... they do seem quite big,” she said.

She was among northern beach swimmers, including those at Milford, Ōrewa, Stanmore Bay and Red Beach, to take to Facebook documenting scores of cases of severe itching and rashes.

“I was panicking ... I thought it was chickenpox,” another concerned parent said after their kids were “absolutely covered” in stings when swimming at a Hibiscus Coast beach.

“Our family have been hit hard by sea lice yesterday at Red Beach, the worst case so far,” said another.

“My boy went swimming in Stanmore Bay beach yesterday and got mauled by sea lice.”

Sea lice (or isopods) typically grow up to 1.5mm long and tend to live in warm, shallow sand or rock pools, or near the shoreline.

“Seabathers eruption” is an itchy rash of the skin that appears mainly on covered areas soon after swimming in the sea, often caused by stings from sea lice, thimble jellyfish or microscopic sea anemones.

Auckland beachgoers are reporting symptoms similar to chicken pox following an influx of sea lice in the region.

Optimal conditions

Niwa crustacean biologist Dr Rachael Peart said this year’s warmer waters made for ideal conditions for sea lice.

Beachgoers are asked to be cautious of sea lice and other minuscule ocean critters.

However, she urged people to not let the critters discourage them from enjoying the warmer weather.

“Most of the time it’s just bad luck, wrong place wrong time really. But they’re not sinister.”

Advice to swimmers if you get stung

• Make sure you remove your swimwear after taking a dip
• Shower in freshwater straight away
• Do your best to avoid scratching to reduce the chance of infection.

- NZ Herald