Sea lice warning extends to Auckland’s Mission Bay, Waiheke Island and 20 city beaches

• Swimmers at Mission Bay report itchy rashes from sea lice, joining Waiheke as newly affected areas.
• Authorities advise caution at about 20 city swim spots, from Ōrewa in the north to Beachlands in the east.
• Warmer waters create ideal conditions for sea lice, but experts say they’re not sinister.

One of Auckland’s most popular cityside beaches is now on a sea lice watchlist as the small marine animals with a sting that can cause rashes spread further along the eastern coastline.

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

The Safeswim website, which provides updates on health risks at the region’s beaches, has issued a safety warning for the eastern bay beach as the extent of the scourge worsens.

Mission Bay joins three Waiheke Island swim spots, including tourist hotspot Ōnetangi, as the latest to report having the microscopic marine critters in the water.

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.

Sea lice have been reported at Mission Bay, Beachlands and Waiheke Island's Ōnetangi, and swimmers have been left with itchy rashes. Photo / Supplied

“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.

“Seabather’s 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 not to 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.