Lion's mane jellyfish stinging Kiwi swimmers

Lion's mane jellyfish stinging Kiwi swimmers

As the weather warms up, there are increasing reports of stinging jellyfish along New Zealand beaches, and some Auckland swimmers are refusing to go into the infested waters.

Kate Lewis Kenedi has been swimming with a group at Narrow Neck Beach for eight years, but she'd never experienced swarms of jellyfish before.

"There were jellyfish on the beach and in the water, thick. You had to walk through them to get in the water.

"Then as we swam they never stopped. I thought there might be fewer as we went out, but that didn't work, so we just swam through them."

By the time she realised she was getting stung, it was too late.

"We wear wetsuits most of us, so we were stung where we had exposed skin, hands, wrists, face, neck, feet, ankles. It's irritating and burny and painful. Then over the next few days it got itchy, and then eventually went away."

The pink and purple lion's mane jellies are the largest in the world, with some species growing up two metres.

They've swarmed swimmers in Nelson. Some in Whangaparaoa were the size of dinner plates, while one at Whangarei Heads is thought to have measured nearly a metre.

Marine curator at Auckland Museum Dr Wilma Blom says we don't have the dangerous jellies that Australia has, but swimmers should avoid them in the water.

"When they're out in the water and they still have those trailing tentacles, which can get quite long, metres possibly, and they carry all the stinging cells, and those are the bits you want to beware of basically."

They can leave you with a nasty sting, best treated with a towel soaked in seawater, vinegar or even urine. Don't use fresh water as it activates the stingers.

Dr Blom says we are seeing more jellyfish, but whether it's because of climate change, increased nutrients in the water, fewer predators or over fishing, the science is still out.  

"Although you can see they can swim, they don't have an awful lot of direction of where they go. It could just be currents or wind direction."

And once they're in our bays and harbours, it's difficult for them to get out, so it may not be the last we see of the stinging jellies in our waters.

For tips on jellyfish stings, visit the Ministry of Health's website.