Amateur paddleboarders are being urged to be careful if they head on to the water over the bank holiday weekend.
Three children and one adult were rescued on Friday off Anglesey after strong offshore winds and the aftermath of Storm Lilian blew them out to sea.
It came after 14 people were rescued by Swansea’s RNLI teams two weekends ago, with others reported by Port Talbot and Pembrokeshire crews.
Anna Snow of the RNLI said people needed to know what they were doing before jumping on the boards.
About 600,000 people in the UK regularly paddleboard, according to sporting organisation Stand Up Paddleboarding (SUP).
One adult and three children were paddleboarding at Traeth yr Ora in north-east Anglesey before getting into difficulty and needing to be rescued.
Gaz Owen, who was at the helm of the rescue boat, said Friday “was not the day to go” due to the “strong offshore wind”.
“Even the most experienced water users can be in trouble in such conditions,” he said.
“We always advise anyone heading out to sea to wear a flotation device and make sure they have a means of communication. It can make all the difference in an emergency.”
Meanwhile, Coastguard crews are warning people against “playing chicken” with strong waves to take a selfie.
It comes after one young person was “knocked over by one wave and almost taken out” on the slipway at Port Talbot on Thursday.
“It looks spectacular but surges can easily sweep a person off their feet and into trouble,” said the Coastguard in a Facebook post.
“A dramatic photograph or selfie is not worth risking your life.”
Sarah Perkins, from Cardiff, who has been an SUP racer for eight years, having windsurfed before then, said paddleboard skills take a long time to build and she sees a lot of people struggling.
“It’s a really accessible support but it’s not easy,” she said.
“I see a lot of people out and they are not very skilled and if they were just a tiny bit more skilled they would be having so much more fun.”
Sarah has competed in three world championships and will head to Copenhagen in September to compete internationally again.
She said she had seen people with boards the wrong way round and leashes, which should be attached to legs or waists, around people’s wrists.
Conversations with experts or lifeguards could make a big difference, she added.
“You don’t know what you don’t know.
“If you don’t understand what an offshore wind looks like, if you don’t understand what river conditions are dangerous then you don’t have a clue.”
Gareth Stevenson runs Get Out On The Water, which helps train and facilitate water sports in south Wales.
He said Covid restrictions and accessibility of equipment had boosted paddleboarding’s popularity.
“There was an explosion in paddleboarding during Covid and those years where we were not able to travel,” he said.
“Everyone bought a paddleboard and had a go. We haven’t seen it in another sport in the same way, going from complete beginners to guys competing at international levels.”
He said paddleboarding was a “great social activity” but said people needed to develop core skills before venturing on to the water.
“The key thing is to learn safety. Read the environment, know where you’re paddling from and to have the right equipment with you at all times.
“It’s the same as walking up a mountain,” he said.
“Have a form of communication with you, let people know where you are going and paddle with friends.”
Ms Snow, from the RNLI, said the organisation wanted people to enjoy the coast but be prepared in case they get into trouble.
“It’s very dangerous unfortunately,” she said.
She said the charity had been called to many careless situations but “don’t judge” and urged everyone to call at the first sign of trouble.
Checking tide and wind speeds were simple ways to get the most out of the sport, she added.
“Paddleboarding is a very enjoyable and accessible sport.
“It’s gets people, who might otherwise not be able to get on the water, on it.”