New research has shed light on why people get into danger so easily at New Zealand beaches.
Every year around 700 people are rescued from rip currents.
As an experienced surf lifeguard Stu Bryce knows how to spot a rip, he's able to point out exactly where they are.
"There will be rips around the rocks at both ends of the bay with the water coming in and out," he explains just by looking out to sea.
A rip is a strong current of water moving directly offshore and whilst spotting them is second nature to Bryce, it's something the majority of Kiwi beachgoers can't do -according to researchers, who spent time at Auckland's Muriwai beach surveying swimmers.
Senior lecturer in physical geography Seb Pitman says the research revolved around seeing whether people were able to identify rips.
"We asked them to look at rip currents in photos because that's generally how people are educated in schools, and then from that, we also asked them to pick out the rip current in front of them and at the time there was a really huge dangerous rip operating at Muriwai."
Seventy-eight percent of the survey's participants couldn't spot the rip right in front of them
"In static photos that are used in education pieces the rip current is framed in the dead centre so it's really obvious," says Pitman.
"People think they can do it from a photograph but as soon as you give them moving water breaking waves all of this extra information to take in it's not working."
The dangers of that are evident, on average five people drown in rip currents each year and a further 700 need rescuing.
Recently 27 swimmers were plucked from a rip on Sumner Beach in just over 10 minutes.
Pitman would like to see the education around rips modernised.
"We want to move to videos and make those videos more accessible and also use 3D headsets if we can to really immerse people in that situation."
Stu Bryce says if in doubt, ask a lifeguard and always swim between the flags.