A shark scare interrupted the Margaret River Pro on Sunday before the reigning world champion, John John Florence, delivered a masterclass of surfing to claim victory at the second Champions Tour event of the 2017 season.

With Kolohe Andino of the US and Brazil’s Filipe Toledo midway through their semi-final at the Western Australian leg of the World Surf League’s elite competition, organisers erred on the side of caution after spotting a feeding frenzy and called the contestants back to shore.

“The whole bay’s pretty full of salmon and tuna and everything’s feeding, so in amongst all that is a few smaller sharks and we’re just checking for larger sharks at the moment,” the World Surf League’s head judge Rich Porta said. “It’s turned into a full feeding frenzy in the middle of the bay. Safety first, we’ll bring the guys in for a 20-minute hold until the fish move out.”

The pair were ushered out of the water on jet skis as water patrols were deployed and a helicopter surveyed the scene from the skies above. Once given the green light to return to the water, the pair completed their heat without further incident and Andino moved through to the final despite admitting the incident had played on his mind.

“We saw all these splashes and I don’t think either of us could really surf after that,” Andino told Fox Sports. “I paddled over and said ‘I think there’s sharks out here’. I saw so many fish swimming under me and I know the big fish follow the small fish. They said we could go on hold and I said ‘OK’, because I couldn’t really think.”

Andino eventually fell in the final to Florence, who claimed he had not been particularly affected by prospect of an encounter with some hungry marine life. “It is what it is, there’s sharks, there’s fish and there’s whales out there and it’s why we love coming here,” Florence said. “It didn’t bother me; we have good water patrol and it’s all part of surfing in the end.”

Helicopter sent in to check water is clear after large schools of salmon encroach competition area at Margaret River Pro. pic.twitter.com/vApSf0Co4m — Anthony Pancia (@byanthonypancia) April 9, 2017

It is not the first time sharks have interrupted a WSL Champions Tour event: in July 2015, the three-times world champion, Mick Fanning, encountered what was thought to be a great white shark midway through the J-Bay Open in South Africa. The Australian punched the shark on its nose and escaped unharmed from the incident, prompting worldwide headlines, but said afterwards his return to the water would be “a little bit tricky”.

Julian Wilson, who was in the water with Fanning at the time of the attack and swam to the aid of his good friend, told the Guardian last month encounters with marine life are part and parcel of surfing. “It doesn’t matter age you are or where you are, I think everybody gets an inkling that you’re not out there on your own,” he said. “It’s just a part of playing in their back yard.”

Sharks are a common sight in the Margaret River region, especially during times of salmon migration along the coastline. Fisheries WA had released a video at the end of last month warning ocean users that salmon schools were passing through and large numbers of sharks were hunting them. “Reported shark sightings are already on the rise around schooling fish. If you’re swimming or surfing, recognise the danger signs and keep away from large schools of fish,” the video advised.

Florence assumed No1 spot in the world rankings with his victory after Owen Wright, who won the season-opening event at Snapper Rocks, could only make the quarter-finals, where he lost to Jack Freestone. Florence had earlier hurt his elbow in a collision with a shallow reef in his semi-final but he shrugged off the injury to claim the coveted yellow jersey, which he will now wear at the Tour’s next event starting later this week at Bells Beach in Victoria.

“I didn’t know what to do so I jumped and ended up hitting the reef really, really hard,” Florence said. “At first I actually thought I’d broken my elbow, but I came in and had a doctor do some work on it and coupled with the adrenalin of competing, it all came good for the final.”