Surf lifesavers due to monitor the Noosa event refused to enter the water after a sighting at first light. ( Supplied: Benjamin Harder )
Organisers of the Noosa Triathlon in Queensland were forced to cancel the swim leg of the famous event after sharks were spotted in the water an hour before the event began.
The Noosa event is the largest Olympic distance triathlon in the world and draws 8,500 athletes and 20,000 spectators each year.
Noosa Main Beach was temporarily closed on Saturday after sharks were spotted offshore.
On Saturday night, organisers modified the event to reduce the swimming distance to about 1 kilometre in order to keep swimmers in the shallows.
But early on Sunday morning, just before the race began, organisers scrapped the swim leg entirely.
Surf lifesavers who were due to monitor the event refused to enter the water after another sighting at first light.
"The Noosa Triathlon team is not able to put water safety [personnel] on the water due to marine life present," organisers posted on social media.
"The swim will not be taking place."
Matt Hauser celebrates winning the elite category of the 2026 Noosa Triathlon. ( Supplied: Korupt Vision )
The event, which became a duathlon, was won by Matt Hauser, who backed up his victory last year.
His completed the race in 1:39:34 after organisers added a 5km run in place of the swim.
Competitors then cycled 40km and ran 10km for the other legs.
