With a recurved shape and serrated edges, tiger shark teeth are impeccable "can openers" – even a sea turtle's tough carapace is no match. But thanks to a nifty trick, the reptiles do occasionally thwart those chompers.

A sharks gotta do what a sharks gotta do. We love tigers. Ps the turtle got away!! @ningaloomarineinteractions

A post shared by Frazer McGregor (@frazercoralbay) on May 13, 2017 at 9:03pm PDT

There certainly might be an element of luck involved in this turtle's success (this is a pretty tame attack from a relatively small tiger shark), but there is undoubtedly a method to the turtle's madness. In fact, we've seen this defence strategy before!

Randall Arouz, the founder of marine conservation organisation Pretoma, filmed a similar manoeuvre back in 2014 off Costa Rica's Cocos Islands. "The tiger shark doesn't always win," he told Skyler Thomas of White Shark Video at the time.  

Arouz explains that the behaviour works by keeping the reptile's body perpendicular to a shark's jaws, making it difficult to lock down. (This is much like what would happen if you tried to eat a Pringle held vertically in front of your mouth.) 

If that plan fails, the turtles make tight circles as close to the shark as possible. "This way the shark can't close in," adds Arouz.

Just how long this figure-eight defence continues – and who winds up victorious – depends largely on the shark's commitment to the chase. According to Frazer McGregor, who filmed the recent encounter, the shark in his clip eventually swam off in search of an easier meal. 


Top header image: D Ross Robertson/Wikimedia Commons