Researchers from Australia’s Macquarie University in Sydney found that swimming or paddle boarding humans bear a strong likeness to seals and sea lions in the eyes of juvenile white sharks.
Great white sharks, along with bull sharks and tiger sharks, account for the most bites on humans, researchers said in a press release Wednesday.
They are the world’s largest predatory fish, according to the World Wildlife Fund (WWF), and are known to rip chunks out of their prey, which are swallowed whole.
But in spite of their fearsome reputation, great white sharks are a vulnerable species and their numbers are decreasing, according to WWF.
Researchers studied and compared underwater videos of seals, sea lions and humans swimming in various ways, along with rectangular floats and humans paddling on different sized surfboards, using stationary and traveling cameras to capture the footage.
“We attached a GoPro to an underwater scooter, and set it to travel at a typical cruising speed for predatory sharks,” lead author Laura Ryan, a post-doctoral researcher in animal sensory systems at Macquarie University’s Neurobiology Lab, said in a statement.
Using a catalog of shark neuroscience data, researchers then applied filters to the video footage and created modeling programs that would simulate the way in which a young white shark would see the movements and shapes of different objects.
Researchers confirmed that humans who swim and paddle surfboards bear a strong resemblance to seals and sea lions in the eyes of young white sharks, supporting the mistaken identity theory behind some bites.
Most sharks are color blind, meaning that colors on surfboards and wetsuits make little difference when it comes to a shark’s view of humans in the water, researchers said.
“Understanding why shark bites occur can help us find ways to prevent them, while keeping both humans and sharks safer,” Ryan added.