New research suggests that great white shark attacks on humans are often a case of mistaken identity.
A study from Macquarie University in Australia found that poachers sometimes attack because they mistake surfers and people swimming for seals and sea lions.
study published in, Journal of the Royal Society Interface, found that juvenile great whites could not significantly tell the difference between life forms.
“We found that surfers, swimmers and pinnipeds (seals and sea lions) on the surface of the ocean would look similar to a white shark from below because these sharks cannot see fine details or colours,” said Laura Ryan. Post-doctoral researcher in animal sensory systems at Macquarie University’s Neurobiology Lab.
The findings, the researchers believe, shed more light on why some sharks, such as great whites, as well as bull and tiger sharks, bite humans, and that non-invasive vision-based devices have been developed. which potentially protect surfers and swimmers. sea animal.
In the study, scientists used underwater images of rectangular floats, seals, people swimming different strokes and people paddling on surfboards of various sizes in a large aquarium at Taronga Zoo, with both stationary and traveling cameras directed at the surface of the water. Compare video.
They applied filters to video footage with shark neuroscience data and used modeling programs to simulate the way that a juvenile white shark would process the movements and shapes of various objects.
When humans swim and climb on surfboards, they resemble a juvenile white shark to seals and sea lions, Dr. Ryan said.
It was hard to distinguish small surfboards from pinnipeds, say the researchers, adding that these may be “more attractive mines” from longboards or even stand-up paddleboards to white sharks.
Since most sharks are completely colorless, scientists say the main visual sign for white sharks is the shape of the silhouette. Therefore, the color on the boards and the wetsuits worn are unlikely to change humans’ impressions of sharks swimming, he said.
While shark bites have increased over the past two decades, marine animals are also at risk, with attack mitigation measures such as shark nets and drumlines further threatening them.
“Understanding why shark bites occur can help us find ways to prevent them, while keeping both humans and sharks safe,” says Dr. Ryan.
Credit: www.independent.co.uk /