Computer model shows why sharks attack surfers

Dozens of people are attacked by sharks every year. Although the number of attacks decreases year by year, for tourist cities even one incident is heavy drama - it scares away tourists. Now scientists say they have confirmed the old theory, using computer simulations, that sharks attack surfers because they mistake them for seals.

A large percentage of attacks are by great white sharks, which attack surfers when they are sitting on their boards or paddling. Seen from below, the silhouette of the surfers resembles that of pinnipeds (seals and sea lions) - and these animals are natural prey for the great white shark.

Led by researcher Laura Ryan, scientists from Australia's Macquarie University recently set out to further explore this theory. They used a large number of cameras to capture underwater video of objects such as surfboards, people on surfboards, hands slapping the surface of the water, and other situations.

The footage was then analyzed using computer models based on existing neuroscience data on sharks, simulating young great white sharks' perception of the shapes and movements of various objects. The analysis confirmed that young great white sharks do tend to confuse people on surfboards with pinnipeds because they likely perceive them as very similar - this is especially true for people on short boards.

Changing the color of the boards is unlikely to help, as sharks are thought to be colorblind. However, scientists are considering other preventative measures, such as adding high-intensity LEDs to the underside of the boards to "break up" their silhouette.

Source: newatlas