Distorted silhouette

Light on surfboards protects against shark attacks

A great white shark in Mossel Bay, South Africa(Bild: Conchi Martinez)

Lights on surfboards were previously seen as an invitation for sharks to attack. In fact, the exact opposite may be the case, as an Australian study now shows. The light would distort the silhouette of the board, making the prey less attractive to the predatory fish.

Great white sharks often attack their prey from below and sometimes mistake a surfer for a seal, explained biologist Laura Ryan from Australia's Macquarie University. If bright lights, such as LED lights, are placed horizontally under the surfboard, this distorts the silhouette of the board on the surface of the sea. This makes the board less "appetizing" for sharks.

Bright and horizontal is best
The experiments were carried out in Mossel Bay in South Africa. This is an area that is popular with great white sharks. The research team used seal-shaped dummies, fitted them with LED lights and towed them behind a boat. The aim was to find out which object attracted the most attention from the sharks.

The result: the brightest lights deterred the sea creatures the most. Horizontal lights had a better effect than vertical lights. "The fear of great white sharks has been around for a long time. This is partly because we don't understand them very well," said Ryan.

The study was published in the journal "Biology". The biologist now wants to build prototypes to be placed under kayaks or surfboards.