An Australian research team has found a simple and cost-effective light solution could help reduce great white shark attacks on surfers. It was found that surfers are particularly vulnerable as sharks could mistake them for seals. This breakthrough study from Sydney‘s Macquarie University team’s ground-breaking research promises a fail-safe method to prevent great white sharks from confusing surfers for prey. The study was undertaken in Mossel Bay in the Western Cape.
Dr Laura Ryan and her team, in a series of experiments, studied more than 500 hours of great white shark behaviour, using seal-like decoys, towing them around. Some decoys were fitted with various lighting patterns, in the form of horizontal or vertical strip or strobe lights with varying levels of brightness. These illuminated decoys were tested against unlit control decoys.
“We have taken this approach to understand these animals’ sensory systems, how they see the world and their behaviour,” Dr Laura Ryan
The findings, published t in Current Biology, showed sharks were most interested in unlit decoys, while strobe lights reduced shark interest somewhat. However, vertical strip lighting was highly effective in deterring these predators.
Decoys and Bright Lights to Reduce Shark Attacks
The most successful deterrent was horizontal lighting at maximum brightness in which sharks showed no interest in the decoys. This led to the conclusion that the bright horizontal lighting effectively broke the decoy’s silhouette, rendering it less recognisable as potential prey.
According to Dr Ryan, the brightness on the decoy had to be brighter than or equal to the background light and as long as the lighting stopped the silhouette from looking black, it seemed to work. The study offers real hope for increased safety in the surf, as LED’s could soon be adapted for surfboards and wetsuits. The team will also do research into providing protection for swimmers and not only surfers.
