Sharks can see contrast quite well, thus any high-contrast clothing or equipment worn by a person in the water will be very noticeable to sharks. Human rescuers searching for missing people in the sea are able to notice bright yellow flotation devices and rafts, which is the usual hue used in water safety.
Humorously referred to as “yum yum yellow,” many people think that this may make you more noticeable to sharks. Yellow may not be as enticing as once thought, because the majority of sharks are colourblind.
Should all of these gadgets be swapped out by ones that are duller in colour? There are trade-offs involved, of course, but most people would concur that the advantage of improving one’s chances of being rescued far outweighs the incredibly small risk of drawing a shark.
Divers and swimmers can possibly lower their risk of coming into contact with a shark by refraining from wearing swimwear or dive gear that is extremely bright or contrasting. During diving, we personally favour using dark blue or black fins, masks, tanks, and wetsuits.
Make it a point to tuck your diving watch under the sleeve of your wetsuit to completely eliminate the possibility that a shark or barracuda will be attracted by the light reflecting off the watch’s face.
Similarly to this, one should never wear jewellery since the glint of light off metal is similar to the glint of light off fish scales, which are the majority of sharks’ preferred prey.
Resource: https://www.floridamuseum.ufl.edu/shark-attacks/reduce-risk/apparel-color/
