Sharks are visual predators that predominately use the element of surprise when attacking (Strong,1996), usually attacking from behind and beneath its prey (Tricas and McCosker 1984). Strong(1996) found sharks were initially attracted to their prey with sense of smell but appeared to use vision the closer it approached.
A shark’s vision is well developed and more elaborate than most fishes (Gilbert, 1963), having duplex retinas containing both rod and cone photoreceptors (Gruber & Cohen, 1985) indicating they have high visual capabilities and ability to see colour.
When predating, sharks undertake a risk assessment before attacking its prey (Lima and Dill, 1989; Martin et al., 2005) and it’s at this point where “Shark eyes” is designed to assist watermen.
“Shark Eyes” is intended to signal the approaching predator that it has been detected, effectively saying “I’ve seen you” and thereby altering the shark’s predatory behaviour.
“Shark Eyes” therefore aims to alter the sharks risk assessment and deter the shark from attacking. By taking away the element of surprise, the shark has a reduced chance of successfully capturing its prey. For example, an adult white shark is usually not agile enough to capture a fleeing, darting seal hence it generally attacks its prey by surprise (Tricas and McCosker, 1984). Similarly, Strong (1996) observed in numerous occasions that fur seals and sea lions easily avoided white sharks, suggesting that once the shark was visually detected, the change of capture of the seal prey drop considerably. Once a shark sees the “Shark eyes” and realises it has been detected, it may now be optimal for the shark to abandon its attack.
As described by Martin et al., (2005) the stages of predatory behaviour by a white shark involves a “Gather Info” stage before deciding to “Strike” or “Abort” an attack. It’s at this “Gather Info” stage that “Shark Eyes” aims to influence the sharks risk assessment, altering the shark’s behaviour to “Abort”.
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