Horse-Eye Jack

Photo: dogsarethecoolest · CC BY-NC

Dense schools of horse-eye jacks of several hundred individuals wheel in coordinated spirals at the reef crest of Mustique Wall, particularly in the morning hours before dispersing to hunt across the reef. Their large eyes give them a visual advantage in the low-light conditions of early morning hunting, and their schooling behaviour provides safety in numbers against the resident sharks. Watching a jack school react to a shark pass — flashing silver as individuals shift simultaneously — is one of the most dramatic spectacles Caribbean reef diving offers.