Hammerhead School

Hammerhead sharks have spectacular vision. Eyes on the very edge of the hammer provide a panoramic view, allowing the shark to see prey from both above and below. But an increased range of vision isn’t the only reason for the shark’s wide, mallet-shaped head. Like all sharks, hammerheads have sensory organs in their snout and head that detect faint electrical currents created by prey. Spread over the broad surface area of the head, these highly specialised sensors allow the shark to scan more of the ocean for potential prey.

Galapagos Shark at night

Pillars of evolution, millions of years in the making the mighty Galápagos shark was first discovered in the waters off the Galápagos Islands. The Galápagos shark is a relentless hunter—armed with more than a dozen rows of saw-like teeth packed inside a wide mouth. Though dangerous, Galápagos sharks rarely attack humans. When threatened, the shark arches its powerful back, lowers its pectoral fins and swims in loops of figure-eights; a classic threat display.

Glass Octopus

The dark, deep waters off Cocos Island provide a habitat for rare and alien creatures seldom seen by humans. Nearly transparent, the Glass Octopus is not able to change colour like many of its cousins. A translucent, almost-colourless body makes it less visible to predators. Elongated eyes limit peripheral vision, but may minimise the silhouette of the eye when seen from below, further aiding its camouflage.

School of Trevally

Trevally, or jacks, travel in tightly organized schools to confuse predators. Picking out individual prey from a twisting, shining mass is not an easy task for a visually oriented hunter. Swimming in unison, the fish may appear as a single large creature to would-be predators.

Whitetip Night Hunt

Whitetip sharks at Cocos Island hunt at night, assembling over the ocean floor each night in hungry armies. Whereas in the day these sharks lay resting in caves or swimming calmly over the reef, at night they are aggressive: poking their broad heads into holes in the coral to flush out small crustaceans and bony fish. Tough skin, protective eye ridges and slender bodies allow the sharks to force their way into crevices.

Destination spotlight: Underwater around the world’s ‘most beautiful island’

By Geoff May

Dive into Costa Rica’s underwater paradise with these amazing photos, captured whilst filming for Love Nature’s upcoming new show Great Blue Wild, coming soon

Located approximately 550km (342 miles) off Costa Rica’s Pacific shore, Cocos Island is one of the country’s foremost national parks. The island is home to a number of magnificent animals, on land, but especially in the surrounding waters too.

Under the waves, you’ll find 30 different species of coral reef, 60 species of crustacean, 600 different types molluscs and over 300 separate species of fish. Hammerhead sharks, giant mantas, bottlenose dolphins, humpback whales and three different types of sea turtle can all be seen swimming around this underwater paradise.

Indeed, Cocos is so diverse in wildlife—both above ground and under the waves—that Jacques Cousteau himself claimed it to be ‘the most beautiful island in the world.’

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