The basking shark needs to eat huge quantities of plankton and small invertebrates, and swims thousands of miles each year to follow the best supply.

Atlas of Oceans by John Farndon, is available from Australian Geographic.

The tropical Pacific is dotted with stunningly beautiful coral islands such as these, the Rock Islands of Palau. Palau is a pioneer in the protection of Micronesia’s coasts, and in 2009 created the world’s first shark sanctuary, banning all shark fishing within its coastal waters.

Atlas of Oceans by John Farndon, is available from Australian Geographic.

The remarkable marine lakes of Palau Island in the Pacific, linked to the sea by fissures in the reef rock, are teeming with their own unique species of jellyfish, the golden jellyfish, above, and the moon jellyfish.

Atlas of Oceans by John Farndon,is available from Australian Geographic.

Walruses like to haul themselves onto floating ice packs to bask and breed, but they are being forced ashore more and more as Arctic ice melts.

Atlas of Oceans by John Farndon, is available from Australian Geographic.

The tropical waters of the mangrove forests of northern Australia are home to the world’s largest living reptile, the saltwater crocodile, which can grow up to 6m long. Here, a young ‘salty’, as the Australians call it, noses among the mangrove roots.

Atlas of Oceans by John Farndon, is available from Australian Geographic.

The potentially fatal muzzle on this poor bottlenose dolphin is all too recognisably a plastic six-pack beer can holder. Dolphins are particularly susceptible to entanglement because of their curiosity.

Atlas of Oceans by John Farndon, is available from Australian Geographic.

Enypniastes sp. is one of many interesting deep-sea creatures discovered by the Marine Census. It looks like a jellyfish, but is actually a sea cucumber, an echinoderm related to starfish, and feeds on seabed sediment.

Atlas of Oceans by John Farndon, is available from Australian Geographic.

The Indian ocean village of Weligama, Sri Lanka is famous for its stilt fishermen. Each fisherman perches on a cross-bar at the top of a pole stuck into the seabed close to the shore, so that the fish they are hunting are unaware of their presence.

Atlas of Oceans by John Farndon, is available from Australian Geographic.

The extraordinary big-mouth gulper eel doesn’t swim much, but then it does not need to. With a mouth this big, it just glides slowly along and opens its gigantic jaws to swallow prey that is even larger than itself.

Atlas of Oceans by John Farndon, is available from Australian Geographic.

The powerful waves generated by a hurricane reach much farther below the surface of the water than normal waves – and can wreck fragile coral reefs as this picture shows. Reefs may be increasingly at risk of serious damage as global warming boosts the frequency and power of hurricanes.

Atlas of Oceans by John Farndon, is available from Australian Geographic.