Swim with whale sharks at Ningaloo Reef
The largest fish in the sea, whale sharks can grow up to 12 metres in length and weigh over 21 tonnes. Every March or April these gentle, slow-moving creatures migrate to the Ningaloo Reef, off the Coral Coast in Western Australia, where they feast on the abundant plankton until July. During this period, it is possible to snorkel alongside these majestic fish, though tourist numbers are strictly controlled to prevent the whale sharks from being overwhelmed. While you're in the water you may also spot some of the reef's other inhabitants, which include humpback whales and spinner dolphins.
Swim with manta rays at the Great Barrier Reef
Off the Queensland coast, spanning almost 350,000 square kilometres and composed of over 2,900 separate coral reefs, the Great Barrier Reef is the biggest of its kind in the world. It is blessed with a dazzling range of species – from humpback whales to angelfish, bottlenose dolphins to leatherback turtles – which you can see at close quarters. It is possible hand-feed baby stingrays at Daydream Island, watch turtle hatchings on Heron Island or snorkel along self-guided aquatic trails off Magnetic Island. But one of the most memorable experiences at the Great Barrier Reef is swimming with manta rays off Lady Elliot Island. These placid giants, which have a wingspan of up to seven metres and feed on plankton, appear in the largest numbers in the May-June period, when water visibility is also at its clearest.
Swim with sea lions off Port Lincoln
The bustling South Australian city of Port Lincoln is home to the country's biggest fishing fleet, and has much to offer anglers and seafood fans. There are also opportunities to snorkel or dive with some of the most fun-loving creatures in the sea, the endangered Australian sea lion. A short boat ride from the port takes you to the rather misleadingly-named Seal Cove, where you can swim with these remarkably dog-like creatures as they perform their underwater acrobatics.
Swim with double-headed wrasse in the Lord Howe Island Marine Park
Situated in the Tasman Sea, some 600km off the coast of Port Macquarie in New South Wales, the crescent-shaped Lord Howe Island is the remnant of an extinct volcano and measures only 11km by 3km. The protected waters around this idyllic UNESCO World Heritage Site boast over 500 different species of fish, some of which are found nowhere else on earth, including the dark-blue, dog-sized double-headed wrasse. Swimming, snorkelling and diving opportunities abound, while at the Neds Beach Sanctuary Zone, you can even wade out into the water and feed the mullet, garfish, silver drummer, kingfish and spangled emperor by hand.
Swim with Burrunan dolphins in Port Phillip Bay
Melbourne sits on the edge of Port Phillip Bay, which spans almost 2,000 sq km and contains a multitude of marine life, including a rare subspecies of bottlenose dolphin found only in the waters around the state of Victoria. Burrunan dolphins take their name from an Aboriginal word for "large sea fish of the porpoise kind". Just as curious as their better-known cousins, they love to play alongside boats and swimmers. Sightings are most common between October and April.
Swim with fur seals off the Tasman Peninsula
The rugged Tasman Peninsula in southeastern Tasmania, 95km outside Hobart, boasts a series of world-class diving sites, including around Hippolyte Rocks, a favoured haunt for fairy penguins, the short-tailed shearwater and – most notably – great colonies of fur seals. These inquisitive creatures enjoy interacting with divers and snorkelers. If you're lucky, you might also spot a pod of dolphins while you're in the water.
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