There's more to Ningaloo Reef than the world's biggest shark

In the waters beyond Ningaloo Reef, a shark is circling. More than seven metres in length, it's larger than any great white, but has infinitely more pleasant table manners.

As I kick my fins and glide beside it, the whale shark appears oblivious, its gills rippling and its tail flicking languidly as it hoovers up plankton. I might just be another of the many fish tailing along for the ride.

Each autumn, the world's largest fish appears in these waters offshore from Exmouth, drawn by the krill and plankton that are in turn here to indulge in the feast that is the annual coral spawning, which takes place after a full moon in March or April.

For visitors, it's the greatest natural show in town – 36,000 people took tours to swim with whale sharks in 2022 – and while it's an extraordinary experience to swim beside a whale shark, with just three metres of water between you and up to nine metres of fish, it's also often only part of the marine encounter.

At Ningaloo, you might come for the whale sharks, but find yourself immersed in a world of other whales and sharks.

The World Heritage-listed Ningaloo Reef is the planet's largest fringing reef, running at times just a few hundred metres from shore. As we're transported by zodiac to the whale shark boat, the reef is visible as a white line of breaking waves etched into the Indian Ocean, creating a virtual lagoon along the shores of barren North West Cape.

There are three breaks in the reef, through which the boat can punch out into the ocean, but first it pauses at a mooring inside the reef for a preparatory snorkel. Even as 20-knot winds stir the sea beyond the reef, it's a millpond inside, and we plunge into the water among a constellation of coral bommies. The air temperature is 22 degrees, and the water is 25 degrees – it's like sinking into a soothing bath.

As I drift with the currents, bommies pass beneath me, looking like drawings of brains. Fish as colourful as paint charts squirt about, and a blacktip reef shark circles a few metres below me. Duck dive to the sandy seabed and it's not unusual to find these placid sharks snoozing beneath the bommies.

Outside the reef, there's no guarantee of whale shark sightings, but the odds well and truly favour it – last year, more than 97% of visitors witnessed the creature that guides refer to as "our spotted fish". Spotter planes circle in the sky, directing boat skippers, and it's mere minutes this day before word comes of a whale shark near to our boat.

These colossal fish grow up to 12 metres in length – the largest recorded was almost 19 metres – though those seen around Ningaloo Reef are more commonly around three to eight metres. As you take to the water and begin swimming, the fish beside you might be up to four times your body length.

For a few minutes, we're like a pelagic peloton – this slow-moving shark and an entourage of wetsuit-clad humans skimming across the surface of the ocean. Over the course of the day, I will swim seven times beside this shark and one other, no less awed in the final swim than the first, but there are even bigger things in these waters than whale sharks.

Even as we'd motored out from the shores in the morning, there'd been talk of sightings of humpback whales, which migrate along the West Australian coast from June to November.

Any wildlife encounter has a fluky and fabulous quality, and as I swim beside the whale shark for the final time, I suddenly notice I'm alone, swimming carefree until I hear shrieks, muffled by the water.

Less than 100 metres from where I swim, a humpback is breaching, torpedoing out of the ocean and crashing back down in a thunderous firework of water.

We gather like chicks and swim for the boat, but it's an unforgettable marine collage – a whale shark so near and this humpback whale not much further away. Two whales, two tales.

Air New Zealand has daily non-stop flights to Perth with onward connections to Exmouth. Qantas launches its first direct Melbourne-Exmouth flights on April 30. See: ;

Life's an Adventure operates a seven-day Karijini National Park Walk and Ningaloo Reef trip, starting from A$5199 (NZ$5599), that includes a day swimming with whale sharks. See

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