On Ningaloo Reef on Australia’s Coral Coast, March and April see an extraordinary explosion of life, with coral spawning rejuvenating the reef, while providing a smorgasbord of dining for the reef’s largest inhabitants.

Feature by Carolyn Beasley

As the sun sets on Ningaloo Reef / Nyinggulu, butterflyfish retreat inside protective coral fingers and parrotfish snooze inside their protective mucous sleeping bag. Moray eels and octopuses are waking up, hungry.

It’s just over a week since the last full moon. The neap tides create little water movement and the water temperature is just right. Tuned into intricate signals in nature, a tiny anemone-like animal just millimetres wide, a coral polyp, unfolds its tentacles and presents a small bundle of eggs to the wild ocean. Clouds of sperm and eggs are released from other coral polyps in the neighbourhood, and even from corals a hundred kilometres away.

_{Coral in Ningaloo Reef}

This reproductive fiesta is known as mass coral spawning, and at Ningaloo Reef it occurs in March and April. The mass spawning lasts only a few nights, but some corals may spawn throughout autumn. By broadcasting millions of eggs and sperm at once, the corals ensure that some will connect and fertilise, perpetuating the species. These baby coral larvae will float with the currents before settling out to start new coral colonies, replenishing the reef.

At 300-kilometres long, the UNESCO World Heritage-listed Ningaloo Reef is one of the largest fringing reefs in the world. It hugs the shore near Exmouth  and Coral Bay, home to the Jinigudera & Baiyungu, with aquamarine coral lagoons slotted between the ancient red canyons of the Cape Range National Park and the deep blue wonders of Ningaloo Marine Park. In just a few fin kicks, visitors can join a school of stripy convict surgeon fish, come eye to eye with a grazing turtle, or admire a blue-spotted stingray.

_{Marine life on the Ningaloo Reef}

With the coral spawning only occurring at night, most visitors will only observe a pink tinge of eggs floating on the ocean. But there are other signs here, and they’re slightly more obvious.

Coral spawning provides a nutritious feeding bonanza for microscopic plankton and swarms of the shrimp-like krill. This abundance is an irresistible drawcard for some of Ningaloo’s most famous inhabitants, the enigmatic whale sharks. Migratory visitors, whale sharks appear here from March to August each year, tuning in to the invisible rhythm of the reef.

Whale sharks can grow up to 18 metres in length, although most whale sharks visiting Ningaloo are adolescent males, between two and 12 metres in length. Whale sharks are toothless, harmless giants, and although their filter-feeding mouths may be up to 1.5 metres wide, you’re completely safe unless you’re plankton.

_{Whale Shark in Ningaloo Reef}

With around 600 whale sharks visiting annually, this is the world’s biggest aggregation and the only place in Australia with reliable sightings.  Understandably, visitors flock here to join a licensed tour operator from Exmouth or Coral Bay for an unforgettable, ‘pinch-me’ experience, swimming beside the world’s biggest fish.

Following your experienced guide, you’ll hover in the water as the whale shark approaches close to the surface. Peering through the water, the first thing you’ll notice is the cavernous mouth, sifting out tasty planktonic morsels as it swims towards you.

Its spotty body becomes level with you as it continues on its trajectory, unfazed by the awestruck humans that fin along beside it. You’ll feel tiny as you absorb the effortless grace and sheer size of the behemoth, until inevitably you can’t keep up, and its slow-motion tail swishes into the blue.

_{Swimming with a Whale Shark in Ningaloo}

Although whale sharks are illegally fished in other countries, Ningaloo’s whale sharks are well protected under state and federal laws. Safe-guarding the whale sharks and the safety of the swimmers, strict rules control these interactions. Each tour boat has experienced guides who ensure swimmers maintain a safe distance from the whale shark and prevent it from needing to alter its path.

Only 10 guests and a guide are permitted in the water with a whale shark at once. All companies provide an educational experience, and most contribute to scientific research by submitting photographs of the whale shark’s unique markings to a research group, which contributes to understanding and conservation this mysterious species.

During your tour, you’ll get the chance to snorkel with many of Ningaloo’s other 500 species of fish. If you’re lucky, you may even spot another gentle giant, the manta ray. They’re resident here all year round and are particularly plentiful at Coral Bay.

_{Mantarays in the Ningaloo Marine Park}

Of course, the reef’s biggest creatures will steal the show, but don’t overlook Ningaloo’s architects, the 300 species of coral. Take a moment to appreciate these tiny creatures tucked inside their limestone skeletons; they’re the beating heart of all life on the reef.

Published March 2023.