1 June, 2017   By: Vanessa Pogorelic

It is remarkable that a fish - the size of a bus – which attracts so much attention, still harbours so many secrets

The whale shark is a big enigma that researcher Brad Norman has spent more than 20 years trying to unravel.

Norman became interested in these mysterious giants in 1994, when, as an aspiring marine biologist, he went to Ningaloo Reef to assist a PhD student studying reef fish.

“Up at Ningaloo a fledgling ecotourism industry had already started around the whale sharks. While there, I found out more about them. Or more precisely, that not a lot was known about whale sharks.”

Many years later, Norman is still trying to find out more about these gentle giants and is now Australia’s leading voice in whale shark research and conservation.

Whale shark at Ningaloo Reef
The biggest fish in the sea, the whale shark has a reputation as a gentle giant
What we do know about whale sharks

Despite the name, whale sharks are not whales. They are actually a type of shark and as so, are the biggest fish in the sea. They have been known to reach up to 20m in length, growing from only 50cm long at birth. With a life span of 80-100 years, whale sharks travel thousands of kilometres.

Truly creatures of the deep, they are thought to dive down as far as 1500-2000m with no need to surface, which, Norman says makes them tricky to study.

“They’re not like whales or dolphins or turtles or dugongs or air-breathing animals that come to the surface. These guys can stay down for months at a time if they want.”

Around the world whale sharks are found in Mexico, the Philippines, Tanzania, the Galapagos Islands and Ningaloo.

A marine researcher swims with a whale sharl
Marine researcher, Sam Reynolds, swims along with a whale shark
Although we know they can reach humpback whale-lengths, most seen in whale shark hotspots around the world, including Ningaloo Marine Park, are just four to eight metres, says Norman.

“The whale sharks at Ningaloo are quite immature so they’re smaller. At most places around the world where you see whale sharks they’re in that immature size range,” he says.

“Very rarely do you see large mature whale sharks and we don’t know why."

The whale shark search


 What Norman and other whale shark researchers are trying to find out is where those mature, larger whale sharks are.

Norman hopes to get some clues through a satellite tracking programme.

Run by his research organisation ECOCEAN, whale sharks are tagged when they visit Ningaloo Reef so their movements can be monitored. The program is also tapping into the keen eyes of the younger generations with schools sponsoring the tags so students can follow their whale sharks online.

Brad Norman with satellite tracking equipment
Brad Norman prepares to deploy a satellite tag on a whale shark
Some of the animals on the ECOCEAN radar are the longest-monitored whale sharks in the world. Two of them, Stumpy and Zorro, have been recorded at Ningaloo Reef over a period of 22 years.

The hope is that the tracking will lead researchers to the biggest mystery of all – where whale sharks go to breed.

“So far there have been no documented records of whale sharks mating or giving birth,” Norman says.

Protecting our gentle giants

Although tourists flock to see them and many researchers around the world are tracking them, whale shark numbers are sadly on the decline. Norman co-authored a report last year that saw the species downgraded from Vulnerable to Endangered on a global scale.

“It’s mostly due to human factors, especially overfishing, primarily for their fins,” Norman says.

“There are some other predatory species that have been known to attack baby whale sharks, but humans remain their main threat.

“We’re working closely with colleagues in many countries to have the fishing of whale sharks prohibited.

“The good news in the meantime is that numbers at Ningaloo appear buoyant and ECOCEAN’s research using photo-identification will, hopefully, confirm the stability of this population.”

A whale shark feeding
A whale shark feeding in the waters off Ningaloo
Getting up close

 
While whale sharks have been sighted at Ningaloo for years, it wasn’t until 1993 that the tourism around them really took off, Norman says.

“It was quite limited at first — local dive operators started offering swimming with whale sharks as a unique ecotourism adventure and the industry soon grew.

He says the whale sharks are quite undisturbed by the presence of tourist boats, which operate within strict parameters, particularly with regard to how close they can get.

“Whale shark tourism has always been regulated by government departments and as a result Ningaloo whale shark tourism is now considered world’s best practice.”

Marine researcher tracking whale sharks
Researcher Sam Reynolds watches a whale shark feeding at the surface
For Norman, Ningaloo remains by far the best place in the world to experience a whale shark swim, in part because of the focus on their conservation and also just because of where it is. “You can have a great day out with the whale sharks, all without interfering with their natural behaviour.

“And they’re right in our own backyard, with the spectacular backdrop of the pristine Ningaloo Reef and ancient Cape Range National Park.”

Twenty years on, Norman says he is yet to tire of the experience of swimming with the whale sharks.

“They’re such friendly and graceful creatures. It’s amazing to see them in their natural environment in the deep blue.”

Every time I get in the water I still think it’s fantastic.”

RAC is a major supporter of ECOCEAN’s work with whale sharks and donate accommodation at the RAC Exmouth Cape Tourist Park during whale shark season. Plans are currently underway for a permanent ECOCEAN research facility to be built at the tourist park.

You can experience a whale shark swim in the stunning Ningaloo Marine Park from mid-March and onwards through the winter months. RAC members save up to 20% on stays at the nearby RAC Exmouth Cape Holiday Park or Ningaloo Reef Resort.

RAC Parks and Resorts

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