On Western Australia's Ningaloo Reef off Exmouth, a bait ball shows the ecosystem's intricate food chain in action.
It’s 6 o’clock in the morning. The alarm goes off as it does every day. And just like every other day, I press snooze. I slip back into limbo, thinking of all the places I have been to in the last six months and all the beautiful creatures I have been lucky enough to see in the wild. Amazon basin, Norwegian fjords, South African Karoo. Fresh water dolphins, sea lions, humpback whales. The alarm goes off again. Today, I wake up in Australia, and I am already late. My friends are waiting for me.
Despite the bad forecast from the day before, we decided to give it a go anyway. I quickly pick up Ele and we gather at Albert’s place, we secure the boat trailer to the car, and we hit the road. The ocean, once again, is calling.
We board a great little boat that is good enough to bring us to the outer reef where powerful oceanic currents bring food from the depth, fuelling the food chain. Little do we know that we are about to witness that very food chain in action.
We sail with a specific goal in mind: to spend some quality time at sea and swim in the crystal-clear blue waters of the Indian Ocean. What else do you need to be happy? What does it take to be the best day of your life?
When I was a kid, I saw a documentary about the remote town of Exmouth that rises from the colorful corals of the Ningaloo reef in Western Australia. I have been dreaming about this place for as long as I can remember. Finally, I can call Exmouth home and the Ningaloo reef has become my office.
We launch the boat from the jetty and we immediately have a good feeling about the day ahead. For once the forecast is not accurate: glassy sea, calm winds, beautiful weather, even a sea turtle comes to surface next to us as we head for the open ocean.
Suddenly, it all happened very quickly. Time flies when you are having a good time, and before we know it, we are a few miles from shore, and we follow the birds. I learned this trick in Iceland when I was working as a whale watching guide. Seabirds always gather around food, and chances are if birds are feeding from the air, something bigger is lurking below.
Bingo! There it is, a huge flock of birds, bomb diving and screaming above the surface. If you couldn’t see it, you would definitely hear it. We gear up and slip into the unknown waters below.
As soon as I put my head underwater, I realise that something special is about to happen right in front of my eyes. During the Arctic winter, I worked as a guide for the orca snorkelling expeditions in Norway. Orcas are incredible and unpredictable animals, but what I have learned is that you need to stay close to the bait ball, stay close to the food, and they will come to you. What I have in front of my eyes I have only seen in the most prestigious documentaries, and never would I have hoped to witness this with my very own eyes. Hundreds of thousands of bait fish swim in circles right in front of me in a defensive strategy meant to confuse predators.
Like an oasis in the desert, a bait ball attracts a number of species such as tunas, giant trevallies, barracudas and, of course, sharks. Dozens of sharks. Trying to capture such a hectic event is not easy. It starts very slowly, but before you know it, more sharks join the buffet, and it is hard to decide in which direction to point the camera. Perhaps the most bizarre thing about this event is the surreal silence that surrounds this brutal hunt.
Personally, I have always thought sharks were not very smart. Don’t get me wrong, they are faultless machines and magnificent predators, perfectly adapted to be on top of the food chain. The earliest fossil evidence of shark ancestors can be dated back to over 450 million years ago (that is before even trees existed on the prehistoric continents), but since then, they haven’t evolved much.
They represent an outstanding evolutionary success but I have always seen sharks as powerful animals, relying on their raw power, biting whatever they can without much thought or strategy. Yet here they are, taking turns and coordinating their attacks into the bait ball right in front of my eyes in a way that left me almost disorientated and definitely speechless.
When it comes to nature, you never stop learning and Poseidon seemed to have another surprise in store for us. Literally out of the blue, joining the buffet is a big, slow and hungry whale shark. With its friendly face and dotted suit, these gentle giants have become a symbol of Exmouth, with many people travelling every year to this remote corner of Australia to see them in their natural habitat. They are extremely common in the Ningaloo, but to find one feeding on a bait ball is not common at all.
Once again, theory and practice are not matching. I have always read that whale sharks are filter feeders, and they cruise the oceans looking for plankton. Here in the Ningaloo reef we had two coral spawning events in the last couple of weeks and that is exactly what they are looking for. The individual that came to visit us was a juvenile, just about six metres long. They can grow twice as big.
A young whale shark can eat up to 45 pounds (about 20 kg) of plankton every day. Right in front of us, it starts taking its bites, fully engulfed in thousands of fish, and then it would pop out on the other side of the bait ball. He would then turn around like a jumbo jet and go for it again, and again and again.
The salt water washed away the tears of emotions I shed about the epic encounter and about my personal long journey as marine biologist, diver and photographer that brought me to the right place at the right time. Swimming with this gentle giant has been one of the most incredible experiences of my life.
With the large whale shark around, it seemed like all the other predators, including the bull sharks, were starting to stay away and queue behind the whale shark. A good hour later, when the bait ball had shrunk and the whale shark disappeared into the deep blue, the hustle and bustle increased again.
At the end of the day, when the flock of birds had dispersed, and the bait ball had shrunk to the size of a watermelon, the last few sharks disappeared and we got back on the boat. At this point, the last few fish survivors were getting attacked by a few remaining tunas.
If you live in Exmouth, snorkelling in coral reefs and swimming in the ocean is as popular as going for a hike if were living in the Italian Dolomites. But when we got home and we show the raw footage to all our friends, looking at the expressions on their faces, we realise we saw something unique.
One question raised higher than the other: “Aren’t you scared? Isn’t it dangerous to swim with sharks?”. I personally never felt in danger while swimming in the water with these magnificent creatures. The truth is, the sharks were more scared of us than we were of them. Even though you need to pay them respect as they are predators, every time a shark came to check us out, he turned away quickly. They looked afraid of the human intruders. And for good reason.
According to latest data, humans kill around 100 million sharks per year. That is about 190 sharks a minute. Meanwhile, there have been only a total of 57 confirmed worldwide shark incidents in 2022. Unfortunately, regardless of these numbers, most people are still scared of sharks.
They are among the apex predators of the oceans, their presence regulates the whole food chain, from pelagic species to grazers all the way down to algae, and they have a massive impact on the entire ecosystem. Yes, they can be dangerous, and with some species being more aggressive than others you need to pay them respect, but as I always like to say, the oceans would be more dangerous without sharks.
Issue 30 Bleached
Issue 29 Moving sand
Issue 28 Sea forests
Issue 27 Mission Deep
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