"Blue. Nothing but blue. That's all I see when I look over the railing of our small boat. The ocean here, around the Azores and just above the Mid-Atlantic Ridge, is 800 meters deep. It's home to whales, rays, dolphins, tuna, barracudas—and sharks.
We're here to observe these predators up close and dive with them. Adrenaline. Anticipation. And also a queasy feeling. I feel everything at once.
Then he goes into the water.
To encourage the animals to approach the boat, our skipper repeatedly pours small amounts of fish blood (more information on this will be provided later) into the water. The current carries it directly toward me and the other expedition members. We lie snorkeling on the surface, in a cloud of blood and entrails, waiting to be surrounded by sharks. What's actually happening here?
Is it safe to dive with sharks outside the cage?
Before we get to sustainable diving tourism, we first need to clarify another issue. Despite what many people claim to the contrary, sharks are not bloodthirsty eating machines that attack everything that swims on the surface. The main reason we still believe this? We humans have often lost touch with nature.
In nature, it's all about survival. It's about risk management, cooperation, and efficiency. A shark that attacks anything roughly its size won't survive long in the ocean. A shark that carefully selects its prey, eats only what it needs to survive, and avoids unknown dangers has a much better chance of survival.
Of the more than 500 shark species found worldwide, almost all are considerably smaller than us. Only a few species are capable of seriously injuring a human. According to the International Shark Attack File (ISAF), nine people died in 2021 as a result of a shark attack. In comparison, approximately 1,000 people die annually from the much more aggressive and powerful crocodiles (CrocBITE). Moreover, although fatalities caused by sharks are extremely rare, they are often due to a lack of precautionary measures (more on this later) by humans.
"Back in the Azores, after about half an hour on the surface, a large shadow appears in the crystal-clear water below us. My heart rate quickens. The animal is shy and keeps its distance. It takes a few minutes before it dares to approach the surface. With its dark blue dorsal coloring, the shark is barely visible as it glides elegantly through the water. We remain calm and keep an eye on it. It becomes steadily more curious until it suddenly stalks us to within a few centimeters. It is a two-meter-long blue shark."
His curiosity often makes the shark its own prey
This behavior is often interpreted as aggression. In fact, it's just pure curiosity. And it's precisely this curiosity that actually leads to the sharks' downfall:
Approximately 100 million sharks lose their lives each year because their fins are sold in traditional Chinese medicine in Southeast Asia and because their meat is consumed worldwide (Worm et al. 2013). If you look closely, you'll also find shark deaths in our supermarkets: in cosmetic products, fertilizers, and even pet food.
Countless sharks also die from Longlines, in gill nets or trawls . The animals often die in Ghost nets – old, lost, or deliberately sunk fishing nets from industrial fisheries. Even the European Union is home to one of the largest shark fishing fleets in the world, overfishing shark populations throughout the Atlantic. According to the International Union for Conservation of Nature (IUCN), approximately one-third of all shark species worldwide are threatened with extinction. If this downward trend continues, many species will soon be extinct.
Sustainable diving tourism: hope for endangered shark species
There is still hope to stop the sharks from disappearing – for example through sustainable diving tourism.
A live shark that is dived with is worth much more than a dead one. In many countries, diving tourism is largely driven by shark and ray sightings. This not only benefits the diving industry, but also promotes the entire tourism sector in the respective region. In many regions, shark fishing is now prohibited for precisely this reason. The Bahamas, for example, have been a shark sanctuary since 2011 – precisely because hundreds of travelers dive there with the notorious predators every day. There are now 17 countries worldwide that have recognized their waters as shark sanctuaries. This corresponds to just over three percent of the surface of our oceans. The main reason for this is the profit from diving tourism. But this type of tourism is not always sustainable or ethically justifiable.
"The shark has now become accustomed to us. It repeatedly tries to exploit blind spots, but as experienced freedivers, my group and I are alert and keep an eye on what's happening around us. We avoid sudden movements so as not to scare the shark away. I descend. As a diver, I'm much more interesting to the animal. Suddenly, I'm moving with it in the three-dimensional space of its habitat. It spots me and heads straight for me. I maintain eye contact. We're at a depth of 15 meters, and I feel my breath running out. But surfacing hastily now would be a mistake. I wait for the interaction. We stare into each other's eyes for what feels like an eternity. The shark turns away. I surface."
The new shark diving industry is leading to the development of more and more dive sites. Over 85 nations now attract at least half a million travelers annually to shark dive. Therefore, dive tourism offers enormous potential for shark conservation. At dive sites, the predators are lured with bait to overcome their natural shyness. Without bait, it would be impossible to ensure interaction for divers. Unfortunately, standards regarding safety, sustainability, and ethics are often lacking. Expertise and experience are often lacking. The quality of a shark dive can sometimes fluctuate as much as an inflatable boat in high waves.
Certain standards must be met so that we actually do something good for the sharks instead of reinforcing their image as aggressive.
Shark feeding in sustainable diving tourism
The topic of baiting is controversial. Not all baitfish comes from sustainable fisheries, it can influence the animals' behavior, and ultimately, large predators come very close to humans. For example, a few hammerhead sharks in the Bahamas meet their entire energy needs through fed fish. Accordingly, their natural hunting instinct is suppressed (Heim et al. 2020). In the Maldives, tiger sharks appear at the dive site just minutes before food is released, as this happens at a similar time every day. Studies show that it can have a short-term influence on the sharks' movement patterns, but so far has not altered long-term migration patterns (Gallagher et al. 2015).
Nevertheless, baiting is a very effective method for shark conservation: Diving tourism increases the value of the animals and thus brings more money into the coffers of the local population. If the diving industry in the Bahamas were no longer allowed to attract sharks, sightings would be rare and by no means guaranteed. Demand for shark diving would likely decline quickly. This makes it more profitable to legalize the fishery again.
In other words, baiting is necessary to create a consistent and sustainable diving tourism around the sharks and thus indirectly protect them from extinction.
"I dive again. At a depth of ten meters, I hold my camera ready for a scenic shot of another diver with the shark. But a strange feeling comes over me. Something's wrong. I haven't looked back in a while. I glance over my shoulder. Suddenly, behind me, three meters away, there's another shark. It's smaller than the other one, about one and a half meters long. But it's brave. It's swimming straight toward me. I turn my upper body toward it to better maneuver. I decide to swim toward it. The shark keeps coming closer. But it's not aggressive. I realize it just wants to get past me, follow the trail of blood. A few centimeters from my face, I let the animal swim by. My mind is blank, no thoughts. Only the silence of the open blue, the sharks, and us freedivers."
Nonetheless, the interaction remains a provoked situation in which sharks expect to feed. They are designed to identify potential weak points in other animals and know exactly whether a person is paying attention and where they are looking. Sharks have a sense of whether or not they can risk a bite unnoticed. To avoid potential dangers, there are a few points to consider for sustainable diving tourism before jumping into the water with these animals on vacation.
- What attracts sharks? Fish blood is often used. Does the fish used come from a sustainable, local fishery, or is it industrially caught using unsustainable fishing methods (e.g., longlines, trawls, etc., which often also cause ghost nets)? Is the entire fish used, or are only the remains of a recycled fish used? Sustainable choices can be made here, too, and thus, for example, reduce the spread of ghost nets caused by fishing. It's best to ask the operators in advance where the fish comes from.
- How are the sharks attracted? Are the sharks actively fed, or is only the so-called "chum" released into the water? Chum is a mixture of chopped fish mixed with seawater, which is gradually released into the sea to create a blood trail to the dive site. Sharks have an excellent sense of smell, which allows them to detect blood traces from great distances. To minimize the impact on the animals' behavior and limit resource consumption, the animals should be attracted primarily with chum. This prevents the sharks from overfeeding, thus preserving their natural hunting instinct. At the same time, the blood trail can be maintained for hours with a relatively small amount of fish.
- What are the safety standards? A detailed briefing is a must, as is a minimum level of diving experience for all participants. Equipment should be shark-friendly: for example, you should dive in ninja gear (all black or dark blue) so that no contrast is visible to the shark. They're incredibly good at that.
It's clear that diving tourism can be sustainable if divers act appropriately. However, the welfare of animals and humans can only be ensured if certain standards are met. It's up to us to pay attention to this and keep ourselves fully informed. Only then can future generations experience the fascinating predators that inhabit our oceans.
Contribution by Lennart Voßgätter:
Lennart is a master's student in marine biology at the University of Bremen, specializing in the population ecology of tiger sharks. He has a passion for diving with sharks and spent five weeks in the Azores, a volcanic island group in the middle of the Atlantic, on a Bracenet scholarship. There, he studied and photographed the marine megafauna.
Sources:
Cisneros-Montemayor, AM, Barnes-Mauthe, M., Al-Abdulrazzak, D., Navarro-Holm, E., & Sumaila, UR (2013). Global economic value of shark ecotourism: implications for conservation. Oryx , 47 (3), 381-388.
Dulvy, NK, Simpfendorfer, CA, Davidson, LN, Fordham, SV, Braut, A., Sant, G., & Welch, DJ (2017). Challenges and priorities in shark and ray conservation. Current Biology , 27 (11), 565-572.
Gallagher, AJ, Vianna, GM, Papastamatiou, YP, Macdonald, C., Guttridge, TL, & Hammerschlag, N. (2015). Biological effects, conservation potential, and research priorities of shark diving tourism. Biological Conservation , 184 , 365-379.
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