Wild Life

Good Luck Sharks

A spectacular aggregation of whale sharks brings good fortune to Indonesian fisherman—and attracts ecotourism dollars that may be the key to their continued survival.

It’s a perfect night for catching fish. Glossy, ink-black waves lap gently around the fishermen’s floating platform. Brilliant electric lights lashed to the structure’s sides make the platform look more like an all-night party boat than a fishing vessel. As the artificial glow illuminates the dark ocean water, it catches countless flashes of silver shimmering in the depths.

A fisherman peers down at the shoal of baitfish gathering beneath the platform, lured by the light. Tonight’s haul will be good, he thinks, thanks to his lucky charm. At the edge of the beam, a shadow moves towards the platform. A cavernous mouth with pale lips, seemingly large enough to engulf a small car, gapes open. A living talisman surfaces.

The largest and arguably most magnificent fish in the sea can reach a staggering 12 meters (40 feet) in length and tip the scales at 18 metric tons. Despite its colossal proportions and the relative ease with which it can be observed when it gathers in large breeding aggregations, scientists know surprisingly little about this spectacular creature.

The whale shark (Rhincodon typus) is indeed a fish, not a whale: It breathes through gills, is cold-blooded, and possesses a skeleton made of cartilage. The “whale” portion of its common name is a reference to the animal’s immense size and manner of feeding, rather than any close relation to marine mammals. While these gargantuan diners could swallow much larger prey, they eat mostly minute plankton as well as small fish and squid that blunder across their path. The sharks sieve these organisms from the ocean in the same way that baleen whales do, cruising near the surface, sucking in huge mouthfuls of water and the precious nutrients it contains. Curiously, whale sharks have more than 3,000 tiny teeth, aligned in bands that look like rough metal files, inside their impressively wide jaws, but evolution has long since abandoned whatever function the teeth once served.

Unlike air-breathing mammals, whale sharks can stay under the surface and out of sight indefinitely. Their penchant for long-distance ocean travel, often at great depth, makes them incredibly difficult to find, and to study. As a result, scientists know very little about the species’ most basic life history. It is estimated that whale sharks mature at around 30 years of age and may live more than a hundred years. But they have never been seen mating, nor have their birthing grounds been identified. With so little information, it’s difficult to know which areas of the ocean are most critical to the longevity of the species and therefore what the conservation priorities should be.

A whale shark cruises beneath the surface, its outline bathed in refracted light.

The Coral Triangle, home to more than three-quarters of the world’s coral species and more than a thousand species of fish, is the underwater equivalent of the Amazon rainforest in terms of biodiversity. It encompasses an area half the size of the United States, and its warm, nutrient-rich waters harbor more marine species than anywhere else on the planet. At the Triangle’s southeastern corner, off the Province of Papua and West Papua, is Cenderawasih Bay. Covering slightly more than 14,000 square kilometers (5,400 square miles), this is Indonesia’s largest national park—and the location of one of the world’s most spectacular aggregations of whale sharks.

Here, in this ancient sea, an extraordinary relationship has developed between local fishermen and a population of curious and opportunistic whale sharks.

Traditionally, local fishermen have regarded the species with great respect. They believe these gentle giants bring good luck, and so, for decades, they have tossed the sharks fish scraps in the hope of keeping the behemoths—and the good luck they bring—close by. In recent years, with the growth of marine tourism, this relationship has developed a new and potentially rewarding facet—one that stands to benefit both the fishermen and the whale sharks.

Cenderawasih fisherman camp out for days, even weeks, on large, hand-made, floating platforms, known locally as bagans. The structures are little more than a rustic assemblage of bamboo poles, electric cables, light bulbs and nets, anchored to the seabed. During the day, the fishermen take turns eating, sleeping, and fixing nets. As night falls, the serious business of fishing begins.

The fishermen use generator-powered lights to attract squid and small silverside baitfish, known as ikan puri, to large nets suspended below the bagan. When the fishermen are satisfied with the number of fish congregated between the net and the platform, they raise the net, trapping a shimmering, shivering ball of fish. When the fishing is good, they might make several hauls in a single night.

As the fishermen begin pulling in their nets, whale sharks seemingly materialize out of nowhere beneath the bagan, lured by the activity and the scent of fish in the water. Some of the smaller baitfish squeeze out through the mesh of the net and are immediately scooped up by the gaping mouths of the sharks. Occasionally, the hungry diners will suck the fish right out of the net. Fortunately, the fishermen don’t seem to mind. Indeed, encouraged by the additional revenue generated by foreign tourists wanting to witness this spectacle, the fishermen actively encourage the sharks to stick around by pumping a stream of water laden with fish oil and scrap parts over the edge of the bagan.

Bagan fishermen have long considered whale sharks to be good luck charms, and keep them around by regularly tossing fish scraps into the water.

This special relationship offers an unrivalled opportunity for divers to swim among whale sharks—and I traveled halfway around the globe for the experience. Slipping into the water with my camera, I positioned myself as close as possible to the gentle stream of fishy water spilling into the ocean. As I watched, one, two, then three whale sharks moved in and hovered vertically in the water next to me as they jostled for the best position, their huge mouths agape under the cascade.

Periodically, another individual would sneak up from behind and gently nudge me out of the way to get in on the action. In general, though, I was struck by the whale sharks’ astounding sense of situational awareness. They seemed to know exactly where I was, and, oddly, to treat me with incredible respect.

As I swam in the open ocean, away from the bagan, the sharks would often cruise past me at high speed—flying through the water like speckled submarines. At the last moment, they would gently flex their enormous tails to avoid contact, their bodies arcing within feet of my own. Occasionally, an individual would follow as I drifted farther away from the bagan, swimming in circles around me, apparently curious about this strange being in its home. Each dive, I would spend as much time as the air supply in my scuba tank would allow, enjoying these one-on-one encounters that made me feel like the shark and I were the only two animals on the planet.

Occasionally, these intimate moments would be interrupted when one of the fishermen from the bagan splashed in, goggleless, to join in the fun. It was always a pleasure to see the fisherman’s face light up with the same delight I felt.

Nearly all of the whale sharks we encountered around the bagans were juvenile males. This is clearly not a breeding population—it’s a boys’ club.

A dramatic skew toward young males is common at most known whale shark aggregations around the world. But these types of coastal gatherings are generally seasonal occurrences. Whale sharks are highly migratory, traveling far and wide and turning up in such places as Ningaloo Reef in Western Australia, Gladden Spit in Belize, and Isla Mujeres in Mexico to feed on krill blooms or the egg bundles from the mass spawning events of corals or reef fishes.

The whale sharks in Cenderawasih Bay seem to be unique in that they are found here year-round. They appear largely content to put aside their innate migratory tendencies and stay put, gorging themselves on the abundant silverside baitfish. After all, why make a long journey when there’s an all-you-can-eat buffet at home?

A young male whale shark feeds on small pieces of fish that escape through the mesh of the fishermen’s nets.

Being here, surrounded by dozens of young male whale sharks, it’s hard not to wonder where all the females, adult males, and their babies are. Where do whale sharks mate? Where do they give birth? To begin to answer these questions, researchers from Conservation International and the Georgia Aquarium have placed satellite tags on whale sharks in various locations around the world, including Cenderawasih Bay.

Based on data collected from these tags, the scientists have concluded that most whale sharks spend the majority of their time in deep waters. Even the young males that gather at seasonal feeding locations, where they attract hordes of snorkelling tourists, spend most of their time below 60 meters (200 feet), and frequently more than a thousand meters (3,280 feet). In fact, one tagged whale shark was recorded at a depth of more than 1,800 meters—more than mile below the surface. It seems likely that the females and adult males also spend their time roaming the ocean at these remarkable depths, where they would be all but impossible to observe.

Despite many as-yet unresolved questions, scientists working in the Galápagos think they may have discovered where at least some whale sharks give birth. Experts from The Charles Darwin Research Station and Galápagos National Park think that the northern isles of the Galapagos archipelago could be an important breeding ground for the species. Here, divers regularly encounter very large adult females between July and October—and many of these individuals appear to be pregnant. Whether this is, in fact, a breeding and birthing ground for many, or most, whale sharks is still unknown, however.

In Cenderawasih Bay, the whale sharks’ reliable year-round presence makes them the focus of a small but growing tourism industry. Dives among groups of whale sharks feeding around the bagans offer adventurous eco-tourists an unforgettable experience, while providing vital and sustainable income to local people. Both the fishermen and their communities benefit from fees dive operators pay to keep the whale sharks here and accessible to their clients.

This experience is unique among whale shark dives. In many other locations, the sharks zip past as snorkelers spill out of boats, hoping for a fleeting encounter. Here at Cenderawasih Bay, we don’t see another boat during our entire visit, and we are fortunate to spend many hours in the water with these massive fish to ourselves.

But we also learn that not all of the whale sharks’ interactions with people here are positive. Some of the individuals we encounter have deep scars on their snouts. Whether these were cuts from a machete (perhaps to discourage the sharks from pilfering fish) or wounds from having plowed into the cutting strands of oceanic drift nets is impossible to know.

A free-diver swims alongside a whale shark in Cenderawasih Bay, Indonesia.

In some parts of the bay, the whale sharks are also beginning to test the strength of their partnership with local fishermen. Increasingly, overly excited individuals, not content to wait outside the nets for a free meal, are swimming right into them as the fishermen lift the nets from the water. While there are typically plenty of volunteer rescuers around to free the animals in these instances, this behavior puts both the sharks and the fishermen at risk, and threatens to sour the relationship between the two. Fortunately, local people are keen to find a solution, and are working with conservation biologists to modify the net design in a way that prevents even rambunctious sharks from entering.

Tourists can present a threat as well. With more divers come more boats, and this increase in traffic puts the sharks at risk of boat and propeller strikes. To prevent problems before they occur, biologists from Conservation International and other organizations are working with officials from Indonesia’s Ministry of Maritime Affairs and Fisheries to develop whale shark tourism guidelines. These codes of conduct, which specify a minimum approach distance for vessels, should help to reduce injuries and stress to the sharks, and ensure the sustainability of this remarkable relationship.

While I had many amazing experiences in Cenderawasih Bay, my final few hours with the sharks were the most memorable. As I was once again observing the feeding fray, a large male approached from behind, his mouth agape. As he moved toward the surface, I could feel my entire body being scooped out of the water, perched on top of the shark’s nose. Seconds later, I was gracefully lowered back down. The shark and I made eye contact, and I couldn’t help wondering if he was as surprised as I was by what had just happened.

Then, as I edged away, I watched as a new subadult male arrived on the scene. The youngster was surrounded by a brilliant bouquet of golden trevallies (Gnathanodon speciosus), small fish that frequently “pilot” the sharks by swimming just a few inches in front of their mouths. These two encounters in quick succession without a doubt made for one of my best-ever wildlife experiences.

Moments like these have the power to change attitudes and behaviors. While the impacts of a growing ecotourism industry on whale sharks are still unknown, I firmly believe that as long as encounters like these are conducted in a controlled and respectful manner, giving people the opportunity to see these gentle giants, either in person or in the photographs that result, will ultimately help to protect these amazing animals.

The Threat of Shark Finning

The Coral Triangle is a priority for international conservation, but pressures on the area are intense. A host of problems, including overfishing, practices such as cyanide and dynamite fishing that cause long-term reef damage, coastal development, and climate change are all taking their toll on the ecosystem and its biodiversity.

Sharks face yet another threat that has the potential to wipe out entire species, including whale sharks: shark finning. Shark fins are one of the most highly valued marine products in the world. They are sold to the restaurant trade and exported to Singapore, Taiwan, Hong Kong, Malaysia and China, where they are consumed as shark fin soup at important events. Indonesia is arguably the number-one supplier of shark fins around the world.

The whale shark’s massive fins, skin and liver oil are highly prized. But whale sharks cannot replenish their numbers under heavy fishing pressure because of the species’ long life span, slow reproductive rate, naturally low abundance, and highly migratory nature.

The global population of whale sharks is believed to have declined by more than 50 percent over the past 75 years. As a result, the International Union for Conservation of Nature now lists the species as Endangered.

In 2013, the Indonesian Government declared the whale shark a fully protected species, due to its economic value for tourism. However, with some 17,000 Indonesian islands and a vast coastline, enforcement is a significant challenge that will require an ongoing investment of resources. Income from a growing ecotourism industry could help to fund this work.

Pete Oxford

Pete Oxford was a founding member of the International League of Conservation Photographers. He was awarded Ranger Rick Photographer of the Year and Ecuador’s Photo Journalist of the Year in 2015, and was recognized by Outdoor Photography Magazine as one of the 40 most influential wildlife photographers in the world. His work has been published in many international magazines including National Geographic, BBC Wildlife, International Wildlife, GEO, Smithsonian, and Nature’s Best.

Sophie Stafford

Sophie Stafford is an independent communication and photography consultant for leading wildlife conservation charities, improving supporter engagement through visual storytelling. As editor of BBC Wildlife Magazine, she helped co-manage and judge the prestigious Wildlife Photographer of the Year competition for nearly 10 years. Today, she joins the juries of many world-leading photo competitions.

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