WILD LIFE | 07.18.17
Good Luck Sharks
A spectacular aggregation of whale sharks brings good fortune to Indonesian fishermen—and attracts ecotourism dollars that may be the key to their survival.
Cenderawasih Bay, West Papua
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 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.
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.
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.
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.
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.
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?
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.
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.
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.
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.
ABOUT THE Photographer and Writer
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 byOutdoor Photography Magazine
as one of the 40 most influential wildlife photographers in the world. His work has been published in many international magazines includingNational Geographic, BBC Wildlife, International Wildlife, GEO, Smithsonian,
ABOUT THE Co-writer
Sophie Stafford isbioGraphic
's contributing photo editor and an independent communication and photography consultant for leading wildlife conservation charities, helping to inspire supporter engagement through visual storytelling. As editor ofBBC Wildlife Magazine
, she helped co-manage and judge the prestigiousWildlife Photographer of the Year
competition for nearly 10 years. Today, she joins the juries of many world-leading photo competitions.
Pete Oxford Sophie Stafford
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