It takes little more than two hours for the spotter planes to locate the first whale shark of the day. Along with the two-dozen or so others who have paid several hundred dollars to spend a day diving with the sharks, I don my mask and flippers in readiness to swim. We are halfway up the West Australian coast, just off Ningaloo Reef.
I am in the second group; strict licensing conditions prevent more than 10 people being in the water with a shark at any given time. When the moment comes, I jump in, swimming hard to catch up with our quarry. I see it quickly enough, a blue shape moving steadily through the water, cruising unhurriedly a metre or so beneath the surface. Like most of the whale sharks that congregate at Ningaloo it is a young male, approximately eight metres in length.
Wider and flatter than most species of shark, its shape is immediately recognisable by the width of its blunt head and its huge gaping mouth. The dark, grey-blue skin of its upper body is dusted with a complex pattern of pale, phosphorescent spots, which shimmer and dance upon it like the portholes of some wondrous ship. It is not easy to communicate the scale of the creature, which is exaggerated by its windsock mouth, more than a metre wide and close to two-thirds as high. This mouth seems to swell to contain the water that passes into it, disappearing into darkness, and is more than large enough for me or any one of my companions to swim into. Even its tail, which drives it forward with a steady, lazy motion, is almost as tall as I am.
There is a curiously docile presence about this shark. We are instructed to remain behind its eyeline, so as not to startle or distress it, but it gives little indication of concern about its human spectators, or even of a particular awareness of us. In part, this is due to our inability to read the complex social responses of marine creatures. It is also, I suspect, due to the whale shark’s particular biology and nature. Despite growing up to 12 metres in length, whale sharks are filter feeders; they subsist on a diet of plankton, krill and small fish such as sardines and anchovies, using their gill-rakers to sieve water.
Feeding in such a manner does not require speed – indeed, whale sharks are notoriously inefficient swimmers, using their entire bodies, rather than simply their tails, to propel themselves and travelling less than five kilometres per hour. Neither does it demand the restless predatory behaviours one sees in other sharks. Four years ago I spent several days diving with great whites and my abiding impression is that those creatures are possessed of a powerful, if deeply alien, agency; by contrast the whale shark, though equally alien, seems oddly benign.
Declared a marine park in 1987, Ningaloo is one of the few places in the world where whale sharks congregate in large numbers. Each year they begin to appear around March, attracted by the availability of krill and other food sources in the months following the annual spawning of the reef coral. Such concentrations of food are unusual, particularly in the tropical and sub-tropical waters favoured by the whale shark. Beyond this, the significance of the ecologically unique site of Ningaloo in the life cycle of these singular creatures remains largely unknown. Most of the whale sharks that come here are immature males, suggesting they are in the area to feed, not mate. Despite evidence that whale sharks can travel many thousands of kilometres, the relationship between the individuals at Ningaloo and populations known to exist in Indonesia and other parts of the Indian Ocean remains unclear.
Their behaviour presents further mystery. Whale sharks are believed to live for up to 100 years but we do not know how or where they breed (though the capture of an immature specimen near Pilar in the Philippines earlier this year suggests that area may serve as one breeding ground). This means that precise numbers and the vulnerability of various populations to overfishing or changes in habitat are difficult to assess. Some data suggests a population increase at Ningaloo, but the global whale shark population is under pressure from fishing and the ongoing degradation of tropical marine environments.
The only real certainty is that whale sharks are big business in Exmouth, the principal town near Ningaloo reef. Throughout the tourist season, a dozen boats are likely to be cruising the waters off the reef, waiting for spotter planes to report sightings. But Ningaloo’s whale shark tourism industry may be an example of ecotourism done right. Licenses are limited and strict regulations, drafted with reference to scientific evidence, govern the interaction between tourist and shark. The growing popularity of Ningaloo has also allowed for the development of a series of innovative, co-operative research programs that focus on identification of individual specimens. These programs, linking scientists and non-scientists, are generating valuable insights into the relationship between whale sharks at Ningaloo and other populations around the world.
Advocates of ecotourism would argue that many who journey here return with a more powerful appreciation of the complexity and wonder of the natural world. But watching the small flotilla of boats heading out from this otherwise deserted stretch of coast, I find myself wondering if this is always true. There is little doubt that Ningaloo is one of the most remarkable places I have been – its isolation and relatively undisturbed ecosystems a reminder of the narrowness of our anthropocentric perspective – yet, for many, the focus of the whale shark experience seems to be about ticking them off a list of sights to be seen, something that serves not only to diminish them, but also, by extension, ourselves.
