Bus un­der wa­ter

Driven by a love of the sea and its largest fish, the elu­sive whale shark, Aus­tralian nat­u­ral­ist Brad Norman has cre­ated a world­wide photo-iden­ti­fi­ca­tion sys­tem which en­ables or­di­nary peo­ple to as­sist in its con­ser­va­tion. JU­LIAN CRIBB re­ports

Townsville Bulletin - - Weekend Extra -

BE­FORE the swim­mer’s eyes, glow­ing flecks shine like stars eerily trans­posed into the depths of the sea.

Through a blue-dark veil of wa­ter, a huge shape grad­u­ally re­solves it­self, ris­ing slowly and ma­jes­ti­cally to the sur­face.

Af­ter hun­dreds of sight­ings, Brad Norman’s blood still thrills as the great, spot­ted whale shark comes into view, glid­ing ef­fort­lessly for­ward, its pale, me­tre-wide mouth agape to scoop up thou­sands of litres of pro­tein­rich sea wa­ter.

‘‘When they are down deep, they re­sem­ble a starfield un­der wa­ter,’’ he says. ‘‘As you swim above, the shark’s body seems to dis­ap­pear and its white spots light up like stars in the night sky. It’s an awein­spir­ing sight.’’

The 38-year-old Aus­tralian nat­u­ral­ist has ded­i­cated most of his adult life to the pur­suit, iden­ti­fi­ca­tion, un­der­stand­ing and pro­tec­tion of the world’s largest fish, Rhin­codon ty­pus, the aptly named whale shark.

Reach­ing 18m in length, the huge beast re­sem­bles noth­ing so much as ‘a bus un­der wa­ter’, Norman says.

Yet an an­i­mate, placid, oc­ca­sion­ally in­quis­i­tive bus, pur­su­ing its mys­te­ri­ous life across tens of thou­sands of kilo­me­tres of open ocean.

First recorded in 1828, only 350 whale-shark sight­ings were recorded in the en­su­ing 150 years.

Re­cent growth in un­der­wa­ter tourism has brought a surge in sight­ings. Yet the whale shark re­mains elu­sive, and the World Con­ser­va­tion Union (IUCN), which en­gaged Norman to as­sess the species, re­gards it as ‘vul­ner­a­ble’ to ex­tinc­tion.

It is pro­tected in only a hand­ful of coun­tries.

Brad Norman is de­ter­mined to find out far more about th­ese fish.

His vi­sion­ary plan to in­volve thou­sands of or­di­nary peo­ple world­wide in the pho­tomon­i­tor­ing and con­ser­va­tion of whale sharks, sig­nif­i­cantly en­hanc­ing knowl­edge of this elu­sive species, has earned him a 2006 Rolex Award for En­ter­prise — the first Aus­tralian re­cip­i­ent in 25 years.

The whale shark is one of only three sharks that are fil­ter- feed­ers, us­ing gill rak­ers to scoop up krill (shrimp), small fish and other tiny ocean life as its sole source of sus­te­nance. It has never been known to at­tack hu­mans. Tagged in­di­vid­u­als have been tracked for 13,000km across the Pa­cific, and 3000km in the In­dian Ocean. It has an un­canny in­stinct for lo­cat­ing food con­cen­tra­tions.

It is sighted at more than 100 places around the globe. Yet it re­mains so scarce al­most noth­ing is known of its abun­dance, breed­ing habits or habi­tat pref­er­ences.

It has few nat­u­ral en­e­mies, though or­cas and preda­tory sharks may at­tack young whale sharks. Now, how­ever, the whale shark has joined the long list of species to suf­fer the in­sa­tiable hu­man ap­petite for seafood.

Its flesh, fins and body parts are ap­pear­ing in grow­ing quan­ti­ties in Asian mar­kets where they fetch $US18/kilo­gram or more.

Since his first awed en­counter in 1994, in West­ern Aus­tralia’s Nin­ga­loo Marine Park, Norman has striven to un­cover all he can about this lordly an­i­mal, whose an­ces­try ex­tends back 400 mil­lion years.

‘‘My first en­counter seemed quite sur­real,’’ he says.

‘‘There was this huge, liv­ing thing com­ing di­rectly to­wards me. My eyes were pop­ping out of my head. I al­most swal­lowed my snorkel. I was scream­ing silently to my­self in ex­cite­ment.

‘‘Yet, oddly, I wasn’t afraid. I just floated there, too amazed to swim af­ter him.’’

As his en­coun­ters mul­ti­plied, Norman grew to ap­pre­ci­ate many as­pects of the whale shark.

Its eco­nom­i­cal 1-1.5m per sec­ond cruis­ing speed was per­fect for ob­ser­va­tion. Though able to dive as deep as 1500m, it of­ten swam con­ve­niently near the sur­face.

Its placid tem­per­a­ment made it safe com­pared with other big sharks. Yet it could also be dy­namic: ‘‘I once ob­served seven in an area where there was a huge swarm of krill, a real soup of food in the wa­ter. They were charg­ing through it, mouths open, thrash­ing around. That was a big adrenalin rush. I never felt fright­ened, but I did keep my arms down and made my­self small.’’

‘‘Even with some­thing as big as a whale shark, you’re not afraid — and nor is it. It is a calm­ing ex­pe­ri­ence. You feel at one.’’

Norman has mounted na­tional and in­ter­na­tional cam­paigns for the whale shark’s con­ser­va­tion, emerg­ing as a global ex­pert on the an­i­mal and its needs.

Fol­low­ing a clue pro­vided by an ex­pe­ri­enced fish­er­man, Norman’s painstak­ing re­search man­aged to prove that ev­ery whale shark has a pat­tern of white spots on its body as in­di­vid­u­ally dis­tinc­tive as a hu­man fin­ger­print. This gave him the idea of us­ing un­der­wa­ter cam­era images as a prac­ti­cal, non­in­va­sive way to iden­tify in­di­vid­u­als. In 1999 he set up the ECO­CEAN Whale Shark Pho­toiden­ti­fi­ca­tion Li­brary on the In­ter­net, a global project to record sight­ings and images.

De­spite the grow­ing body of in­for­ma­tion, Norman lacked an ef­fi­cient way to com­pare shots of whale sharks.

In 2002, a US com­puter en­gi­neer and fel­low diver Ja­son Holm­berg con­tacted him, of­fer­ing to help or­gan­ise and au­to­mate the ECO­CEAN data­base.

He ex­plained the photo-ID prob­lem to a friend, NASAaf­fil­i­ated as­tronomer Zaven Ar­zou­ma­nian, whose col­league Gijs Nele­mans pointed out that a tech­nique used by Hub­ble Space Tele­scope sci­en­tists for map­ping star pat­terns known as the Groth al­go­rithm, might also be use­ful for recog­nis­ing whale sharks by map­ping the unique pat­terns of white spots on the shark’s hide.

It took many months of cal­cu­la­tions and com­puter pro­gram­ming to re­fine the al­go­rithm for use on a liv­ing crea­ture — but they gained a break­through for bi­ol­ogy: a re­li­able way to iden­tify in­di­vid­u­als in vir­tu­ally any spot­ted an­i­mal pop­u­la­tion, with­out tag­ging or ha­rass­ing them.

Or­di­nary peo­ple can take part in real science on ECO­CEAN.

Their pho­tos are au­to­mat­i­cally cat­a­logued, com­pared and, if pos­si­ble, iden­ti­fied as be­long­ing to a known in­di­vid­ual. Each new im­age helps Norman com­pile a global map of where whale sharks live and their mi­gra­tory pat­terns.

Con­trib­u­tors re­ceive no­tice by email of all past and fur­ther sight­ings of ‘their’ shark.

To­gether, the images are help­ing to build a global pic­ture of the whale shark pop­u­la­tion.

With the Rolex Award money, Brad Norman is de­vot­ing two years full-time to his project, train­ing lo­cal au­thor­i­ties, tourism op­er­a­tors and 20 re­search as­sis­tants around the Pa­cific, At­lantic and In­dian oceans to ob­serve, record and pro­tect whale sharks.

‘‘It is a big, beau­ti­ful and charis­matic an­i­mal, and not dan­ger­ous,’’ he says.

‘‘It is a per­fect flag­ship for the health of the oceans.’’

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