'Oceanic Odyssey'

Diving with Oceanic Whitetip Sharks at Cat Island in the Bahamas

First published in Diver Magazine November 2011

Teetering on the very edge of the continental shelf, it is not surprising that Cat Island attracts mega fauna seldom seen elsewhere in the Caribbean.
From monster marlin to massive mahi, Cat Island is an important pit stop for apex predators plying the western Atlantic in search of a meal.
Although Cat was discovered generations ago by sport fishermen looking for record breaking animals, tales of hooked billfish being mobbed by hungry sharks only recently came to the attention of the international diving community.
Once the word was out, divers began dropping into three thousand feet of clear blue offshore water to swim with one of the ocean’s most notorious inhabitants: Carcharhinus longimanus, more commonly known as the oceanic whitetip shark.

Intrigued by the prospect of an encounter with a shark that few divers have seen this side of Africa, I hopped on a puddle jumper from Nassau and boarded Epic Diving’s Atlantic Explorer.
Barely ten minutes after leaving the marina, the sea floor fell away into the abyss, which was our cue to start chumming for oceanics. Accustomed to the slow process of attracting pelagic sharks, I was surprised to watch the Captain revving the engines and throwing the converted sport fisher into tight turns and circles.
He explained that the sharks are instantly attracted to the jerky sounds of the engines because they mimic a sport fishing boat that is fighting a game fish.
Revving the engines is particularly effective because it attracts sharks from every direction whereas a chum slick by itself produces a linear scent trail that the sharks must stumble across before they become interested.

The Captain’s aural ruse was immediately successful. The first frosted dorsal fin materialized like a snow capped peak slicing magically through the water.
I slipped in with snorkel and fins. The oceanic swam boldly towards me and we spent a brief moment appraising each other.
I was in the presence of a two meter female. Her coloration was like no shark I had ever seen and I was utterly captivated by her golden hide that gave way to a layer of subtle stippling on her lower flanks and then faded seamlessly into the creamy counter-shading of her belly.
Her broad, ivory tipped pectoral fins and powerful heterocercal tail appeared perfectly adapted to provide effortless lift and maneuverability on long ocean voyages. Like a glider riding thermals, she could face into the current and hold position or be swept downstream with virtually no energy expenditure.

Her catlike pupil and freckled iris flicked back and forth uncertainly in my direction but her body language betrayed no signs of malice. Before long, she returned to her slow exploration of the bait crates but came back to visit me regularly.
Over the next six hours, more oceanics made their way up the irresistible chum trail. All were mature females and I was reassured to see that some were close to term.
One large individual was flanked by an entourage of vertically striped pilot fish that would dart away to pluck scraps from the water column before returning to the safety of ‘the mother ship’.
At one point, a confused pilot fish fell into step beside the wrong shark, then did a comical about-face and swam at lightning speed back to its original host. One can only assume that certain sharks have developed a taste for pilot fish.
No sharks showed any aggression towards me or the other divers that had joined me at the back of the boat, but when a 4ft mahi mahi (Coryphaena hippurus) entered the fray, the sharks became visibly agitated. It was clear that the erratic movements of a natural prey species triggered a strong hunting response that the presence of humans and even the bloody chum slick did not.

At the marina the next morning, I bumped into Ed Brooks from the University of Cape Eluethra. Ed was finishing up a scientific expedition that had placed tags on eleven whitetip sharks.
He explained that virtually nothing is known about the migratory patterns of western Atlantic oceanics other than the fact that they arrive off Cat Island in early April and are gone by the end of June. He hopes that when the satellite tags pop to the surface later this year, he will be able to trace their progress and perhaps even figure out what they are following.
Ed is also working on a photographic database of individual oceanic whitetip sharks that he hopes divers will embrace and contribute to. The database employs the same stellar mapping software that is used to identify and track whale sharks on their global migrations.

Listed by the IUCN as critically endangered in the western Atlantic, the oceanic whitetip shark has become the unfortunate poster child of shark conservation movements.
A 2005 paper on the decline of pelagic shark populations in the Northwest Atlantic by Dr Julia Baum and the late Ransom Myers, states that C.longimanus stocks in the Gulf of Mexico have been reduced by a staggering 99% with silky sharks not far behind.
For decades, oceanics have been taken for their meet, skin and oil but it is their long spatulate fins that make them such a desirable catch.
Convincing fishermen to leave the sharks alone is a tough sell when the fins fetch upwards of $85 per kilo on the international market.

Its an uphill battle that is hindered by the sharks’ fearsome reputation. Dubbed the wolves of the ocean, whitetips have a history of capitalizing on the misfortune of shipwrecked sailors and downed airmen.
An unforgettable example of their opportunistic behavior occurred in the summer of 1945 when the USS Indianapolis (on its way home from delivering parts for the atomic bomb that was later dropped on Hiroshima) was torpedoed by a Japanese submarine.
Nearly 900 hapless sailors leapt clear of their doomed vessel only to face four harrowing days immersed in the Pacific awaiting rescue. During their ordeal, the men fell victim to exposure, dehydration and shark attacks. Oceanics were implicated as the most likely culprits but it is unclear how many of the 560 men that perished in the water were actually taken by the gathering mass of sharks.

Our next day with the oceanics was as fin-filled as the first. Following the recommendations of a local sport fisherman (who was more than happy for us to keep the shark population busy) we headed to an area off the exposed east side of the island and started ‘pulling doughnuts’ with the boat while a greasy finger of fish oil snaked away down current.
When a whitetip shark appeared in record time we named the new site ‘Oceanic Express’.
Five hours later, I had images from so many angles that I decided to switch off my strobes and just hang on the tag line until it was time to leave.
Oceanic Express turned out to be our most productive site of the trip with multiple sharks ready to play and fly-bys of marlin, mahi and even a baby tiger shark.
In spite of their reputation, the oceanics were on their best behavior through every encounter and I was left with the conviction that until we start putting protection before profit, we will remain far more of a threat to the sharks than they are to us.
 

Andy Murch is a Photojournalist and outspoken conservationist specializing in images of sharks and rays.

About Cat Island:
Although Cat is the tallest of The Bahamas 600+ islands, at 206ft you should leave your skis at home.
Much of the coastline is covered in mangrove but there are many quiet beaches, all of which have healthy fringing reefs.
Far from the maddening crowds, Cat Island has a handful of small resorts including Hawksnest (hawks-nest.com) which also boasts the island’s only marina.

Getting there and away:
Cat Island’s New Bight Airport (TBI) is serviced twice daily by Sky Bahamas from Nassau (NAS) and less frequently by Continental and Lynx Air from Fort Lauderdale.
 

Shark Encounters and Reef Diving:
http://bigfishexpeditions.com/OceanicWhitetipSharkExpedition.html