The Oceanic WHITETIP SHARK

About Guy 

The big shark quickly approached me near the calm surface. The sunlight dappled its back and fins as its tail oscillated back and forth in wide sweeps, its head swaying from side to side coming closer and closer. There was no hesitation. Its wide fins looked like wings of a jet coming in to land.

Suddenly it was on me and investigating my camera. It moved around me in a tight circle, testing the camera housing with its nose and I kept turning with the big eight foot long animal, getting great footage. It then turned away and went to check out the other divers in the group.

This was my introduction to the notorious ocean whitetip shark.  Once considered by Cousteau too dangerous to dive with outside of a cage, this species has recently been at the centre of attention of a lot of photographers and scientific research as it has become increasingly scarce. According to marine scientists in the 1960s the whitetip was the most abundant large animal on the planet with cosmopolitan distribution in tropical seas.

In the Gulf of Mexico the population level was recently calculated at one per cent of its pre-exploitation level. Long line fishing and an indiscriminate fishing practice conducted by many countries in international waters, has taken its toll on this species. Because of their oceanic existence, large size and fins and the once large population, oceanic whitetips have quickly plummeted to extremely low levels and are now listed as “critically endangered” by the International Union for Conservation of Nature.

Oceanic whitetips are characterised by a robust mottled gray-brown body growing up to ten feet long with long, broad pectoral fins tipped in dirty white as are the pelvic fins and tail. They live near the surface of the open ocean, constantly cruising along looking for a food source and will investigate anything floating whether it is floating weed, flotsam or debris in search of a feeding opportunity. They cover vast distances between feeding opportunities.

They prey upon squid, fish and a variety of carrion including humans. When this animal sensed my presence in the water it quickly swam up to investigate me.

In the Cayman Islands we don’t encounter this shark on a typical wall dive. They are often seen offshore in April, May and June as they follow schools of migrating dolphin fish (mahi mahi) and tuna as well as some species of toothed whale, like pilot whales. Fishermen will usually encounter whitetips while out fishing for dolphin. Unfortunately many of these encounters result in the demise of this shark as fisherman here are not aware of how rare this species has become.

Their predicament has been highlighted by the Cayman Brewery (Caybrew), a local company that has named a product after the species and generously donates five cents from the sale of each can/bottle toward shark research work being conducted by the Department of Environment. Here is a classic example of how a private sector business has become involved with an important conservation issue and is DOING something about it. So drink White Tip beer and support shark research and conservation here in the Cayman Islands.

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For my part, the Guy Harvey Ocean Foundation is sponsoring research on the migrations of this species by providing hi-tech electronic tags to be deployed on this species.  Kirk Freeport has now kindly stepped up and is supporting this project. The track of one whitetip called “Chris”, caught off East End, has shown how this shark spent most of its time during a year in the western Caribbean (often near these islands) before heading out to the western Atlantic.

The foundation is also tagging whitetips in the Bahamas. One track beginning off Cat Island shows how a particular shark migrated along the chain of islands in the southeast Bahamas but exhibited site fidelity to Cat Island. There is an area of local abundance for this species in the southeast Bahamas because 20 years ago the Bahamas banned long line fishing. In addition, in 2011 the government of the Bahamas issued protection for all sharks from commercial exploitation.

The Stonybrook University of New York has done extensive research on this species in collaboration with the Cape Eleuthra Marine Lab, Bahamas, over the last two years and will be revealing a great deal about the life history of this high seas wanderer of the western Atlantic Ocean.

This dolphin season, if you see an oceanic whitetip shark under flotsam or one approaching a fish you have hooked, please do not harm the shark as there are very few left.  We still await protection for all species of shark here in the Cayman Islands. Contrary to popular belief, the most recent shark population survey indicates that overall numbers of sharks here are very poor and they need our protection.

The National Conservation Law, if given a chance by the procrastinating politicians of three successive administrations, will cover this and many other species in well needed legal protection.

It is our collective responsibility to conserve the marine environment and maintain the biodiversity of this planet.

Fish responsibly, dive safely.
 

 

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