Following rare attacks in the southern Red Sea this summer, Shark Trust patron Simon Rogerson explains why it is so important to respect each and every encounter with the oceanic white tip shark.
Listen to the banter on any Red Sea dive boat – you can bet a fair amount of it will be about sharks. A good shark encounter is a special memory, often the highlight of someone’s holiday, and the presence of certain sharks can be a sign of a reef’s health and productivity.
Most of Egypt’s sharks are naturally shy of divers, but the oceanic white-tip, Carcharhinus longimanus, is an exception. These sharks wander the deserts of the open seas, where food is scarce and every potential prey item must be keenly investigated. Where a grey reef or scalloped hammerhead shark would keep its distance after perhaps one curious pass of a diver, the oceanic will come in again and again, closer and closer.
Boldness – some would say aggression – is hard-wired into the oceanic’s behaviour. The trait has led to some memorable encounters at reefs such as Elphinstone, the Brother Islands and St Johns, where the recent fatal attack took place. At the time of writing it was too early to determine what exactly had prompted the attack, but it seems certain that the shark had been illegally fed.
All the predatory shark species become less predictable and more dangerous when their senses are stimulated by the presence of food. The scent of fish in the water ramps up their behaviour, so if the shark in question is already bold, it can become actively aggressive towards humans, which it may see as competitors.
The Red Sea is one of the last places you can dive with oceanic white-tips. They are sometimes seen off Hawaii, where they follow pilot whales, and on the outer banks of the Bahamas, but longline fisheries have massively reduced their presence in the Indo-Pacific. Just 20 years ago, they were the most populous large animal species on the planet, and now they are believed to be endangered. Their inquisitive nature has made them especially susceptible to longline fisheries, and their fins are prized by the Asian shark fin market.
For the most part, Red Sea encounters with Longimanus have been thrilling rather than threatening. I have spent long afternoons diving under liveaboards, watching the sharks as they patrolled between the reef and the boats. Every now and then, one would approach me head on, then veer gracefully away when I exhaled. It has been observed that the sharks tend to become increasingly aggressive the longer they investigate divers. The passes get closer, and the diver may even be bumped. This is the time to get out of the water, and it’s always worth remembering that a shark’s thoughts turn to feeding as the sun starts to set.
In the precious moments I have spent observing sharks, I have learned an important lesson… one that you will not read in any of the textbooks. Even within the same species, no two sharks show exactly the same behaviour. They can be shy, curious, fearful, confident, even gentle. As much as you try to predict a shark’s behaviour by its species, there will always be that unpredictable factor – its own personality. Accordingly, every shark encounter should be tempered with respect.
By Simon Rogerson
First published in BLUE magazine June 2009
Simon Rogerson is the editor of DIVE