Dangerous or the dive of your life? Taking a closer look – what do we really know about the Bull Sharks at Sail Rock?

Divemaster Deb follows up on the Bull Sharks at Sail Rock and asks if they really are dangerous? 

Image courtesy of Vladimir Radnic, Haad Yao Divers (Instructor)

A few weeks ago I wrote about the Bull Sharks at Sail Rock. At the time I had seen one small shark at a distance of approx. 20m. In the past few days I and many other divers have come within 2m of the sharks. With dive boats filled with enthusiastic divers traveling in numbers from Koh Samui, Koh Phangan and Koh Tao in search of the Bull Sharks, Sail Rock has become a busy spot and one of the ocean’s top predators is becoming more and more curious underwater.

In the first few weeks of the Bull Sharks sighting’, keen eyed divers were able to recognise their shadow and form as they smoothly swam past in the blue. In the past week or so the photos and videos have become increasingly clearer as divers are almost coming face to face with the sharks as they circle the reef and come within 2-3m range of it.  No longer a case of ‘spotting’ the Bull Sharks, almost every diver ascending at Sail Rock these days has their own experience of ‘diving with sharks’.

National Geographic Newswatch Image

When I was guiding at the site recently I saw nine sharks in total; four on my first dive and five on the second dive. It is difficult to say if they were the same sharks or different ones but I think it is fair to say that there is a school of Bull Sharks, male and female, ranging in size from 2-4m. Almost one month since the first sighting of the Bull Sharks, they are very much ‘present’ at Sail Rock now. In the past four weeks that they have been at the reef thousands of divers have had the experience to come up close to these 400 million year old creatures. Understandably, the atmosphere at the site has been greatly affected by the presence of the Bull Sharks.There is a palpable sense of excitement as people swim to the rock to make their descent. Once underwater, many divers make their way to the ‘the spot’ – Batfish Pinnacle and the Northern corner to patiently wait for the ‘fins’.

At ‘the spot’ on my recent dive I had the good fortune to see the Bull Sharks at a distance of approx. 10m with 25m visibility on my first dive. I saw two pairs swim past and later circle the pinnacle, witnessing their full splendour and girth for about 15 mins as their fins cruised past. Feeling very satisfied by this experience we made our way closer to the reef and turned for home. Keeping our eyes to the blue we suddenly saw another pair, approx. 2-3m in length circling next to us at 2m. At 12m I could see clearly into the cold dull eyes of the Bull Shark as it’s head pointed straight to me. In mid-water with excellent visibility and a bottom depth of 30m the moment was frozen for me.  With a beating heart I felt like I had unknowingly been dropped in as an extra in David Attenborough’s Blue Planet.

Click here to see a great film from Dive Instructor Woody captured at Sail Rock in the past few weeks.

So how much do we really know about these creatures that we are jumping in to to see?

The Bull Shark is a Near Threatened (NT) species on the IUCN Red List of Threatened Species  http://marinebio.org/species.asp?id=83 – not currently endangered but close to being. This is largely due to the demand for their fins for gourmet cuisine, particularly in SE Asia. Unlike other sharks the Bull Shark can exist in both salt and freshwater due to it’s unique kidney filtration system. This explains why Bull Sharks can be seen in the Gulf Of Thailand and thousands of miles up the Amazon river. Similar to other sharks the Bull Shark is equipped with a heightened sense of smell and also electroreception sense. The shark has a system of jelly-filled pores around the head and mouth called ‘Ampullae of Lorenzini’ that can detect small electric fields of less than 0.01 microvolt. This enhances their predator abilities by being able to sense struggling fish in the water who emit an infrasonic sound known as a “yummy hum”.

Reported to have the most testosterone of any living mammal with the female generally outgrowing the male they are:

Solitary hunters, bull sharks feed on bony fishes, other sharks such as young sandbar sharks, rays, mantis shrimps, crabs, squid, sea snails, sea urchins, mammalian carrion, sea turtles, and, occasionally, garbage.’

 So how do humans and Bull Sharks interact?

Bull Sharks are listed as one of the three species most likely to attack humans alongside tiger sharks and white sharks. People have been killed by Bull Sharks but mostly swimmers and surfers on the surface who appear like fish or seals to the sharks or spear fishers with their catch as they make their ascent to the surface  Other incidents involving Bull Sharks have been due to questionable and highly controversial diving practices such as  those in the Bahamas where dive trips feed the sharks either through chumming or other methods. The dive resort believes that by showing their divers that sharks are not dangerous that they are raising awareness of the plight to save sharks. Experts are divided in their reaction to this attitude with some agreeing and others  strongly disagreeing as they believe that interference in the natural behaviours can only be harmful to sharks and humans.

You Tube provides a veritable treasure trove of content on the search for Bull Sharks with some scary and utterly insane documented dives. One school in Mexico specialises in feeding Bull Sharks by hand. The divers kneel, inches away from the shark, as the Dive master, dressed in chain mail feeds the surrounding sharks fish heads. In Santa Lucia Cuba, divers report witnessing a ‘great show’ as their Divemaster entertains them on the ‘stage’ by feeding the Bull Sharks. Highly dangerous, there have been incidents where the ‘show’ did not go so smoothly .

Apart from the danger the main issue here is in relation to feeding the sharks. The practice upsets the ecosystem, interferes with the shark’s natural behaviours and ultimately is not sustainable for the marine life. It can also be harmful to divers who encounter sharks in the water but are not there to feed them as part of an ‘underwater circus’.  An seasoned Diving Instructor writes about her experience of finding herself in a feeding frenzy of Bull Sharks who were used to being fed by divers. Although shark feeding has not been scientifically proven to bring about shark attacks many experts believe that it greatly encourages unnatural behaviours in the sharks. There has been much controversy in the Red Sea around shark attacks where researchers concluded that feeding sharks led to unprovoked fatal attacks on divers and swimmers. Ralph S. Collier, president of the Shark Research Committee stated:

“So we’re looking at a shark habituated to human beings for getting food, and humans had taught the shark where the food was. And this occurred frequently in the Red Sea. With overfishing in the area, sharks have to come up to the reef area to feed, and now associate food with the human form. It’s very much like training your family dog. When it sees your hand, it sits up to get a bite of that treat.”

Is it dangerous to get in the water with Bull Sharks?

If you’re suffering from Galeophobia (fear of sharks) then yes it is very dangerous for you to get in the water! Thankfully there is no practice of feeding sharks at Sail Rock but unfortunately there are still some boats who are continuing to fish close to the rock when there are divers under the water. Fishing and diving are not mutually compatible sports so hopefully this will stop before it leads to injury. Following safety guidelines when diving should always be the number one priority and there should be no exception when there are sharks in the water. At Haad Yao Divers, one of the oldest dive schools on the Island we believe it is important to provide our guests with the full picture. All of our instructors have previously dived with sharks in other parts of the world and offer clear safety briefings to all of our guests before descent. It is imperative that divers follow these guidelines but also understand that sharks are wild animals and we are in their habitat. Core Sea,  a Conservation Research NGO based on Koh Phangan shared some facts about Bull Sharks and also highlighted how they can be unpredictable even for experts.

Why are sharks important?

Sharks have been swimming in our seas for over 450million years (unlike humans who have only been on the planet for approx. 200,000 years) and are an integral part of the ocean’s ecosystem. Their declining numbers is a series threat for all marine life. Bull Sharks as a Near Threatened species should be respected and not interfered with and most of all not exploited like ‘performing underwater monkeys’. Much valuable work is being carried out across the world to assist shark conservation including – satellite tagging and tracking  but it is a small counter measure to the daily slaughter of ‘finning’  that occurs to serve the tables of mostly wealthy Chinese.

As divers we have the privilege to explore a life other than our own – marine life. It operates by a different set of rules than human life and we have to respect that if we want to protect it so that we can continue to enjoy it. That means that we need to understand that what we meet underwater can be a danger to us and we need to exercise caution and protect ourselves but also can provide us with some of the most beautiful experiences that we might ever have.

In the words of one of the world’s foremost naturalists:

‘It seems to me that the natural world is the greatest source of excitement; the greatest source of visual beauty; the greatest source of intellectual interest. It is the greatest source of so much in life that makes life worth living.’

Let’s try to keep it that way! Remember safety first – you can swim with the sharks but DON’T FEED THE FISH!

Click here to find out more about Haad Yao Divers trips to Sail Rock or contact us for more information.

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Thanks to

Woody for his great film

Core Sea

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