back to BigPinkShark homepage

View Bull Shark Blog

Click on the photos below to enlarge

Grey Reef Sharks at Chumphon Pinnacle are a Load of Bull!

‘Thousands of people have been diving with young bull sharks at Chumphon Pinnacle, thinking they were grey reef sharks’
claim Robin Nagy and Richard Campbell.

Bull Shark - Click to Enlarge
Bull Shark at Chumphon Pinnacle (2007)

‘Two top shark experts independently confirm that these are not grey reef sharks.’
says Robin Nagy.

 

Chumphon pinnacle is one of the most popular and perhaps the most spectacular dive locations in the Gulf of Thailand. Its excellent diving conditions attract thousands of divers each year, drawn to this spectacular site with a chance of seeing a shark or two.

If you ask any dive professional on Koh Tao (the island closest to Chumphon) they will tell you that the shark you are most likely to see on this sea mount (apart from the elusive whale shark) is a grey reef shark. Occasionally, someone claims to have seen a bull shark (or ‘zambizi shark’) on the pinnacle (including Robin and myself) only to be told firmly by those who ‘know’ that ‘…there are only grey reef sharks at Chumphon but they are big!’.

 

Koh Tao - Click to Enlarge
Koh Tao
Chumphon Pinnacle - Click to Enlarge
Divers on Chumphon Pinnacle
Robin and I have dived Chumphon many times with diving organisations on Koh Tao in the hope of seeing sharks. Sharks are our ‘thing’ and we have dived all over the world specifically looking for these magnificent animals. The difficulty in seeing sharks at Chumphon with the big dive operations, is that there can be hundreds of people in the water, circling the site, getting lost, banging tanks and creating so many bubbles that the site sometimes resembles a Jacuzzi. Sharks are very timid and are easily scared off. Diving on Chumphon from the big diving boats, on the occasions that we did see sharks, it was usually fleetingly, in the distance or in silhouette. But each time there was something not quite right, the shape of the sharks was not like any grey reef shark we had seen, they were simply too big, the wrong shape and the wrong colouration.

From the size and shape of our sightings over the years, Robin and I suggested that there may be one or more bull sharks at Chumphon. Our dive friends and colleagues remained unconvinced and we even found ourselves having our legs pulled a bit for considering the idea, ‘…they are all grey reef’s - definitely no bulls’. The consensus of opinion is that the sharks at Chumphon are too small for bulls and behave in a skittish manner, like grey reefs. Most shark sightings at Chumphon are reported as grey reef sharks. We looked at many internet images of sharks at Chumphon all claiming to be grey reef sharks but guess what? – we are now convinced that they are all bull sharks!

 

Bull Shark - Click to Enlarge
Bull Shark on Chumphon Pinnacle (2004)
Bull Shark - Click to Enlarge
Bull Shark on Chumphon Pinnacle (2004)

On looking at the web images and researching the physical characteristics of both species, Robin became more convinced than ever that what he was seeing were the bigger and pelagic bull sharks and not the smaller, skittish grey reef sharks. I became more convinced they were greys, after all, how could so many people be wrong? We decided we needed some more definitive evidence and arranged a charter with ‘DJL divers’ on Koh Tao.

We chose ‘Davy Jones’ Locker’ because Tim Lawrence, the owner of the organisation, knows Chumphon well and has a fast rib which can do Koh Tao to Chumphon in 10-15 minutes. Tim was also happy to dive the site ‘out of sequence’, when the big operators had moved on from their morning dive at the site.

Click to go to DJL Divers' site

Click to go to DJL Divers' site

DJL Divers' Rib
DJL Divers' Rib

In order to get a positive ID, Robin needed to get some good photographs of the sharks from a variety of angles. This necessitated getting very close to the sharks, especially as they are usually found quite deep on Chumphon and often hang around in the murky water below the thermocline. As luck would have it, we bumped into a dive instructor friend of ours, Tod Applegate, the night before our dive who has perfected a technique of ‘calling in’ sharks with a plastic bottle, he was eager to come.

 

 

Bull Shark - Click to Enlarge

Bull Shark on Chumphon Pinnacle (2004)
Richard diving Chumphon - Click to Enlarge
Richard Diving on Chumphon Pinnacle
The next day saw us hurtling towards a beautifully clear Chumphon at up to 30 knots on Tim’s rib complete with Tod (who had chosen a suitable bottle for his ‘calling’). The weather was a bit choppy when we arrived, and Tod lost a shirt over board, a backward roll into the excellent viz and we watched Tod’s shirt descend into the depths with a curious shark sinking effortlessly with it! Then another and another; Tod forgot about his shirt and ‘called’. Another shark came in from behind like a bullet, yet another from above - these weren’t behaving like skittish grey reef’s, I thought. Two sharks in particular, each about 2 meters long became more and more interested in me, taking it in turns to circle in, one from the front, the second from behind, each time getting a little closer.

We counted up to 15 sharks at once, on this first dive and Robin was able to get close up photographs of them. Diving on Nitrox allowed us to spend more time at depth and the sharks were able to get comfortable with our presence. The sharks came very close (around 2 meters) to us displaying an inquisitive rather than an aggressive attitude.

With only three of us in the water at Chumphon, it is likely that the absence of people encouraged the sharks to act naturally – in other words like confident bull sharks and not like skittish grey reef sharks.

 

Richard watching Bull Sharks - Click to Enlarge

Richard Watching Bull Sharks on Chumphon Pinnacle (2007)
Bull Shark - Click to Enlarge
Bull Shark on Chumphon Pinnacle (2007)

On the second dive, at the same location, again the sharks came in close to have a good look at us and again no aggressive behaviour was observed, just curiosity and interest. With the thick set upper body heavy set fins, I became confident we were looking at bull sharks; I made a ‘Z’ sign for Zambezi (the South African name for bulls), Robin agreed. We had dived with some very big zambezis on South Africa’s famous “Protea Banks” and these were like perfect miniatures of the same species.

 

Back in Bangkok, we looked again at the photographs of ‘grey reef’ sharks at Chumphon, posted on the internet. We compared Robin’s photographs of the sharks at Chumphon with his photographs of grey reef sharks taken in the Maldives. They were strikingly different: The grey reef shark (Carcharhinus amblyrhynchos) has relatively larger eyes and a more pointed head than the bull shark (Carcharhinus leucas), with it’s blunt rounded snout (which is why the bull shark is sometimes known as the shovelnose or square-nose shark). The bull shark’s mouth has a more open aspect than the grey reef, neither shark displaying teeth when at rest. The size and shape of the dorsal fins are clearly different, with the bull shark having a first dorsal fin which is much less upright and triangular and much more swept back, broader and shaped more like a breaking ocean wave. The second dorsal fin is relatively bigger in a bull shark when compared to the size of the first. Whilst the body colouration of both types of shark is similar, the grey reef shark has a broad dark band on its caudal (tail) fin and black tips and margins to its other fins. In parts of the world such as the Maldives, the grey reef shark has a white tip on its first dorsal fin. The bull shark has darker areas at the points and edges of its fins, however, these are not nearly as distinct as with the grey reef. These darker areas fade as the bull shark grows and the overall impression is of a much more uniform light grey body colour, although individual sharks may have lighter or darker spots and lines on their bodies. Both species have a white underside. Grey reefs are usually smaller and more streamlined than the stocky, heavy set bull shark.

 

Grey Reef Shark - Click to Enlarge
Grey Reef Shark Photographed in the Maldives (2007)

Bull Shark - Click to Enlarge
Bull Shark Photographed at Chumphon Pinnacle (2007)

Bull Shark - Click to Enlarge
Bull Shark on Chumphon Pinnacle (2007)

The confusion at Chumphon might be that people are muddling sub-adult bull sharks with fully grown grey reef sharks. This is perhaps unsurprising given the fact that both sharks share both the same family (Carcharhinidae) and genus (Carcharhinus) It is now clear to us that all the sharks we have ever seen on Chumphon Pinnacle have been juvenile to small adult bull sharks and definitely not grey reef sharks.

Of course, we had to get independent verification of our observations and contacted two world authorities on shark species, in other words those people who really ‘know’, with a full selection of Robin’s photographs. Mr. Geremy Cliff the head of research at the Natal Sharks Board, South Africa ruled out the grey reef shark straight away. He attached two photographs of grey reef sharks from South Africa and said:

“Notice the different shape of the first dorsal fin and the small second dorsal. [Your photographs] are clearly not grey reef. They certainly look like Zambezi [bull shark] which does occur in Thailand. … I don't think that there is anything else that [your sharks] could be."

Furthermore, on seeing our photographs, another expert, Neil Hammerschlag, of the South Florida Student Shark Program (SFSSP), Rosenstiel School of Marine & Atmospheric Science (RSMAS), University of Miami, was also in no doubt that they were of bull sharks.

 

Perhaps one of the reasons the truth has never come out about the bull sharks of Chumphon is that the name “bull shark” sends shivers down some peoples’ spine and because this species of shark is reputed to be dangerous to man, apparently one of the three species most likely to be involved in a shark attack. However, it is important that we understand the behaviour of these sharks before we start jumping up and down in panic, and to examine the statistics a bit closer.

On investigating bull shark attacks, we found absolutely no evidence around the world of any scuba divers being attacked by sharks unless the diver was behaving in a manner which would actively change the sharks’ behaviour. Scuba diver victims were either spear fishing, baiting or feeding the shark at the time of the attack. To our knowledge, there have been no records of any divers ever being attacked by sharks at Chumphon or for that matter anywhere else in Thailand.

 

Bull Shark - Click to Enlarge
Bull Shark Emerging from the Thermocline
Bull Shark - Click to Enlarge
Bull Shark on Chumphon Pinnacle (2007)

Geremy Cliff had this to say on the subject:

“Shark attacks on scuba divers are very rare, for a number of good reasons. We dive in very clear water, don't thrash around much at the surface like swimmers and surfers do and we dive in large groups, making lots of bubbles to scare off potential aggressors. In South Africa bull sharks are a problem where fish have been speared and in very shallow, often murky water. While the big Zambis on Protea Banks are fearless and do come very close, I am not aware of any attacks.

Despite the fact that there are, most probably, bigger bull sharks in the Gulf of Thailand than you can see at Chumphon, the International Shark Attack File records just one shark attack in Thailand, in the year 2000. The only other reference we could find to a shark attack in Thailand (which may well be the same one) is of a fisherman who didn’t realise he had a shark in his net. We could not find any reference to an attack on a scuba diver in Thai waters.

 

‘Bull sharks on Chumphon Pinnacle’ is fantastic news for the dive industry on Koh Tao. There are very few places on earth where you can easily dive with bull sharks. It is also extremely encouraging to observe so many persecuted animals apparently thriving in Thai waters, which is near the centre of the vile trade in shark fins. All divers and operators on Koh Tao have a responsibility to actively engage in the protection and survival of these magnificent animals.

 

Bull Shark - Click to Enlarge
Bull Sharks Circling on Chumphon Pinnacle (2007)
Bull Shark - Click to Enlarge
Bull Shark Taking a Closer Look at us

Bull sharks have a reputation for being aggressive and unpredictable, but they are not so at Chumphon. Literally thousands of people have dived at Chumphon Pinnacle for many years, without a single ‘shark’ incident. However, we would strongly advise against any activities at Chumphon which would actively change the behaviour of these sharks, including ‘shark calling’, baiting, and spear fishing, chumming or feeding the sharks. These animals should be treated with respect.

 

In ‘calling in’ the sharks to obtain the photographs in this article, Robin and I relied on 30 years of collective experience diving with sharks on 5 different continents. Tod is an experienced diving instructor and well versed in shark behaviour.

Chumphon is perhaps one of the best places in the world to see the magnificent bull shark. It remains as spectacular and safe a place to dive as it has ever been, so please keep diving there and keep an eye out of a load of bull!

Bull Shark - Click to Enlarge
Bull Shark on Chumphon Pinnacle (2007)

Article by Richard Cambell and Robin Nagy © August 2007, first published on BigPinkShark on 12th September 2007
All Photographs ©Robin Nagy 2007
Our thanks to
Neil Hammerschlag and Geremy Cliff for their expert opinions



Number of hits: