W15 Logo

Sharks of Sri Lanka

In the first part of this article we will answer the basic questions on the minds of those who wish to swim, snorkel and surf in Sri Lanka about the sharks in our waters. There are some who will go to the extent of stating that there are no sharks within 5 km of Sri Lanka. This is not true. There are over 60 shark species in the warm waters surrounding the island. Naturally the next question which would follow is: "are shark attacks common in Sri Lanka?" The answer to that is absolutely not. In the last 200 years there have been only 14 attacks of which only 3 have been fatal and there have not been any fatalities in the last 60 years.1 Therefore do not fret or fear come surf and swim in some of the safest waters in world. There are also places where you can snorkel and dive safely alongside reef sharks like at Pidgeon Island.

The next section will dive into the world of sharks in Sri Lanka.In the minds of the majority the term "shark" strikes fear thanks to the image portrayed by many western movies. This couldn’t be farther from the truth. In fact it is the opposite. The number of sharks killed by humans is monumentally large and has led many shark species to fall on the near threatened or endangered list. Sadly looking at the top killers of sharks by country, Sri Lanka ranks at no. 14 globally3.

This picture depicts the shark catch at the Negombo Fish Market which will soon be finned and harvested.

On a more positive note Sri Lanka has passed many regulations prohibiting the catch of sharks in Sri Lanka such as the majestic whale shark and thresher shark. We will now look at the most famous and commonly seen sharks in Sri Lankan waters.

The Whale Shark (Rhincodon typus)

It is the largest shark and largest fish known to man in the world. This gentle giant is a filter feeder and feeds exclusively on plankton and is not a threat to humans. They are a resource for tourism and enthusiasts commonly dive alongside them. They can reach up to 40 feet in length and 20 tonnes in weight. They are a dark grey with light spots and lines on their dorsalsurface while ventrally they are white/yellow in colour. They have longitudinal ridges along their body and small eyes towards the front of the head.

On a more positive note Sri Lanka has passed many regulations prohibiting the catch of sharks in Sri Lanka such as the majestic whale shark and thresher shark. We will now look at the most famous and commonly seen sharks in Sri Lankan waters.

The Bull Shark (Charcharinusleucas)

This highly aggressive shark is probably responsible for the majority of shark attacks on humans in Sri Lanka. They are unique in being capable of osmoregulation and can adapt to live in freshwater and have been seen far up Sri Lanka’s Manik (Jewel) River. They are stocky and large reaching up to 9 feet and 135 kg. Recently however a large individual was caught off Sri Lankan waters estimated to be 14 feet which could be an exaggeration and was identified as Charcharinusleucas based on circumstantial evidence by Sri Lanka’s foremost expert on sharks and batoids, Rex I. de Silva3.

The White Tip Reef Shark (Triaenodonobesus)

It is a species of reef shark which is long, slender and small in size around 5 feet in length. They are easily differentiated from other reef sharks by the white tips on their dorsal and caudal fins. They do not shy away from humans and can be trained to take food from and interact with divers. They are not known to be a threat to humans unless unduly provoked. They are nocturnal feeders and feed off prey items which hide in rock crevices and amongst corals. They often hunt in packs but are not known to engage in feeding frenzies unlike other shark species.

The Black Tip Reef Shark (Carcharhinusmelanopterus)

The black tip reef shark is a bit more robust, lives in shallower water and is slightly larger than the white tip at just over 5 feet in length and as its name suggests has black fin tips on its dorsal and caudal fins. Pidgeon Island in Sri Lanka is one of the best places to dive and snorkel alongside blacktip sharks. They are easily scared away but are notorious for accidentally biting the legs of people wading through shallow water. Fully submerged divers are very unlikely to be bitten. There are no reported fatal attacks on humans by this shark.

Hammerhead Sharks

The term "Hammerhead shark" is a common name for sharks of the family Sphyrnidae which have lateral projections from their heads which give them a hammer like shape. The four species seen in Sri Lankan waters are the Winghead shark, Scalloped hammerhead, Great hammerhead and Smooth hammerhead. Apart from the Winghead, the other three species are known to be dangerous to humans but there have been no fatal attacks on humans by any of them. The hammers which look similar to the nose wings on race cars are thought to aid in providing lift, improving visual range and providing a broader surface area for the shark's electrosensory reception by the ampullae of Lorenzini.

Silky Shark (Carcharhinusfalciformis)

This oceanic shark is arguably the most common shark species in Sri Lankan waters. They grow to be about 2.5m in length and are dorsally metallic grey whilst ventrally white in colour. These sharks hardly interact with humans due to being deep sea sharks but can be a threat to humans as they are not shy. However there are no known fatal attacks from this species.