Crocodiles have been around in Sri Lanka for thousands of years. With many rivers and over 1,200 km of coastline, there has always been a large population of these animals in Sri Lanka. However, of late, there have been many sightings of crocodiles in and around suburban and urban areas of the country.
This could certainly be due to more easy photography and publicity via social media, with many people now having access to smartphones. However, there is also the possibility that the original habitats of these animals are getting disrupted due to human activity, resulting in them migrating to more human populated areas.
Crocodile species and characteristics
Crocodiles (family Crocodylia) are large semi-aquatic reptiles that live throughout the tropics in Africa, Asia, the Americas, and Australia. There are three species: alligators (Alligatoridae), crocodiles (Crocodylidae), and gharials (Gavialidae), according to the journal Pathology of Wildlife and Zoo Animals.
The most obvious external differences between a crocodile and an alligator is the shape of the head, with crocodiles having narrower and longer heads with a more V-shaped snout compared to alligators and caimans that have a more U-shaped snout. The gharial on the other hand, is quite easily identified with its long snout with a protrusion at the end.
Crocodiles are carnivorous reptiles and are generally at the top of the predator list in their ecosystems. The jaws of a crocodile can bite down with immense force, by far the strongest bite of any animal. The force of a large crocodile’s bite is more than 3,700 pounds per square inch (psi), or 16,460 newtons of bite force. By contrast, a human would bite on a steak with 150-200 psi (890 newtons). Hyenas, lions, and tigers generate around 1,000 psi (4,450 newtons).
Despite the massive strength of their jaws in biting down, crocodiles have extremely small and weak muscles to open the jaw. This is the reason one sees crocodiles subdued for study or transport by taping their jaws or holding their jaws shut with large rubber bands cut from automobile inner tubes on TV (for instance, the late Steve Erwin).
Crocodiles have a good sense of smell, enabling them to smell prey from a long distance off. They have very good night vision and are usually night hunters. They can reach speeds of 10-11 km/h (6-7 mph) when they ‘belly run’ and often faster if slipping down muddy riverbanks.
Most interestingly, crocodiles have been around for about 85 million years, but their earliest ancestors evolved around 200 million years ago during the Late Triassic and Early Jurassic. Over these periods, crocodiles have not changed much and are said to be one of the planet’s greatest survivors of evolution (along with the lowly cockroach).
Crocodiles in Sri Lanka
During the Portuguese occupation of Sri Lanka, the Colombo Fort main entrance was located at the foot of the Wolvendaal Hill in the Pettah area. The entrance was called Kayman’s Gate (‘Kaiman Dorakada’) and a historic free-standing bell tower still stands at the site, now at the intersection of Main and 4th Cross Streets.
Interestingly, Kayman’s Gate comes from the Dutch word ‘kaaiman,’ meaning crocodile. During that period, mugger crocodiles were found in large numbers in the Beira Lake and would congregate in the moat to eat rubbish thrown out by the city dwellers within the fort. The south-north canal linking Beira Lake to the sea was used by crocodiles to migrate downstream towards the more brackish water near the sea.
It is evident crocodiles have been sighted and recorded as early as the 17th century in Sri Lanka, but have definitely been around for much longer.
Sri Lanka is home to two crocodile species, the saltwater or estuarine crocodile (Crocodylus porosus) called ‘hela kimbula’ in Sinhalese and ‘semmookan’ in Tamil and the mugger or marsh crocodile (Crocodylus palustris) called ‘geta kimbula’ in Sinhala and ‘chaanakan’ in Tamil.
- Saltwater crocodile
The largest living reptile and most aggressive of all crocodiles. It is a big-headed species and has a relatively broad snout, especially when older. The colouration is pale yellow with black stripes when young but dark greenish drab coloured as adults. Lives in brackish and marine or coastal environments as well as lower stretches of rivers with mangroves, marshes, and swamps. It is the apex predator throughout its range and preys on virtually any animal within its reach. It has a wider distribution in Sri Lanka than the marsh species.
Unlike mugger crocodiles, saltwater crocodiles are highly territorial and won’t tolerate the introduction of a new individual into their range, leading to fights that often end up in one of the animals being killed.
- Mugger crocodile
Somewhat smaller in size, the marsh or mugger crocodile has a very broad snout and is dark grey to brown in colour. It prefers slow moving rivers, swamps, and lakes. The marsh species is mainly restricted to the lowland dry zone of the island, in tanks, streams, rivers, and other suitable inland water bodies. The Yala National Park is supposed to have one of the densest populations of mugger crocodiles in the world. Even though earlier the two species shared habitats in many locations, they now coexist in only a few places.
Crocodiles and the environment
Environmentalists understand that crocodiles play an important part in the ecosystem of a wetland and its related biodiversity. As adults, they regulate the populations of other animals by consuming them and stopping them from overcrowding and degrading ecosystems. Crocodiles also create habitats for other animals by burrowing and nest building.
In 2012, the authorities translocated a 4.2 m (13.8 ft), crocodile from Nilwala River to the Yala National Park. Over time, it made its way over a 120 km journey back home to the Nilwala River. There are other records available of such translocations where the animal has found its way back to its home range. This indicates that crocodiles are territorial.
Hence, there has to be a trade off between environmental protection and safety of humans. Records of a study done indicate that from 2008-2012 there were only 33 crocodile attacks on humans (most of them by saltwater crocodiles), of which only eight were fatal [1]. In comparison, in 2009 alone there were 2,641 fatal road accidents [2].
An example of a ‘kimbul kotuwa’ built for villagers’ protection
Unusual crocodile sightings
- Matara
A huge 17 foot (5.18 m) long saltwater crocodile that had got stuck in a canal along the Nilwala River in Matara was captured in 2016 and released by villagers. It is perhaps the largest crocodile on record on the island. There is a video of the capture and release by the BBC.
- The resident crocodile at Vil Uyana Hotel, Sigiriya
The iconic Vil Uyana Hotel in Sigiriya is home to a large female mugger crocodile, whom I have named ‘Villy’. She must be about 10 ft (about 3 m) long. How and when she arrived at the hotel is rather vague, but Sunela Jayawardene, the architect of the hotel, recalls sighting her during the construction as a very young juvenile. This indicates that she has been around the hotel since its inception and made it her home. She wanders around the far side of the water body and sometimes even basks along the gravel roads. She has so far never been a threat to anyone, but has proved to be quite an attraction to the visitors of the hotel.
In 2021 she gave birth to about 16 hatchlings. It is uncertain where they are now, because as they grew up they would have migrated to other locations [3].
- Crocs in the city
Colombo is one of the world’s most densely populated cities with many wetlands and it has been accredited as an international RAMSAR wetland site in 2018. It is also an accredited wetland capital city in the world [4].
The network of canals that were developed by the Dutch for transportation serves as migration routes for a reasonable population of saltwater crocodiles. Today, these canals are believed to be home to about over 30 medium to large crocodiles, according to leading herpetologist Mendis Wickramasinghe.
Another veteran herpetologist and IUCN Crocodile Specialist Group Regional Chairman Anslem de Silva told Mongabay that the crocodiles in the Colombo canal system used a sea-based route to migrate through the south-western Panadura Canal and into Lake Bolgoda, about 16 km (10 miles) south of Dehiwala. He also said that saltwater crocodiles could survive in the sea and were known for their ability to swim long distances in the ocean, so it was no surprise to find them in the sea around Colombo.
There have been many sightings of ‘salties’ in the heart of Colombo.
On 3 January 2022, a man collecting ornamental marine fish was dragged away by a large saltwater crocodile while diving off Dehiwala. Rather coincidentally, just a week after the incident, a crocodile was seen on the Galle Face promenade, a popular beach for the locals. This is right opposite the Shangri-La and Taj Hotels.
On 28 September 2022, a headless corpse of a man was sighted on the southern beach of Akuressa. Attempts to locate the body proved unsuccessful and it was concluded that it was a crocodile attack.
There have been regular sightings along the coast, especially at river mouths. It is also reported that there are crocodiles along the many waterways of Colombo City, where outdoor walking paths are constructed. There are crocodiles in the Diyawanna Oya near Parliament, the Attidiya Wetlands, and even at the Nawala Weli Park.
There have been calls from the public for the Department of Wildlife Conservation (DWC) to set up traps to catch crocodiles and translocate them, but this is not the answer, as seen from earlier experiences of translocation. The answer is coexistence.
At Weli Park, Nawala, a wire fence has been erected along the sides of the walkways ensuring that the three resident crocodiles stay in the waterways. Since then, sightings on the walking path have diminished. In addition, warning signs have also been erected.
Crocodiles or humans?
While sighting a crocodile in the heart of the city is exciting, it can also be frightening. With pictures now being shared widely via media, some of these interactions can reinforce public fear and intolerance of wild animals. To many, crocodiles are ‘loathsome, ugly, and dangerous’ animals. As seen earlier, nothing could be further from the truth about this great survivor over the ages. Crocodiles would like to avoid human interaction as far as possible. Real attacks are few and far between.
While conflict is an inevitable part of life, it is also the element of these relationships that gets the most attention. It is easier to count negative incidents than highlight scenarios where these things don’t happen.
With careful management, coexistence can be achieved as demonstrated by some of the above examples. Proper education about crocodile behaviour should be provided to the public.
Crocodile exclusion pens (‘kimbul kotuwa’) have proved to be successful in inland reservoirs where villagers bathe.
After all, this small island boasts of the largest animal that ever lived on earth – the blue whale, the largest terrestrial animal – the elephant, and the smallest living animal – the pygmy shrew. So why can’t we also accommodate one the world’s oldest animals?
(The writer is a passionate wildlife enthusiast and advocate who has a close attachment to elephants in particular. He lives in the city with one dog and two cats, but would be far happier in the jungle with the wild animals)