Mammals

There are an estimated 90 species of land mammal in Sri Lanka, of which 14 (15%) are thought to be endemic. The most well known mammal is the Sri Lankan elephant (Elephas maximus maximus), a sub-species of the Asian elephant identified by its lighter colouring and smaller ears whose numbers both in the wild (2,000-2,500) and in captivity comprise one of the world's largest populations. Unlike the African Elephant only a tiny percentage of male Sri Lankan elephants grow tusks, though the ones that do are majestic to see. Elephants are endangered creatures and are further suffering from loss of habitat as more undeveloped areas are being cleared for agriculture putting these giants in direct confrontation with humans.

The Sri Lankan leopard (Panthera pardus kotiya) is also a highly endangered mammal, one that is both striking and remarkable to see. The island has a high density of leopards, numbering around 500, though they are being further threatened with habitat destruction. Measuring up to two metres in length, these large cats can be hard to spot though and most frequently sighted in Yala National Park where 200 are believed to reside.

There are three species of monkeys and macaques found in Sri Lanka comprising the grey langur (Semnopithecus entellus) with its long tail and silvery appearance, the endemic toque macaque (Macaca sinica) a smaller and more common species that is reddish-brown in colour and the endemic purple-faced leaf monkey (Trachypithecus vetulus) which is brown in colour and by far the most exciting to spot.

Other mammals include the sloth bear (Melurus ursinus) and many types of deer; spotted deer, sambhur deer and muntjac or barking deer. Buffalo are common as well as smaller mammals such as giant squirrels, wild boar, mongoose, jackal, and some species of hare, porcupine, civet, pangolin, fishing cat, rusty spotted cat and the slender loris.

Reptiles

There are 156 reptiles recorded residing in Sri Lanka of which over half, 87 (56%) are endemic to the island. The largest are the two species of crocodile; the mugger crocodile (Crocodilus palustrus) and the estuarine or saltwater crocodile (Crocodilus porosus) that may be seen in Yala or Bundala national parks. While mugger crocodiles grow to four metres in length and prefer freshwater, the estuarine crocodile thrives in brackish water and can grow as long as seven metres in length. A reptile that is commonly confused as a crocodile is the monitor, specifically the water monitor (Varanus bengalensis) due to its similar appearance and two-metre size.

Many lizards can be seen of which a majority are endemic especially in the montane forests of Horton Plains or the steamy sauna of Sinharaja rainforest while some species continue to be discovered. There are also more than 80 species of snake of which seven are poisonous including the Russell ’s viper. The star tortoise is the only land tortoise to be found in Sri Lanka.

Amphibians

Out of 105 species of amphibian recorded in Sri Lanka, 66 of them (63%) are endemic to the island. Many can be solely found in various regions such as in Horton Plains or Sinharaja Rainforest making their existence incredibly specialised.

Birds

Sri Lanka is certainly a haven for bird watchers since it has the second highest species richness in Asia. The island's position on the globe also makes it a highly important location for winter migrants from Siberia, Scandinavia and Western Europe, many of which are shorebirds, sandpipers, stilts, plovers, terns and kites that descend in their thousands to the coastal areas most notably Bundala National Park.

Out of the 240 resident species found on the island, 26 are endemic and found mostly in the wet zone. They include the Sri Lanka blue magpie, the Sri Lanka hanging parrot, the Sri Lanka spurfowl, brown capped babbler, Sri Lanka junglefowl, Legge's flowerpecker, the Sri Lanka white eye, the dusky blue flycatcher and the red-faced malhoka to name a few. A further 200 or more migratory birds have been recorded as visitors.

Butterflies and moths

Flitting about the whole of the island is estimated to be 243 species of colourful butterflies of which 20 (8%) are endemic to the island. Most of them are found in the lower foothills (up to 910m), while six species are found in higher climes. In March-April, a spectacular seasonal migration occurs. There are innumerable numbers of moths, and while there are no proper records to account for their species aside from a few large and colourful ones such as the Atlas Moth, it is believed that there could be over 5,000.

Freshwater fish

There are 107 species of freshwater fish found in Sri Lanka, of which 38 (36%) are endemic to the island, a relatively high number. They can be found in the numerous rivulets, streams, rivers and reservoirs scatted around the island.

Turtles

Five species of marine turtle frequent Sri Lankan shores to lay their eggs and all are highly endangered due to marine hazards and poaching. They include the green (Chelonia mydas), the loggerhead (Caretta caretta), the hawksbill (Eretmochelys imbricata), the olive ridley (Lepidochels olivacea) and the leatherback turtle (Dermochelys conacea).

Others

An estimated 266 species of land mollusc are resident to Sri Lanka of which a staggering 202 (76%) are recorded as being endemic. Estimates as to the number of spider species range upwards of 400 while ground beetles numbering 243 comprise only 20 (8%) endemics.