Saltwater Crocodile, Crocodylus porosus

Distribution (see below for detailed information)
Australia, Bangladesh, Brunei, Cambodia (Extinct), China (Extinct), India, Indonesia, Malaysia, Myanmar, Palau, Papua New Guinea, Philippines, Seychelles (Extinct), Singapore, Solomon Islands, Sri Lanka, Thailand (Extinct), Timor-Leste, Vanuatu (Extinct?), Vietnam (Extinct)

Red List Status
Least Concern (LC)

Size
4-4.5 meters (male average); 6.2 meters (confirmed maximum); 7 meters (suspected maximum)

Threats
Human-crocodile conflict; habitat fragmentation & loss; human population growth & expansion; retaliatory killings

Notes on Human-Crocodile Conflict
Adult saltwater crocodiles, like Nile crocodiles, frequently attack and kill humans. In recent years an average of 120-130 deaths have been recorded annually, though this number is believed to be higher, due to data deficiency from New Guinea. Extrapolated, it is possible that saltwater crocodiles are responsible for 150-200 human deaths annually, mostly in Indonesia. It is suspected that certain industries (particularly oil palm, tin-mining and aquaculture) have created conditions that have resulted in increased attack frequency, such as habitat destruction and reduced natural prey abundance.

Detailed Distribution

Australia
Tropical northern Australia likely holds the largest remaining populations range-wide. The Top End of the Northern Territory is home to most, with an estimated 100,000 non-hatchlings present. Queensland's population remains vulnerable, with around 30,000. Resident breeding populations are found from Broome in Western Australia through the entire tropical northern coast to Gladstone in Queensland, with wandering individuals occasionally found further south along both coasts. Crocodile attacks, particularly fatalities, are relatively rare in Australia.

Bangladesh
Populations only remain within the Sundarbans of Khulna Division, but was historically present in virtually all coastal habitat, as well as in some inland areas. It is unclear how frequent crocodile attacks are in Bangladesh, since many incidents are believed to go unreported.

Brunei
Present in most suitable habitat, including far inland along some of the major waterways, such as Belait and Tutong rivers. Less than one person has been killed by a crocodile annually in Brunei over the past decade, but there appears to be a local view that crocodile attacks are becoming a problem.

Cambodia
Formerly present in suitable habitat along the southern coast (such as modern-day Peam Krasaop Wildlife Sanctuary, Botum Sakor National Park, and Ream National Park), as well as inland along the Mekong River and Tonle Sap Lake, where the species appears to have been sympatric with the Siamese crocodile (C. siamensis). Extinction likely occurred at some point during the late 20th Century, with the last official record being a 3 meter individual captured in Koh Kong Bay in 1990. Attacks on humans appear to have been a major issue historically, with the saltwater crocodile apparently being feared more than the tiger by Cambodians.

China
Historical records suggest a presence from Fuzhou southward to the border with Vietnam, including the Pearl River delta and Lantau Island, where skeletal remains have been recovered, as well as Hainan Island. Populations appear to have been drastically reduced by the end of the 13th Century due to large-scale human migration southward, but some may have persisted into the 18th or early 19th centuries. Historical literature describes the species as preying upon humans and livestock.

India
Formerly found from at least as far north as the lower Periyar River north of Kochi along the southwestern coast of Kerala through the entirety of the eastern coast to the Bangladeshi border. Today mainland populations are only found in Odisha's Bhitarkanika National Park (which holds what is almost certainly the single largest saltwater crocodile population remaining in all of mainland Asia) and the Sundarbans of West Bengal. The species is also found throughout most of the Andaman and Nicobar Islands. Unfortunately, attacks on humans appear to be a problem in all areas where the species remains.

Indonesia
The species appears to be recovering throughout much of the Indonesian archipelago, though the small amount of surveys that have been conducted (mostly in areas experiencing high levels of attacks on humans) have revealed low densities (often <1 individual per km). Despite this, there appear to be resident saltwater crocodile populations of varying sizes in all provinces except Bali, Central Java, Yogyakarta, Jakarta, and possibly East and West Java (there are reports of crocodiles, but these could be individual wanderers). The largest populations in Indonesia are believed to be found in the sparsely populated western half of New Guinea, though recent survey data is lacking.

Attacks on humans are an issue, with at least 85 people being killed country-wide in 2023 alone. The true number is believed to be higher, due to a lack of reporting from some areas (particularly West Papua). The most serious areas in recent years have been Bangka-Belitung, East Kalimantan, Central and Southeast Sulawesi, and the Malukus. Potential exacerbating factors include industries (tin-mining, oil palm), poverty, and human population growth/expansion.

Malaysia
Like Indonesia, populations in Malaysia also appear to be recovering, possibly to an even more significant extent. Recent surveys in Sarawak have revealed widely varying numbers of crocodiles, likely due to a combination of environmental factors and the inclusion of hatchlings in counts. The crocodile population in the state is currently estimated to consist of 13,000 individuals. Sabah also appears to have a recovering population, particularly along the Kinabatangan River. Also like in Indonesia, attacks on humans are a major issue. Potential exacerbating factors are the same as in Indonesia. Populations also remain in Peninsular Malaysia, some of which may be significant, based on survey data. However, unlike in Sarawak and Sabah, attacks on humans in Peninsular Malaysia are exceptionally rare (only four non-fatal incidents in the past decade), though they were very frequent historically.

Myanmar
Remains only within Meinmahla Kyun Wildlife Sanctuary (which may hold the second largest single population remaining in mainland Asia) and within portions of Tanintharyi Division (such as Kanmaw Island and mainland portions of Bokpyin township). Attacks on humans do occur at both locations, but it is unclear to what degree they go unreported, particularly in Tanintharyi.

Palau
The only resident population with Micronesia. Crocodiles are found in many areas of suitable habitat, though large individuals appear to be rare. The most recent surveys, which were conducting in the 2000s, revealed no crocodiles >3 meters in length. Attacks on humans are also very rare in modern-times, with only one non-fatal bite incident being reported in 2012 and the last fatality occurring in 1965. Crocodile size is unlikely to play a significant role in the low attack frequency, since non-fatal incidents involving crocodiles in the 1.5-2 meter size range are relatively common in other areas, such as Indonesia.

Papua New Guinea
Along with the Indonesian western half of New Guinea, Papua New Guinea is the only area outside of Australia that may hold near pre-exploitation sized saltwater crocodile populations. Though surveys for areas outside of the Sepik River region have not been conducted since the early 1980s, the large amount of habitat and relatively low human population density suggests that significant populations may remain. The species can be found far inland along the major waterways, such as the Fly, Sepik, and Ramu basins. They are also present on most of the islands, including Bougainville, Manus, New Britain, New Ireland, New Hanover, and throughout the Louisiade Archipelago, including Sudest Island. Attacks on humans are a major issue in Gulf Province and are suspected to be frequent elsewhere as well.

Philippines
Formerly present throughout suitable habitat in the entire archipelago, including far inland in some areas, such as along the Cagayan River basin in Luzon. Today viable populations only remain in southern Palawan and the Balabac Islands, Tawi-Tawi, Mindanao (Agusan and Liguasan marshes), the Del Carmen mangroves of Siargao Island, and a very small number of locations along the northeastern coast of Luzon (from Palanan northward to the Blos River mouth). Attacks on humans are an issue in southern Palawan and Tawi-Tawi, though not to the same degree as India, Indonesia, or Malaysia.

Seychelles
The crocodiles present in the Seychelles were previously believed to have been Nile crocodiles (C. niloticus), but are now known to have been saltwater crocodiles. Little is known regarding the distribution of the species on these islands, but it was hunted to extinction by 1819. Location names, most notably Roche Caiman, are a reminder of this long extinct population.

Singapore
Historically the species was widespread throughout most of the island, including rivers such as Kallang, Rochor, Punggol, and Serangoon. Today the only viable population exists in Sungei Buloh Wetland Reserve along the northeastern coast, while there appears to be frequent movement of crocodiles between Singapore and Peninsular Malaysia via the Johor Strait. The last non-fatal attack on a human occurred in 1989 and the last reported fatality occurred along the Ulu Pandan River in 1946.

Solomon Islands
Present throughout most of the Solomon Islands, including Choiseul, Santa Isabel, Malaita, Makira, Guadalcanal, New Goergia, most of the smaller islands of Central and Western provinces, as well as all major islands of Temotu Province in the east (Nendo, Utupua, and Vanikoro). Populations do not appear to be present in Bellona and Rennell to the south, though it is unclear if this was always the case. The population has recovered from near extirpation in 1989 and a 2019 study found that attacks on humans have become an issue, though fatalities appear to be far rarer than in certain parts of Indonesia and Malaysia.

Sri Lanka
While believed to have been found throughout all coastal habitat and even some inland areas historically, today the saltwater crocodile population is largely restricted to the west and southwestern coasts, with scattered populations also found at select locations along the southern coast and eastern coast (e.g., Batticaloa Lagoon). Resident populations are believed to be extinct north of Chilaw on the western coast and north of Trincomalee on the eastern coast, though wandering individuals may be found further north and "problem" saltwater crocodiles have been inappropriately released into some inland mugger crocodile (C. palustris) habitat, including in Bundala, Wilpattu, and Yala national parks. The most well-studied population appears to be in the Nilwala River of Matara District. Attacks on humans are an issue, though most recent attacks have occurred in Batticaloa Lagoon area where it is difficult to discern mugger and saltwater crocodile attacks.

Thailand
Historically the species was found in suitable habitat throughout coastal Thailand and likely some inland areas. Unlike in neighboring Cambodia, a relatively large number of historical localities are known for Thailand. Along the northern Gulf of Thailand populations were known to occur in the lower Chao Phraya River in Bangkok, the Tha Chin River in Samut Sakhon, Klong Damnoen Saduak in Ratchaburi, and the Petchaburi River of Petchaburi. Along the eastern Peninsula of Siam populations were known from Klong Guiburi in Prachuap Khiri Khan, Chumphon and Bang Mut rivers of Chumphon, Phunphin River of Surat Thani, Koh Samui Island, Songkhla Lagoon and Lampan River of Songkhla and Phatthalung, where the species may have been sympatric with the Tomistoma (Tomistoma schlegelii), and the Saiburi River of Pattani.

Along the western coast of the Peninsula, locations included Koh Tarutao Island of Satun (which was the location of the claimed "last wild saltwater crocodile in Thailand" in 1971), Trang River of Trang, and both Phuket Island and neighboring Phang-Nga Bay National Park. Today there is a possibility that very small numbers persist in Pra Pru and the Bang Nara River along the border with Kelantan, Malaysia (where a population is confirmed to present), but these may just be wanderers from that population. A population that was claimed to be present in Ranong along the border with Myanmar in the 2000s was never confirmed. The last report of a fatal attack in Thailand came from the Bang Mut River of Chumphon in 1964 and involved a 4.25 meter crocodile dubbed 'Ai Dang'.

Timor-Leste
Crocodiles appear to be widespread and locally common in certain parts of Timor-Leste. The largest population in Timor-Leste (and likely the largest single population throughout the entire Lesser Sunda Islands) is found in the landlocked Lake Ira Lalaro on the Fuiloro Plateau in Lautem District. Several hundred crocodiles are believed to reside in this lake. Crocodiles are also scattered in freshwater habitat throughout the remainder of the plateau, including around Lospalos town. The southern coast is also believed to hold significant populations, due to an abundance of habitat, including numerous estuaries and a few inland freshwater lakes, but no surveys have been conducted to confirm this. Habitat is far more restricted on the northern coast, but in the author's own experience crocodiles can be easily spotted in many of the coast waterbodies, including very large individuals, though the limited amount of habitat restricts their numbers.

Crocodile attacks are common in Timor-Leste, just as they are in neighboring West Timor and the remainder of the Indonesian Archipelago. Some of the highest numbers of attacks occur in the aforementioned high elevation landlocked areas. Many of the coastal communities in Timor-Leste (as well as in West Timor, Lembata, and other portions of Indonesia) view the crocodile as a totem animal, with certain individuals believed to be the embodiment of ancestral spirits. The species also features prominantly in the Timorese creation myth. For these reasons, killing crocodiles is taboo except under specific circumstances. This has likely allowed the species to persist on Timor Island following near eradication from many of the Lesser Sunda Islands to the west.

Vanuatu
The species is only known to be a resident of a couple of rivers along the eastern coast of Vanua Lava and its current status is unclear. Though populations appear to have been stable historically, including very large individuals, the most recently available information suggested that only two individuals remained and that breeding had ceased, indicating a functionally extinct population on the verge of extirpation. However, given the proximity to the Temotu Province of the Solomon Islands, recolonization could always occur, assuming local residents allow it. In addition, this information is at least a decade old, and the current status (as of 2024) is unknown. Attacks on humans do not appear to have been an issue at any time within the past half century, with only one non-fatal incident being recorded.

Vietnam
Formerly present throughout southern Vietnam and likely present along the central and northern coastline historically. Known historically localities include the entirety of the Mekong Delta, as well as nearby areas including the Rung Sat Swamp (which is now called the Can Gio Biosphere). Wildlife surveys in 1969 to assess the impact of American defoliation on the Rung Sat Swamp yielded the sighting of one "large" crocodile basking on a river bank. And there are several accounts of American soldiers encountering crocodiles during the American-Vietnam War, though no reports of attacks on American troops, though there are anecdotal reports of North Vietnamese troops being attacked. Other known localities include the mangroves of Vung Tau and Ba Ria, the Dong Nai River, Ong Keo River, Kien Giang Bay, U Minh Thuong Nature Reserve (surveys in 2000 concluded that the species may have been eradicated up to 30 years earlier), Un Minh Ha, Phu Quoc Island, and the Con Dao Archipelago.

There are two interesting historical attack records from the coast north of the Mekong region, including one on a beach in Nha Trang of Khanh Hoa in 1930 and another at La Gi in Binh Thuan in 1932. The last reported attacked by a saltwater crocodile in Vietnam occurred in Can Gio/Rung Sat in 1976 and involved a woman being killed by a 4 meter crocodile, which was later captured and killed. There have been no reliable reports of wild saltwater crocodiles in Vietnam since at least the 1980s, though a number of physically pure (non-hybrid) saltwater crocodiles are found in captivity in Can Gio, possibly captured locally decades earlier.