siddharthx
20171125-0I7A3275
The saltwater crocodile (Crocodylus porosus), also known as the estuarine crocodile, Indo-Pacific crocodile, marine crocodile, sea crocodile or informally as saltie, is the largest of all living reptiles, as well as the largest riparian predator in the world. Males of this species can reach sizes up to 6.30 m (20.7 ft) and possibly up to 7.0 m (23.0 ft) in length. However, an adult male saltwater crocodile rarely reaches or exceeds a size of 6 m (19.7 ft) weighing 1,000 to 1,200 kg (2,200–2,600 lb). Females are much smaller and often do not surpass 3 m (9.8 ft).
As its name implies, this species of crocodile can live in marine environments, but usually resides in saline and brackish mangrove swamps, estuaries, deltas, lagoons, and lower stretches of rivers. They have the broadest distribution of any modern crocodile, ranging from the eastern coast of India throughout most of Southeast Asia and northern Australia.
The saltwater crocodile is a large and opportunistic hypercarnivorous apex predator. Most prey are ambushed and then drowned or swallowed whole. It is capable of prevailing over almost any animal that enters its territory, including other apex predators such as sharks, varieties of freshwater and marine fish including pelagic species, invertebrates such as crustaceans, various reptiles, birds and mammals, including humans. Due to their size, aggression and distribution, saltwater crocodiles are regarded as the most dangerous extant crocodilian to humans, alongside the Nile crocodile.
Incomplete fossil records make it difficult to accurately trace the emergence of the species. The genome was fully sequenced in 2007. The earliest fossil evidence of the species dates to around 4.0–4.5 million years ago and no subspecies are known. Scientists estimate that C. porosus is an ancient species that could have diverged from 12 to 6 million years ago. Genetic research has unsurprisingly indicated that the saltwater crocodile is related relatively closely to other living species of Asian crocodile, although some ambiguity exists over what assemblage it could be considered part of based on variable genetic results. Other relatively broad-snouted species such as mugger (C. palustris) and Siamese crocodiles (C. siamensis) seem to be the most likely candidates to bear the closest relation among living species.
The saltwater crocodile has a wide snout compared to most crocodiles. However, it has a longer muzzle than the mugger crocodile; its length is twice its width at the base. The saltwater crocodile has fewer armour plates on its neck than other crocodilians. On this species, a pair of ridges runs from the eyes along the centre of the snout. The scales are oval in shape and the scutes are either small compared to other species or commonly are entirely absent. In addition, an obvious gap is also present between the cervical and dorsal shields, and small, triangular scutes are present between the posterior edges of the large, transversely arranged scutes in the dorsal shield. The relative lack of scutes is considered an asset useful to distinguish saltwater crocodiles in captivity or in illicit leather trading, as well as in the few areas in the field where sub-adult or younger saltwater crocodiles may need to be distinguished from other crocodiles.
The species is considered of minimal concern for extinction. Currently, the species is listed in CITES as follows:
Appendix I (prohibiting all commercial trade in the species or its byproducts): All wild populations except for those of Australia, Indonesia and Papua New Guinea;
Appendix II (commercial trade allowed with export permit; import permits may or may not be required depending on the laws of the importing country): Australia, Indonesia and Papua New Guinea wild populations, plus all worldwide populations bred in captivity for commercial purposes.
The saltwater crocodile was often hunted for its meat and eggs, and its skin is the most commercially valuable of any crocodilian. Unregulated hunting during the 20th century caused a dramatic decline in the species throughout its range, with the population in northern Australia reduced by 95% by 1971. The years from 1940 to 1970 were the peak of unregulated hunting and may have regionally caused irreparable damage to saltwater crocodile populations. The species currently has full legal protection in all Australian states and territories where it is found – Western Australia (since 1970), Northern Territory (since 1971) and Queensland (since 1974). Illegal hunting still persists in some areas, with protection in some countries being grossly ineffective, and trade is often difficult to monitor and control over such a vast range. However, many areas have not recovered; some population surveys have shown that although young crocodiles are present, fewer than 10% of specimens spotted are in adult size range and include no particularly large males, such as Sri Lanka or the Republic of Palau. This is indicative of both potential continued persecution and exploitation and a non-recovered breeding population. In a more balanced population, such as those from Bhitarkanika National Park or Sabah, Malaysia, 28% and 24.2% of specimens observed were in the adult size range of more than 3 m (9 ft 10 in).
Habitat loss continues to be a major problem for the species. In northern Australia, much of the nesting habitat of the saltwater crocodile is susceptible to trampling by feral water buffalo, although buffalo eradication programs have now reduced this problem considerably. Even where large areas of suitable habitat remain, subtle habitat alterations can be a problem, such as in the Andaman Islands, where freshwater areas, used for nesting, are being increasingly converted to human agriculture. After the commercial value of crocodile skins waned, perhaps the greatest immediate challenge to implementing conservation efforts has been the occasional danger the species can pose to humans, and the resulting negative view of the crocodile.
20171125-0I7A3275
The saltwater crocodile (Crocodylus porosus), also known as the estuarine crocodile, Indo-Pacific crocodile, marine crocodile, sea crocodile or informally as saltie, is the largest of all living reptiles, as well as the largest riparian predator in the world. Males of this species can reach sizes up to 6.30 m (20.7 ft) and possibly up to 7.0 m (23.0 ft) in length. However, an adult male saltwater crocodile rarely reaches or exceeds a size of 6 m (19.7 ft) weighing 1,000 to 1,200 kg (2,200–2,600 lb). Females are much smaller and often do not surpass 3 m (9.8 ft).
As its name implies, this species of crocodile can live in marine environments, but usually resides in saline and brackish mangrove swamps, estuaries, deltas, lagoons, and lower stretches of rivers. They have the broadest distribution of any modern crocodile, ranging from the eastern coast of India throughout most of Southeast Asia and northern Australia.
The saltwater crocodile is a large and opportunistic hypercarnivorous apex predator. Most prey are ambushed and then drowned or swallowed whole. It is capable of prevailing over almost any animal that enters its territory, including other apex predators such as sharks, varieties of freshwater and marine fish including pelagic species, invertebrates such as crustaceans, various reptiles, birds and mammals, including humans. Due to their size, aggression and distribution, saltwater crocodiles are regarded as the most dangerous extant crocodilian to humans, alongside the Nile crocodile.
Incomplete fossil records make it difficult to accurately trace the emergence of the species. The genome was fully sequenced in 2007. The earliest fossil evidence of the species dates to around 4.0–4.5 million years ago and no subspecies are known. Scientists estimate that C. porosus is an ancient species that could have diverged from 12 to 6 million years ago. Genetic research has unsurprisingly indicated that the saltwater crocodile is related relatively closely to other living species of Asian crocodile, although some ambiguity exists over what assemblage it could be considered part of based on variable genetic results. Other relatively broad-snouted species such as mugger (C. palustris) and Siamese crocodiles (C. siamensis) seem to be the most likely candidates to bear the closest relation among living species.
The saltwater crocodile has a wide snout compared to most crocodiles. However, it has a longer muzzle than the mugger crocodile; its length is twice its width at the base. The saltwater crocodile has fewer armour plates on its neck than other crocodilians. On this species, a pair of ridges runs from the eyes along the centre of the snout. The scales are oval in shape and the scutes are either small compared to other species or commonly are entirely absent. In addition, an obvious gap is also present between the cervical and dorsal shields, and small, triangular scutes are present between the posterior edges of the large, transversely arranged scutes in the dorsal shield. The relative lack of scutes is considered an asset useful to distinguish saltwater crocodiles in captivity or in illicit leather trading, as well as in the few areas in the field where sub-adult or younger saltwater crocodiles may need to be distinguished from other crocodiles.
The species is considered of minimal concern for extinction. Currently, the species is listed in CITES as follows:
Appendix I (prohibiting all commercial trade in the species or its byproducts): All wild populations except for those of Australia, Indonesia and Papua New Guinea;
Appendix II (commercial trade allowed with export permit; import permits may or may not be required depending on the laws of the importing country): Australia, Indonesia and Papua New Guinea wild populations, plus all worldwide populations bred in captivity for commercial purposes.
The saltwater crocodile was often hunted for its meat and eggs, and its skin is the most commercially valuable of any crocodilian. Unregulated hunting during the 20th century caused a dramatic decline in the species throughout its range, with the population in northern Australia reduced by 95% by 1971. The years from 1940 to 1970 were the peak of unregulated hunting and may have regionally caused irreparable damage to saltwater crocodile populations. The species currently has full legal protection in all Australian states and territories where it is found – Western Australia (since 1970), Northern Territory (since 1971) and Queensland (since 1974). Illegal hunting still persists in some areas, with protection in some countries being grossly ineffective, and trade is often difficult to monitor and control over such a vast range. However, many areas have not recovered; some population surveys have shown that although young crocodiles are present, fewer than 10% of specimens spotted are in adult size range and include no particularly large males, such as Sri Lanka or the Republic of Palau. This is indicative of both potential continued persecution and exploitation and a non-recovered breeding population. In a more balanced population, such as those from Bhitarkanika National Park or Sabah, Malaysia, 28% and 24.2% of specimens observed were in the adult size range of more than 3 m (9 ft 10 in).
Habitat loss continues to be a major problem for the species. In northern Australia, much of the nesting habitat of the saltwater crocodile is susceptible to trampling by feral water buffalo, although buffalo eradication programs have now reduced this problem considerably. Even where large areas of suitable habitat remain, subtle habitat alterations can be a problem, such as in the Andaman Islands, where freshwater areas, used for nesting, are being increasingly converted to human agriculture. After the commercial value of crocodile skins waned, perhaps the greatest immediate challenge to implementing conservation efforts has been the occasional danger the species can pose to humans, and the resulting negative view of the crocodile.