|
| 질의: Wild boar | 결과: 212번째/213 | |
Saltwater Crocodile (Crocodylus porosus) - Wiki
| 제목: | Saltwater Crocodile (Crocodylus porosus) - Wiki
| |
| 해상도: 2560x1920
파일크기: 703115 Bytes
촬영일: 2004:01:14 09:55:02
등록시간: 2007:08:31 21:55:14
|
Saltwater Crocodile
From Wikipedia, the free encyclopedia
[Photo] Saltwater Crocodile (Crocodylus porosus). Source http://library.byways.org/view_details.html?MEDIA_OBJECT_ID=53733 Date January 2004. Author Obtained from Molly Ebersold of the St. Augustine Alligator Farm
The Saltwater or Estuarine Crocodile (Crocodylus porosus) is the largest of all living reptiles. It is found in suitable habitat throughout Southeast Asia and northern Australia. Saltwater crocodiles are known in the Northern Territory of Australia as 'salties'. The Alligator Rivers are misnamed after the resemblance of the 'saltie' to alligators as compared to freshwater crocodiles, which also inhabit the Northern Territory.
Anatomy and Morphology
A healthy adult male saltwater crocodile is typically 4.8 to 7 metres (15.75 to 21.6 ft) long, and weighs up to 770 kg (1697 lb), with many exceptions claimed as much larger than this. Females are much smaller than males, with typical female body lengths in the range of 2.5???3 meters. A 28 foot (8.5 meters) individual was reportedly shot on the Norman River of Queensland in 1957 and a cast was made of this animal (which can be viewed and is quite the popular tourist attraction), but due to the time since the occurrence and lack of rock hard evidence (other than the plaster) it is not considered "official". The saltwater crocodile has fewer armor plates on its neck than other crocodilians, and its broad body contrasts with most other lean crocodiles, leading to early unverified assumptions the reptile was an alligator.
Distribution
Saltwater crocodiles are severely depleted in numbers throughout the vast majority of their range, with sightings in areas such as Thailand, Cambodia, Laos and Vietnam becoming extremely rare and the species may in fact even be extinct in one or more of these countries. With that said, it is also the least likely of crocodilians to become globally extinct due to its wide distribution and almost pre-colonial population sizes in Northern Australia and New Guinea. In India this crocodile is extremely rare in most areas but is very common in the north eastern part of the country (mainly Orissa and the Sunderbans). The population is sporadic in Indonesia and Malaysia with some areas harboring large populations (Borneo for example) and others with very small, "at risk" populations (the Philippines). The saltwater crocodile is also present in very limited portions of the South Pacific, with an average population in the Solomon Islands, a very small & soon to be extinct population in Vanuatu (where the population officially only stands at three) and a decent but at-risk population in Palau (possibly rebounding).
Saltwater crocodiles have earlier prevailed as far west as the east coast of Africa at the Seychelles Islands, and all the way up the coast of Africa . These crocodiles were once believed to be a population of Nile crocodiles, but they were later proven to be Crocodylus porosus.
Habitat
Saltwater crocodiles generally spend the tropical wet season in freshwater swamps and rivers, moving downstream to estuaries in the dry season, and sometimes traveling far out to sea. Crocodiles compete fiercely with each other for territory, with dominant males in particular occupying the most eligible stretches of freshwater creeks and streams. Junior crocodiles are thus forced into the more marginal river systems and sometimes into the ocean. This explains the large distribution of the animal (ranging from the east coast of India to northern Australia) as well as it being found in odd places on occasion (such as the Sea of Japan, for instance). Saltwater crocodile speed underwater can be 15 to 18 miles per hour in short bursts, but when cruising can go 2 to 3 miles.
Behaviour
The saltwater crocodile is an opportunistic predator capable of taking animals up to the size of an adult male water buffalo, either in the water or on dry land. Juveniles are restricted to smaller items such as insects, amphibians, crustaceans, small reptiles and fish. The larger the animal grows, the greater the variety of items that it includes in the diet, although relatively small prey still make up the majority of the diet even in adults. Saltwater crocodiles can take monkeys, kangaroo, wild boar, dingos, goannas, birds, domestic livestock, pets, water buffalo, shark, and humans, among other large animals as well. Generally very lethargic ??? a trait which helps it survive months at a time without food ??? it typically loiters in the water or basks in the sun through much of the day, usually preferring to hunt at night. Whilst capable of explosive bursts of speed when launching an attack from the water, crocodiles are incapable of sustaining that speed on land. The reported stories of crocodiles being faster than a race horse for short distances across the ground are little more than urban legend.
As an ambush predator, it usually waits for its prey to get close to the water's edge before striking without warning and using its great strength to drag the animal back into the water. Most prey animals are killed by the huge jaw pressure of the crocodile, although some animals may be incidentally drowned. It is an immensely powerful animal, having the strength to drag a fully grown water buffalo into a river, or crush a full-grown bovid's skull between its jaws.
In its most deadly attack, called the "Death Roll," it grabs onto the animal and rolls powerfully. This is designed to initially throw any struggling large animal off balance making it easier to drag it into the water. The "Death Roll" is also utilized as a method for tearing apart large animals once they are dead.
The salt water crocodile, while not known for stalking humans, is one of the major animals involved in attacks on humans in Southeast Asia and Australia. In addition, it has been responsible for the deaths of 12 people between 1975 and 1988 in Northern Australia alone.
Intelligence
Dr. Adam Britton, a researcher with Big Gecko, has been studying crocodilian intelligence. In so doing, he has composed a collection of Australian saltwater crocodile calls, and associated them with behaviors. His position is that, while crocodilian brains are much smaller than that of mammals (as low as 0.05% in the saltwater crocodile), they are capable of learning hard tasks with very little conditioning. He also infers that the crocodile calls hint at a deeper language ability than currently accepted. He suggests that saltwater crocodiles are smart, clever animals that can possibly learn faster than lab rats.
http://en.wikipedia.org/wiki/Saltwater_Crocodile
| The text in this page is based on the copyrighted Wikipedia article shown in above URL. It is used under the GNU Free Documentation License. You may redistribute it, verbatim or modified, providing that you comply with the terms of the GFDL. |
|
댓글 |
|---|
| | 손님 |
|
Scientific Name: Crocodylus porosus Schneider, 1801
Common Names:
English – Salt-water Crocodile, Estuarine Crocodile, Saltwater Crocodile, Indo-Pacific Crocodile
French – Crocodile d'estuaire, Crocodile marin
Spanish – Cocodrilo Poroso |
^o^
동물그림창고 똑똑전화 누리집
^o^
|
|
|
