| Revision as of 01:19, 3 April 2007 view source74.233.157.153 (talk)No edit summary← Previous edit | Revision as of 01:20, 3 April 2007 view source Ali'i (talk | contribs)Extended confirmed users4,404 editsm I need THE osuNext edit → | ||
| Line 18: | Line 18: | ||
| }} | }} | ||
| An '''alligator''' is a ] in the ] '''''Alligator''''' of the ] ]. The name ''alligator'' is an ] form of the ] ''el lagarto'' ("the lizard"), the name by which early ] explorers and settlers in ] called the alligator. There are two living alligator ]: the ] (''Alligator mississippiensis'') and the ] (''Alligator sinensis''). |
An '''alligator''' is a ] in the ] '''''Alligator''''' of the ] ]. The name ''alligator'' is an ] form of the ] ''el lagarto'' ("the lizard"), the name by which early ] explorers and settlers in ] called the alligator. There are two living alligator ]: the ] (''Alligator mississippiensis'') and the ] (''Alligator sinensis''). | ||
| == Description == | == Description == | ||
Revision as of 01:20, 3 April 2007
For other uses, see Alligator (disambiguation).
| Alligators | |
|---|---|
| |
| An American Alligator in captivity at the Columbus Zoo | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Sauropsida |
| Order: | Crocodilia |
| Family: | Alligatoridae |
| Genus: | Alligator Daudin, 1809 |
| Species | |
An alligator is a crocodilian in the genus Alligator of the family Alligatoridae. The name alligator is an anglicized form of the Spanish el lagarto ("the lizard"), the name by which early Spanish explorers and settlers in Florida called the alligator. There are two living alligator species: the American Alligator (Alligator mississippiensis) and the Chinese Alligator (Alligator sinensis).
Description
Alligators are characterized by a wider snout and eyes more dorsally located than their crocodile cousins. Both living species also tend to be darker in colour, often nearly black but color is very dependent on the water. Algae-laden waters produce greener alligators; alligators from waters with a lot of tannic acid from overhanging trees are often darker (although the Chinese alligator has some light patterning.) Also, in alligators only the upper teeth can be seen with the jaws closed (in contrast to true crocodiles, in which upper and lower teeth can be seen), though many individuals bear jaw deformities which complicate this means of identification.
The eyes of a large alligator will glow red and those of a smaller one will glow green when a light is shined on them. This fact can be used to find alligators in the dark.
An average American alligator's weight and length is 800 lbs. and 13 feet long. According to the Everglades National Park website, the largest alligator ever recorded in Florida was 17 feet 5 inches long (5.3 meters). The largest alligator ever recorded measured 19 feet 2 inches (5.8 meters) and was found on Marsh Island, Louisiana. Few of the giant specimens were weighed, but the larger ones could have exceeded a ton in weight. The Chinese Alligator is smaller, rarely exceeding 7 feet (2 meters) in length.
Considering alligator's lifespan, it is usually estimated in the rank of 50 years or more. The specimen from Belgrade ZOO, Serbia, named "Muja" was its inhabitant from the opening in 1936, and is still alive and very vigorous (it survived both the Second World War and the NATO bombing n 1999). Therefore, it must be at least 80 years old, although not more than 12 feet long. www.beozoovrt.izlog.org
Habitat
There are only two countries on earth that have alligators: the United States and China.
The American Alligators normally live in the states along the coast of the Gulf of Mexico, Texas, Oklahoma, Louisiana, Mississippi, Alabama, and Florida as well as Arkansas, Georgia and the Carolinas. However in the last few years, the alligators range appears to be increasing northward. Alligators have been seen as far north as Memphis, Tennessee, , presumably arriving there by swimming up the Mississippi River. The majority of American Alligators inhabit Florida and Louisiana. In Florida alone there are an estimated more than 1 million alligators. The United States is the only nation on earth where both alligators and crocodiles live side by side. American Alligators live in freshwater environments, such as ponds, marshes, wetlands, rivers, and swamps.
The Chinese alligator is endangered and lives only in the Yangtze River valley though currently Rockefeller Wildlife refuge in southern Louisiana has several in captivity in an attempt to preserve the species. There are only estimated to be a couple of dozen left in the wild. There are many more of these alligators in zoos around the world than in the wild.
Behavior
Large male alligators are solitary, territorial animals. Smaller alligators can often be found in large numbers in close proximity to each other. The largest of the species (both males and females), will defend prime territory; smaller alligators have a higher tolerance of other alligators within a similar size class.
Although alligators have heavy bodies and slow metabolisms, they are capable of short bursts of speed that can exceed 30 miles per hour, though this could more properly be classified as a short fast lunge rather than a dash. Alligators' main prey are smaller animals that they can kill and eat with a single bite. Alligators may kill larger prey by grabbing it and dragging it in the water to drown. Alligators consume food that cannot be eaten in one bite by allowing it to rot or by biting and then spinning or convulsing wildly until bite-size pieces are torn off. This is referred to as the "death roll."
Most of the muscle in an alligator's jaw is intended for biting and gripping prey. The muscles for opening their jaws are relatively weak. As a result an adult man can hold an alligator's jaw shut with his bare hands.
Diet
Alligators are opportunistic feeders, eating almost anything they can catch. When they are young they eat fish, insects, snails, and Crustaceans. As they grow they take progressively larger prey items, including: larger fish such as gar, turtles, various mammals, birds, and other reptiles. Their stomachs also often contain gastroliths. They will even consume carrion if they are sufficiently hungry. Adult alligators can take razorbacks and deer and are well known to kill and eat smaller alligators. In some cases, larger alligators have been known to hunt the Florida panther and bears, making it the apex predator throughout its distribution. As humans encroach onto their habitat, attacks on humans are few but not unknown. Alligators, unlike the large crocodiles, do not immediately regard a human upon encounter as prey.
Unfortunately, human deaths caused by alligators have increased. While there were only 9 fatal attacks in the U.S.A. from the 1970 to 2000, 11 people were killed by alligators from 2001 to 2006. More deaths occurred in this 5-year period than did in the previous 30. For a long time people have been taught that alligators fear humans, which is true, but this has led some people to be foolhardy and enter the animal's habitat in ways that provoke aggression.
Reproduction
The maturity of the alligator is dependent more upon the size of the animal than its age. An alligator is generally considered mature when it reaches a length of six feet or more. They are seasonal breeders. The mating season is in spring when the water warms. The female builds a nest of vegetation that rots, incubating the eggs. Sex is fully determined at the time of hatching and irreversible thereafter, and depends on the temperature of egg incubation, temperatures 30 °C producing all females, 34 °C yielding all males. The temperature-sensitive period is between 7 and 21 days of incubation. Natural nests constructed on levees are hotter (34 °C) than those constructed on wet marsh (30 °C), thus the former hatch males and the latter females. The natural sex ratio at hatching is five females to 1 male. Females hatched from eggs incubated at 30 °C weigh significantly more than males hatched from eggs incubated at 34 °C. The mother will defend the nest from predators and will assist the babies to water once they hatch. She will provide protection to the young for about a year if they remain in the area.
Farming
Alligator farming is a big and growing industry in Florida, Texas and Louisiana. These states produce a combined annual total of some 45,000 alligator hides. Alligator hides bring good prices and hides in the 6-7 foot range have sold for $300 each, though the price can fluctuate considerably from year to year. The market for alligator meat is growing and approximately 300,000 pounds of meat is produced annually. According to the Florida Department of Agriculture, raw alligator meat contains roughly 200 calories per 3oz serving size, of which 27 calories come from fat.