The American Alligator (Alligator mississippiensis) is a member of one of the three families of crocodile–like reptiles. The order Crocodilia are living fossils from the Age of Reptiles, having survived on earth for over 200 million years. Alligators can be distinguished from the crocodiles and ghavial by their head shape and color. Alligators have a wider snout and, unlike crocodiles, teeth in their lower snout do not protrude when their mouth is closed. In addition, adult alligators are black, while crocodiles are brownish or greenish in color.
As with all crocodilians, and the extinct traditional dinosaurs, alligators are of the reptilian branch known as archosaurs. Modern birds are generally viewed at present as living dinosaurs of the maniraptor group. Assuming this is correct, the birds are also archosaurs and thus alligators are far more closely related to birds than they are to lizards, snakes, turtles or the tuatara.
The American Alligator has a large, slightly rounded body, with thick limbs, a broad head, and a very powerful tail. The tail, which accounts for half of the alligator's total length, is primarily used for aquatic propulsion. The tail can also be used as a weapon of defense when an alligator feels threatened. While alligators travel very quickly in water, they are generally slow-moving on land. However, they have the ability to sprint for short distances at speeds of up to 30 miles/hour (48 km/h).
Despite the extensiveness of their shared habitat with humans, alligator attacks on humans are comparatively rare. Most alligators fear humans; attacks on humans are typically a result of the alligator mistaking them for prey. They can also weigh as much as 750 pounds (340 kg).
Sometimes, the alligator may expand its gator hole by digging beneath an overhanging bank to create a hidden den. After tunneling as far as 20 feet (6 m), it enlarges the end, making a chamber with a ceiling high enough above water level to permit breathing. This is not the alligator's nest but merely a way for the reptile to survive the dry season and winters.
The female builds a nest of vegetation, sticks, leaves, and mud in a sheltered spot in or near the water. After she lays her 20 to 50 white, goose-egg-sized eggs, she covers them under more vegetation, which, like mulch, heats as it decays, helping to keep the eggs warm. The temperature at which alligator eggs develop determines their sex. Those eggs which are hatched in temperatures ranging from 90–93 °Fahrenheit (32.2–33.8 °C) turn out to be male, while those in temperatures from 82–86 °Fahrenheit (27.7–30 °C) end up being female. Intermediate temperature ranges have proven to yield a mix of both male and females. The female will remain near the nest throughout the 65-day incubation period, protecting the nest from intruders. When the young begin to hatch they emit a high-pitched croaking noise, and the female quickly digs them out.
The young, which are tiny replicas of adult alligators with a series of yellow bands around their bodies, then find their way to water. For several days they continue to live on yolk masses within their bellies.
Alligators reach breeding maturity at about 8 to 13 years of age, at which time they are about 6 to 7 feet (1.8–2.1 m) long. From then on, growth continues at a slower rate. Old males may grow to be 14 feet (4.2 m) long and weigh up to 1,000 pounds (450 kg)during a lifespan of 30 or more years.
There have been only 9 fatal attacks in the U.S.A throughout the 70's, 80's and 90's. 11 people were killed by alligators between 2001 and 2006; more deaths occurred in 5 years compared to 30 years. This is an early warning. Underestimating the animal's potential leads to these fatal attacks. For a long time people have been taught that alligators fear humans, which is true, but lead some people to be more courageous and enter the animal's habitat.
In May 2006, there were three reported human fatalities due to alligator attacks in the state of Florida. Alligators killed 3 people in 4 days, two of them in the same day. Deaths in 4 days equal the amount of deaths occurred during 10 years in the past. 3 people died in the 90's, 3 in the 80's and 3 in the 70's. One victim was a jogger whose body was found in a canal on Florida's Atlantic Coast; one was snorkeling in a recreation area near Lake George, in the central part of the state; another was found in a canal on the state's Gulf Coast.
Alligators are protective parents, and a very young alligator may have a mother nearby who protects her young by attacking anyone or anything that poses a threat.
As with any large wild predator, those alligators that develop an excessive familiarity with human behavior become extremely dangerous "problem" animals that must be either relocated or destroyed. Alligators are best appreciated at a safe distance for the protection of both persons and alligators; handling of them is best left to well-equipped and trained experts.
When in gator country, it is a safe practice to know which lakes and rivers are inhabited by gators and which are not as it is obviously not wise to swim in such waters. In many areas, signs are posted warning of their presence, but some are not. Evidence of an area being inhabited by gators include alligator slides onshore (these are markers where the belly of the gator has slid down the bank into the water) large piles of muddy sticks and foliage in spring, and of course occasionally seeing the animals themselves. Pet owners should not let their dogs and cats roam too far from home in such areas as these because a hungry gator will take a dog or a cat as a snack if the opportunity presents itself. If one does encounter a hostile one, it is a good idea to watch the tail-it may try to knock you down so it can use its other big weapon, the teeth. Don't panic and don't let it take you into the water. Climb on top of something high up as alligators cannot climb.
A combined effort by the U.S. Fish and Wildlife Service, state wildlife agencies in the South, and the creation of large, commercial alligator farms saved these unique animals. The Endangered Species Act prohibited alligator hunting, allowing the species to rebound in numbers in many areas where it had been depleted. As the alligator began to make a comeback, states established alligator population monitoring programs and used this information to ensure alligator numbers continued to increase. In 1987, the Fish and Wildlife Service pronounced the American alligator fully recovered and consequently removed the animal from the list of endangered species. The Fish and Wildlife Service still regulates the legal trade in alligator skins and products made from them.
Although the American alligator is secure, some related animals — such as several species of crocodiles and caimans — are still in trouble.
Alligators in the Everglades have reduced length to weight ratio, reduced total length, and delayed onset of sexual maturity compared with other parts of their range. The reason for this poor condition is currently suspected to be a combination of low food availability and sustained high temperatures.
Mississippi-Alligator | Alligator d'Amérique | Alligator mississippiensis | אליגטור אמריקאי | Amerikaanse alligator | Aligator amerykański | Mississippinalligaattori | Mississippialligator
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"American Alligator".
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