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meetMthe alligator.
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> Learn about the Florida Crocodile
(Image: © istockphoto/AndreAshby)
Fortunately for this reptile, it has proven to be a survivor not just in its physiological resilience and adaptation, but in its appeal to the human mammals who affect its destiny. While the animal was threatened by humans, the humans found a way to conserve them in a mutually beneficial fashion. Among its qualities are its high importance to ecosystems, its value in commerce, and its appeal to human intrigue.
It follows then, that its
remarkable increase in numbers would challenge the perspectives and
lifestyles of its human neighbor.
The American Alligator (Scientific name: Alligator mississippiensis) is a reptile among the class of snakes, lizards, turtles, tortoises and the lizard-like Tuatara. It is one of only 25 crocodilians in the world, an order which includes another, smaller alligator from China, 16 crocodiles scattered about the globe, six alligator-like caimans from South America and the slender-snouted Indian Gharial. Like all reptiles, it is ectothermic, which is popularly described as "cold-blooded." This physiological state renders it unable to regulate it's own body temperature from within. The animal must rely on warmth from the sun to maintain a healthy metabolism, keeping its bodily processes working properly and efficiently. (Image above: © istockphoto/LarryLynch) See the entire list of crocodilian species, here. |
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← this pepper sauce and the world's largest alligator have closely in common?
Find out during your live program! Learn more. (Then you can impress your friends with this knowledge when dining out. Just ask your server for a bottle of this, and then start showing off!)
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Size & Appearance (Morphology)
The alligator when hatched may be as small as 8
in./20.3 cm in length. In the wild its average growth rate is about one
foot per year for the first five years or so. In captivity, methods of
growth inducement (particularly for hide producers) are so refined that
an alligator may grow 4 ft/1.2 m or more in the first year.
HIDE. Alligators begin life outside the egg in a hide of distinctive patterns of variations of yellow, brown and black, and tend to lose color as they grow older, affected by solar burn, water tannins and other environmental factors. The result may be a hide of black, gray, brown, or a combination of such. Some believe that alligators are green, but the green color seen on some alligators is only from a covering of algae, duckweed or other vegetation (refer to the photo at the opening of this article for an example). The alligator is one of the most heavily armored animals of them all. Thick bony tiles on its neck, back and tail, called "scutes" or osteoderms, help protect it from attacks by other animals, and have even been known to deflect bullets from some lesser powered guns. (Image: © istockphoto/clark42)
TEETH. Teeth number about 80 in an alligator, and it will regenerate new ones throughout its life. Unlike a crocodile, its lower teeth fit into indentations in the upper jaw when the mouth is closed, revealing fewer teeth. The teeth are conical, being more pointed in younger animals. The tooth shape is necessary especially for grasping and tearing, since crocodilians cannot chew.
In other words, an effort to break free from a large alligator's grasp is equivalent to that of one trying to lift a small truck.
"Drop in any time": The image at right is from a postcard sensationally advertising the intimidating jaws of an 'exotic' Florida inhabitant.
The tongue inside resting in the lower jaw does not
extend from the alligators mouth like ours does, but it is good for
holding food, and for mother 'gator to carry her babies comfortably in
her mouth. The tongue also has the all-important taste buds like ours
do. The tiny dark dots on the 'gator's jaw look like freckles but they're actually very sensitive buttons called integumentary sensory receptors (see image at right). These enable the animal to sense movement in the water, such as fish swimming nearby. This field of receptors lining the jaws is just another adaptation that makes the alligator such a superb hunter. Interestingly, the crocodile has these receptors all over its body.
EYES. Alligators see quite
well at night, due to the
tapetum lucidum (TaPEETum LOOsidum), a structure beneath its array of light
receptors in the retina of the eyeball that enhances light reflection.
This also gives the alligator its famous reddish-orange reflection in
the dark when light is shined on it (see the image below). The pupil of the eye opens to a
large circle in darkness(in order to catch as much light as possible),
and to a cat-eye-like slit in the light. However, the eyes become darker
in appearance when the alligator grows larger. Did you know that an alligator wears swimming goggles? Its 'third eyelid' is called the nictitating membrane, which closes over its eye as it submerges, giving the animal a view underwater while protecting the eye.
EARS. Their ears are not like ours. Instead of an outward "flap" like humans' have, it has tight, slit-like flap on the sides of the head just behind the eyes, and they will close tightly when the animal submerges.
(Image: © istockphoto/LarryLynch)
NOSTRILS. The alligator can breathe even when it is almost completely submerged, thanks to those two small, curved slits on the upper plane near the tip of the snout. Alligator breathing canals work just as a human's does. They breathe through nostrils and through their throats. When they submerge, the nostrils and a flap in the throat are sealed shut. An alligator can hold his breath for a longtime under water, maybe as long as three hours.
FEET. The alligator has five "fingers" on each front foot and four "toes" on each rear one. Claws on the feet may appear menacing, but they are not sharp, compared to a cat or a bird. They are mostly used for touch and for slow paddling and steering in water.
TAIL. The very powerful tail is used mostly for swimming, being used as a rudder and a power "motor." This tail can also be very dangerous to any attackers, including humans; the tail of a large alligator could easily snap a man's leg.
HEART. The heart of an alligator is a significant feature because unlike almost every other reptile, the organ has four chambers. This complexity enables the cardiovascular system to divert oxygenated blood to the brain to keep it activated (thus keeping the animal alive), enabling the 'gator to hold its breath for long periods, and even to practically "shut down" its brain during hibernation in the colder parts of its natural range. The cardiovascular system can also divert carbon dioxide-rich blood to the stomach to increase the efficiency of digestion after an alligator has taken in a meal.
BLOOD. Scientists are just learning how powerful alligator blood is in resisting infection and disease. An alligator may swim in foul water, or sustain a gaping wound from combat, but in many cases survives. Proteins in its blood are the warriors for the 'gator (see "Economic Impact," below.)
Population
The number of alligators in the wild is impossible to
know. So we depend on biologists to estimate their numbers, which is a
tricky business. Scientists may use studies to factor
into their computations, such as nest counts or nighttime eye-shine
counts (nighttime is when alligators are on the move, making them easier
to count and approach in the dark). In the photograph below, Laura
Brandt of the U.S. Fish & Wildlife Service conducts an alligator count
from atop an airboat.
The American Alligator's combined and ever-increasing numbers among the states making up its range is more than five million.
Distribution
The American Alligator may be found throughout the southeastern United states, from the Florida Keys in the southeast, to the North Carolina/Virginia border to the northeast, over to the southeastern tip of Oklahoma, down to southern reach of east Texas. Its range consists of all the area in between those points, such as Georgia, South Carolina, Alabama, Louisiana, Mississippi, and Arkansas, an area of both sub-tropical and temperate zones.
Individual alligators are found in states outside of its range, as regular news reports attest to. These animals, however, are not native and are released or have escaped from captivity as "pets." In their natural range, alligators are able to adapt to the cold and even to ice-capped water and those former captives loose in the northerly range will perish when the seasons turn cold.
Human Conflict
Twenty-three humans have died in the hundreds of
recorded alligator attacks since documentation of these
Florida, it comes as no surprise, is the most affected by this reality, with its 19 million residents and 82 million visitors sharing the landscape with (and even taking it from) the alligator. The state numbers its 'gator population at about 1.5 million.
Florida and other states in the alligator range have established "nuisance" alligator programs to better manage human-alligator conflict while maintaining protection of the species. (Image: © istockphoto/EEI_Tony)
A directory of state government wildlife authorities who deal with "nuisance" alligator complaints may be found here.
(Image: © Israel Dupont)
Habitat
The semi-aquatic reptile makes its home at almost any body of water and on the immediate surrounding land. Major factors affecting its choice include (in no particular order):
· Proximity to humans, as this condition can serve as a major stressor. However, its desire for a home in limited, untouched habitat may force conditioned behavior in the alligator that desensitizes it to human company, resulting in a willingness to share habitat with people. · Availability of prey. They've got to eat, right? · Access to features that allow it to hide on land, hide in water, such as in dense aquatic vegetation, bask in solar warmth, and rest in shade.
(Image: © Ronald Dupont Jr.)
· For breeding males, water bodies with females. A bull alligator will travel a distance in search of a mate, crossing over dry land or navigating channels of water. · Water movement and temperature. Alligators do not prefer fast-moving water, since this condition makes navigation, hunting, and breeding more difficult. A warm lake is obviously much more appealing to a 'gator than a chilly, spring-fed river; though, at 72° F (22.2° C), a chilly river may feel better than the chilly air during winter. Hence, the alligator's resilience and ability to adapt (although limited) renders its comfort relative. (Image: © istockphoto/pmstephens)
Diet
Simply put, an alligator will eat practically anything that contains meat, as long as it is of the right size. Given the plethora of prey available in its temperate region, it will eat fish, crustacean, birds, frogs and toads, other alligators, snakes, turtles, small animals, and, if it is hungry and large enough, will capture and eat large mammals as well. In its first three years or so, from hatching to
juvenile, it will progress from taking smaller prey like insects,
crayfish, minnows, frogs and toads, to seizing progressively larger fish
and birds, small mammals like mice, rats and rabbits, birds, snakes, and
others relative to their size. An adult 'gator will accept the same meals, but with its mass and power in its favor, will opt for bigger game if it pleases. Its opportunistic nature, however, prompts it to go for the manageably-sized prey.
The image at right is not a pretty sight, but it represents the reality of an alligator's life, and the fact that it only has its jaws to capture food. (Image: © istockphoto/Saracino)
Eating will pause during the cold months, since the alligator will begin to have difficulty digesting food when temperatures dip below 80° F/ 27° C. Going without food for a few months is not a problem, as their slow and efficient metabolism will maintain their energy stores until springtime.
Reproduction
The bull alligator in the image to the left is posed in mid-bellow. (Image: © istockphoto/floridastock)
A mother alligator will begin building her nest in June, usually doing so close to the water. The nest mound, about 3 ft/1m high and twice that size in diameter, is constructed of vegetation debris and soil/mud, the top of which she will scoop out and lay an average of 35 eggs in.
Hatching occurs about 65 days later, with the young breaking free from their eggs and "pipping" or chirping to their mother for assistance. The alligator mother is a most attentive one, and will help her progeny to water and subsequently watch over them for about a year, sometimes longer.
Survival
The alligator is a relatively
long-lived animal, which may reach the age of 50-60 years in the wild
or up to about 80 years in captivity. One of the oldest 'gators ever may
be one that was featured as a juvenile in the 1932 movie, Tarzan the
Ape Man, starring Johnny Weissmuller (see the image below); today,
the reptile movie star appears to be alive and well and living in
Florida.
The American alligator in the long-term outlasted prehistoric animal life to develop into its current form. Its numbers were significantly challenged by man by 1970, who killed it by habitat contamination and for its meat, hide, and perceived threat to the safety of human residency and to the growing real estate claims of agricultural and industrial development.
Even without human pressures, the alligator has a difficult and precarious life in its first few years. Eggs may be drowned in water, mistakenly crushed by the mother, or eaten by raccoons or other mammals. Despite further protection from their mothers after hatching, the onslaught of larger animals like birds, fish, mammals and adult alligators taking them as prey results in only about four of 15 hatched alligators living to adulthood. Once it reaches about three feet in length, its only major predators are larger or stronger alligators--and humans.
The highly desirable alligator was nearly hunted to extinction by the 1960s, and it was only when federal and state governments imposed strict protection laws and the concept of "sustainable use" was implemented that the reptile was able to make its dramatic population boom. Sustainable use involves recognizing the economic value of a species and utilizing a system of conservation that preserves commercial interest so long as the species is preserved (see "Economic Impact", below.)
The sustainable use model is controversial; it is ethically unpalatable to those who oppose using animals as commercial resources, while its proponents point out that is have proven a very effective policy of saving many species which hold economic value, from the approaching extinction.
The alligator was federally listed in 1970 as endangered and by 1987 was declared recovered but "threatened due to similarity of appearance" to the "threatened" American Crocodile. In Florida, the animal was classed by the state as "threatened" in 1974, and downlisted to "Species of Special Concern" in 1979, owing to its remarkable increase in numbers.
States in which the alligator lives have successfully managed 'gator populations though hunts, harvesting and "nuisance" animal programs.
Natural Importance
The alligator's importance to its habitat is so high that it may be referred to as a "keystone" species for multiple reasons, including these:
It regulates animal populations when it takes prey. Natural elements and the balance of their use are sent awry without an apex predator that can eat practically any prey. Too many of any species, such as rabbits or turtles, places burdens on other populations affected, as well as on parts of the habitat.
The nests of alligators are sometimes shared by other reptiles, namely turtles. A turtle will lay her eggs in the lower section of a nest, and leave them. Her eggs will incubate in optimum levels of temperature and moisture, and of course, will be guarded by a fierce mama alligator. Some species of turtle may hatch up to 200 babies, which will enter the ecosystem and fill their own role in it.
Economic Impact
The alligator's natural importance has an immeasurable positive effect on the natural and economic health of its region. Some are understandably opposed to the commercial use of the alligator, but its distinction in generating many millions of dollars for business enterprises makes this worth discussing (and it has been invaluable to the species' conservation, as discussed in "Survival" above). Among these attributes are the following:
· The cultural influence of the alligator is significant. Cultures of today and of centuries past have made the dramatic alligator (and other crocodilians) an important player in the social landscape, be it in religious integration, television and film entertainment, or the symbols of schools and sport teams.
The experience of the presence of a specimen like this leucistic one is an appealing tourist draw and very educational. (This "white" reptile was hatched with a genetic reduction in skin pigment.) (Image: © istockphoto/mcveras)
Recreational hunts bring in revenues for the state government and for the hunters. The panoramic photo above depicts the St. Augustine Alligator Farm as a tourist attraction in the late 1800s. It is still in operation today as an accredited zoological park-- the only one in the world that features all 22 of the alligator's close relatives.
· Alligator body by-products are the biggest markets for alligator use. Virtually all parts of the animal may be sold: meat; hide; eyeballs (for science labs); the skull, teeth, feet, osteoderms (those bony plates in its back) --and even its feces may be sold as souvenirs, as evidenced by the image to the left. · An additional and noteworthy by-product is its remarkable blood, the proteins of which are being studied and tested for its powerful immunity to disease and infection. Some experts tout potential medicinal benefits from the proteins that will be used in a host of new products, from a quick-healing antibiotic to a cure for HIV and AIDS.
One researcher recently performed experiments that identified the alligator embryo's ability to heal its scars by means of a protein called TGFB3. The commercial result: A product for use in the medical and cosmetic industries.
(Image: © Israel Dupont)
Suggested Print & Video Publications
For your convenience, the books and videos below may be purchased in the online Shop. Click on an image to enlarge.
*Find more publications about alligators in the Crocodopolis Bibliography of crocodilian-subject literature, here.
Video
(1986/1993) National Geographic Video; DVD, VHS NTSC; App. 59 mins.
Audubon's Animal Adventures: Alligator & Crocodile Adventures (1997) National Audubon Society, HBO Kids Video; VHS NTSC, 30 mins. [Available on DVD R1 as part of a 3-disc set, Audubon's Animal Adventures (2000)].
*Find more videos in the Crocodopolis Filmography of alligator video presentations, here.
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JAWS.
incidents began. All but one fatality occurred in the state of Florida.
Human population and development is always growing and expanding while
legal protection of the alligator allows the animal's numbers to
flourish; hence, there's bound to be conflict.
·
Level of salinity (salt), since it does not regulate salinity
as a crocodile does. They have been known to settle in brackish waters,
though fresh is preferred. 
·
For mature females, access to suitable nesting area.
As
an irrigation specialist the 'gator will dig water holes
during the dry season, providing much-needed hydration for
animal life. Using its powerful body, it will manipulate mud and dirt
around it, displacing it in order to tap the water beneath, thus
maintaining water depth.
The
alligator may serve as a sentry to nesting birds. A
curious aspect of its regulatory work is it presence among bird nesting
habitat. Birds will nest in trees and brush over the water's edge to
secure a distance from would-be predators seeking to eat their eggs or
young. A hungry raccoon, for instance, may only approach such a limb
from the water, but dares not, lest he become alligator food.
Learn more about alligators and other fascinating crocodilians at
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