Tuesday, December 27, 2011

American alligator

Alligator scutes, originally uploaded by Elizabeth Smith.

Can you recognize which part of the alligator this is?  They are bony plates with a ridge extending from the center, and pocked with indented irregular spaces.  These bony plates are scutes, or osteoderms, and lie in multiple rows along an alligator’s back, forming a formidable armor.  These scutes are from a legally harvested alligator.  Florida has a Statewide Alligator Harvest Program that allows annual hunting and trapping to manage populations, as well as permitting year-round captures of nuisance alligators.  

At one time, alligator numbers in Florida had so dramatically declined due to over-hunting and habitat loss that biologists weren’t certain the species would recover.  The United States Fish and Wildlife Service placed them on the endangered species list in 1967, and 20 years later populations rebounded enough to have the alligator reclassified.  Besides Florida, alligators can also be found in Louisiana, southern Texas, and parts of Georgia, Alabama, North Carolina, and South Carolina.
Alligators are the largest reptiles in North America and live in freshwater environments: rivers, lakes, ponds, swamps, bayous, and marshes.  They will tolerate a certain amount of brackish water, and can be found near estuaries and bays as well.  Their bulk and short legs make them appear clumsy on land, but they can actually run quite fast for short distances and had even been reported to climb chain link fences!  Alligators are excellent swimmers; their strength, webbed feet, and sleek body design enable them to dive and move swiftly underwater.  One of the ways alligators subdue larger prey is to snatch them from the shoreline and dive for deeper water, holding the hapless meal-to-be underwater until drowned. 

The average male American alligator is 10 to 15 feet long, and weighs between 500 and 600 pounds.  Females tend to be smaller and lighter than males.  A female alligator lays eggs in a shoreline nest of tangled sticks, vegetation, and mud.  She guards her eggs until they're ready to hatch, and will often assist the baby alligators to the water’s edge.  One of the few reptiles to care for its young, mother alligators have been known to aggressively defend their young for more than a year.

Baby alligators have charming black and yellow stripes that will transform over time to the adult’s slate gray/black coloring.  In the wild, an American alligator generally lives to be 35 to 50 years old, but may survive 60 to 80 years in captivity.  They are “cold-blooded,” or ectothermic, and cannot regulate their body temperature like warm-blooded mammals.  When it turns cold in Florida, I often see alligators basking in the sun along the edges of canals and lakes.  During the summer months, they enjoy the cooler temperatures offered by shade or water and are seldom seen.  Sometimes all I see are the bony ridges and protruding eyes just above the water’s surface – easy to mistake for a floating log.  So far this winter our temperatures have been warm and I haven’t seen the alligators sunning themselves as often as last year. 

It amazes me to think that these primordial reptiles are one of our last links to the dinosaurs.  There is only one species of alligator in North America, the American alligator, Alligator mississippiensis.  The common name is corrupted from el lagarto, (the lizard), the name given to it by early Spanish explorers.  There is only one other alligator species in the world, which resides in China.  Crocodiles are a near relative to alligators, with several different species found in tropical habitats throughout the Americas, Asia, Africa , and Australia.  The American crocodile lives in Florida, but in small numbers, and prefers salt water to fresh.  Crocodiles have thinner, longer, and more pointed snouts than the alligator’s more rounded nose and jaw. 

It’s important to remember that alligators are basically primitive eating machines, and should be treated with care and caution.  Humans have no business feeding alligators, and the babies do not make good pets.  

 Alligators have a place and a purpose within the complex and interwoven ecosystems of Florida, and many species depend on alligator water holes in times of drought.  They are astounding creatures, but a terrible force of nature, and not to be treated lightly. 

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