Living Sanibel: The American alligator
The alligator, along with birds, survived the fifth extinction some 65.5 million years ago at the end of the Jurassic period. Its lineage goes back 230 million years. Despite the obvious difference in appearance, the alligator is more closely related to birds than to other cold-blooded animals such as turtles, snakes, and lizards. The alligator builds nests, lays eggs, and remains with its offspring for as long as a year after they are hatched-all characteristics commonly found in birds. Another similarity is that, like birds, the alligator, especially the American alligator, is very vocal.
Because the alligator was over-harvested for its hide and flesh, the species was placed on the endangered species list in 1967. At that time experts estimated that fewer than 400,000 alligators were left in the state of Florida. Restrictions on hunting, strong conservation efforts, and the alligator’s ability to reproduce rapidly all helped to bring this primeval predator back, and 20 years later its status was changed to a species of special concern. Today an estimated 1-1.5 million alligators are living in Florida. Only Louisiana has more, with an estimated 1.5-2 million living in its swamps and bayous.
The American alligator has the strongest bite of any living animal, measured in laboratory conditions at 2,125 pounds per square inch. The only known animal to have ever exceeded that level of bone-crushing jaw power was Tyrannosaurus rex. The alligator can hold its breath and remain underwater for as long as six hours. It does this by shunting off the blood supply to its extremities and circulating all of its blood between its brain and heart. It can survive temperatures as low as 26 F but only for brief periods. Its optimum functioning temperature is 89 F.
The alligator has a high reproductive rate. After breeding in the spring, the male and female separate. The female generally lays one clutch of 20 to 50 eggs, covering them with decaying vegetation that generates heat and serves as an incubator. The warmer eggs (90-93 F) become males, and the cooler eggs (82-86 F) become females. Hatchling mortality is very high, with 93 percent succumbing to predation before reaching sexual maturity around seven years of age. Almost every animal living in the wetlands habitat eats alligator eggs or hatchlings, including herons, egrets, raccoons, otters, snakes, bobcats, panthers, bears, fire ants, fish, crocodiles, and other alligators.
The alligator has a unique relationship with birds, and nowhere does that play out more dramatically than in rookeries. Most rookeries are located on islands or along wetlands where alligators are readily found. In an unusual symbiotic relationship, birds use the alligator as a reptilian sentinel guarding their nests. When a hungry raccoon, bobcat, or rat attempts to swim to an island of nesting egrets and herons, the resident alligator stands ready to kill the predator long before it can reach its intended target.
The alligator has little trouble drowning a predator as large as a Florida panther. The bobcat poses little danger to a creature with a hide as thick and almost as effective as a bulletproof vest. There is a price to be paid for this service, however. The alligator is not above snatching fledglings from low-hanging branches, and if a nestling should end up on the ground or in the water below, the alligator quickly disposes of the wayward chick.
The alligator eats just about anything. It has the strongest digestive acids found in any living creature, capable of converting hair, bone, and teeth into usable proteins. Its diet consists of fish, birds, turtles, snakes, mammals, and amphibians. Hatchlings also eat insects, snails, mollusks, frogs, mice, and rats. A mature bull alligator will eat deer, wild boar, and cattle and will even take down prey as large as black bears and horses.
People are often tempted to feed alligators, but this is not a good idea. Once this pattern is established, the animal equates humans with food, and anyone approaching the reptile is in grave danger.
You should never swim in any southwest Florida freshwater lakes, ponds, or rivers, unless they are clearly marked as safe for swimming. In the water, which is the alligator’s domain, it takes only a small alligator to bite and drown a person. The alligator is capable of very quick attacks and can actually propel itself almost completely out of the water with a few swishes of its massive tail. Since 1948 there have been more than 346 unprovoked alligator attacks on humans in Florida and 22 fatalities. (For more information about alligators and these attacks, read Alligators, Sharks & Panthers: Deadly Encounters with Florida’s Top Predator-Man, published by Indigo Press in 2007.)
Alligators are common throughout southwest Florida. During the rainy season they travel over land and find their way into many residential ponds, golf courses, and manmade canals. They are easy to spot while kayaking along Fisheating Creek, the Peace and Myakka rivers, as well as the marshes and swamps of interior Florida. You should always take care when in the immediate area of any alligator. Female alligators are very protective of their offspring, and males can be aggressive. The alligator is primal and beautiful and with proper management should be a part of Florida for all time.
This is an excerpt from The Living Gulf Coast – A Nature Guide to Southwest Florida by Charles Sobczak. The book is available at all the Island bookstores, Baileys, Jerry’s and your favorite online sites.