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LEGAL STATUS
FOOD HABITS Alligators are opportunistic feeders. Their diets include prey species that are abundant and easily accessible. Juvenile alligators eat primarily insects, amphibians, small fish, and other invertebrates. Adult alligators eat rough fish, snakes, turtles, small mammals, and birds. Go to the following links for more information: Diet and Condition of American Alligators in 4 Florida Lakes American Alligator Food Habits in Northcentral Florida Diet and Condition of American Alligators in Three Central Florida Lakes
SIZE Female alligators rarely exceed 9 feet in length, but males can grow much larger. The Florida state record for length is a 14 foot 5/8 inch male from Lake Monroe in Seminole County. The Florida record for weight is a 1,043 pound (13 feet 10 1/2 inches long) male from Orange Lake in Alachua County. FWC biologists have published an article on the maximum size of the alligator.
REPRODUCTION Nearly all alligators become sexually mature by the time they reach approximately 7 feet in length although females can reach maturity at 6 feet. A female may require 10-15 years and a male 8-12 years to reach these lengths. Courtship begins in early April, and mating occurs in May or June. Females build a mound nest of soil, vegetation, or debris and deposit an average of 32 to 46 eggs in late June or early July. Incubation requires approximately 60-65 days, and hatching occurs in late August or early September.
SURVIVAL
MORTALITY Eggs: Alligator eggs are susceptible to drowning, being crushed by the female, predation, and other less common calamities. Raccoons are the primary predator, although hogs, otters, and bears have been reported to depredate nests. Juveniles: Small alligators are eaten by a variety of predators including raccoons, otters, wading birds, and fish; however, larger alligators may be their most significant predator. Adults: Cannibalism, intraspecific fighting, and hunting by humans are probably the most significant mortality factors. Diseases and Parasites: Very little information is available in the scientific literature on wild alligator diseases and parasites. They are not believed to be a significant problem for wild alligators.
DISTRIBUTION
Alligators occur from southeast Oklahoma and east Texas on the western
side of their range to North Carolina and Florida in the east.
They prefer fresh water lakes and slow-moving rivers and their
associated wetlands, but they also can be found in brackish water
habitats.
Alligators are ectothermic -- they rely on external sources of heat to
regulate their body temperature. Alligators control their body
temperature by basking in the sun, or moving to areas with warmer or
cooler air or water temperatures. Alligators are most active when
temperatures are between 82° to 92° F (28° to 33° C). They stop
feeding when the ambient temperature drops below approximately 70° F
(21° C) and they become dormant below 55° F (13° C). Alligators
are dormant throughout much of the winter season. During this
time, they can be found in burrows (or "dens") that they construct
adjacent to an alligator hole or open water, but they occasionally
emerge to bask in the sun during spells of warm weather.
The article at this link contains information about thermoregulation in
Everglades alligators.
EVOLUTION The most recent evidence indicates that crocodilians (which includes alligators) and dinosaurs evolved from a common ancestor that existed subsequent to the common ancestor that they share with other reptiles. So, even though alligators are classified as reptiles along with lizards, snakes, and turtles, they are actually more closely related to birds, whose direct ancestors were dinosaurs!
While most reptiles have 3-chambered hearts, the heart of alligators, and all crocodilians, has 4 chambers, a trait shared with mammals and birds. The advantage of a 4-chambered heart is that oxygenated blood and deoxygenated blood are separated, which results in more efficient respiration needed for the high metabolism of endothermic (warm-blooded) animals, and enables different pulmonary (lung) and systemic blood pressures, but is seemly over-complex for ectothermic (cold-blooded) crocodilians. The single ventricle of the 3-chambered reptile heart allows some mixing of oxygenated blood with deoxygenated blood, which may help regulate their metabolic state. Crocodilians have evolved a shunt between the left and right aorta (immediately above the ventricles) to facilitate the mixing of oxygenated and deoxygenated blood. Crocodilians also have a valve in the pulmonary artery that, when closed, forces deoxygenated blood to recirculate through the left aorta, which increases mixing. This increased mixing helps crocodilians transition to a lower metabolic state, and enables them to dive for extended periods. How long can a crocodile stay underwater?
The tell-tale eye-shine of an alligator (and other nocturnal vertebrates) is caused by a layer of cells called the tapetum lucidum (a Latin phrase meaning "bright carpet"). This structure is located beneath the photoreceptor cells (rods and cones) in the retina and reflects light back into these cells to increase the amount of light detected, which improves an alligator's vision in low light conditions. In alligators this eye-shine is red, but it can be different colors in other species. For more information, see the documents at the links below.
Texas Parks and Wildlife: Eyeshine Comparative morphology of the tapetum lucidum
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