Alligators are ectothermic, or cold-blooded, meaning their body temperatures aren't self-regulating and consistent like a human's. Their body temperatures fluctuate up and down with the environment, and when they become too cold, they can slip into a dormant state. Even unhatched alligators are affected by temperature fluctuations, which dictate whether the young will hatch as males or females.
Alligators rely on warm weather to survive, and are most active when the environment is between 82 and 92 degrees Fahrenheit. While they can survive at temperatures above and below this range, they may spend that time struggling to stay cool or stay warm. This means that alligators have to take an active role in managing their own body temperatures in order to survive, and that they can only thrive in warmer climates, like the southeastern United States. Because temperatures in these areas are so high during the day, alligators living in regions like Florida and Louisiana may be most active at night.
Managing Body Temperature
In order to maintain a healthy body temperature, alligators must proactively seek out environments that keep them warm and cool enough. During the day, for example, alligators typically find sunny spots near the water, where they can sun themselves and absorb heat. Because areas like these can be particularly warm, when the temperature is above 92 degrees, alligators may have to simply sun themselves with their mouths open, allowing heat to escape in the same way that dogs do when they pant.
While alligators can remain active in environments as cool as 71 F, when the temperature drops any lower, they enter a dormant state. During the winter, alligators dig burrows underground, where they remain dormant until temperatures rise in the spring. This dormancy does not necessarily last the entire winter through, though -- if temperatures become unseasonably warm, alligators may emerge from their dens to spend a few hours soaking up sunlight and warming themselves before returning.
Egg Temperature Impact
Body temperature doesn't affect an alligator only after he is born -- his body temperature in the egg can change the course of his entire life. This is because the temperature of the eggs dictates the sex of the young alligators inside. If the nest's temperature is below 86 F, the eggs will yield female alligators. If it's above 93 F, it will yield only males, and if it falls in between those temperatures, it will yield a mix of males and females.
Tom Ryan is a freelance writer, editor and English tutor. He graduated from the University of Pittsburgh with a degree in English writing, and has also worked as an arts and entertainment reporter with "The Pitt News" and a public relations and advertising copywriter with the Carnegie Library of Pittsburgh.