I received the following questions about American alligators, which have spent most of their time in a dormant state since autumn.

Q. How old do alligators get in the wild?

A. Determining the age of wild alligators is difficult because individuals often outlive the research project keeping the records. One of the best records I know of is from a study by Thomas Rainwater, research scientist at South Carolina’s Tom Yawkey Wildlife Center and Clemson University, who recently captured a previously marked alligator believed to be as much as 80 years old now.

Q. My son and I were fishing near Charleston on the first really warm day since last fall and saw a large alligator lying on the shore of a lake. Why would it sit motionless with its mouth open? It was that way when we saw it, so it wasn’t a show for us.

A. James Spotila, a professor at Drexel University, conducted a study on mouth gaping by alligators to determine why these big reptiles, as well as crocodiles, will sometimes sit motionless with their mouth open while they are basking. The behavior has no apparent relationship to the presence of other alligators or humans. Previous studies on Nile crocodiles proposed that gaping was a form of thermoregulation to lower body temperatures. Spotila’s study suggests that the behavior primarily lowers the temperature only of the head and brain. The researchers discovered that the open-mouth display is a mechanism for keeping head temperatures of the animal in equilibrium while the rest of its body is being warmed by the sun during periods of cool air temperatures. Although the physiological process may be different, mouth gaping in an alligator serves as a cooling mechanism similar to a dog’s panting. Written reports of mouth gaping by Nile crocodiles were first recorded in the 5th century BCE.

Q. Whom should I call about an alligator approximately 4 feet long that has been seen along a lakeshore in our neighborhood? We tried throwing something at it, but we can’t get close enough because of the chain-link fence between us and the lake.

A. My suggestion is that you call your friends to come look at it and enjoy being able to see one of these awesome creatures outside of a zoo. I’m not sure why throwing something at it would be a good idea, as you would only scare it away. The wildlife departments of most states, including Alabama, Florida, Georgia and South Carolina where alligators occur naturally, generally do not have time to respond to calls about small alligators. An alligator of that size is usually no threat to humans or even medium-size dogs.

Q. A friend from Alabama said she heard alligators bellowing from a river swamp. Do alligators really do this?

A. Yes. Alligators make deep, resonant vocalizations, especially in the spring when they mate. They are native to southern and central Alabama, and I once heard an alligator bellowing along the Black Warrior River near Tuscaloosa. An adult alligator makes a rumbling sound, much louder and more guttural than a bullfrog, which might also be heard calling in any eastern state.

You can sense the vibrations of a bellowing alligator if you are standing close enough. Female alligators also make a thundering noise. I heard one pair vocalize for days during the spring. My impression is that the female was responding to the male’s bellows. Either would make a bullfrog’s call pale in comparison.

One reason for maintaining a high diversity of wildlife is that many species boost our enthusiasm for the natural world by stimulating curiosity. Alligators clearly spark people’s interest. The number of questions and their variety indicate that people are curious about our native wildlife. And that is good news for wildlife.

Send environmental questions to ecoviews@gmail.com.