Reptile Vocalizations

From the chirping of geckos to the haunting hisses of snakes, reptiles produce a mesmerizing symphony of sound. Their sounds reveal a vast and sophisticated means of communication that helps them mark territories, attract mates, and navigate their complex natural environments.


Researchers have recently shown that hissing lizards are able to adjust their advertisement calls in relation to ambient noise levels. This is the first time that nonavian reptiles have demonstrated such vocal flexibility.


A lot of people think that snakes are deaf because they don’t have eardrums, but the truth is that they are able to hear airborne sounds. A new study has shown that snakes can sense sound vibrations through a mechanism in their skulls that acts as a sort of substitute for the eardrum. This system consists of a thin plate of bone (the quadrate bone) and a columella, which lies on top of it. Sound pressures cause the columella to vibrate, which then transmits these vibrations to the snake’s brain.

While the vast majority of snake sounds are hisses, rattling noises are also common. These sounds usually indicate aggression or other threats. Venomous snakes may even hiss and rattle in unison, which can be a very effective warning to potential predators. Non-venomous snakes also communicate through body language, such as curving up or inflating their heads to appear larger and more threatening.

A University of Queensland-led team has discovered that pituophis snakes can create low-frequency rumbling sounds. These sounds are probably generated by tensing and relaxing their vocal cords, which causes them to resonate. Unlike other reptiles, pituophis have a single vocal cord rather than the usual paired ones, which is responsible for the range of sounds that they make. These snakes are able to produce a low, resonant bellow that can be heard over long distances.


In the wild, gopher tortoises (Testudo marginata) emit a variety of vocalizations during mating displays. These sounds include grunts, roars, whimpers, and bellows. Researchers used an acoustic unit placed at the “apron,” or entrance, of tortoise burrows in conjunction with a Bushnell wildlife camera to record audio and video of interactions.

Male tortoises hiss during the mating process to signal that they are ready for mounting. Hissing can also serve as a warning to other males. Females may respond to the call by increasing the intensity of their mounting behavior. Male mating success correlates with the number of calls emitted during the mounting display.

Tortoises also produce a low gurgling sound. This noise usually indicates that the reptile is suffering from respiratory illness, and it should be taken to a vet immediately. Other signs of respiratory disease in tortoises include discharge from the nose, swollen eyes, sneezing, wheezing, and lethargy.

Tortoises can also make a hissing noise when their shell is being squeezed. The sound is made when air can’t flow freely, and the resulting pressure causes the tortoise to inhale. It can also be caused by an object stuck in its nostril. In any event, hissing is a sign that the tortoise is stressed and should be given space. It is important to provide a clean, warm enclosure and proper medication.


Frogs are among the most diverse groups of vocally-communicating reptiles. They produce a wide range of stereotyped sounds that advertise their location, signal mating readiness and willingness to defend territories. They are able to recognize the calls of direct territorial neighbors and ignore them to conserve energy, but they will respond aggressively to an intruder’s call.

Males make a series of croaking sounds to establish their territory and encourage intruders to move away. They also emit distress calls, which sound like a high-pitched scream and can be heard a mile away. Frogs can tap on solid surfaces as well, to communicate with a distant mate or other frogs, and some species of frogs make underwater vocalizations.

Musical frogs, such as the canyon tree frog (Dryophytes avivoca), have a beautiful, melodious call, which lasts half a second and is repeated every couple of seconds. Their aggression call is a stuttering trill that rises in pitch at the end, and they give a squeaky peep when calling from shrubs and trees during the rainy season.

The tinkle of the little grass frog (Pseudacris ocularis) is often heard throughout the year in woodland wetlands, forested ponds and roadside ditches in the Coastal Plain. These small, nocturnal amphibians are very sensitive to ambient noise and adjust their calls according to the conditions. A recent study found that the first note of a frog’s advertisement call is more important for its effectiveness than later notes, and that early experience influences a frog’s call patterns.


Crocodiles are surprisingly vocal animals and they use their sounds to communicate with other crocodiles. They roar for a variety of reasons, including to attract mates and to alert other predators that they are nearby.

The roar is a low, deep, and repetitive sound that can be heard over long distances. It can be produced from the crocodile’s mouth, the throat, or the chest. It can also be produced with the tongue or by moving the chin. It is usually accompanied by a clench of the jaws.

A crocodile’s roar can be distinguished from the sound of an alligator or snake because it has more energy behind it. A roar is also lower in pitch than a bark.

Another way that crocodiles communicate is with within-clutch vocalizations. They produce calls while still inside their eggs and they are responsive to the calls of their siblings. This within-clutch communication helps to synchronize hatching.

Researchers have been able to record crocodiles’ underwater vocalizations and they have found that the reptiles use different frequencies of sound to locate the source of the call. One set of chirps was played four times over 11 seconds. The other set of chirps was a bit longer and included higher frequency sounds that were not detected by the crocodiles. The researchers analyzed the behavioral responses of two crocodiles to determine how they used the information in these acoustic signals to locate the source of the calls.