Snakes, often perceived as silent, actually produce a surprising variety of sounds. While their movements are typically quiet, many species vocalize, creating distinct noises that serve various purposes. These sounds range from common hisses to remarkably unique vocalizations, challenging the assumption of a silent serpent.
The Primary Sounds of Snakes
Hissing is the most common and recognizable sound produced by snakes. This sibilant noise serves as a general warning, used by many species when threatened. While the basic sound of a hiss is similar across species, its intensity or duration can vary.
Rattling is another well-known sound, most famously associated with rattlesnakes. These snakes create a distinctive percussive noise by vibrating specialized structures at the end of their tails.
Beyond these, some snakes produce more unusual noises. King cobras emit a low growl, differing from a typical hiss. Pine snakes (also known as bull snakes or gopher snakes) can produce a shriek or bellow. Saw-scaled vipers create a rasping sound by rubbing their specialized scales together. Other less common sounds include buzzing, whistling, or a “popping” noise.
How Snakes Produce Sounds
The primary mechanism for hissing involves the rapid expulsion of air from the snake’s respiratory system. Lacking vocal cords, snakes generate this sound by forcing air through the glottis, a small opening at the base of their mouth connected to the windpipe. The speed and volume of this expelled air, controlled by their ribs and lung capacity, determine the hiss’s characteristics.
Rattlesnakes create their rattling sound through the vibration of interlocking keratin segments at the tip of their tail. These hollow segments, made of the same material as human fingernails, click together when the tail is rapidly shaken. Saw-scaled vipers rub specialized, rough-keeled scales along their body to create a rasping sound. Pine snakes shriek as air passes over a laryngeal septum within their larynx. Some snakes, such as the Sonoran coral snake and western hook-nosed snake, produce a popping sound by expelling air from their cloacal vent.
The Purpose Behind Snake Sounds
The primary purpose of snake sounds is defense. Hissing acts as a clear warning signal, deterring potential predators or perceived threats by startling them or signaling agitation. This display can make the snake appear more formidable, encouraging an attacker to retreat. Similarly, a rattlesnake’s rattle serves as a loud warning, alerting creatures to its presence and indicating it feels threatened.
Beyond direct defense, sounds can also serve as a deterrent, signaling a snake’s readiness to defend itself if approached further. While less common, some sounds might play a role in communication, such as territorial displays or subtle signals between individuals, though this area is less understood.
Common Misconceptions About Snake Noises
A common misconception is that snakes are entirely deaf due to their lack of external ears. While they lack outer ear structures, snakes have internal ear mechanisms that allow them to detect vibrations, interpreting them as sound. They are particularly sensitive to low-frequency vibrations transmitted through the ground, such as footsteps, and can also perceive airborne vibrations.
Another common belief is that all rattlesnakes invariably rattle before striking. While rattling is a primary warning, rattlesnakes do not always issue this sound before striking and can choose to strike without it. The idea that only venomous snakes hiss is inaccurate; many non-venomous species also hiss defensively. Snake sounds, regardless of type, are warnings of distress or agitation, not reliable indicators of imminent aggression.