The gopher snake, or Pituophis catenifer, is a common, non-venomous constrictor widespread across North America, inhabiting environments from deserts to woodlands. While many snakes produce a quiet hiss by simply expelling air, the gopher snake is famous for a loud, dramatic auditory display. Gopher snakes do hiss, but the resulting sound is far more intense and complex than the typical snake expiration. This powerful noise is central to the snake’s defensive strategy, which contributes to its frequent misidentification.
The Mechanism of Sound Production
The uniquely loud sound produced by the gopher snake is not generated by a simple rush of air over the glottis, the opening to the windpipe. The genus Pituophis possesses a specialized anatomical structure within its larynx that modifies the expelled breath. This sound is created with the help of a cartilaginous structure called the laryngeal septum, which acts much like a vocal cord.
When the snake forcefully exhales, air is channeled through this narrow, flexible shelf of tissue located within the glottis. This specialized structure vibrates in the passing air stream, amplifying and modulating the sound. The resulting noise is a harsh, raspy sound often described as a loud blow or a bellow, significantly louder than the quiet hiss of most other snake species. This physiological adaptation transforms a simple defensive breath into an intimidating acoustic warning.
The Purpose of the Defensive Hiss
The hissing is a primary component of the gopher snake’s defensive display, employed when the animal perceives a threat. The loud sound is immediately accompanied by a change in posture designed to maximize intimidation. The snake inflates its body to appear larger and often coils into an S-shape, mimicking the ready-to-strike position of a pit viper.
The gopher snake also flattens its head, temporarily altering its shape from rounded to a broad triangle, which enhances the visual bluff. The loud, harsh hiss serves as an auditory warning intended to startle or deter a potential attacker without engaging in a physical confrontation. This entire sequence of behaviors is a form of Batesian mimicry, where a harmless species imitates a dangerous one for protection.
Distinguishing Gopher Snakes from Rattlesnakes
The gopher snake’s defensive display, which includes the loud hiss and rapid tail vibration, often leads to misidentification as a rattlesnake. When the snake vibrates its tail against dry leaves or debris, the resulting buzzing sound can be nearly indistinguishable from a true rattle. Many people mistakenly kill gopher snakes out of fear, believing they are eliminating a venomous threat.
Several distinct features allow for differentiation between the two species. The most definitive characteristic is the tail: gopher snakes possess a long, tapered tail that ends in a point, lacking the segmented, keratinous rattle found on a rattlesnake. While a gopher snake flattens its head only when threatened, a rattlesnake has a permanently triangular head shape due to its venom glands. In a relaxed state, the gopher snake’s head is noticeably narrower than its body.