Pituophis catenifer

Pituophis catenifer is found from southwestern Canada south to northern New Mexico. Gopher snakes are found from south-central British Columbia and southern Alberta and Saskatchewan, through the central and western United States, and south through Baja California and Sinaloa, Durango, Zacatecas, and Tamaulipas states in Mexico. In the United States they are found from the Pacific coast eastwards to Wisconsin, Illinois, Missouri, Oklahoma, and western Texas. There are 11 subspecies recognized, with some of those proposed as valid species, including P. c. vertebralis, from southernmost Baja California. Several subspecies represent isolated, island forms, including Cedros Island gopher snakes (P. c. insulanus), San Martin Island gopher snakes (P. c. fuliginatus), Coronado Island gopher snakes (P. c. coronalis), and Santa Cruz gopher snakes (P. c. pumilis). (Rodríguez-Robles, 2003)

Gopher snakes are found in a wide variety of habitats, including woodlands, deserts ,agricultural areas (such as cultivated fields), prairies, chaparral, and shrublands. Radiotelemetry studies have shown that, although they are often found near moist habitats, such as marshes and moist woodlands, they prefer to spend most of their time in open parts of those habitats, such as grassland and forest edges. This preference is likely related to foraging activities. (Rodríguez-Robles, 2003)

Gopher snakes range in body length from 180 to 275 cm. They have relatively large heads, narrow necks, and large eyes as compared to most species of similar body length. Gopher snakes are marked with brown to black blotches on a background color of lighter straw to gray. Color patterns vary regionally and often mimic the colors of the dominant cover vegetation in a region. Individuals that are blotched, striped, or even albino are known from wild populations. Their ventral surface is generally white to yellowish, sometimes with dark spots. They usually have a dark line across the face in front of the eyes and from behind the eyes to the angle of the jaw. Gopher snakes have keeled scales and a single anal scale. They have 27 to 37 scale rows at their midbody. Superficially, gopher snakes resemble many species of rattlesnakes and are often mistaken for them. Gopher snakes are not venomous and do not have rattles on the end of their tail. (Waye and Shewchuk, 2002)

Gopher snakes are oviparous and have an incubation period of about 65 to 75 days. When hatched the young measure 30 to 35 cm in length. After hatching, Pituophis catenifer exhibits indeterminate growth. In the first three years growth is rapid, then slows for the rest of their life. (Cowles, 1935; Waye and Shewchuk, 2002)

Males compete for access to reproductively receptive females. Receptive females emit skin secretions that males detect through chemosensation and stimulates mating behaviors. Males will attempt to mate with as many receptive females as they can find. Males and females don't generally associate before or after mating. (Waye and Shewchuk, 2002)

Gopher snakes breed once yearly, usually in June to August. Some females lay two clutches each year. They are oviparous and have an incubation period of 65 to 75 days. Once the 2 to 24 young hatch from the eggs, they are left to fend for themselves. It takes about 4 years for females to reach sexual maturity, but only 1.5 years for males. (Cowles, 1935; Waye and Shewchuk, 2002)

Females lay their eggs in nests, which are sometimes communal. After the eggs are laid there is no further parental care.

The average life span in wild gopher snakes is 12 to 15 years. In captivity they have been known to live for as long as 33 years. (Hiatt, 1998; Waye and Shewchuk, 2002)

Gopher snakes are solitary, except during the mating season. They live alone in dens or other areas that provide adequate shelter. Radiotelemetry studies have found that individuals spend up to 90% of their time in underground burrows. They can also swim and climb well. Gopher snakes are mainly diurnal, but are also active at night sometimes. Like other snakes, gopher snakes go through periods of dormancy when resting or during periods of little food. (Rodríguez-Robles, 2003)

Home range size of four radio-tracked male gopher snakes in California was 0.89 to 1.78 ha. However, they spend the majority of their time in a smaller 0.1 to 0.29 ha section of these home ranges. Individual home ranges rarely overlap with one another. These snakes show a great deal of site fidelity across years. Multi-year studies have found individuals were recaptured about 150 m from their point of release 6 years prior. (Rodríguez-Robles, 2003)

Because they are primarily solitary, there is little communication among Pituophis catenifer individuals. During mating season, females indicate they are ready to mate by releasing skin secretions. Gopher snakes use their tongues and vomeronasal organs to "smell" their surroundings. They also use vision, touch, and sensing vibrations to perceive their environment. (Waye and Shewchuk, 2002)

Gopher snakes use constriction to capture and kill their prey. Typical prey include small mammals, birds, lizards, smaller snakes, insects, and eggs. Prey varies regionally but the primary prey in all areas are rodents and other small mammals. In some areas they prey mainly on gophers (Geomyidae), which is why they are called "gopher snakes." Gopher snakes actively search for prey in their burrows and hiding places. They often follow small mammal runways, and are quite successful in capturing voles (Microtus), western harvest mice (Reithrodontomys megalotis), Peromyscus species, kangaroo rats (Dipodomys), ground squirrels (Spermophilus), and young rabbits (Sylvilagus). They have also been known to eat bats in roosts. Lizards and snakes taken include side-blotched lizards (Uta) and rattlesnakes (Crotalus). They take birds, eggs, and insects occasionally as well. (Rodríguez-Robles, 1998; Rodríguez-Robles, 2003; Waye and Shewchuk, 2002)

Kit foxes Vulpes macrotis , red-tailed hawks Buteo jamaicensis, and coyotes Canis latrans are the most common predators of the gopher snake. They are probably also preyed on by other foxes (Vulpes vulpes and Urocyon cinereoargenteus), hawks (Accipitridae), and large king snakes (Lampropeltis). Gopher snakes are cryptically colored and remain hidden except when actively pursuing prey or basking in open areas. They are large snakes and can inflict a painful bite if harassed. They also behaviorally mimic rattlesnakes by coiling, raising their heads, and rapidly shaking their tails when threatened by a predator or unsuspecting human. Their rattlesnake mimicry can be very convincing and many gopher snakes are killed as rattlesnakes. Non-human predators are likely to be discouraged from attacking gopher snakes when they are mimicing rattlesnakes. (Hiatt, 1998; Waye and Shewchuk, 2002)

Gopher snakes play an important role in the ecosystems in which they live. They are important predators of small mammals, many of which are considered pests by humans. Gopher snakes can greatly reduce the numbers of small mammals in an area.

Parasite surveys have discovered mites (Trombicula arenicola) on gopher snakes, as well as ticks, fleas, and chiggers. Internal parasites include a blood protozoan (Hepatozoon serpentium) and an intestinal parasite (Tritrichomonas batrachorum). (Allred and Beck, 1964; Hilman and Strandtmann, 1960; Honigberg, 1953; Waye and Shewchuk, 2002)

Gopher snakes are important predators on crop pests and play a role in agricultural losses to rodents. They are also good pets if well cared for. Gopher snakes are sometimes killed because they are mistaken for rattlesnakes, which they superficially resemble, but gopher snakes are harmless and beneficial snakes. (Waye and Shewchuk, 2002)

When harassed, gopher snakes can inflict a painful bite, depending on their size. But these snakes are non-venomous and will only bite in self-defense. Gopher snakes are sometimes mistaken for rattlesnakes because of their size, coloration, and habit of wiggling their tail when they feel threatened. (Hiatt, 1998)

Pituophis catenifer is fairly stable throughout its range and is listed as a species of "Least Concern" on the IUCN list. Island populations may be especially susceptible to environmental changes or persecution.