Under appreciated and sometimes feared, reptiles play an important role in the ecosystem. Lizards and snakes help control insect and rodent populations. In turn, these reptiles become potential meals for birds and mammals.
While most of the animals found here are not considered dangerous, it is worth remembering that any animal may bite if it feels threatened. Please leave all wildlife alone, and enjoy them from a safe distance.
BulllsnakeAlso known as: Gopher snake, pine snake, Sonoran gopher snake, Great Basin gopher snake
Size: Length 36 to 110 inches (3 to 9 feet)
Habitat: Oak and pine-oak woodlands, pine and fir forests, deserts, desert grasslands, cultivated fields
About: These snakes are one of the most common in the US. They help control rodents, and occasionally eat birds and eggs. Bullsnakes use constriction to capture and kill their prey. Typical prey includes 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, which is why they are sometimes 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, western harvest mice, kangaroo rats, ground squirrels, and young rabbits. They have also been known to eat bats in roosts.
They imitate rattlesnakes by coiling up, hissing, and striking, and even vibrate their tails. This helps them escape predators; however, they are not pit vipers (they do not inject venom when they bite). Superficially, these snakes resemble many species of rattlesnakes and are often mistaken for them and killed. Bull snakes are not venomous and do not have rattles on the end of their tail.
Black-tailed rattlesnakeAlso known as: Black-tail, Northern black-tailed rattlesnake, Green rattler
Size: Length 28 to 48 inches
Habitat: Mostly above 3,500 feet, in rocky canyons, ridgelines, pine-oak forests and mesquite grasslands. This snake is found at low regions up to 8,000 feet. It seems to be most abundant in the woodlands.
About: Most black-tailed rattlesnakes are not aggressive. They are especially common along ridgelines and in rock canyons, being active when the sun has warmed the cracks and crevices. Their colors of olive green, yellow and black are brighter than the diamondback, but the pattern is similar. As their name implies, the rattle is black as the body color gradually fades into a solid black tail. The females tend to be larger than the males and have larger & thicker tails.
Like most large rattlesnakes, the Black-tailed rattlesnake feeds mostly on mammals (mice, rats, squirrels, rabbits), but will also consume lizards, birds, and bird eggs. When hunting for prey, this species uses its heat-sensitive organs on the sides of its head to detect infrared heat and flicks its tongue to detect scents in its surroundings. Prey is caught by means of two hollow fangs tucked away in the front of the upper jaw. Upon striking, the fangs are extended. Once the fangs penetrate the skin of the prey item, glands at each side of the head release lethal venom into the prey.
The Black-tailed rattlesnake does not lay eggs, but instead is ovoviviparous or live bearing. Birth usually occurs from July through August with a brood size that varies from 3 to 6. Each time the skin is shed, a new rattle segment is added to the tail. The shedding is essential for growth and wear on the skin. Once the species reaches maturity, the skin is still periodically shed, but the rattle stops developing, and old segments begin breaking off. Rattlesnakes generally have an average lifespan of 17.5 years. The expected lifespan of black-tailed rattlesnakes is unknown.
Crevice spiny lizardAlso known as: New Mexico crevice spiny lizard
Size: Snout-to-vent length of up to 4.6 inches, with a total length of up to 12.2 inches
Habitat: Arid and semi-arid regions with lots of holes and crevices
About: They have a broad, black uninterrupted collar with white borders, a small pale bluish spot just above the shoulder within the black collar, a whitish crossband or series of spots on the rear of the head between the ear openings, and a tail with contrasting black (widest) and white bands. Dorsal body scales may have black edges aligned to form longitudinal black lines. New Mexico Crevice Spiny Lizards have a black, white-spotted top of head, pale body crossbands with black-edged scales. Lower sides of the body may be orangish. Can be differentiated from other spiny lizards in lacking the contrasting black and white banded tail.
Mostly insectivorous with ants, beetles, and grasshoppers common in the diet. Spiders and centipedes have also been reported as food items. Plant material is also consumed, especially among larger lizards.
The reproductive period (mating through ovulation) occurs in fall months with slowed winter embryonic development increasing through spring. Young are born alive in late May-June and females only produce one litter (up to 11 young) per year.
Gila spotted whiptail
Western chorus frog
New Mexico spadefoot toad
Common Reptiles & Amphibians
Last updated: November 14, 2022