General Distribution
The western diamondback rattlesnake is widely distributed in the Colorado Desert of
California up to 600 m (2000 ft) in elevation, and perhaps higher in a few isolated locations. In
other parts of its range it reaches an elevation of 3000 m (10,000 ft). It occurs in a wide
variety of desert habitats, both on flats and in foothills, and prefers brushy areas. It is often
common in riparian habitats. In California this snake is not as common as in the eastern parts
of its range. A frequently nocturnal species, the western diamondback can be active any
month of the year when temperatures are mild to warm, but is most active in spring and
summer (Stebbins 1954, Klauber 1972). This snake is large, aggressive, has a complex venom and,
therefore, is considered one of the most dangerous snakes in North America. Extreme
caution should be exercised in handling this snake. Habitat Requirements
Heavy brush is the most commonly used cover, but other objects such as logs,
rocks and debris are used. Rodent burrows are often used for refuge. Boulder piles and rock
outcrops are occasionally frequented (Stebbins 1954, Klauber 1972).
Young are born live and thus a quiet, protected place is required such as a
rodent burrow. Free water is probably not required.
This species is widely distributed in brushy lowlands where larger vertebrate prey
(rabbits, rats, etc.) can be obtained. It occurs in smaller numbers at higher elevations, on
drier flats and in sparser vegetation. Reproduction
Western diamondbacks mate as early as late March and sometimes again
in the fall. The young are born in late summer. They are born alive and broods range from 6
to 23 young, averaging 9 (Klauber 1972). Daily/Seasonal Activity
When temperatures are mild this species can be active during the day,
especially in the morning. When temperatures are higher it is more frequently encountered at
dusk and at night. It can be active any month when temperatures are mild to warm, but spring
and summer are the periods of greatest activity (Stebbins 1954, Klauber 1972). Diet and Foraging
The prey are struck and envenomated. Death follows rapidly and the prey is
consumed. This snake takes small- to medium-sized vertebrate prey, such as rabbits,
rodents, birds and lizards (Gloyd 1940, Stebbins 1954). This snake is usually found in brushy
habitats, where these prey items are most numerous. Territoriality/Home Range
Nothing is known concernlng the home range of this species, but other
rattlesnakes are known to move considerable distances. Predator-Prey Relations
This species is probably taken by roadrunners, eagles, other avian predators, and
possibly by mammalian predators. Kingsnakes may take young diamondbacks. Literature Cited
Gloyd, H. 1940. The rattlesnakes, genera Sistrurus and Crotalus. Chicago Acad. Sci. 266pp.
Klauber, L. M. 1972. Rattlesnakes: their habits, life histories, and influence on mankind.
2nd ed. Univ. California Press, Berkeley. 1533pp.
Stebbins, R. C. 1954. Amphibians and reptiles of western North America. McGraw-Hill, New York. 536pp.
Information gathered from California DFG - California Interagency Wildlife Task Group
