Length: 30 - 84 inches
Weight: 1 - 2 lbs
Offspring: 10 - 20
Life Span: 20 years
Western Diamondback Rattlesnake
The Western diamondback rattlesnake is the largest western rattlesnake. It has a plump body, a short tail, and a broad, triangular head that is very distinct from the body. It can be yellowish gray, pale blue, or pinkish and has dark diamond shape marks down its back. The diamondback has tubular fangs with which it injects its prey. These fangs are often left within its prey but are replaced 2-4 times a year by a reserve set. It is a pit viper and so has a pit organ between its nostrils and its eyes. These organs detect temperature differences between the interior temperature of the snake and the ambient temperature. There is also a rattle at the end of its tail. This rattle is made up of the last scale that is left when it molts. With each molt, it gains a new layer to its rattle. At the same time, older layers fall off.
The diamondback eats small mammals and birds, and sometimes other reptiles, amphibians, fish and invertebrates. It eats every two to three weeks and swallows its food whole. The food is digested as it passes through the body. Its annual water consumption is about its body weight. In very dry areas it also absorbs water from its prey.
Diamondbacks occupy dry, rocky, shrub covered terrain where they can conceal themselves in cracks in the rocks and in holes in the ground. They are found in central and western Texas, through southern New Mexico and Arizona, and into southern California.
The Western diamondback has many predators, including hawks, bald eagles, roadrunners, and wild turkeys.
Diamondbacks are aggressive and easily excitable. However, they usually don't attack offensively. Most of their attacks are brought about because they are highly defensive and they use their rattles as a warning. As winter approaches they move toward hibernating dens. These can be as makeshift as a crevice in a rock or as built up as abandoned prairie dog burrows (usually abandoned when the snakes decide to move in.) During hibernation, several snakes may congregate together. They are generally nocturnal hunters and are less active during the day.
Mating in the Western diamondback rattlesnake occurs in the spring after they hibernate. After a gestation period of about 167 days, 10 to 20 young are born. This birthing process may last from 3 to 5 hours. The young do not stay with the mother for more than a few hours. After that they leave on their own to look for food. The mortality rate is very high among the young.
Western diamondback rattlesnakes possess a pit organ that senses differences in temperature between the snake's internal temperature and the surrounding. This helps it find prey since it can "see" the temperature difference that they create.