Friday

Western Diamondback Rattlesnake (Crotalus atrox)

E-P1040862
While walking in a wash along Lovell Canyon Road on 02/28/2011 with the rock hounds from the Heritage Park Senior Facility, we had a face to face encounter with a Western Diamondback Rattlesnake.  I was walking just a few feet behind one of the ladies in our group when all of a sudden she turned around and started running by me screaming “rattlesnake”. After advancing a few steps forward, the loud buzzing sound of his rattler, coupled with a high rising and very threatening coil was an ample warning not to get any closer. By the time I got my camera focused on him, he had uncoiled, gotten down off the rock and started slithering in my direction, heading for the cover of a large bush. I estimated that he was about 3-1/2 feet in length.

Description: The Western Diamondback is the largest species of rattlesnake common to the Southwest United States. Sizes range from about 10 inches at birth to around 60 inches as an adult. From the sheer standpoint of size it ranks as one of the world's largest and most dangerous snakes; partly because of its wide distribution, this snake accounts for more serious and fatal snake bites than any other North American reptile. 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 brown and has dark diamond shape marks down its back. The diamondback has tubular fangs with which it injects its prey. It sometimes leaves its fangs within its prey however they are replaced 2-4 times a year by a reserve set. Because it is a ‘pit viper’, it  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 Western Diamondback rattlesnake's habitat is varied, but the most likely areas where they can be found are among cactus, mesquite, in and about rocky terrain, limestone outcrops, thick brush and throughout dry, rocky, shrub covered terrain where they can conceal themselves in cracks in the rocks and in holes in the ground. The western diamondback can climb small trees and is an accomplished swimmer. They can be found in central and western Texas, through southern New Mexico and Arizona, southern Nevada and into southern California. The diamondback primarily feeds on small rodents, rabbits, birds, and almost anything alive that can be swallowed whole. 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.

Mating of the Western diamondback rattlesnake occurs in the spring after they hibernate. After a gestation period of about 167 days they can give birth to anywhere from 10 to 20 young. After only a few hours they leave the mother in search of food on their own, resulting in a very high mortality rate.