The Western Diamondback rattlesnake is the archetypal rattlesnake of the US. The diamondback rattlesnakes are the rattlesnakes responsible for most rattlesnake envenomations in the US, and bites from both the Eastern and Western Diamondback rattlesnake can be deadly.
The Eastern Diamondback rattlesnake Crotalus adamanteus can reach a length of two meters, although the average size is somewhere between 1 and 1½ meters with males larger than females. Its body is patterned with a row of black diamond shaped markings. Its favorite prey are rodents such as rats and squirrels, but they also eat other snakes and birds. It is not afraid to swim, resulting in the Eastern Diamondback Rattlesnake colonizing on many islands along the coastline of Florida. When they bite they are known to inject rather large quantities of venom that must be treated with a large dose of antivenom as well. The Eastern Diamondback rattlesnake is probably the snake responsible for most rattlesnake envenomation in the US1, sharply followed by the Western Diamondback Rattlesnake.
The Western Diamondback rattlesnake Crotalus atroxis one of the more aggressive rattlesnakes in the US as it usually does not back away from confrontations. That is also why people from time to time engage in rattlesnake round-ups where these and other rattlesnakes are forced up from their shelters and killed. Most of their diet consists of small rodents. As adults they have no natural enemies, but young and adolescent individuals are preyed upon by hawks and eagles. A study from 1973 showed 2 that Western Diamondback Rattlesnakes had a bimodal activity pattern with activity during the morning and evening but only very limited activity during the hottest hours of the day.
1. Norris, R. Venom Poisoning in North American Reptiles Campbell J.A., Lamar W.W. The Venomous
Reptiles of the Western Hemisphere. Comstock Publishing Associates pp. 870 (2004)
2. Landreth, H.F. Orientation and behavior of the Rattlesnake, Crotalus Atrox Copeia pp. 26-31 (1) 1973.