   Rattlesnakes - July 6, 2011 Jeff Schalau, Agent, Agriculture & Natural Resources University of Arizona Cooperative Extension, Yavapai County Its summer and the rattlesnakes are again active. These unique reptiles deserve our respect. Although they sometimes appear threatening and surprise us, rattlesnakes simply want to be left alone and will usually retreat if an escape route is available. On the other hand, they are venomous and their bite can be life threatening. It is important that we be aware of their risks, behaviors, and act responsibly when enjoying the outdoors. Many outdoor enthusiasts regularly kill them on sight. This is not warranted and if we take time to watch for rattlesnakes and give them the space they require, they go on about their business and we can too. Arizona has the thirteen different species of rattlesnakes. In the higher elevations of Yavapai County, the most common species are the western diamond-back, black-tailed, Mohave, and Arizona black rattlesnakes. They are most active from March through October and shelter in abandoned burrows of other animals, brush/woodpiles, and rock crevices. They generally eat small mammals, lizards, and birds. Rattlesnakes use camouflage as a defense mechanism and to help them catch prey. While camouflage makes it difficult for people to see and avoid them, their audible rattle provides a warning most of the time. These rattlesnakes are primarily active in the day and most active in the morning and evening hours (crepuscular) during spring and fall. During the hottest months of summer, they tend to be more active at night. There is some variability between species in their tendencies regarding diurnal/nocturnal activity. When a coiled rattlesnake is encountered it will often remain motionless, presumably to avoid detection. Failing that it may raise the head into a striking pose, rattle, and slowly retreat toward shelter. The rattle itself is made of the protein keratin – the same material found in our hair and fingernails. Rattlesnakes use the "loreal pit," a heat-sensing organ between the nostril and eye to locate prey and potential predators. Rattlesnakes have glands that make venom, much like human saliva glands make saliva. According to Arizona Poison Centers, less than 1% of rattlesnake bites result in human deaths. It is uncanny how many rattlesnake bites occur in males between the ages of 17 and 22 and alcohol appears to be a contributing factor in these cases. Okay, I made up that last sentence, but there is some truth to it. When you hear a young man say “hey, watch this”, injury often follows. Rattlesnakes really should be left alone. The western diamond-back rattlesnake can grow up to 66" long and is the largest rattlesnake in the western U.S. The tail is marked with alternating black and white bands that are roughly equal in width. It is also responsible for more bites and deaths to humans than any other rattlesnake species in U.S. (probably because it very common). The black-tailed rattlesnake can grow up to 48" long and the color can vary greatly from brown or beige to green or golden yellow. The tail is black, sometimes with muted, dark, gray-brown rings. The Mohave rattlesnake can grow up to 50" long and is widely considered most toxic rattlesnake in U.S. It is often confused with western diamond-back. When threatened this snake sometimes exhibits a more dramatic defensive display than other species which includes incessant rattling, elevating the head into a high striking posture, and frequent striking before retreating toward the nearest shelter. The Arizona black rattlesnake can grow up to 42" long. Young are vividly patterned and can look very different from adults which are usually solid black with thin white, yellow, or orange crossbars on the back. In my experience, Arizona black rattlesnakes seem to be very common on Mingus Mountain. Some precautions that should be observed are: use a flashlight while outside on warm evenings so you can see ahead of you; clear walkways of brush and keep them brightly lit; control rodents and other prey species around your home; fill all rodent holes in your yard; and avoid feeding birds right next to your home and outbuildings as this will attract rodents that attract snakes. If bitten, follow the following precautions: remain calm; remove jewelry, watches and restrictive clothing from the affected area; keep the bitten extremity below heart level; decrease activity as much as possible and get to a medical facility without delay; and DO NOT apply ice to the affected area, use incision, tourniquet, or electric shock, or administer alcohol or drugs. I have included links to photos and additional information on the web version of this column. Follow the Backyard Gardener on Twitter – use the link on the BYG website. If you have other gardening questions, call the Master Gardener line in the Camp Verde office at 928-554-8999 Ext. 3 or e-mail us at cottonwoodmg@yahoo.com and be sure to include your name, address and phone number. Find past Backyard Gardener columns or provide feedback at the Backyard Gardener web site: http://cals.arizona.edu/yavapai/anr/hort/byg/. Arizona Rattlesnakes (Arizona Game and Fish Department) www.azgfd.gov/w_c/arizona-rattlesnakes.shtml Reptiles and Amphibians of Arizona (Partners in Amphibian and Reptile Conservation) www.reptilesofaz.org/index.html Venomous Wildlife (University of Arizona Cooperative Extension) cals.arizona.edu/pubs/natresources/az1481g  |