However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing, kidney problems (such as change in the amount of urine). This is not a complete list of possible side effects.
They are more active when it is cooler, but they can and do come out of hiding at any time of the day. Here in the desert, Arizona Rattlesnakes can easily overheat and die if they cannot find a cool place to keep themselves cool.
Arizona was admitted as a State on February 4, 1912. In 1850 present-day Arizona had no census coverage. The 1860 population is for Arizona County, New Mexico Territory, which comprised most of present-day Arizona south of the Gila River. Northern and central Arizona first had census coverage in 1870.