Normally rattlesnakes rattle when a human gets within a certain distance of them, but this guy didn't rattle even when I moved him with a handy creosote branch, which happened to be on the ground nearby. Even though I spent a couple minutes getting him on video, he still never rattled. He briefly coiled between a couple rocks, but after being nudged with the creosote branch he just calmly slithered away, apparently in no particular hurry. My hypothesis is that since the temperature was relatively cool (in the high seventies most likely), that he remained calm. Add thirty or forty degrees to the temperature and he probably would have been rather ill-tempered, which is the normal predisposition for a rattlesnake.