"Extreme heat does not deter Harris's Antelope Squirrel from vigorous daytime activity. It is agile, scampering over sharp-spined cholla cactus without being pricked, and may sit on top of a cactus to look around. Antelope squirrels dig burrows, usually under desert shrubs such as mesquite, creosotebush, or palo verde, and eat mainly fruit and cactus seeds. Trapping studies indicate the species is found in low densities that vary seasonally. The squirrels are active year-round. They typically breed in December or January and have a litter of 5-9 young about a month later."

Links:
Mammal Species of the World
Click here for The American Society of Mammalogists species account.