This Gila monster appeared on a hot, late August afternoon, seeking shade behind my mini-split AC unit. Note the large head, a characteristic of adult male Gila monsters. This one measured 18 1/2 inches in length. They are always welcome here, as are all native reptiles, including the rattlesnakes that do us a great service by keeping a very destructive mouse population in check. (Certain local species of mice do major, costly damage to the electrical systems of vehicles, chewing the wiring as if it were gourmet mouse candy.)