As we were leaving the ranch a few days ago, Papa spied a Gila monster on the side of the road. We quickly turned around and chased the Gila monster on foot, trying to get a good photo. He/she was quick, darting under prickly pear and grasses. He/she was about 18" long. Gila monsters are the only venomous lizard native to the United States, but they are so slow that they are not much of a threat.