Urban Ecology of Desert Spiny Lizards
School of Natural Resources and the Environment
University of Arizona
Urban development disrupts wildlife species because it limits the natural habitats that they once inhabited. It is important to understand how the disruption of a natural habitat due to urban development affects different wildlife species, because strides can then be made to create buildings and areas that still cater to the preservation of that wildlife. An urban population of Desert Spiny Lizards (Sceloporus magister) was studied on the University of Arizona campus. We readily observed S. magister to be abundant at several sites, including in the vicinity of Old Main and Yuma Residence Hall. Lizards were captured using a noose attached to a long, telescoping fishing pole. We weighed, measured, determined sex, and obtained temperature and humidity data on all lizards captured. Microchips (PIT-tags) were implanted under the skin of lizards to allow for individual identification. Small, 1.4 gram radio transmitters were attached to the backs of selected lizards, allowing a total of 10 lizards (1female and 9 males) to be radio- tracked from August to October. Individuals will continue to be monitored throughout the year. Up to six different lizards were radio-tracked at a time, with surveys occurring six times per week in the morning, afternoon, and evening. UTM coordinates were recorded using handheld GPS receivers each time a lizard was located. The location data were used to determine activity patterns and home range characteristics, mapping the lizards' movements on Google Earth. On average, the home ranges of the lizards were 1,225.87 square meters, revealing that these lizards do not regularly travel long distances. Our results also indicate that lizards were more active in the summer than in the fall, and that the lizards maintain exceedingly small home ranges. Time was also spent observing their behaviors, such as push-ups and head bobs, which are associated with territoriality. We plan to continue this study throughout the winter and the following year to obtain more data on the urban ecology of S. magister.