Effects of Habitat Disturbance on Texas Horned Lizards: An Urban Case Study

Abstract:  Disturbance caused by habitat restoration or urbanization can threaten populations of sensitive wildlife species. We examined the effects of habitat disturbance on the ecology of an urban population of Texas Horned Lizards (Phrynosoma cornutum), a species of conservation concern in several states as a result of range-wide declines. We quantified changes in spatial distribution, survival rates, and population size and density over 9 yr (2003–2011) for a P. cornutum population on an urban reserve. The project was divided into three, 3-yr stages based on level of habitat disturbance. Spatial analyses did not support the hypothesis that disturbance associated with restoration activities affected the spatial ecology of P. cornutum on our study site. However, these results were not entirely conclusive due to the logistical constraints of working on a single site with an uncommon species. Survival (n = 147 lizards) was affected by season (inactive-season survival was higher), stage (declining survival...