POPULATION METRICS AND USE OF SALTCEDAR (TAMARIX) HABITATS BY COMMON SIDE-BLOTCHED LIZARDS(UTA STANSBURIANA)

摘要

During 2009 and 2010, we observed common side-blotched lizards (Uta stansburiana) in two types of vegetation along the Virgin River in Nevada and Arizona: monotypic stands of nonnative saltcedars (Tamarix) and mixed stands of cottonwoods (Populusfremontii), willows (Salixgooddingii), mesquites (Prosopis), and saltcedar trees. Using mark-recapture techniques, parameters were recorded from 233 individual lizards. We detected no significant difference in parameters between monotypic stands of nonnativesaltcedars and mixed vegetation. However, lizards selected habitats having a more open vegetative structure and parameters were correlated negatively with canopy cover. Greatest canopy cover occurred in sites having >65% stem counts for saltcedar trees.Our results suggest that common side-blotched lizards use habitats with similar structural characteristics in both mixed and nonnative vegetation, and that they avoid sites with dense canopy cover as in the densest stands of saltcedars.