Microhabitat selection by texas horned lizards in southern Texas

The Texas horned lizard (Phrynosoma cornutum) has declined throughout its r ange. Understanding habitat selection by the Texas horned lizard is an impo rtant factor in its conservation. We examined daily and seasonal habitat re quirements of Texas horned lizards and determined whether habitat selection differed among land management treatments in southern Texas. We used 5 stu dy sites, each with a different burning and grazing treatment. Adult lizard s caught in the study sites were fitted with backpacks carrying radiotransm itters and relocated daily. Habitat characteristics at radio locations and random points 10 m from the lizard were assessed using 50- x 20-cm quadrats . Relocations were made during 3 time intervals (morning, afternoon, evenin g) and 2 seasons (active, inactive). Horned lizards used bare ground and he rbaceous vegetation similar to their availability in the morning and evenin g for thermoregulation and foraging purposes, but avoided bare ground in th e afternoon. In the afternoons, lizards selected woody vegetation and litte r as thermal refuges and cover from predators. Lizards also appeared less d ependent on herbaceous vegetation and more dependent on woody vegetation an d litter in the inactive season compared to the active season as a result o f increased temperatures. We did not detect differences in habitat selectio n among land management treatments. Habitat management for Texas horned liz ards should focus on creating a mosaic of bare ground, herbaceous vegetatio n, and woody vegetation in close proximity.