Microhabitat use and range size of native and reintroduced populations of Texas horned lizards (phrynosoma cornutum)

Abstract

Texas horned lizards (Phrynosoma cornutum) have declined throughout much their range. Although multiple private and state institutions have made reintroducing this species to restored habitat a high priority, previous efforts have been met with low success and the reasons for outcomes were unknown. The purpose of this study was to compare microhabitat use between reintroduced lizards and a natural population. For three months, I tracked eighteen lizards daily and quantified microhabitat features such as vegetation cover and soil compaction at lizard locations and random points. I compared these data within and between populations to determine if lizards were using microhabitats non-randomly and if they differed in their habitat utilization. Native and reintroduced Texas horned lizards had similar home ranges and daily movement lengths. Microhabitat use differed by time of day and by location. Management for reintroductions should include prescribed burns and increasing the size of the reintroduction site that is managed for this species.