Lizard microhabitat and fire fuel management

Abstract

For many species, dead vegetation is important microhabitat necessary for survival and reproduction. We compared the use of three categories of trees: living, dead standing and dead prone, within and among four species of phrynosomatid lizard (Sceloporus undulatus, Sceloporus graciosus, Urosaurus ornatus, and Uta stansburiana) on the Colorado Plateau during 1990, 1992 and 2000. All four species used dead trees (both prone and standing) more frequently than live trees, despite an opposite pattern of availability. U. ornatus used dead standing more often than dead prone trees, reflecting this lizard's arboreal nature. Tree use did not differ among lizard species, and the lizard species by tree category interaction was not significant. Current policy mandates the removal of dead vegetation and debris on US Federal lands as basic maintenance in order to decrease fire risk. Active removal of “fuel” may limit the local distribution, abundance, and diversity of these lizards, which include dead trees in their microhabitat for shelter, perching, foraging, courting, and defending territories.