Effects of wildland fire on lowland leopard frogs and their habitat in southeastern Arizona

Authors: J. Eric Wallace, Don E. Swann

Year: 2009 (xli)

Abstract

The lowland leopard frog (Rana yavapaiensis) is declining over much of its range in southeastern Arizona, including Saguaro National Park and the nearby Santa Catalina District of the Coronado National Forest. One factor implicated in the decline of frog populations is increased stream sedimentation following large, severe wildland fires. We investigated the impact of wildland fire on frogs and their aquatic habitat in watersheds burned by two major fires in 2003 and in unburned control areas. We surveyed frogs and habitat in both burned and unburned canyons prior to fires and twice after fires. Fires affected frog habitat dramatically and in different ways. Frog abundance and breeding success decreased in watersheds where large areas burned, yet frogs persisted in most canyons, at least over the short-term. Fire and sedimentation are natural processes that may impact leopard frogs and other aquatic species more now than historically due to changes in fire regimes. Consequently, we recommend greater integration of studies of fire effects with long-term monitoring of watershed processes and aquatic species.