Threatened and Endangered Species on U.S. Department of Defense Lands in the Arid West, USA

Abstract

Department of Defense (DOD) lands in the arid western United States provide important habitat for many threatened and endangered species (TES). We explore the status of these species and evaluate threats to their survival and recovery. Thirty-two military sites located in the Chihuahuan, Sonoran, Mojave, and Great Basin deserts collectively support 34 listed and candidate species and one delisted species. We assess the relationship between the status of these species and land degradation by categorizing species according to major habitat type and enumerating the major threats to their survival and recovery. Habitat loss and degradation due to increasing human activities throughout the region are the most significant factors is affecting these species. Urban and suburban development, agricultural conversion, and over-grazing are most important among Arid Grassland/Desert Scrub species, while hydrologic alternation is notable among Riparian and Aquatic species. Nonnative species impact TES through habitat modification, as well as direct predation and competion. Specific conservation issues are discussed for selected species. While military disturbances have the potential to impact many of these species, poor watershed management practices of the past and the influx of humans are primarily responsible for the current status of TES and the ecosystems upon which they depend. Their continued survival and recovery requires coordinated conservation activities at the regional level.