An Ecological Model for the Protection of a Dune Ecosystem

Abstract

A once common inhabitant of a 500-km2 sand dune system near Palm Springs, California (U.S.A.), the Coachella Valley fringe-toed lizard (Uma inornata), is restricted to the loose, aeolian sand habitat of that region (Stebbins 1944). Human development that began in the 1950s and accelerated through the next three decades created barriers to sand movement that have altered the habitat. As a result, the lizard was listed as threatened by the federal government in 1980. The lizard's listing as a threatened species set in motion a series of actions that resulted in the creation of the Coachella Valley Preserve System in 1986. One of those actions was the development of an ecological model to guide the design of the preserve system. The ecological model, which became the basis of the Coachella Valley Habitat Conservation Plan, was used to delineate which lands would be preserved and which would be available for development. The focus was on protecting the natural processes that create and maintain the dune ecosystem, not on the lizard alone. Although not oblivious to ownership and political patterns, designers of the preserve system emphasized the dynamic nature of the sand dune ecosystem and developed a protection plan to incorporate large-scale patterns. Protected lands were designed to encompass ecosystem processes, including wind and sand corridors, as well as the sand dune habitat. The Coachella Valley Preserve system was among the first habitat conservation plans (HCP) created under the Endangered Species Act. HCPs have been heralded as a means to reconcile the disparate interests of human development and the habitat needs of endangered species (Bean et al., 1991). The Coachella Valley fringe-toed lizard HCP has been held up as a model for resolving con-