What has been developed in Orange and San Diego County, Calif. are blueprints for other urbanizing communities committed to striking a balance between growth and development and environmental quality and its notion of livability. These plans successfully put in place conservation measures unprecedented in their scope and breadth and yet do so without compromising the economic vitality of the region.

Concern has been expressed that mesquite bosques are disappearing or diminishing in quality, and that the survival of the mesquite mouse is consequently threatened. This study, funded by a grant from the Arizona Heritage Fund to the Pima County Regional Flood Control District, investigated the current distribution of the mesquite mouse by reviewing historical records from museum specimens, examining existing potential habitat at historic locations of the species and elsewhere in the county, and conducting a live-trapping study at 19 sites representing a range of ecological communities with mesquite as a major component.