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.

A number of significant positive and negative economic impacts could result from Pima County's SDCP and related programs, according to an analysis of existing research on large-scale conservation planning undertaken to provide a framework for community decision-making. This report offers no final verdict on the net economic impact of Pima County's current, ambitious initiatives in habitat conservation and growth management. However, it does provide a framework for future assessment and decision-making.

This version of the Major Streets and Routes Plan revises the original plan and the 2004 revisions. Looking ahead to pending updates to the classification systems of towns and cities in Maricopa County, the original MSRP stipulated a periodic review and modification of the street functional classification portion of the plan. This revision incorporates the following changes: (1) as anticipated, many of the communities in the County have updated either their general or transportation plans in the time since the adoption of the first MSRP; (2) a new roadway classification, the Arizona Parkway, has been added to the Maricopa County street classification system and the expressway classification has been removed; and (3) a series of regional framework studies have been conducted by the Maricopa Association of Governments to establish comprehensive roadway networks in parts of the West Valley.