The efficacy of TM satellite imagery for rapid assessment of Chihuahuan xeric habitat intactness for ecoregion-scale conservation planning

A critical step in designing effective conservation landscapes is the identification of relatively intact natural habitats. Satellite remote sensing has been effectively used to distinguish relatively intact and degraded forests at a number of scales. However, the utility of remote sensing data for rapid and cost-effective assessments of habitat intactness across large arid regions has not been adequately tested. To this end, we tested the ability of TM imagery to rapidly discriminate different levels of habitat degradation across large regions of the Chihuahuan Desert. We were able to identify relatively intact habitat in many cases. However, degraded habitat was often misidentified as relatively intact. The use of both mid- and late-season imagery provides some improvement by highlighting phenological differences among the intactness classes. Overall, low vegetation cover and inter- and intra-seasonal variability diminish the utility of TM imagery for large-scale conservation planning in the Chihuahuan Desert