Structural Characteristics of Forest Stands Within Home Ranges of Mexican Spotted Owls in Arizona and New Mexico

Aspart of a set of studies evaluating home-range size and habitat use of radio-markedMexican spotted owls (Strix occidentalis lucida), we sampled structural characteristics offorest stands within owl home ranges on two study areas in Arizona and New Mexico. Study areas were dominated by ponderosa pine (Pinus ponderosa)-Gambel oak (Quercus gambelii) forest (Arizona) or mixed-conifer forest (New Mexico). We describe structural characteristics offorest stands used by spotted owls for both foraging and roosting, in terms of central tendencies and variability in structural characteristics among stands. Our results indicated that stands used forforaging were more variable than stands used for roosting. Observed distributions of structural variables were consistent with recommendations in the recovery plan governing management of owl habitat with a few potentially important exceptions. We also provide additional recommendations for application in forest management, based both on observed data and on extensive collective experience with the owl and its habitat. West. J. Appl. For. IS(3): 189-1 98. Key Words: Radio telemetry, stand basal area, ponderosa pine, Gambel oak. The need to conserve habitat for the Mexican spotted owl (Strix occidentalis lucida) has exerted considerable influence on management of forested lands in the southwestern United States. Although the Mexican spotted owl occurs in several habitat types, it is closely associated with well-structured, late-successional coniferous forests throughout much of its range (Ganey and Dick 1995, GutiCrrez et al. 1995). This owl was listed as a threatened species under the Endangered