Spotted Owl - Plant Communities

Plant Communities

Northern Spotted Owls occur in ponderosa pine/Douglas-fir (Pinus ponderosa/Pseudotsuga menzeizii) forests in the eastern Cascade Ranges of Washington and in Douglas-fir/evergreen hardwood forests in northwestern California. Throughout much of their range they use stands of the following coniferous species: Douglas-fir, western hemlock (Tsuga heterophylla), western redcedar (Thuja plicata), grand fir (Abies grandis), Pacific silver fir (A. amabilis), Sitka spruce (Picea sitchensis) and redwood (Sequoia sempervirens).

California Spotted Owls occur in hardwood, coniferous, and coniferous-hardwood forests. Occupied coniferous habitats include mixed conifer, California red fir (A. magnifica), and eastside pine forests which are composed of ponderosa pine and/or Jeffrey pine (Pinus jeffreyi). Redwood/California bay (Umbellularia californica), ponderosa pine/hardwood, and live oak-bigcone Douglas-fir (Quercus chrysolepis or Q. agrifolia-Pseudotsuga macrocarpa) are hardwood-mixed coniferous forests used by California Spotted Owls. They also occur in hardwood habitats including riparian and oak (Quercus spp.) woodlands. For example, in the Tehachapi Mountains of southern California they occurred in stands dominated by canyon live oak (Q. chrysolepis).

Mexican Spotted Owls occur in varied habitats. Ponderosa Pine-Gambel oak (Q. gambelii) and mixed-conifer forests, typically dominated by Douglas-fir and/or white fir (Abies concolor), are often used. In Arizona, ponderosa pine-Gambel oak vegetation was selected, and roosting Mexican Spotted Owls in New Mexico generally preferred mixed-conifer and mixed-conifer/oak forests. The majority of roosting sites in southern Arizona were in mixed-conifer or pine-oak habitats, but some occurred in Madrean evergreen woodland and interior chaparral. Pinyon-juniper (Pinus spp.-Juniperus spp.) woodlands provide nonbreeding habitat and may be used to some extent during the breeding season. However, in New Mexico, pinyon-juniper and open ponderosa pine woodlands were avoided. Other woodlands used by Mexican Spotted Owls include riparian woodland, encinal oak (Q. emoryi, Q. arizonica, Q. oblongifolia, Q. grisea) woodland, pine (Pinus leiophylla, P. engelmannii, P. ponderosa, P. strobiformis) woodland with evergreen oak (e.g. Q. chrysolepis) understories, and Arizona cypress (Cupressus arizonica) woodland. Montane meadows are used to some extent for foraging. Habitats such as mountain shrub and desert scrub are used during the winter by dispersing juveniles and possibly migratory adults.