Description and Ecology: Colorado's geologic history lends itself to creation of cliff/rock habitats for birds. Formation of the Rocky Mountains by uplift and volcanism, followed by erosion by glacial and other forces, led to the development of a landscape with high topographic relief. On the Colorado Plateau (included in Physiographic Area 87), erosion sculpted a landscape of bluffs, cliffs, plateaus, and canyons. The stability and persistence of cliff/rock formations encourages the repeated use of specific areas as breeding habitat by birds, use which frequently extends well beyond the lifetimes of individual birds. Unlike other habitat types that are vulnerable to direct manipulation by humans, cliff/rock habitats are relatively unchangeable, although their value to birds can be degraded.

Importance and Conservation Status: Birds that use cliffs for nesting are more susceptible to loss of nesting habitat than many other species because they rely completely on cliffs as nest sites and because the number of suitable nest sites is finite and essentially non-renewable. For some species, all suitable nest sites may be occupied in some areas, making it impossible for the local population to increase.

Conflicts related to nesting birds that use cliffs, rocky ledges, and small rocky outcrops include rock climbing, mining, housing development, and construction of roads, hiking, bicycling, and horseback riding trails. Probably the greatest disturbance factor in cliff/rock habitats is rock climbing. Mining and construction can have negative impacts when they occur at the base or the top of cliffs, rocky ledges, or small rocky outcrops.

Cliff/rock habitat can be protected by making land managers and the general public more aware of the importance of this habitat type and by controlling the use and development of these habitats wherever necessary and possible. Establishing buffer zones, temporary closures, and in some cases designation of special areas (Research Natural Areas, Areas of Critical Environmental Concern, Special Management areas, or sanctuaries) can provide essential protection. These protective designations can include significant surrounding habitat such as primary foraging areas, where there may be additional impacts to consider.

Priority Species Accounts: Two species are identified as high priority in cliff/rock habitats in Physiographic Area 87: Peregrine Falcon and White-throated Swift.