Important Bird Areas

Mountain Mahogany Shrubland

South Dakota

This IBA encompasses the majority of Mountain Mahogany shrubland found in South Dakota, primarily in Boles, Roby, Redbird, and Buck Horn Canyons. The dry slopes that support Mountain Mahogany-Skunkbrush shrubs with an open Pondorosa Pine canopy are attractive to a variety of western bird species that are rare or absent in the rest of the state.
The IBA includes the following sections in their entirety:
T2S R1E sections 31 – 33
T3S R1E sections 3 - 10, 15 - 21, 27 - 29, 33 - 34
T4S, R1E section 3

Ornithological Summary

This area hosts most of the known breeding population of Virginia’s Warbler in the state; this population is separated from the next nearest breeding population by more than 200 km (Swanson et al. 2000). This habitat also supports other rare species that prefer dry shrubland-open pine habitats such as the western race of Blue-gray Gnatcatcher. The ‘white-winged’ race of the Dark-eyed Junco, endemic to the Black Hills, is a common breeder in this IBA.

Conservation Issues

Mountain Mahogany and other shrubs are stunted, pruned, and crushed by cattle and overgrazing is a serious threat. Pine Bark beetle infestations, and the resulting logging, could wipe out the Ponderosa Pine overstory favored by Virginia’s Warblers and other bird species for song posts and nesting.

Ownership

Most of the IBA is owned and managed by U. S. Forest Service, Hell Canyon district. A small portion of appropropriate habitat is privately-owned.

Habitat

The predominant habitat type is Mountain Mahogany-Skunkbrush shrubland with an open canopy of Ponderosa Pine. Stands of Rocky Mountain Juniper also occur in the lower, drier areas. Pure Ponderosa Pine stands are at higher elevations. Open flat areas support grassland. There are some vertical sandstone cliffs and rimrock along canyon walls.

Land Use

Forest Service land is managed for multiple use; the predominant use on this IBA is livestock grazing. The privately-owned areas are pasturelands; there are also a handful of houses in Redbird Canyon, and a couple of small ranches elsewhere. Recreational activities, which are not significant, include hunting, ATV riding, and birdwatching.