NESTING HABITS OF THE LOGGERHEAD SHRIKE IN SAGEBRUSH

The Loggerhead Shrike (Lanius ludovicianus) is a widely distributed me mber of Idaho's sagebrush (Artemesia tridentata) rangeland avifauna. D uring 1991-1993, we studied the breeding ecology and nesting locations of the species in this semi-arid habitat. Most loggerhead nests (65%) were constructed in sagebrush, although bitterbrush (Purshia tridenta ta) and greasewood (Sarcobatus vermiculatus) were also used frequently . Height of nest shrubs averaged 162 cm (range: 89-297 cm), and the me an height of nests was 79 cm (range: 33-160 cm). Nest variables we mea sured did not differentiate successful from unsuccessful nests. Signif icant differences, however, distinguished the three primary nest shrub s: sagebrush shrubs used for nesting tended to be smaller than bitterb rush or greasewood shrubs. Nonetheless, nest height was nearly identic al regardless of shrub species, and nest success was independent of ne st shrub. The low nesting heights for the loggerhead in this sagebrush -scrub habitat represent a notable departure from nesting heights in m any parts of the species range, although they may be typical for the s pecies where it occurs in the southwest. The preservation of Idaho's s agebrush rangelands will be important to the longterm survival of this species in the state.