Song post and foraging site characteristics of breeding Varied Thrushes innorthwestern California

We used a hierarchical approach to describe habitat characteristics of song posts and foraging sites used by Varied Thrushes (Ixoreus naevius) in coas tal redwood (Sequoia sempervirens) forests of northwestern California, We m easured mesohabitat (0.04-ha circular plots) and microhabitat (0.5-m radius ) scale attributes centered on occupied and random song posts and foraging locations at four study sites during March-August of 1994 and 1995. Ninety- live percent of song posts were in trees or snags. Male thrushes used song posts with low foliage density near the top of large conifers (microhabitat scale), located on steeper slopes, surrounded by a high density of trees, and centered in drainages closer to water (mesohabitat scale) as compared t o random locations. Varied Thrushes foraged predominantly on the ground ear ly in the breeding season, then subsequently included fruit in their diet a fter the young had fledged. Although many variables were correlated with gr ound foraging locations, microhabitat foliage density had the greatest expl anatory power, indicating thrushes: selected foraging locations primarily a t the microhabitat scale, and emphasizing the importance of measuring habit at characteristics at the appropriate spatial scale. Abrupt forest edges, s uch as those produced by clearcuts, may reduce habitat suitability for Vari ed Thrushes possibly explaining their absence from small forest fragments d uring the breeding season.