Limited information exists on small mammals in industrial forests of northern California, USA. Small mammals are integral components of forest ecosystems serving as prey, regulating invertebrates, dispersing seeds, and as indicators of habitat quality. My thesis focuses on patch-level and fine-scale habitat elements that influence small mammal communities in industrial forests of northern California. The primary silviculture regime is small-scale (<8 ha) clearcutting followed by site preparation that includes various combinations of chemical, mechanical, and fire treatments. I trapped 11 small mammal species during the summers of 2011-2013 and collected count data on a subset of those species. In Chapter 1, I analyzed small mammal populations in 4 forest types (recent clearcuts (3-5 years old), 10-20 year-old plantations, rotation-aged stands (60-80 years old), and Watercourse and Lake Protection Zones) commonly found in industrial forests. I used generalized linear mixed models (GLMM) to assess patch-level (~6.35 ha) relationships between small mammal counts and commonly found forest types, and downed wood volume. Land cover composition of areas surrounding trapping webs was more influential on small mammal counts than was the forest type that contained the trapping array. Downed wood volume was positively correlated to small mammal abundance. In Chapter 2, I examined small mammal counts in relation to fine-scale (64 m2) habitat elements surrounding trap locations. I used GLMMs and found that shrub and downed wood cover were positively correlated with the number of individual small mammals captured; this relationship held across multiple taxon and trap types. This study is one of the first to be conducted on the small mammal community in industrial forests of northern California. Results of this research provide insight on small mammal populations in industrial forests and can inform timber management practices.
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