Effects of timber harvest on small mammal captures in experimental forestry plots

Abstract

To investigate effects of timber harvest on small mammals, we compared capture rates in experimental forestry arrays of uncut forest, partial cut forest, and clearcuts with high and low coarse downed wood in Missouri, USA. Past studies show that effects of timber harvest on small mammals depend on species and forest type. We used an information theoretic approach to compare the effects of timber harvest treatment and habitat characteristics on capture rates. Sorex longirostris captures were best predicted by timber harvest treatment. S. longirostris had higher captures in the clearcut with low downed wood, intermediate numbers of captures in the partial cut and clearcut with high downed wood, and low captures in uncut forest. However, despite differences in captures between the clearcuts with high and low downed wood, we found no difference in habitat variables between the two clearcut types. Blarina spp., Microtus pinetorum, and Peromyscus spp. captures were best predicted by habitat variables rather than timber harvest treatment. Blarina spp. captures were associated with lower leaf litter depth. Peromyscus spp. and M. pinetorum captures were associated with increased coarse downed wood, possibly due to their preference for nest building under logs. Some of these relationships differ from results in other areas of the United States, which may reflect differences in species-habitat relationships in different forest types or regions. Relationships between species and habitat variables will be useful in adjusting forestry practices to meet species management objectives.