PATTERNS OF INITIAL SMALL MAMMAL COMMUNITY CHANGE AFTER CLEARCUTTING OF TEMPERATE NORTH-AMERICAN FORESTS

A review of 21 published studies revealed a general pattern of positive initial responses of small mammals to conventional clearcutting of temperate North American forests. Four measures of small mammal abundance and diversity exhibited significant patterns of increase: overall relative abundance of small mammals, and abundances of microtine rodents, Clethrionomys gapperi, and Peromyscus spp. in confierous forests. There were non-significant patterns of increase in seven other measures: species richness, diversity (Shannon index), population density, and abundances of soricids, sciurids, zapodids, and Peromyscus. Community evenness, and abundances of Tamias (Eutamias) and Peromyscus in deciduous forests decreased in a majority of studies. 'In general, responses of small mammals to clearcutting were similar in deciduous and coniferous forests. The principal exception involved the abundance of Peromyscus, which evinced a significant pattern of increase in coniferous forests but tended to decline in abundance following clearcutting of deciduous forests. The potential influences of forest type, population levels of small mammals, single-sample surveys, and site characteristics to variation in patterns of community response are examined, along with the potential impact of whole-tree harvesting on the responses of small mammals to clearcutting.