Genic homogeneity among temporal populations of the eastern chipmunk (Tamias striatus)

Abstract

A population of eastern chipmunks (Tamias striatus) was surveyed for allozyme variation over two distinct reproductive seasons each year during 1987 and 1988. Individuals were placed into resident, recruit, and disappearing individual categories for the allozyme analysis. The resident population declined by 43% during the period of the study. Individuals in the recruit and emigrant categories accounted for about 50% of the population each season and the number in each of these categories varied widely from season to season. No inbreeding, based on genotype frequencies, was observed within the resident population. No significant genic heterogeneity was observed among temporally separated populations of chipmunks in the resident, recruit, or disappearing individual categories. The high levels of additions and losses from the population and the complex age-structure of chipmunk populations were likely the major contributors to the lack of inbreeding and seasonal differentiation. These results are contrasted with the more widely studied microtine systems.