Population ecology of sciurids in northwestern Minnesota.

Abstract

A 22-yr study of population dynamics for Spermophilus tridecemlineatus, S. franklinii, Tamias striatus, Eutamias minimus and Tamiasciurus hudsonicus was conducted. Changes in density may be cyclic. S. franklinii provided the strongest case for periodicity, but causal mechanisms are unclear. S. franklinii may be involved in the snowshoe hare Lepus americanus - vegetation hypothesis. Life tables and survivorship curves suggest age-independent survival among middle age classes with higher mortality for juveniles and old individuals.-from Authors