Wind as a Factor in the Local Distribution of Small Mammals

Abstract

The purpose of this study was to investigate the effect of wind on the distribution of small mammals within a large field. The field was uniform in all gross environmental factors other than a gradient in the velocity of the prevailing winds produced by a large windbreak on one side of the field. Animals were trapped at three distances from the windbreak; one where there was a large degree of shelter from the wind, another where there was no sheltering influence, and the third intermediate to these. The trapping results showed a statistically significant difference in animal distribution in these three areas, with more animals being found in the area of greatest shelter. Subsnow maximum—minimum temperature measurements showed no marked differences among the three distances from the windbreak, so this was discarded as a possible factor causing the observed distribution. The occurrence of deeper litter and snow accumulation in the more sheltered area, together with the fact that this provides shelter from weather and predators, led to the conclusion that these accumulations were the primary factors responsible for the observed distribution of small mammals within the study area. Since these accumulations are secondary effects of wind, it is proposed that wind can be a major factor in the local distribution of small mammals.