Studies of morphological parameters affecting ungulate locomotion in snow

It is suggested that differential ability to use varied snow depths may play a role in resource partitioning and differential winter mortality may be related to sex and age class differences in ability to cope with snow.

Abstract

We deal with possible morphological adaption to varied snow conditions by four North American ungulate species. Chest heights and weight loads on track are key parameters in estimating capabilities of species, and of age and sex classes within species, to cope with snow. Methods believed suitable for measuring those parameters in replicable fashion are discussed. Comparative studies of bison (Bison bison), moose (Alces alces), wapiti (Cervus elaphus), and white-tailed deer (Odocoileus virginianus) are described. There are pronounced differences in both parameters between species and between some age and sex classes within species. Chest heights of the three cervids differed by a fixed interval suggesting that differential ability to use varied snow depths may play a role in resource partitioning. Differential winter mortality may be related to sex and age class differences in ability to cope with snow. Morphological differences relate to regional distributions by determining species suitability for survival in varying snow regimes.