Observations on the Biology of Sorex trowbridgei in the Sierra Nevada, California

Recent years have seen the publication of life history studies for several kinds of soricid shrews, and we now have some idea concerning some of the salient biological features of these animals. There is an abundance of species of shrews, sometimes several species living in one locality, and it is a reasonable assumption that their habits are different. Also, it is not unlikely that some geographically widespread species will differ within themselves ecologically as well as morphologically, such differences reflecting responses to variations in their environments. As natural history studies of shrews gradually become more extensive and detailed, it may be possible to discover discrete biological differences among the various kinds and also to learn to what degree the environment may alter the biology of any one kind. The data here are not extensive, but concern one species, Sorex trowbridgei, in the Sierra Nevada of California. In some respects,...