Fossil Shrews (Insectivora: Soricidae) from the Late Pleistocene of Colorado

Abstract

Five species of shrews (Insectivora: Soricidae), Sorex cf. S. cinereus, Sorex cf. S. preblei, S. nanus, S. monticolus, and S. palustris are reported from Cement Creek and Haystack caves, Gunnison Co., Colorado. Deposits in Cement Creek Cave date from 43,330 B.P., prior to the peak Wisconsin glaciation (20,000 to 18,000 B.P.), to the late Holocene. This cave contains a higher diversity of shrews with all 5 species represented, especially S. monticolus which is most abundant. Haystack Cave has deposits that date primarily from 19,990 to 12,910 B.P. Two taxa of shrews were recovered from this site, including 1 that might represent an undescribed extinct species of Sorex. All other species identified from these caves, except Sorex cf. S. preblei, currently occur in the Upper Gunnison Basin and indicate that primarily a mixed sagebrush steppe and subalpine forest envi- ronment existed near these caves during the late Pleistocene.