OUP user menu

Winter Survival Adaptations of the Short-Tailed Shrew (Blarina brevicauda) in an Appalachian Montane Forest

Joseph F. Merritt
DOI: http://dx.doi.org/10.2307/1381276 450-464 First published online: 8 August 1986

Abstract

The short-tailed shrew (Blarina brevicauda) is a very common small mammal in eastern deciduous forests of North America. Survivorship of this winter-active soricid during the winter is good. This study examined seasonal changes in body mass, resting metabolic rate (RMR), and non-shivering thermogenesis (NST) of live-trapped B. brevicauda as important adaptations which enhance over-winter survival. Body mass of shrews captured in April increased 39% over average body mass of September-captured shrews. RMR in January represented a 38% increase in metabolic rate relative to August, and NST increased by 54% in January as compared to August. Monthly RMR and NST values showed an inverse relationship to minimum environmental temperature of the capture site. A general “adaptive winter profile” for B. brevicauda incorporates many behavioral, physiological and anatomical adaptations including: utilization of elaborate nests, food hoarding, reliance on abundant, energy-rich prey, winter foraging confined to a stable thermal regime, reduced activity during periods of cold, and increased thermogenic capacity in winter due to NST with resultant hypertrophy of interscapular brown adipose tissue.

Log in through your institution