birth colony, but typically leave at two years of age, becoming fully sexually mature the following year. References Further reading Thorington, R. W. Jr. and R. S. Hoffman. 2005. Family Sciuridae. pp. 754–818 in Mammal Species of the World a Taxonomic and Geographic Reference. D. E. Wilson and D. M. Reeder eds. Johns Hopkins University Press, Baltimore. Carling, M. "Marmota caligata (hoary marmot)." Animal Diversity Web, University of Michigan. 1999. External links Mammals described in 1829 Arctic land animals Mammals of Canada Mammals of the United States Marmots Endemic fauna of North America