Late Pleistocene Collared Lemming (Dicrostonyx torquatus) from Northeastern British Columbia

Charlie Lake Cave is a terminal Pleistocene/Holocene archaeological and paleontological site in northeastern British Columbia (Driver, 1988; Fladmark et al., 1988; Driver et al., 1996). Located in the Peace River District to the east of the Rocky Mountains (56°16'35"N, 120°56' 15"W), the major feature of the site is a deep gully in front of a cave formed in a low sandstone escarpment. The gully runs parallel to the hillside, and has been filled with sediments moving down the hill since 10,500 B.P., resulting in up to 4.5 m thick deposits. The site is well stratified, and there is a strong correlation of radiocarbon age and depth, suggesting stratigraphic integrity. The site contains vertebrate assemblages deposited by natural agencies and human hunters, and there is also a long sequence of archaeological components at the site . The importance of the site was demonstrated by Fladmark's excavations in 1983 (Fladmark et al., 1988). Further excavations at the site were undertaken in 1990-1991, and remains of collared lemming (Dicrostonyx torquatus) were recovered during the second series of excavations. The specimens are described and their significance evaluated. Article Summary by Jonathan C. Driver, May 2015 This short paper provides information on an unexpected and unusual find from the lower layers at the site. After the 1991 excavations were finished we began to work on identifying the animal bones that were recovered. Somewhat to our surprise we found a few specimens of the collared lemming, an animal that today only inhabits the high tundra of the arctic. This wasn’t out of line with other species that indicated a cold and/or open unforested landscape during the earliest period of occupation – bison, ground squirrels and hares – but as collared lemming had not been found before in British Columbia it warranted a paper to itself. The paper describes the specimens, noting that they were somewhat larger than modern lemmings, and then looks at the known distribution of lemmings at the end of the ice age. There are a number of specimens from fossil sites (mainly caves) well outside their modern distribution. This presumably suggests lemming populations were able to colonize cold, open landscapes around the expanding ice sheets, and had enough time to move south as the ice sheets expanded and in turn created new habitat that was suitable for lemmings. As the climate changed and as forests moved in, lemmings were unable to survive and their populations dwindled and soon became extinct in the Peace River region.