The Archaeology and Paleoecology of Alpine Ice Patches: A Global Perspective
Dates
Year
2012
Citation
Andrews, Thomas D., and MacKay, Glen, 2012, The Archaeology and Paleoecology of Alpine Ice Patches: A Global Perspective: Arctic, v. 65, no. 5, p. III-III,IV,V,VI.
Summary
What do climate change impacts to ice patches mean for the caribou that use them? Research in both Scandinavia ([Anderson, J.R.] and Nilssen, 1998) and Canada (Ion and Kershaw, 1989) demonstrates that reindeer and caribou use alpine ice patches to cool down on warm summer days and to seek relief from parasitic flies. Indeed, it is this behavior that led ancient hunters to ice patches in the first place. In 2010, during summer fieldwork in the Selwyn Mountains, we witnessed mountain caribou bedding down in dung where ice patches had existed until recently, suggesting that caribou are habituated not only to ice patches, but also to their specific locations, whether ice remains or not. As these summer alpine patches continue to melt and [...]
Summary
What do climate change impacts to ice patches mean for the caribou that use them? Research in both Scandinavia ([Anderson, J.R.] and Nilssen, 1998) and Canada (Ion and Kershaw, 1989) demonstrates that reindeer and caribou use alpine ice patches to cool down on warm summer days and to seek relief from parasitic flies. Indeed, it is this behavior that led ancient hunters to ice patches in the first place. In 2010, during summer fieldwork in the Selwyn Mountains, we witnessed mountain caribou bedding down in dung where ice patches had existed until recently, suggesting that caribou are habituated not only to ice patches, but also to their specific locations, whether ice remains or not. As these summer alpine patches continue to melt and disappear, what long-term impacts might this have on northern mountain caribou or wild reindeer populations? Importantly, how might changes in mountain caribou populations affect the Aboriginal societies that hunt them? Caribou population changes in Canada have been dramatic in recent years (Festa-Bianchet et al., 2011), and blame is attributed to a complex set of stressors, only some of which can be linked to climate change. Human land-use changes, habitat fragmentation, lack of aggressive management actions, and in some cases, catastrophic events, such as the avalanche that killed the last five mountain caribou in BanffNational Park in April 2009 (Hebblewhite et al., 2010), have all led to declining caribou populations. However, climate-induced habitat changes may also affect caribou energetic costs, resulting in changes to vital rates (e.g., birth, death, and fertility). As the papers in this volume demonstrate, alpine ice patches can provide important baseline data on caribou population genetics and health that can be applied in future research and management. Further research is urgently required to understand ecological change and the resulting impact on heritage resources associated with these significant habitats. The next three papers explore the physical and ecological dimensions of alpine ice patches in the Selwyn Mountains. Meulendyk et al. use ground-penetrating radar and ice coring to determine the internal structure of two ice patches. They develop a model of ice patch formation and discuss potential for the use of ice patches to reconstruct regional paleoenvironmental conditions. The fact that ice patches are perennially frozen and are relatively static features (i.e., compared to glaciers) accounts for their ability to preserve even the most fragile components of ancient hunting weapons. [Jennifer Galloway] et al. evaluate the use of caribou dung preserved in alpine ice patches to reconstruct paleoecological conditions in alpine environments. Their analysis of pollen and spores trapped in caribou dung indicates that vegetation communities in the vicinity of the ice patches have remained largely unchanged for the last 5000 years. In a similar manner, plant fragments document the stability of summer caribou diet over this timeframe. Letts et al. use ancient DNA techniques to investigate the population dynamics of caribou in the Selwyn and Mackenzie Mountains. Comparing mitochondrial DNA sequences from ancient bones, teeth, and antlers preserved in alpine ice patches with those of modern caribou, they show that the resident Redstone population of mountain caribou has been "robust to environmental change over the past 4000 years" (p. 92). Taken together, Galloway et al. and Letts et al. provide an important baseline for evaluating changes to mountain caribou diet and health that could occur as the global climate continues to warm.
