Shorter winters and the decreasing extent of snow cover worldwide threaten the survival of animal species adapted to living in snow. An international research team has identified regions where species can successfully adapt to new climate conditions, partly by adaptive evolution. EOC’s “Global Snow Pack”, a remote sensing product documenting how snow cover is evolving worldwide, was used in this study.
There are 21 species of mammals and birds that change the colour of their coats or feathers from brown to white in winter, for example to conceal themselves from predators. In several regions, however, some of these species increasingly do not undergo this colour change — a phenomenon attributed to the effects of climate change on snow cover, among other causes.
Eight of these species were analysed in the study to determine the conditions under which a colour change did not occur. Besides the temperature, the duration of snow cover plays a decisive role. The probability of a colour change in winter drops as the number of snow-free days increases. If a species does not undergo a seasonal colour change, mortality drops when there is at the same time a reduction in the duration of snow cover. The study shows how evolution can help reduce the effects of climate change for individual species. If the animals are unable to quickly adapt to changed circumstances, then their survival in the affected regions is endangered.
“Global SnowPack”, developed by EOC and used in this study, shows at a resolution of 500 metres how the duration of snow cover has changed worldwide since 2000. Based on remote sensing data, it is available at EOC Geoservice (see Link). For the published study, population data for the relevant species were correlated with “Global SnowPack” and analysed statistically. This methodology supplied evidence for the relevance of snow cover duration for the observed changing state of affairs regarding coat colour.
This research took place under the supervision of Professor L. Scott Mills of the University of Montana and was published in February and March 2018 in the journal “Science”. The insights gained can in the future help to protect regions also as far as the evolutionary adaptability of the species living there is concerned.