New paper: hares, snow and camouflage

Mountain hares in Scotland show increasing camouflage mismatch due to less snowy winters.

Mountain hares are one of 21 species that molt from a dark coat in summer to a white coat in winter to maintain camouflage against snowy landscapes. But due to climate change, the duration of snow cover is decreasing – creating a “mismatch” in seasonal camouflage that exposes the hares to predators.

Marketa Zimova, an evolutionary ecologist at University of Michigan’s Institute for Global Change Biology, lead author of the new study, explains that the observed lack of change in the timing of important life events, or “phenological shift”—an organism’s ability to adapt the timing of their life events such as molts to changing environmental conditions, can endanger a species’ survival.

Paper (if you don’t have institutional access, try sci-hub):

Lack of phenological shift leads to increased camouflage mismatch in mountain hares, Zimova et al, https://doi.org/10.1098/rspb.2020.1786

I helped support this work through the snow data collation and modelling I did during my PhD (50 MB pdf). I mapped my snow modelling results to the hare survey locations and produced estimates of snow cover duration each winter. I also used R to find the nearest metrological stations adjacent to each hare survey site and apply a lapse rate to adjust the station temperature to the survey site. You can view the code to do this here:

Michael Spencer, & Marketa Zimova. (2020). Temperature series for 9 Scottish mountain sites, including generation code [Data set]. Zenodo. http://doi.org/10.5281/zenodo.3948568.