Data from: Atypical winter coat coloration of snowshoe hares near the southern extent of their range

Many species have a variety of adaptations to winter weather, but these
adaptations could become maladaptive if winter snowfall and temperatures
are more variable. Snowshoe hares (Lepus americanus) molt from a brown
summer coat to a white winter coat, but reductions in snow cover could
result in phenotypic mismatch, which in turn could reduce survival. Hare
populations near the southern extent of their range might be especially
sensitive to phenotypic mismatch because of variable winter weather, but
variation in winter coat coloration could allow for these populations to
persist in inconsistent snow cover conditions. Using capture data (n=59
individual hares) spanning 8 years, we document the prevalence of 3
atypical winter coat color phenotypes (brown bodies, brown-ringed eyes,
and brown ears) in a snowshoe hare population in Pennsylvania. The
majority of hares in our study (84.7%) exhibited at least one of these
atypical winter phenotypes, with a high probability of hares having
brown-ringed eyes or brown ears, and four hares remaining brown during the
winter. The presence and high prevalence of non-white winter phenotypes
could be beneficial for hares in this population if winters are mild with
low snow cover. If these phenotypes have a genetic basis, there may be the
evolutionary potential for hares to persist near the southern extent of
their range, even in the face of changing winters.