t
SCIenCe
Bears in a changing climate
I
n the 21st century, bears
mostly populate North
America's more northerly
regions, although less than 200
years ago they roamed more
widely. While populations of
black bears still call northern
Mexico and the continent's
eastern region (except for
Prince Edward Island) home,
the grizzlies are gone, due to
habitat loss. Now, like the rest
of us, they'll have to deal with
climate change too.
A resilient species, bears
adapt to warm or cold habitats
as well as menu changes. They'll
gobble almost anything and
they may weather climate
change better than humans,
unless their food becomes
scarce. Whitebark pine seeds,
for example, are a vital food at
high elevations where grizzlies
roam. An introduced fungal
disease is ravaging the trees,
with warmer temperatures
potentially dealing fatal blows
of increased pine beetle
infestations and the invasion of
other tree species in historically
marginal habitat.
•
An adult female grizzly
breaks from foraging in
the Khutzeymateen Grizzly
Bear Sanctuary to gaze at
the day's first sunbeams.
photo: Brad Hill
30
B rIT IS H C olUMBIA MAgAZI NE • FAll 2013
