Page 11 - Gateways_2017_Fall

GRIZZLY
BEAR

WELFARE

Catnapping
Bears

Many people assume that our grizzly bears, Axhi and Jim, hibernate
every winter. But in truth, they have never hibernated. Instead, Axhi
and Jim enter torpor, which, simply put, is a truncated daily version
of the more seasonal hibernation. An animal in torpor drops its body
temperature and slows down its metabolism for a short period of
time. Since air temperature determines torpor, an animal in this state
can wake any time the weather is warm. Unlike in hibernation, it
doesn’t wait for spring to forage for food.
The animal care specialists at GREAT BEAR WILDERNESS ensure that our
bear brothers can enjoy their torpor naps, mimicking the routine
of grizzlies living in the wild for their mental and physical health.
In mid-September, the specialists begin gradually decreasing the
grizzlies’ caloric intake from 13,000 calories daily. By mid-December,
the bears receive 2,000 calories a day and continue that intake until
early spring.
By late November, animal care staff have stopped offering the
bears training opportunities and enrichment items to manipulate.
They add bales of hay, combined with wood wool, for the bears to
use to build winter nests inside a special den in the exhibit. (Guests
have a clear view into the den.) After Holiday Magic, our team places
pieces of the temporary trees that adorned the zoo for the season in
the den to block the wind.
Jim, the more dominant brother, gets first choice of denning
material and location. He snoozes in the back of the den, typically
out of the view of guests. Axhi doesn’t get the prime location,
but staff regularly add additional bedding for him, and he makes
multiple nests, creeping ever closer to his brother.
By the beginning of January, the bears tend to spend up to 23
hours a day sleeping. They mostly huddle in their den, but on
warm days, they can head to their open-air yard. The choice is theirs
because their 2,000-calorie diet converts into enough body fat to
support them in any temperature.
Each day, staff open the door of an indoor habitat to allow the
bears to come inside and eat. Since the food is placed near special
bear-hardy scales, it’s a good opportunity to monitor the animals’
weight and ensure they stay within a healthy range for their age.
As the weather gets warmer, staff remove the bedding and
increase the bears’ caloric intake. By the time spring rolls around, the
two are ready to enjoy the weather and take a dip in their pool.
Providing denning conditions not only is naturalistic for these
animals but also gives us the chance to educate our guests about
this aspect of grizzly bears’ lives. █
BROOKFIELD ZOO | FALL 2017 11