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Bear Update

Moms and – finally – peak berries



Bear Researcher

The large female black bear drops heavily onto her front left leg, the paw skidding along a slick, rain-soaked log. A sharp pain stabs her left shoulder but she shakes it off and slumps into a dense clump of berries between two old growth cedar stumps. Her large triangular-shaped head dives into the canopy of elliptical foliage. Colour perception is high and she immediately targets blue and shiny purplish-black berries. She nibbles the berries quickly, detaching them from their single stems. Her 18-year old eyes work ahead of her mouth, almost bird-dogging the next location of disaccharide sugars. The accumulations of these 8-mm diametre juicy fruits are the foundation to successful hibernation and gestation.

Vaccinium (huckleberry and blueberry) are now at their peak above mid-mountain elevations (>1,400-metres) surrounding Whistler. Early September’s sunny, dry days saved approximately 60 per cent of the otherwise, 2-4 week late summer-fall berry crop. Up to 20 per cent of the crop has succumbed to mould, rot, and shrinking — a sign of too much rain during the summer (July-August) swell stage of the berry.

The female straddles over the next clump of 130-cm tall shrubs. Like a fork, the angled prongs of berry stems stick up around her 94-cm shoulder height. Her head methodically surveys the angled micro-forest. Within seconds eight berries are nibbled away using loose, flappy lips. She orients right, slurping 11 more berries then backward around the patch consuming six more.

Berries are swallowed whole — chewing only wastes time.

She pivots to the left and takes in 16 more berries. Her pivot reveals a limp which only slows her momentarily — a knee-jerk reaction from an old fracture, healed during hibernation four winters ago. Berry consumption for this female is rewarded on a small scale, but only she knows the persistence needed to accumulate time and gross volume of berry intake.

Her fight is with her body’s biological clock. Four weeks ago, in mid-August, 1-3 eggs (usually) stalled at the blastocyst stage following fertilization and refused to implant until late November and the outcome of her pre-denning weight. Now Marisa, the oldest resident mother on Blackcomb Mountain, maximizes daily foraging effort all daylight hours to gain as much weight as possible before the onset of snowfall at higher elevations, signaling the end of the berry crop.

In early December, X number of eggs will implant, depending on her weight gain, and cubs will be born from mid-January to mid-February after only 40-60 days of fetal development. If females do not gain sufficient weight, few to no cubs are born.