Skip to content
Join our Newsletter

Bear Update: Dry fall boosts valley bear activity

Black Bear Researcher Draught conditions that stretched from early August through early November, followed by a mild, wet mid-November, influences local bear biology in four ways: 1) reduces fall weight gain by yielding smaller size (berries) and abu

Black Bear Researcher

Draught conditions that stretched from early August through early November, followed by a mild, wet mid-November, influences local bear biology in four ways: 1) reduces fall weight gain by yielding smaller size (berries) and abundance of huckleberries, 2) reduces survival rate by forcing bears to search for food closer to people, increasing human-bear conflicts, 3) reinforces human food feeding behaviours, increasing bear’s knowledge of potential human food locations to return during natural food shortages, and 4) prolongs den entrance, increasing potential conflicts with people as well as stress and weight loss during movement to den through snow.

Influences of temperature and precipitation play a major role in bear biology. Below are seasonal descriptions of bear activity from changes in weather.

July-August Berry Ripening — Dry and Hot

When valley bears are feeding on ripening huckleberries in early July, ski area bears continue grazing on grasses and clover waiting the ripening of higher elevation berries. The late, cooler spring gave way to late summer during July when sunshine and higher temperatures gave a boost to the struggling berry crop. But, Mother Nature pushed the limit and extended her influence into a bone-dry August. Prolonged draughts reduce berry size and began drying up valley berries earlier than normal.

For ski area bears, smaller berry size increases the time it takes for bears to find and consume berries. Bears also have to consume more berries because of the smaller contribution of pulp/juiciness per berry. Concentrations of berries in dense patches during late August will keep bears feeding in small areas. This August bears were rotating through numerous shrub fields due to a wide dispersal of berries. For bear families, this feeding strategy can be harmful in that cubs will be exposed to more threats (other bears).

September Berry Feeding — Dry and Warm

The peak berry feeding period for ski area bears is September, and for valley bears August and September. Valley bears typically have a longer berry feeding season than ski area bears.

This year in the ski area, berries began shrivelling during early September. Because of their small size the berries tend to dry out faster. Berry feeding was concentrated for a short period (late August to mid-September) in large shrub fields (i.e., Greenacres, Raven ski trails). From mid-September on bears began to disperse, feeding throughout shrub fields inside and outside of the ski area boundary.

Reduced berry crop in the fall yields the greatest impact on mothers with COY (cubs-of-the-year/January birth) and sub-adult bears. These bear class are generally restricted to smaller movements due to burdens of cub rearing and inexperience, respectively. Adult males that do not have the role of cub rearing may travel extensively to search for alternative food sources during natural food shortages. Yearling to 2-year-old sub-adult bears do not have the experience and dominance to search wide ranging areas and fear of conflicting with larger, dominant bears or bear families. As a result they tend to move near people and garbage sources.

October Berry Drop — Dry and Warm

Huckleberry depleted during late September. Bears took advantage of Sitka-Mountain Ash berries through mid-September to mid-October. A few early snowfalls occurred in early October but had little influence. However, overnight freezing dropped what few shrivelled "weak" berries remained. In comparison, last year’s huckleberry crop allowed bears to feed through mid-October snowfall.

Post-berry season, ski area bears will revert back to grass/clover grazing along ski trails, typically boosted by rainfall. This October rainfall was absent and ski trails did not yield lush patches of green-up, so even many ski area bears had to begin their risky temptations in the valley. By mid-October there was a very low supply of natural bear food worthy of natural foraging. Bears began to look toward valley sources of human food as supplements.

November Garbage Feeding — Warm and Wet

After the draught, mild weather through early November is allowing bears to remain active and search out alternative food sources at garbage containment sites throughout Whistler. Typically, a bear will sleep most daylight hours and feed at a dumpster, compactor, re-cycling depot, or residential area during nocturnal hours, when human activity is low to non-existent. Bears have been exercising this behaviour for the last 40 years in Whistler.

The knowledge, strategy, and ultimate rewards of human food are part of a process which resident and transient bears experience every year, to some degree. There are major differences between the types of bears that use human food. All consumption of human food by bears is bad. Many resident bears, especially sows with cubs, use human food as a supplement for weight gain during periods of natural food shortages, such as this fall’s poor berry crop. These resident females do not consume human food all year except for two weeks before denning.

November Denning — Warm and Wet

Typically, winter snowfalls during November force bears into denning areas after successful berry feeding and weight gain during August through October. This year, because poor berry crops resulted in underweight bears and warm, wetter weather allowed bears to remain active looking for alternative food sources near people, expect bear activity to continue through November, especially during nocturnal periods. Increasing snowfalls at higher elevations and gradual lowering of the freezing level during mid-late November should begin to push bears back into denning areas. The bear that is active in your backyard may travel 5-50 km to reach a den it selected in September.

Better Attitudes

During the last nine years in Whistler people have witnessed re-occurring natural fall bear food shortages (poor berry crops) with the responding increase in bear activity near people. How people respond to this "backyard" bear activity has changed significantly. From the mid-1990s, when frantic phone calls about aggressive, garbage bears flooded the Conservation Officer Service’s office, to the inquisitive last few years when people developed a serious interest in local bears, people’s attitudes are changing for the better. Whistler residents and visitors are growing more tolerant of ursine neighbours.

This year hundreds of people have called the Whistler Black Bear Project with questions and sightings regarding local black bears. I would like to thank everyone for their input. Public involvement and communication on bear behaviour, biology, and ecology is vital to successful bear-people management. People need to know and understand what is going on with bears, why the bears do what they do, and how people, residents in bear habitat, can accommodate the close activities of black bears.

Early winter (Nov-Dec) Bear Sightings

I am interested in bear activity people may experience throughout the Sea to Sky Corridor during November, December, and January. Information is useful for the denning period database which records trends in bear activity relative to fall food abundance and local weather patterns. All information is used for scientific record only. Please note the date, time of day, and possible individual characteristics (body size, colour, chest markings, ear tags, presence of cubs, or behaviour). Report sightings or address questions to the Whistler Black Bear Project at 604-902-1660 (Whistler) and 604-898-2713 (Squamish) or e-mail mallen_coastbear@direct.ca

Thanks to Pique Newsmagazine for sponsorship of Bear Update columns.