Skip to content
Join our Newsletter
Join our Newsletter

Bear Update: Yearling bears Part II

Profiles of moms’ personalities

Whistler Black Bear Project

A large focus of my research during the past 11 years has been on female black bear behaviour and biology and how kinship relations develop within Whistler’s dynamic four-season resort. The resort’s continually changing environment sets the stage for mother bears to formulate situation-specific strategies for raising cubs and yearlings. Moms’ experiences – trials, errors, and rewards – remembered and rationalized through time, builds the lesson plan for their offspring.

The environment we create (through industrial, recreational, and residential developments) for a mother bear is enhanced with an over-abundance of foods (green-up, insects, and berries) but also human foods, and equally paired with the multiplication of bears. Bear density can be high and bear survival very competitive.

Adult females stress in coping with the close proximity of male bears (and coyotes) and may strategize feeding locations within residential or recreational environs to avoid larger dominant animals. Each mother is unique in developing strategies to forage the seasonally required foods for her young and in meeting sufficient weight gain requirements for her own pregnancy.

The diverse experiences of adult female black bears produces an equally diverse set of yearling personalities. After 17-19 months of maternal care, cubs (now called yearlings) are pushed away from their mothers and security. Mothers allow daughters to remain in their natal range until maturity (4-5 years old) while sons are subsequently forced from their mother’s territory to avoid inbreeding and reduce future male-induced aggression toward cubs. Living a life of vulnerability and risk, yearling bears (25-35 kg in the spring) proceed on the only course which keeps them alive in an environment challenged by the hurdles of human development and competing bears.

I have delineated four types of maternal behaviour that set the stage for learning during the course of cub-hood to sub-adult-hood ( < 3 years old). All 23 female bears reside within the 165-km 2 Resort Municipality of Whistler. From 96 cubs, 83 per cent (80 yearlings) have survived to post-family break-up. This maternal behavioural typing will help determine the progressive stages of sub-adult bear behaviour for the Whistler Bear-ID Index. The index provides a basis for population inventory and individual identification based on physical (photographic), genetic (DNA fingerprinting), and behavioural (personality influenced from mother and human-modification). The outer perimeter of Whistler Valley is defined as environs above 725 meters elevation.

Type I

Type I yearlings are those cubs which have been raised by mothers living outside of Whistler valley and do not have access to human food but forage enhanced, natural foods in the presence of distant ( > 50 metres), daily human activity within recreational-modified environs (ski area and/or hiking/biking trails). Mothers are usually disturbed by people within 15 minutes and will retreat if approached < 30 metres by 1-2 people.

Type II

Type II yearlings are those cubs which have been raised by mothers within the outer perimeter of Whistler valley and are human-habituated at closer distances (< 50-metres). These mothers occupy recreational activity areas (higher use mountain bike and/or hiking trails) and may not retreat from human approach to 10-20 metres. Mothers will feed for > 30 minutes in the close presence of < 30 people.

Type III

Type III yearlings are those cubs that have been raised by mothers who reside near accessible human food such as the Whistler landfill, residential areas, and campgrounds. These mothers have a history of consuming human foods as seasonal supplements within close proximity to people (< 30-metres) and are tolerant of people for > 60 minutes.

Type IV

Type IV yearlings are those cubs that have been raised by mothers occupying urbanized bear habitats within Whistler valley (Lost Lake Park, Emerald Forest, etc.). These mothers live at the greatest risk because of their close, daily proximity to humans. They are susceptible to injury and death from vehicles and trains and human—caused mortality from conflicts with human-food attractants. These bears may be tolerant of people to 3-metres and boldly investigate decks, porches, and partially opened windows and doors. Mothers and related offspring will boldly reside in human inhabited areas.

These behavioural designations are guidelines for formulating progressive profiles of yearling and sub-adult (2-3 year olds) black bears in Whistler Valley.

Monitoring Bear Families, Yearlings, and Large Males

If interested, please report (for research and monitoring) mothers with cubs, yearlings (35-45 kg in summer/fall), and large adult bears. I have been developing profiles of mother-offspring relationships and how mothers are transmitting information to offspring during their first and second years. Sightings of yearling and large adult bears are also critical because they represent opposite ends of bear behaviour and role-playing in the population. Thanks to all contributors. The results of the Spring Bear Count will be published in the next Bear Update column.

Questions or information on bears please call me at 604-902-1660 or e-mail

Thanks to Pique Newsmagazine for sponsorship of Bear Update columns.