Bear Update: Fall Foraging Strategies By Michael Allen Black Bear Researcher Black bear activity is beginning to surface again, resembling the traditional fall levels throughout Whistler Valley. For most of late August through mid-September reports of bear activity were lower than during the early summer, when the berry crop was delayed and daily bear sightings were common. Many people asked me if the bears had gone into their dens or if they had moved from the valley in search of more abundant berry patches. Black bears are typically shy, secretive forest animals that have adapted to living in close proximity to human habitation. They have learned to exploit both natural and unnatural foods that are available within human development. When berry crops are late and limited in abundance, bears expand their forays for food, giving up their circuitous (regular daily) travel patterns. Bears can also learn to be extremely patient and tolerant of human activity — they are probably around us more than we know. Don’t forget we have removed (destroyed and relocated) around 50 bears so far this year. This removal catches up the valley population and creates gaps in the population’s social structure. These gaps will fill gradually by outlying bears, especially younger animals seeking a territory or expanding their feeding areas. Many of the cubs born this year will begin to disperse and expand their movements through the valley next summer or in the fall of 1997 as 1 1/2-year-old yearlings. There is also the percentage of bears which will return from having been relocated from 1994 through 1996. The distribution of bears in the Whistler area during the fall (September to early November) is guided by elevation (metres above sea level "ASL"). Elevation dominates the factors which regulate the abundance of ripe berries. Between 530 and 800 metres ASL, or from the Cheakamus River near the landfill up to ski trails just above Base II on Blackcomb, provided bears with the first ripe summer berries around mid-late July. Black huckleberry (Vaccinium membranaceum), the sweetest and most widespread berry in the valley, feeds bears until late August, when many berries begin to deplete (dry out). Bears occupying the valley bottom may move upslope in search of black huckleberries and other huckleberries as ripening continues later and higher in elevation. Bears can also remain in the valley and begin feeding on the white red-osier dogwood (Corns stolonifera) berries and red huckleberries (Vaccinium parvifolium). These are the most widespread ripe berries in September and October along the valley. These berries can sustain bears until they enter their dens in late October and November. Scattered locations of the orange Sitka mountain-ash (Sitka sitchensis) berries, the red highbush cranberries (Viburnum edule), and the depleting oval-leafed blueberries (Vaccinium ovalifolium) from summer, also provide continued feeding for bears in the valley. Resident bears (especially territorial mothers with cubs) of Blackcomb or Whistler and of other mid-mountain habitats at 900 to 1,500 meters ASL will follow the ripening of berries along the elevational gradient (uphill) throughout fall. These bears have grazed longer on grasses and clover on the ski trails before berries ripened at these elevations in late summer. Bear families do not often venture into the valley habitats because of competition from other bears and the added vulnerability of their cubs to people. Ripe berry productivity and abundance is down this year from last year’s excellent crops, due to the cold, cloudy spring. Productive berry patches are left scattered up and down the mountain slopes. Berries other than huckleberries are almost at normal production through the valley so we can expect a consistent bear-active fall. Early freezing temperatures in the sub-alpine (1,700 metres ASL) have left many huckleberry shrubs failed with only scattered ripe patches. However, one of the most productive berry crop areas on Blackcomb is in the newly-constructed gladed ski trails. They are a result of selective logging, where trees and snags are left in clumps so that sunlight can reach the understory, enhancing plant and wildlife biodiversity. The Bear Update columns are nearing an end, along with the bear’s active season. The next column will describe the trends of the Whistler black bear population. The remaining columns will reveal denning and winter sleep characteristics. Remember the best way to cope with our neighbours is to exercise the GARBAGE, EDUCATION, and TOLERATION approach to bear management. Be aware of bears in all seasons and dispose of your garbage securely. Learn from bear interactions and educate yourself about bear behaviour — practice prevention. Tolerate the presence of bears at a safe distance and practise observing bears. Learning how bears react to our presence will undoubtedly aid us in interpreting their behaviour and our behaviour around them. Michael Allen can by heard on Mountain FM’s Mountain Monitor program the fourth Tuesday of each month. Listen Oct. 28 at noon.
