News » Bear Update

Bear Update:

19-year- old Sadie, again with 3 cubs

by

comment

Whistler Black Bear Project

The large adult black bear lying at the base of the second growth Douglas fir watches the two sub-adult bears approach. She’s alert but not alarmed. The sub-adult bears begin grazing the lush grass, clover, and horsetail alongside the now, mostly bear-proof electric fence of the Whistler landfill. Aware of the larger bear at the edge of the forest, they keep their distance.

The jittery action in the tree branches above catches their attention — three small black, chimp-like bodies wrestle amongst their elevated sanctuary in the crown of the small 50-year-old conifer tree. The adult mother of these three, four-month-old cubs rises, yawns, and glances up into the branches of protection. She walks down the bank and onto the green-up.

One young bear stops feeding and watches her, the other resumes feeding.

The mother takes a few snips of clover and takes a few paces further. The young bear watching bolts, loping quickly 200 metres back into the forest.

The second sub-adult grazing is walking away quickly but the mother edges him on and charges fully for 50 metres. With both bears gone she walks around and sniffs their feeding space and returns to the maternal tree.

Mother bears are alert and defensive to all bears and coyotes, especially adult males, over the next two months during the breeding period. Dominant adult males may attempt to kill cubs to force a mother into estrus. Despite hundreds of documented acts of aggression from males, this experienced mother has only lost one cub, in 1998.

Now in the 12 th year of research, she continues to be known as Sadie , the oldest and longest monitored female bear in the Whistler population. First identified in 1992 during a preliminary survey of then, a much smaller landfill site, Sadie has been monitored through the production of 18 cubs. In 1999, she began producing litters of three cubs, now, four consecutive times.

Now at 19 years, she is getting older (bears live 20-28 years) and represents a very important individual for research. The successful long-term monitoring of Sadie reveals the reproductive patterns of an adult female back bear in relation to the management of a large landfill within her home range. Her datasets open views to many analyses of her behavioral and reproductive ecology. It’s interesting that her large litter sizes began when the landfill had improved its operation of the electric fence.

Sadie shares the Whistler Interpretive Forest and Cheakamus River environs with two other dominant adult females. These are the largest adult females in the Whistler population. Their territories reaching lower elevations allows for longer berry feeding days (July-October) compared to ski area females restricted to higher elevations and lower berry feeding days (August-September).

The study of female bear behaviour and biology is vital to understanding their ecology of kinship relations, response to natural food shortages and/or temporal shifts in the berry crop, and human/development activity. Scientific papers will be submitted this fall to the ninth Western North American Black Bear Workshop in New Mexico for April 2006.

Below is Sadie’s chronology of cub production and survival during 14 years of monitoring. Since 1994, 12 adult females (minimum) have been monitored with equal effort, a feat that took huge mental and physical efforts under many trying circumstances.

1992 – 2 cubs

1993 – 2 yearlings

1994 – 2 cubs

1995 – 2 yearlings

1996 – 1 cub

1997 – 1 yearling

1998 – 1 cub – mated because cub killed by adult male

1999 – 3 cubs

2000 – 3 yearlings

2001 – 3 cubs

2002 – 3 yearlings

2003 – 3 cubs

2004 – 3 yearlings

2005 – 3 cubs

Thanks to everyone who has reported bear sightings for the May-June spring bear count. The count is up to 45 black bears. Bears can be reported to me at 604-902-1660 or e-mail: mallen_coastbear@direct.ca Thanks to Pique Newsmagazine for sponsorship of Bear Update columns.

Add a comment