Polar bear lecture, May 28, at Canadian Museum of Nature, presented by Brenda Saunders

3 • POSTED ON May 12, 2008
Polar bear lecture, May 28, at Canadian Museum of Nature, presented by Brenda Saunders
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Back by popular demand, Brenda Saunders returns to the Canadian Museum of Nature on May 28 to give her fascinating slide show on polar bears. Time: 7 p.m. Register now! Seating is limited. Call 613-566-4791. Address: 240 McLeod Street (corner of McLeod.

The future of the lord of the Arctic

Back by popular demand, Brenda Saunders returns to the Canadian Museum of Nature on Wednesday, May 28, 2008 to present her fascinating talk and slide show on the polar bear, its life and future. The lecture begins at 7:00 p.m. at 240 McLeod Street (corner of Metcalfe).

Saunders has worked as a marine mammal specialist in the Eastern Arctic for the past three summers with an Inuit-owned expedition company, educating eco-tourists about the ecology of the polar bear. She will share her many stunning photos of magnificent fjords, tidewater glaciers, vast tundra vistas and, of course, adorable polar bears.

Saunders completed her Master's thesis on the mating system of polar bears, based on tissue samples collected by the Nunavut government in two areas: M'Clintock Channel and the Gulf of Boothia in the central Canadian Arctic. By 2001, the polar bear population in M'Clintock Channel had been severely depleted from over-hunting. That year, the Government of Nunavut implemented a moratorium on polar bear hunting in that specific management unit. By contrast, the polar bear population in an adjacent area, the Gulf of Boothia, was healthy.

Under co-supervisors Drs. Peter Boag and Peter de Groot, Saunders and a lab team at Queen's University used the DNA from over 650 bears in these populations to study family relationships among the bears. They concluded, as predicted, that male polar bears in their sexual prime are normally the most prolific breeders. However, in M'Clintock Channel, the removal of the male bears in their prime gave way for younger bears to successfully mate and sire offspring. Surprisingly, the genetic results also indicated a cub adoption event, multiple paternity within litters and some male bears as young as age three were successfully fathering offspring. This compelling research was the basis of an article, Who's Your Daddy, which appeared in an issue of Canadian Geographic in 2005.

"It is important that we understand more about the biology of polar bears so management strategies and decisions are based on the best available information," says Saunders. Her findings may have implications for the management system, which regulates the harvest of polar bears for conservation, Inuit subsistence and sport-hunting purposes. It is currently based on a harvest ratio of two males for every one female polar bear but does not address the harvesting of bears in their reproductive prime. Traditional knowledge and science are used to manage the harvest of polar bears, an important cultural tradition for Inuit as well as an economic resource. The small number of permits issued for sport-hunting in healthy populations brings in several million dollars per year to remote Nunavut communities that may otherwise have few sources of income.

"The harvest addresses social, cultural and economic community needs;" explains Saunders. "However, it remains controversial because the long-term future of the bears is in jeopardy from climate change. Harvest management is incredibly complex because managers must find a balance between traditional knowledge, science and international pressure."

In her presentation, Saunders will share the life history of polar bears and her observations of the changing climate in the Arctic, where the extent of receding sea ice is shocking. Polar bears depend upon the sea ice as a platform for hunting seals. With a longer ice-free summer season, the bears have less time to feed and put on enough fat to successfully reproduce and survive through the year. In the warm summer months they are fasting, therefore a longer summer also means more time using up precious fat reserves.

In the summer of 2007, Saunders and a group of tourists were traveling by zodiac and came across an unusual polar bear lying on a chunk of ice. "The bear was extremely skinny, belly-up and frozen stiff," she says. "The visible wounds that caused its death most likely resulted from a desperate and unsuccessful attack upon a walrus." For safety reasons, she could not disembark from the zodiac, but noted from her vantage point on the water that the bear was neither a "sub-adult" nor an old bear – the two age groups when it would be more likely to be skinny. Its emaciated condition was disturbing, leading her to wonder about the role of changing environmental conditions in the Arctic and their impact on accessibility of prey.

Currently, there are about 17,000 polar bears in Canada. "We still have more to learn about the lifecycle of the polar bear and the relationships between populations," said Saunders. "Most importantly, we need to recognize that our current lifestyle choices in the South, such as the extensive use of fossil fuels, have a substantial impact on the Arctic. The changes in the character and extent of sea ice are clearly evident and these changes have serious consequences for the future of Arctic ecosystems and the polar bear."

Saunders's slideshow is part of a series of lectures in celebration of the International Polar Year. The IPY is the largest-ever international scientific research programme in the polar regions. Thousands of researchers from more than 60 nations around the globe are participating in the IPY, which continues until March 1, 2009.

The lecture fee is only $5 and is free for Canadian Museum of Nature members (one adult per membership; all others covered in the membership are entitled to a 20% discount). Seating is limited and registration is required by calling 613-566-4791.

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