POLAR BEAR TRACKING
Polar bears are just one of many drawcards of the Arctic but are easily the most eagerly sought experience for those travelling to the area. It is an intense moment when the call ‘polar bear!’ goes out from the deck, and our ship crew report they have never seen passengers move as fast as when they hear a bear has been spotted!
We have recently teamed up with a group of researchers from Alberta University, Canada as they work to understand the effects of climate change on the sea ice habitat of polar bears in the Foxe Basin in Nunavut Territory, Canada.
The team have fitted six female, adult bears with radio collars which send, via satellite, updates on the bears’ position every four days. Regular trips to the area with tracking equipment provide new information on their condition.
How it’s done
The bears are immobilised with a dart gun shot from a helicopter, measurements and sample are taken and the collar attached. Radio collars can only be attached to female polar bears as male bears have necks that are wider than their head so the collars simply fall off. |
Why track?
Following polar bears in their environment gives us a picture of how they are living in their habitat and means we can develop an understanding of how changes to their environment, in particular a warming climate, will affect them. Awe-inspiring they may be, but like all polar creatures their future will be impacted by issues created by global warming. Large carnivores like polar bears are particularly sensitive indicators of ecosystem health, and if they become unhealthy it is often a sign of something wrong in the wider Arctic marine system.
Polar bears only come ashore when sea ice habitat is unavailable, from June/July to October/November in the Canadian Arctic, and while ashore, enter a fasting state.
Analysis of sea ice in Foxe Basin and Hudson Bay shows reduced sea ice coverage and changes in freeze-up and ice-free dates. These changes mean the ice melts earlier and forms later and the bears are left with less time to hunt for food, hindering their ability to successfully reproduce. Feeding during these months is vital for them to build up enough body fat to cope with the months spent fasting on land during the summer.
OUR 6 ‘STARS’
Polar bear #34046 was captured along the coast of northwest Roes Welcome Sound, near Repulse Bay. Her weight was 267 kilograms and she was accompanied by a large (78 kilogram) male cub of the year.
Polar bear #34049 was captured at the west end of Wager Bay. Her weight was 232 kilograms she had two cubs of the year, a female 48 kilograms and a male 47 kilograms.
Polar bear #34051 was captured on south western Southampton Island. Her weight was 216 kilograms and her male cub of the year weighed 46 kilograms.
Polar bear #34056 was also captured on south western Southampton Island. Her weight was 198 kilograms. She had one female cub of the year weighing 43 kilograms.
Polar bear # 34058 was captured near the centre of Southampton Island. Inuit regularly observe polar bears crossing this island during the ice-free season. This female was 223 kilograms and accompanied by a single yearling cub that was 138 kilograms.
Polar bear #77012 was captured at the entrance to Wager Bay at Roes Welcome Sound. She was 234 kilograms and her male cub of the year was 61 kilograms
The future
Polar bears are not currently classed as endangered – there are about 22,000 living in the wild, but if current warming trends continue, scientists believe polar bears could disappear within 100 years. |