Bodies of evidence
Something is awry in the Arctic’s complex food chain. What can polar bears, caribou and other top predators tell us about the North’s rapidly changing landscape?
Understanding changes taking place in the northern landscape involves untangling a set of soil, hydrology, plant, animal and human linkages. How vegetation responds to local warming, for example, has significant consequences on grazing animals and on the humans who hunt them. One place to look for clues to environmental change is in the very blood and bone of the animals that live there.
Researchers working on International Polar Year (IPY) projects are monitoring the health of caribou populations, noting the size, physical condition and movement of various herds. Caribou subsist on low-lying mosses or lichens they scrape off the tundra with their hooves. Yet this food source could become scarcer as the tundra warms, forcing these animals to adapt in order to survive. A general warming of the climate could also bring new types of parasites and infectious diseases.
The impact of climate change on polar bears is also being examined by IPY investigators. As one of the Arctic’s most accomplished hunters, polar bears hold a key position in the Arctic food chain. Researchers are studying the polar bear’s foraging ecology, including changes in their feeding patterns and the correlation of seal and polar bear growth. Among other questions, investigators are trying to determine how levels of chemicals in polar bear fat and liver tissues have varied over time. Like caribou, polar bears can find themselves affected by changes in climate, altering their diets.
For the Aboriginal populations of Canada’s North, animals occupy important cultural, spiritual and economic roles. Northerners are keenly interested in what the IPY projects will uncover, and are working with scientists from around the world to gain a deeper understanding of the changes shaping their landscape and what those changes may mean for their way of life.
This piece highlights the significance of Caribou to scientists studying the effects of climate change on our Northern ecosystems. Users are invited to select from a series of regions to learn more about specific herd movements, and their impact.