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The Frontlines of Global Climate Change

Alaska and the northwest corner of Canada are at the frontlines of global climate change. While average worldwide temperatures have increased by one degree Fahrenheit, averages up here have climbed as much as 11 degrees in some places. Biologists like Steve Arthur are researching how such changes may be affecting species like caribou that have survived in this harsh environment for more than a million years. While herd numbers naturally fluctuate, the Porcupine caribou herd that Arthur studies has been declining at a steady rate since 1989. At that time, there were about 187,000 caribou in the herd. Now numbers are hovering around 120,000.

What makes you most hopeful for the future?
Arthur: “Biological systems are remarkably adaptable. The environment may change, but life goes on. The difficulty is in finding ways to avoid changing these systems in ways that humans perceive as harmful...”

See Steve Arthur's full Q&A »

What do you like best about your profession?
Elias: “I love being out living and working in the natural world with the water, land and wildlife. I learn something new and exciting about the relationships between living things every day I'm out there...”

See Darius Elias' full Q&A »

Several causes may underlie this decline. Warmer weather can lead to longer breeding periods for mosquitoes that suck up to a tablespoon of blood a day from each caribou during the summer months. Such annoyances can distract caribou from foraging, reduce overall food uptake and reserves and ultimately lead to lower numbers of calves being produced. Finding enough food is also becoming challenging in the winter since rising temperatures are bringing more precipitation, more snow. More snow not only buries food deeper but makes avoiding predators like wolves much more difficult. A combination of rough winters with short rations followed by summers spent dodging mosquitoes can leave caribou weak, run down and less likely to survive and reproduce.

The prospect of losing caribou raises unsettling questions regarding the future of native peoples like those from the Gwich'n First Nation. The Gwich'n have survived in this forbidding landscape for over 10,000 years, harvesting plants and animals from the land. The caribou are pivotal to their culture. As member Darius Elias eloquently states, "The blood when you grow in your mother's womb, a lot of that nutrition comes from the caribou... that's where it starts. You grow up on it... the Gwich'n relationship with the ecosystem that's thousands and thousands of years old, if that's gone, to me, that would impoverish mankind."

Next: Regime Shifts and the Food Web »


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