Caribou grazing helps keep Arctic cooler: study
The Arctic climate change story just got more interesting.
New research shows that caribou play a role in climate warming in the Arctic. Despite declining herd numbers, their grazing is controlling plant growth in the Arctic and thus reducing the effect of global warming.
The research was done by Tara Zamin, a PhD student at Queen’s University in Kingston and was published in Journal of Ecology. She worked on the study with Paul Grogan, a Queen's professor.
Caribou are recognized as sources of food and clothing for communities in the Arctic but it is now also being acknowledged as a “key component to controlling tundra plant growth and therefore has been left out of models that project changes in arctic ecosystems and arctic warming.”
Even at low population sizes, caribou restrict tundra plant growth, which indirectly may help restrict climate warming, said Zamin in a statement.
“Plant growth has been increasing in the arctic tundra over the past several decades. These changes in plant biomass could increase climate warming by increasing the amount of heat absorbed by the Earth’s surface.”
The researcher studied the impact of the Bathurst caribou herd in the Northwest Territories for five years — it was at a time when the herd population declined from around 166,000 to 31,000. The Bathurst herd had been made up of around 475,000 caribou in the mid-1980s. She compared plant communities in areas open to caribou grazing and those closed off to it.
Caribou remain an integral part of tundra ecosystem functioning, Zamin concluded. “This means that effective caribou conservation is not only critical to the subsistence needs and cultural identity of northerners, it is key to understanding potential climate change impacts.”
Raveena Aulakh is the Star's environment reporter. She is intrigued by climate change and its impact, now and long-term, and wildlife. Follow her on Twitter @raveenaaulakh