June 24, 2011

Caribou In Athabasca Oil Sands Threatened By Human Presence

The caribou population in the Athabasca Oil Sands area in Alberta, Canada could be extinct in 30 years due to human activity, according to new research.

Wolves have been blamed for the dwindling caribou population in parts of Alberta, but research published in the June issue of Frontiers in Ecology and the Environment says human activity related to oil production and the timber industry could be more important than wolves in the caribou population decline.

Samuel Wasser, a University of Washington conservation biologist, said that while the drop in caribou and moose numbers in recent years is unmistakable, the populations have held relatively steady in the last four years.

The Athabasca Oil Sands deposits are so large that it is second only to Saudi Arabia as a potential petroleum source.

North American Oil Sands Corp. asked for Wasser to help determine what was happening to caribou, moose and wolf populations in the Athabasca Oil Sands region south of the city of Fort McMurray, where the company held oil leases.  Wasser began using non-invasive methods he developed to acquire DNA and hormone data from scat samples located by dogs.

The research focused on whether the caribou population decline resulted from habitat changes due to roads and other infrastructure associated with the oil and forestry industries, from physiological stress caused by human activity, or from excessive wolf predation brought on by increased numbers of deer.

The scat samples from caribou, moose and wolves were collected in the winters of 2006, 2007 and 2009.  Four teams of highly trained scat-detection dogs led to the recovery of 2,000 samples of caribou, moose and wolf scat in 10 weeks.

The researchers determined after examining the samples that habitat preferences for each species, their abundance, the type and quality of food consumed and hormone levels could indicate whether the animals were under psychological or nutritional stress, or both.

The team found that deer made up 80 percent of wolves' diet, with caribou and moose accounting each for about 10 percent.

Moose favored habitat associated with food and were not affected by the presence of people.

However, caribou chose open, flat areas where they could see and hear predators and escape.  These areas also made it easier for them to see and hear humans on the landscape.  Their scat reflected high stress and low nutrition in areas near roads when humans were most active.

The research also produced the first precise number of the caribou, moose and wolf populations in the habitat.  As of 2009, the scientists estimate 330 caribou, 387 moose and 113 wolves live within the small section of oil sands. 

The tools developed to evaluate scat samples for evidence of habitat selection, population changes, nutrition and stress will also provide the means to tell quickly whether mitigation efforts are working or if changes are needed.
"They would be able to make course corrections quickly and effectively," Wasser said.


Image 2: A University of Washington dog handler accompanies a scat-detection dog in the oil sands region of northern Alberta. The dog has been trained to locate scat from a wide variety of species, which is used to determine wildlife abundance, distribution and physical health across large remote regions. Credit: Center for Conservation Biology/University of Washington


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