Sharp declines in Alberta's woodland caribou populations have prompted efforts to cull the wolves thought to prey on the animal. But an analysis of faecal samples from the caribou (Rangifer tarandus tarandus) and wolf (Canis lupus; pictured) reveals that wolves eat relatively few caribou, and in fact prefer deer.

Samuel Wasser at the University of Washington in Seattle and his co-workers used trained dogs to locate and collect 1,914 caribou, 327 wolf and 1,175 moose faecal samples on Canada's vast Athabasca oil sands. They studied the location and chemical composition of the samples as measures of the animals' habitat preferences, diet, stress levels and abundance. They found that caribou are more than twice as numerous as previously thought, but are compromised by the intense human activity on the oil sands.


The authors recommend that instead of removing wolves, human activity should be restricted to certain areas and time periods to give the caribou more room.

Front. Ecol. Environ. doi:10.1890/100071 (2011)