Caribou (Rangifer tarandus), or reindeer as they are known in the Old World, are ubiquitous Arctic herbivores, found from Northern Scandinavia across the Russian Arctic, Alaska, the tundras of Northern Canada and in Western Greenland. A former population in Eastern Greenland, that some scientists believe to have been a separate subspecies, was driven extinct in the nineteenth century (Caribou taxonomy is not clear; there are clearly several subspecies, but different authorities do not agree on how they should be defined). They are widely domesticated, both for their meat, and as a beast of burden, and wild herds are hunted by indigenous peoples across much of the Arctic. Because of the widespread domestication of Caribou the species is not in danger of extinction, but wild herds have suffered sharp declines in numbers in recent decades, something that has been widely blamed on increased human activity in the Arctic.
A Caribou on the Tundra of Quebec.
A study for the human rights group Survival International released last month, found that the world's largest wild Caribou herd, the George River Herd, which roams across the tundras of northern Quebec and Labrador, has fallen from around 800 000 in 1993 to about 74 000, a loss of slightly over 90% of the population. The Canadian Government has also been monitoring the herd, and has recently introduced tougher restrictions on reindeer hunting in the area.
The study by Survival International, which concentrates on witness statements from Innu Tribal Elders, does not see hunting as the main reason for the George River Herd's decline, but rather suggests the herd may have been effected adversely by increasing industrialization in the area, particularly extraction of iron ore from the Labrador Trough, a geological feature that runs across Labrador and Quebec, by mining company Cap-Ex Ventures and the rising number of road-building and hydro-electric projects in the area.
While this initially sounds persuasive, Caribou populations are naturally prone to severe population fluctuations. As recently as 1950 the total Caribou population for Labrador and Quebec was estimated to be as low as 5000, divided into two herds, the George River and the Leaf. These fluctuations are thought to be caused by the grazing habits of the Caribou. In good times the population of Caribou grows steadily, till there are more Caribou than the environment can sustain, then overgraze their food supply, leading to widespread starvation and a general population crash. This then allows the environment to recover, whereupon the Caribou numbers start to rise again. This is bad for individual Caribou, but not necessarily a bad thing for the species, as the periodic crashes weed out less fit individuals and serve to keep down predator numbers, be they wolves or hunting permits.
Obviously reducing the total grazing are available will reduce the maximum population size the herd can reach, and therefore bring about the population crash sooner, but it does not necessarily follow that a dramatic crash in Caribou populations can be completely attributed to human activity.
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