Peary caribou  (Rangifer tarandus ssp. pearyi)

Classified as Endangered (EN A1b, C1) on the IUCN Red List (2003) (1), listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada (2002) (3) and listed as Endangered by the Species at Risk Act (2003) (4).

The Peary caribou is the smallest of all caribou (a type of reindeer native to northern North America) at around the size of a great dane dog (3). What the Peary caribou lacks in size however it makes up for in its pelage. It has a fantastic long, dense, silky white winter coat to protect it from the harsh cold weather and in the summer develops a shorter coat, which is slate coloured on top and white or ivory-coloured on the underparts (5). This subspecies of caribou has a short deer-like muzzle, and grey velvet antlers which become bone-coloured when the caribou polishes them on the ground (5). Both males and females have antlers, though antlers on the adult males are much larger than those of females and juvenile males (6).

This species is endemic to the High Arctic Islands of Canada that are collectively known as the Queen Elizabeth Islands (3).

Inhabits the harsh environment of the Queen Elizabeth Islands where winters are severe. The land is rocky and covered with ice and snow most of the year. There is little vegetation and the few herbs, grasses, sedges, and lichens are important forage (6).

Peary caribou are found in small groups throughout the year and graze while on the move. They selectively feed on the patchy distribution of high quality food plants throughout the year (7). In the summer they forage in moist areas near river valley slopes and upland plains, feeding on willow, herbs, sedges and grasses (3) (6). Unlike other caribou this species does not eat much lichen, because it is rarely available (6). To obtain food in the winter they dig feeding craters in the snow by pawing with their broad hooves down to the vegetation below (3). Large and concave, the hooves splay widely to support this mammal in the snow, and function as efficient scoops when the caribou is uncovering the vegetation (7). The sharp edges of the hooves also give this mammal a firm footing on ice or smooth rock. Caribou are excellent swimmers when their hooves also function as paddles (7).

Group size is strongly influenced by the overall density of a population. In the winter the Peary caribou can be found in groups of up to five, in pairs, or even as solitary individuals, while in the summer months of July to August after the calving period, they occur in larger groups of five to ten individuals (8). Females migrate to small islands in the spring for calving, after a gestation period of 8 months, and are capable of bearing one offspring annually in June (5) (8). However this depends on whether they can build up adequate fat reserves over the summer to breed in mid-October (8).

Since the early 1960s there has been over a 90% decline in the Peary caribou population and there are concerns that this species is facing a high risk of extinction (9). Research indicates that the Peary caribou population of Canada's western Arctic Islands dropped from 24,320 animals in 1961 to just 1,100 animals in 1997. This figure seems so low that it is thought the population will be unable to recover in the wild (10).

Evidence suggests that the staggering decline in population is attributed to malnutrition caused by severe winters in 1973/74 and again in 1994/95 through to1996/97 (3). These severe winters are thought to be the result of climate change, which is mainly driven by the burning of the fossil fuels oil, coal and gas (10). Severe malnutrition during harsh winters can affect this caribou’s ability to reproduce and look after its young. Peary caribou calves are especially vulnerable as their mothers need to forage on snow-free patches when they are born in mid-June. If snowfalls become heavier, the ground won't be bare, leaving the mothers with insufficient food to produce milk. Also, colder winters create a deeper snow pack which prevents these animals from reaching their crucial winter food supply (10).

Other potential threats include disturbances from resource development and the contamination of Arctic ecosystems (3) (6). Hunting is not believed to be a significant factor in the population decline of the Peary caribou, though it has had a significant effect in the past. Predation by wolves has not been a major threat previously, though with populations at all time lows, it could become a problem (3).

The main threat to this species is the massive and complex problem of climate change. Scientists are monitoring the populations so they can evaluate the best way to protect the remaining Peary caribou (3). Studies involve monitoring herd sizes and movements through aerial surveys and radio and satellite tracking techniques. Calf survival has also been monitored on some islands and attempts are being made to set up a captive breeding program (9). However, there are concerns that removing individuals would reduce breeding numbers in the wild, and possibly fail itself, as these mammals may not breed in an alien environment (5). Traditional local knowledge is being used and Inuit groups are becoming involved in the development and implementation of recovery efforts (9). It is hoped that these local conservation measures will protect this species for the future. The Peary caribou decline highlights the vulnerability of other subspecies of caribou, and indeed all Arctic wildlife, to climate change (10).

For more information on this endangered species see:

• Committee on the Status of Endangered Wildlife in Canada
  http://www.cosewic.gc.ca/eng/sct5/index_e.cfm
• The Smithsonian Institution's North American Mammals website:
  http://www.mnh.si.edu/mna/image_info.cfm?species_id=288