Species of special interest

Photo: caribou © Anne Gunn

Caribou

Caribou are distributed across most of Canada and can play important ecological roles as herbivores influencing the structure of plant communities, as prey supporting populations of large and medium-sized predators and scavengers, and as a source of nutrients in otherwise nutrient-limited systems. Caribou are an integral part of many cultures, particularly Aboriginal cultures, which have developed with caribou over thousands of years.1

This section is further divided into the following two topics:

Globe

Global Trends

Caribou and reindeer have a circumpolar distribution in the world’s tundra and boreal zones. Wild populations have declined in Russia and are mostly extirpated from Europe, except for a small, stable reindeer population in Norway, and an increasing population in Finland.28 Loss of habitat and climate change are threats worldwide.29

Caribou of the Arctic and taiga

Caribou of the Arctic and taiga population trends
Based on information available in August 2010
Map: Caribou of the Arctic and Taiga population trends. Click for graphic description (new window).
Source: adapted from Gunn and Russell, 2010,2 CARMA, 2009,10 Magoun et al., 2005,15 Elliot, 199816

Abundance of northern caribou, like other northern herbivores, such as lemmings and hares, is cyclic. Caribou numbers generally increased from lows in the mid-1970s to peaks in the mid-1990s, returning to lows by 2009 that are, in some cases, similar to previous lows.2 Some herds, notably the Bathurst and Beverly, which calve in the central Arctic, have experienced severe drops in the past few years.3, 4 Current declining trends may be partly related to natural cycles in abundance.2

Abundance of Peary caribou, which live on the High Arctic islands and are listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC),5 is largely influenced by weather. Periodic severe winters trigger large-scale mortality and reduction in productivity.5 Populations have declined by as much as 98% on several islands.6, 7 During two winters in the 1990s, more than 95% of the Peary caribou population in the western half of its range was devastated by heavy snow and the formation of ice layers in the snow.6 Events like these are projected to become more frequent and more widely distributed with climate change.6, 8, 9

Significant changes on caribou ranges since the 1970s could prevent a recovery of some herds to previous peak numbers.10 These changes include the effects of climate change, including changes in wildfire,11 and an increasing presence of people and development, particularly mining and oil and gas activity.12-14 Caribou harvest by humans and predation are also known to affect abundance within some caribou herds.5

Forest-dwelling woodland caribou

Map and graphs: status and range of forest-dwelling woodland caribou populations. Click for graphic description (new window).
Source: range for boreal population and southern boundary of historical extent adapted from Environment Canada, 2008,17 range for southern and northern mountain populations adapted from Thomas and Gray, 200218

Forest-dwelling woodland caribou are relatively non-migratory and live in smaller groups than their northern counterparts. They divide their time between lichen-rich mature forest and open areas, including alpine tundra.18 Historically occurring over much of Canada, their distribution has retracted, with the southern boundary continuing to move northward.18, 20 Caribou had completely disappeared from Nova Scotia and New Brunswick by 1930.21

The status of many herds remains unknown; however, where data exist, declines are evident, particularly for the boreal17 and southern mountain populations.22 Woodland caribou are declining primarily because of loss and degradation of habitat and landscape fragmentation due to roads and other linear features. This is resulting in the isolation of populations and increasing vulnerability to predators.17, 23-25 Overharvest of the caribou, fire, and climate change are also considered factors in population decline.17, 18, 26 Generally, populations that are stable or increasing occur in remote areas with little or no industrial activity or where predator control has been used as a management tool.27

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