Northern Cordillera forests

Content Cover Image

Atlin, Yukon Territory, Canada Photograph by J. Peepre

This ecoregion represents a combination of alpine, subalpine, and boreal mid-Cordilleran habitats across much of northern British Columbia and southeastern Yukon. The northern Cordillera forests extend across northern British Columbia, southern Yukon Territory, and cover a minute area in the Northwest Territories.


 

The mean annual temperature for this ecoregion is generally -2°C, mean summer temperature is 10°C, and mean winter temperature ranges from -13°C to -18.5°C. Mean annual precipitation is approximately 350-600 millimeter (mm), but increases up to 1,000 mm at higher elevations.

This ecoregion includes a number of different physiographic features: the northern Rocky Mountains in northern British Columbia; the Hyland Highland in southeastern Yukon north of the Liard River; the Liard Basin, a broad, rolling low-lying area; the complex, rugged Boreal Mountains and Plateaus; the Yukon-Stikine Highlands in the rain shadow of the Coast Mountains; and the Pelly and northern Cassiar Mountains. Discontinuous permafrost with low ice content occurs throughout the ecoregion, usually confined to lower, north-facing slopes.

Biological Distinctiveness

caption Mountain goat (Oreamnos americanus). (Photograph by Lorraine Elrod, California Academy of Sciences & CalPhotos)

Vegetation associations in this ecoregion follow elevational gradients. Alpine communities include dwarf ericaceous shrubs (Ericaceae), dwarf birch (Betula sp.), willow (Salix spp.), grass (Gramineae), lichen, and bare bedrock at elevations above the tree line. Subalpine forests are characterized by alpine fir (Abies lasiocarpa), black spruce (Picea mariana), and white spruce (P. glauca) together with deciduous shrubs, and occasional Engelmann spruce (P. englemannii). Closed boreal forests at lower, warmer elevations include white and black spruce, lodgepole pine (Pinus contorta), and some paper birch (Betula papyrifera) and aspen (Populus tremuloides). Lodgepole pine and aspen regenerate following fires, which is the principal form of renewal for forests in this ecoregion.

Characteristic wildlife include moose (Alces alces), wolverine (Gulo gulo), snowshoe hare (Lepus americanus), black bear (Ursus americanus), grizzly bear (U. arctos), mountain goat (Oreamnos americanus), pika (Ochotona collaris), bison (Bison bison), Stone’s sheep (Ovis dalli spp.), Dall’s sheep (Ovis dalli spp.), weasel (Mustela spp.), red fox (Vulpes vulpes), beaver (Castor canadensis), muskrat (Ondatra zibethica), Arctic ground squirrel (Spermophilus parryi), spruce grouse (Dendragapus canadensis), ptarmigan (Lagopus spp.), snowy owl (Nyctea scandiaca), raptors, waterfowl, crane (Grus canadensis), and ruffed grouse (Bonasa umbellus). Many species of wildlife reach either their continental southern or northern range limits in this ecoregion. A large and intact predator prey system including wolves (Canis lupus), grizzly bears, caribou (Rangifer tarandus) and moose (Alces alces). There are especially high concentrations of grizzly bears in some of the valley lands.

Conservation Status

Habitat Loss and Degradation

Much of the region (85 percent) remains as intact habitat. New and increasing natural resource development are increasing human pressure on this ecoregion. This includes major mining (open pit) sites, hydro-electric impoundments, logging and transportation corridors.

Remaining Blocks of Intact Habitat

Most of this ecoregion remains intact.

Degree of Fragmentation

Road networks, including logging and mineral/oil exploration roads, are the principal causes of habitat fragmentation. These are of increasing concern throughout the ecoregion as they create access to new areas and disrupt the movement patterns of large carnivores and ungulates.

Degree of Protection

  • Spatsizi Plateau Wilderness Provincial Park - northern British Columbia - 6,082.25 km2
  • Atlin Provincial Park - northern British Columbia - 2,326.95 km2
  • Mount Edziza Provincial Park - northern British Columbia - 2,287.02 km2
  • Stikine River Recreation Park - northern British Columbia - 2,170 km2
  • Kwadacha Wilderness Provincial Park - northern British Columbia - 1,144.44 km2
  • Tatlatui Provincial Park - northern British Columbia - 1,058.29 km2
  • Muncho Lake Provincial Park - northern British Columbia - 884.16 km2
  • Gladys Lake Ecological Reserve - northern British Columbia - 485.60 km2
  • Kwadacha Recreation Park - northern British Columbia - 440.31 km2
  • Atlin Recreation Park - northwestern British Columbia - 384.45 km2

Types and Severity of Threats

The types and severity of threats are both increasing. Timber harvesting is heaviest in riparian spruce and poplar areas, and upland lodgepole pine areas. Wildlife exploitation is now considered high in southeastern Yukon and moderate in the British Columbia portion of the ecoregion.

Suite of Priority Activities to Enhance Biodiversity Conservation

Protected areas needed in British Columbia include:

  • Muskwa-Kechika Wildlife Area
  • Jennings Plateau
  • Lower Stikine River Corridor
  • Taku
  • Tutshi
  • Kawdy Plateau/Lord Mountain
  • Liard Eskers

Conservation Partners

  • Canadian Nature Federation
  • Canadian Parks and Wilderness Society, Yukon Chapter
  • Canadian Parks and Wilderness Society, British Columbia Chapter
  • Friends of Yukon Rivers
  • Northwest Wildlife Preservation Society
  • The Nature Conservancy, British Columbia
  • World Wildlife Fund, Canada
  • Yukon Conservation Society

Disclaimer: This article is taken wholly from, or contains information that was originally published by, the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.

 

Glossary

Citation

Fund, W. (2014). Northern Cordillera forests. Retrieved from http://www.eoearth.org/view/article/154915

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