Boreal Forests

The Forests of the High Northern Latitudes

Boreal forests are the world's largest terrestrial biome and account for more than one quarter of all the forested land on Earth.
Boreal forests are the world's largest terrestrial biome and account for more than one quarter of all the forested land on Earth. Photo © John E Marriott / Getty Images.

Boreal forests are a band of coniferous forests that encircle the globe in the high northern latitudes between about 50°N and 70°N. Boreal forests form a circumpolar ecoregion that stretches across Canada—from Alaska to Newfoundland—and extends across northern Europe and Asia—from Scandinavia to eastern Russia. Boreal forests are the world's largest terrestrial biome and account for more than one quarter of all the forested land on Earth.

Boreal forests blanket a vast range across northern Europe, Asia, and North America. They are bordered by tundra habitat to the north and temperate forest habitat to the south. The tree species present in boreal forests are primarily spruces, pines, and larches.

Boreal forests can be divided into many sub-habitat types, but in general these fall into two categories—the closed-canopy forests and the open taiga. Closed-canopy forests dominate the warmer, southern regions of the boreal forests where the growing season is longer. Open taiga habitats dominate the colder, northern regions of the boreal forests where the frigid temperatures and short growing seasons act to limit species diversity and population densities.

Boreal forests are among the coldest environments on Earth. The coldest temperatures on record for the Northern Hemisphere have been measured in the boreal forests of northeastern Russia.

During the winter, temperatures can drop as low as -65°F in the open taiga. Boreal forests experience little rainfall during the summer months. Instead, precipitation either falls as snow or it condenses onto the landscape as fog. Boreal forests have acidic soils.

Boreal forests support a variety of wildlife that includes Northern saw-whet owls, grizzly bears, black flies, American bitterns, grey herons, snow geese, snowshoe hares, Siberian tigers, muskox, Arctic fox, Arctic wolves, elk, grizzly bear, caribou, and wolverines.

Key Characteristics

The following are the key characteristics of boreal forests:

  • terrestrial biome that accounts for more than one quarter of all the forested land on Earth
  • occurs in high northern latitudes between about 50°N and 70°N
  • low average annual temperatures and extreme cold during winter months
  • among the biomes most vulnerable to the effects of climate change
  • the peatlands of boreal forests are significant reservoirs of carbon

Classification

The forest biome is classified within the following habitat hierarchy:

Biomes of the World > Forest Biome > Boreal Forests

Animals of Boreal Forests

Some of the animals that inhabit boreal forests include:

  • Snowshoe hare (Lepus americanus) - Snowshoe hares inhabit the boreal forests of North America. Snowshoe hares prefer areas with dense vegetation. They feed on a variety of plant materials including buds, twigs, bark, and green vegetation. Snowshoe hares have large feet with thick fur on their soles to help prevent them from sinking into the snow.
  • Siberian tiger (Panthera tigris altaica) - Siberian tigers are a critically endangered subspecies of tiger. They are the largest of all the tiger subspecies. Siberian tigers inhabit the coniferous, deciduous and boreal forests of the Russian Far East. Their range extends along the border of China and North Korea and bounded on the west by the Sea of Japan.
  • Bobcat (Felis rufus) - Bobcats are medium-sized cats that inhabit the boreal forests of North America. Bobcats feed on small mammals such as rabbits, hares, and rodents as well as birds and insects. Bobcats are thought to be the descendants of Eurasian lynx that crossed to North America from Eurasia during the Pleistocene by way of the Bering Land Bridge.
  • Caribou (Rangifer tarandus) - The caribou is a member of the deer family that inhabits the boreal forests and tundra of North America, Siberia, and Europe. Caribou are grazing herbivores that feed on the leaves of willows and birches, as well as mushrooms, grasses, sedges, and lichen.
  • Spruce grouse (Falcipennis canadensis) - The spruce grouse is a member of the gamebird family that inhabits the taiga and closed-canopy boreal forests of North America. Spruce grouse feed on the needles of confers, berries, plants, fungi, and insects. Spruce grouse are prey for foxes, hawks, owls, and coyotes.
  • Boreal chorus frog (Pseudacris maculata) - The boreal chorus frog is a small brown frog that inhabits the wetlands of the boreal forest as well as high elevations in more southern latitudes. Boreal chorus frogs have a distinct call that has been described as sounding like someone running their finger over the teeth of a comb.