Also known as Taiga or coniferous forests, boreal forests grow in icy conditions in the far north. Conifers, a hardy tree well adapted to the harsh climate, dominate these forests.
Boreal Forest Ecology
Boreal forests predominantly grow in the northern hemisphere because there is little land in the southern hemisphere where such trees can grow. Boreal forests often grow around moss-filled bogs and unbroken swathes (long strips of land) in Canada, Scandinavia, Alaska and Siberia. These forests in the north experience short summers with long days and long, cold winters where the sun may only rise for a few hours per day. Winter temperatures can reach –25 degrees Celsius (-13 degrees Fahrenheit).
Boreal forests don’t contain many species with almost all trees being conifers such as pine, fir, spruce and cedar trees. These hardy plants have adapted to withstand the freezing temperatures. Conifers have small waxy needles instead of large leaves. These spiny needles have a smaller surface area than leaves, so are less efficient at photosynthesis, however, during winter there is little sunlight for photosynthesis anyway.
Due to their small size and waxy coating, these spiny needles are protected from the ice and wind unlike broader leaves. And rather than flower, conifers produce seeds inside of cones. These evergreen trees don’t drop leaves in autumn (fall), because re-growing leaves in time for the summer wastes far too much energy.
Mammals of the Boreal Forest
Mammals of the boreal forest spend long winters in icy and freezing conditions, waiting for the short summer growing season when there will be a lot of activity. Even summer in boreal forests is too cold for some cold-blooded animals. Many mammals, however, have adapted to the cold by hibernating or becoming inactive (torpor), during the colder months. Others, such as herds of reindeer will migrate to warmer areas and return in spring or summer.
Many small rodents dig tunnels and burrows to protect from the snow and cold. Some of the mammals that can be found in boreal forests are:
- Marmot
- Lynx
- Moose
- Wolverine
- Siberian tiger
- Grizzly bear
- Brown bear
- Rabbits
- Grey wolf
- Weasel
- American red squirrel
Growth is slow and intermittent in boreal forests and because of this, there are usually fewer animals in boreal forest compared with other forests, such as tropical or temperate forests. Mammals that do live there tend to be larger than their southern relatives. Canadian grizzly bears are larger than grizzlies in the south, and the Siberian tiger is the world’s largest cat species. Even smaller mammals such as the rabbit, tend to be larger in the north.
This size difference is an adaptation to the colder climate. Larger animals need to eat less food per unit of body weight than smaller animals because large animals have a larger mass to surface area. This means that larger animals lose heat more slowly than smaller animals and don’t have to burn food at such a high rate.
Resource and further reading:
Hickman, Roberts, Larson & I’Anson, 2004, ‘The Biosphere and Animal Distribution’ in Integrated Principles of Zoology, 12th edition, ed. McGraw Hill, New York, chapter 37.
Roberta Goli - Roberta has a Bachelor of Science Degree (Zoology), has worked with animals for over 10 years and enjoys writing short stories and flash ...
