Because the Bering land bridge once connected North America and Asia, many animal and plant species were able to colonize both continents and are found throughout the taiga.

Due to the harsh climate of the taiga, a relatively small variety of animals inhabit it. Canada's boreal forest includes 85 mammal, 130 fish, and about 32,000 insect species. Insects play a crucial role as pollinators, decomposers of dead organic matter or as a link in the food chain - they are food for many breeding birds during the summer months.