But things are changing – fast. Hotter, drier conditions driven by a climate that is changing much faster at northern latitudes than in southern areas have set the stage for more frequent and intense burns across the boreal region. Well-honed wildlife strategies for living with fire, whether sheltering in water or wetlands or racing to escape the flames, are being tested like never before.
How animals survive big fire seasons depends on more significant human-driven landscape factors. Animals fleeing from fast-moving flames may have to contend with obstacles like highways or roads while already under stress. Meanwhile, climate-driven droughts and hydro dams can leave downstream areas too shallow to provide refuge for fish, turtles or other animals in the event of a fire.
Not only do wildlife need to adapt in real-time to super-charged fire seasons, but they may also need to adapt to very different conditions afterwards. More intense fires have more severe outcomes, not just burning the woody parts of the forest but also burning through organic layers of soils and peatlands while potentially destroying seed sources needed for regenerating forests. More frequent fires mean forests don’t have a chance to regrow to mature and old growth stages before burning again. Combined with hotter and drier growing conditions, the increase in fires puts boreal ecosystems on a new trajectory, with deciduous replacing coniferous forests across the boreal region.
Even though boreal species are well accustomed to fire, these changes present new challenges. Boreal caribou, for example, need older forests that contain lichen food sources that they rely on, particularly in winter. It often takes more than 40 years for a forest stand to replenish its lichen. In the meantime, these areas are much less attractive to caribou. As larger areas experience more frequent and severe burns, species that rely on mature forests will be left with fewer options for places to go.