Beavers Invade Canada's Arctic as Climate Change Expands Their Range

A new study published in Ecosphere reveals that beavers have inhabited one of Canada’s northernmost regions since at least 2008. Researchers used tree ring records to reconstruct part of the species’ past range, filling gaps in historical data. The findings highlight how climate change is driving beavers further into the Arctic. Scientists have long struggled to track beavers’ historical movements due to limited observational records. To address this, the study analysed tree rings to piece together evidence of past occupancy. The results confirm continuous beaver colonisation in the Inuvialuit Settlement Region since 2008.

The central site in the region showed signs of beaver activity between 2015 and 2022. The northernmost site had evidence of occupancy from 2008 to 2022, while the southernmost site recorded beavers between 2011 and 2023. As they move north, beavers build dams and create new ponds, reshaping the landscape.

These changes can disrupt water flow, sometimes forming habitats for waterborne diseases or blocking transport routes. Historical data on beaver expansion helps researchers predict future shifts and link landscape alterations to their activity. The study provides clear evidence of beavers’ northward spread in the Arctic. This information allows scientists to better understand and anticipate the ecological impacts of their growing presence. It also offers a tool for attributing environmental changes to beaver behaviour.