The 2020 to 2021 California megafires and their impacts to wildlife habitat

Abstract

Fire activity during 2020-2021 in California, USA was unprecedented in the modern record. More than 19,000 km2 of forest vegetation burned (10x more than the historical average), potentially affecting the habitat of 508 vertebrate species. Of the >9,000 km2 that burned at high-severity, 87% occurred in large patches that exceeded historical estimates of maximum high-severity patch size. In this two-year period, 100 vertebrate species experienced fire across >10% of their geographic range, 16 of which were species of conservation concern. These 100 species experienced high-severity fire across 5-14% of their ranges, underscoring potentially important changes to habitat structure. Species in this region are not adapted to high-severity megafires. Management actions, such as prescribed fires and mechanical thinning, can curb severe fire behavior and reduce the potential negative impacts of uncharacteristic fires on wildlife.

Keywords

climate change, fire severity, megafire, wildfire, wildlife habitat

Citation

Ayars, Jessalyn; Kramer, H. Anu; Jones, Gavin M. 2023. The 2020 to 2021 California megafires and their impacts to wildlife habitat. PNAS. 120(48): e2312909120.