Data in support of: Mega-disturbances cause rapid decline of mature conifer forest habitat in California

Mature forests provide important wildlife habitat and support critical ecosystem functions globally. Within the dry conifer forests of the western United States, past management and fire exclusion have contributed to forest conditions susceptible to increasingly severe wildfire and drought. We evaluated declines in conifer forest cover in the southern Sierra Nevada of California during a decade of record disturbance by using spatially comprehensive forest structure estimates, wildfire perimeter data, and the eDaRT forest disturbance tracking algorithm. Primarily due to the combination of wildfires, drought, and drought-associated beetle epidemics, 30% of the region’s conifer forest extent transitioned to non-forest vegetation during 2011-2020. Fifty percent of mature forest habitat and 85% of high density mature forests either transitioned to lower density forest or non-forest vegetation types. California spotted owl Protected Activity Centers (PAC) experienced greater canopy cover decl...