Yosemite’s old-growth forests provide important habitat for the California spotted owl, a candidate for the endangered species list. Recent wildfires have swept through prime habitat for this species, which is also facing a threat from an invasive look-alike, the barred owl.

Donor-supported research has revealed that many of Yosemite’s owls have returned to burned areas. In 2017, researchers applied data from 3-D canopy surveys to examine spotted owl nest trees inside and outside fire footprints, and studied how blazes have affected the birds’ breeding.

Scientists also continued to study how wildfire affects Yosemite’s great gray owls. Over the course of their field season, they collected more than 300 great gray owl feathers, and detected the birds at almost all survey sites.

Your contribution helped scientists collect valuable data to inform fire-management and explore how Yosemite can serve as a refuge for owls and other threatened wildlife. To learn more about avian research in the park, read our blog post about studying owl occupancy.

Completed in partnership with Yosemite National Park, Institute for Bird Populations, National Science Foundation Research Experience for Undergraduates and Student Conservation Association.

Sarah Stock

Wildlife Biologist

Project Notes

Investigating how spotted owls respond to fire, and how a protected area like Yosemite can serve as a refuge for threatened species facing competition from invasive species, are essential research questions to inform future land management and listing decisions.