Endangered Species Breeds in Yosemite for First Time in 25 Years

Yosemite National Park has witnessed the successful breeding of the state-endangered Willow Flycatchers for the first time in over two decades.

Park rangers reported that a pair of Willow Flycatchers (Empidonax traillii) bred in Ackerson Meadow in July 2023, marking a major conservation success. The pair successfully fledged two offspring, and the family subsequently embarked on their seasonal migration.

The breeding success in Ackerson Meadow is particularly notable given the challenges the species has faced. Historically, over a century of certain meadow use practices significantly reduced suitable breeding habitats for Willow Flycatchers across the Sierra Nevada. This bird species, while generally common, includes the southwestern Willow Flycatcher which is a federally listed endangered species. Their populations have been particularly threatened by factors such as Brown-headed Cowbird parasitism, habitat loss and degradation, and overgrazing.

Efforts to restore the meadow and floodplain hydrology at Ackerson Meadow have been critical. By improving conditions for Willow growth— the bird’s preferred habitat—Yosemite park rangers hope to further support and increase the Willow Flycatcher population.

The Ackerson Meadow Restoration Project is set to continue enhancing habitat conditions into 2024 and beyond, aiming to provide a sustainable environment for these birds and other wildlife dependent on these ecosystems.