Project goal: Expand critical breeding habitat for monarch butterflies and other at-risk pollinators in Yosemite Valley.

Why this work matters: Pollinators are essential to healthy ecosystems and to our global food system. The world’s pollinator populations, however, are declining, a trend especially evident among monarch butterflies. Data from annual counts coordinated by the Xerces Society for Invertebrate Conservation, a science-driven nonprofit focused on protecting butterflies and other invertebrates, show the number of monarchs in the western U.S. dropped by more than 97% between 1997 and 2018.

Like other pollinators, monarchs are facing serious threats from the loss of meadow ecosystems and the native plants on which they depend, including milkweed, the sole host plant for monarch eggs and caterpillars. Yosemite Valley has the potential to serve as a haven for breeding monarchs, but infrastructure and invasive plants have disrupted critical habitat.

Through this project, which builds on past donor-funded pollinator-focused work, park crews, volunteers and student groups will work together to restore habitat for monarchs and other pollinators in the Valley. They’ll remove non-native plants and plant milkweed and other native flora, focusing on areas that would not recover without active revegetation. In addition to creating a refuge for monarchs, bees and other pollinators, this work will enhance biodiversity in the Valley and restore previously developed sites into healthy meadows bursting with wildflowers.

How your support helps: Your gifts will allow the park to continue creating an oasis for monarchs and other pollinators in Yosemite Valley, while providing opportunities for volunteers and young students to learn about ecological restoration firsthand. (Need more inspiration? The results of recent donor-funded pollinator projects are already visible: If you head to the Valley in the summer, you might catch the dazzling sight of monarch butterflies darting among newly planted milkweed.)

Partnering with Yosemite National Park, NatureBridge and Yosemite-area schools.

David Campbell

Biologist, Yosemite National Park

Project Notes

"Monarch butterfly populations are in freefall. Restoring critical breeding habitat is a major step toward protecting them and other declining pollinators, such as bees."