Migratory monarch butterflies face rising threats, and they were recently listed as endangered on the International Union for Conservation of Nature’s Red List. In 2021, we shared our intention (alongside Google.org) to restore and enhance habitat for monarchs and other pollinators across California, including creating more habitat on our own campuses.

We’ve seen promising early results from these efforts. Over the past year, we’ve helped restore and enhance more than 500 acres of habitat across California. We also measured strong increases in the presence of monarch eggs, caterpillars and butterflies at our campus project sites.

There’s still a long way to go. But by sharing more about our work to help both people and nature flourish in the campus and communities we call home, we hope to inspire others to take action.

Planting milkweed to attract monarchs

Since 2021, Google’s real estate team has completed more than 35 monarch habitat projects on our California campuses, totalling roughly nine acres of new and enhanced habitat. The completed projects were installed primarily on our Mountain View and Sunnyvale campuses, as well as in Palo Alto, Santa Barbara and Los Angeles. We continue to maintain and refresh the plantings as needed.

Project sites — ranging from just a few hundred square feet to nearly an acre — take the form of native pollinator gardens woven into our campuses. We’ve used the best available science to create the right mix of milkweed plants, which support monarch eggs and caterpillars, and flowers, which support butterflies passing through on their long migration. In total, we planted over 4,400 milkweed plants — enough to fill an Olympic-size swimming pool.

After a year of monthly monitoring trips to measure monarch activity at habitat project sites and control sites (areas without new monarch-related plantings) in Mountain View and Sunnyvale, we’ve seen clear signs of success. On average, when comparing habitat project sites with control sites, the presence of monarch eggs was roughly 6 times greater and of caterpillars roughly 10 times greater, and there were measurably more monarch butterflies as well.