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Bring the monarchs back
Butterflies & Habitat Restoration
California's western monarch population fell from about 1.2 million in 1997 to fewer than 30,000 in 2019. Here's why, and how you can help.
What's threatening monarchs
Tropical milkweed
A non-native plant that stays green year-round, disrupting migration and letting a deadly parasite build up.
The OE parasite
Ophryocystis elektroscirrha shortens lifespans and makes it hard for monarchs to fly.
Predators & disease
The Tachinid fly plus bacterial and viral infections take a further toll.
Habitat loss
Disappearing native habitat is pushing monarchs toward endangered status.
How you can help
- 1Plant native milkweed, especially CA narrowleaf milkweed, not tropical milkweed.
- 2Time your plantings to match the natural season.
- 3Educate others about the dangers of tropical milkweed.
- 4Ask local nurseries to stop selling tropical milkweed.
Go deeper
Our students have also created educational videos on monarch conservation, ask us to see them.