This report provides an assessment of overwintering sites of western populations of the monarch butterfly in California. From data collected at over 400 sites, the report summarizes existing overwintering trends and identifies the highest priority sites for active management and protection.
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The western monarch migration is on the verge of collapse. Learn more, including how to help.
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Western Monarch Ecology and Conservation – San Francisco, CA
New Year’s Count of Western Monarchs Confirms Decline, Trends Seen in Previous Years
Record Low Number of Overwintering Monarch Butterflies in California—They Need Your Help!
Early Thanksgiving Counts Show a Critically Low Monarch Population in California
Our newest book introduces you to a variety of butterflies who need our help, and provides suggestions for native plants to attract them, habitat designs to help them thrive, and garden practices to accommodate all their stages of life.
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Following news of the dramatic decline in monarch numbers, some people are rearing large numbers of monarchs in backyard operations or obtaining them from commercial breeders or other organizations and releasing them with the goal of supplementing local populations. But are such efforts doing more harm than good?
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