State of the Monarch Butterfly Overwintering Sites in California

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.

State of Overwintering Sites_cover_june2016





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Monarch Conservation News
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  • Gardening for Butterflies
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    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. Click here to read more
    On Captive Breeding and Release of Monarchs
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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? Click here to read more