The People's Insect
Sidedoor
00:00
The Overwintering Sites
Scientists think that inside of these butterfly preserves, one hectare can hold as many as 21 million monarchs. They are semi-dormant, clustered together on trees. Some have enough fat on them to last most of the winter. The rest, they try to flap around and find whatever nectar they can. But they don't all make it.
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