A monarch butterfly lands on a hibiscus flower in Virginia.
A monarch butterfly lands on a hibiscus flower in Virginia.
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The Oyamel forest at El Rosario sanctuary in Angangueo, state of Michoacan, Mexico.
The Oyamel forest at El Rosario sanctuary in Angangueo, state of Michoacan, Mexico.
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Millions of monarch butterflies arrive each year to breed in the Oyamel forest in Angangueo, after traveling more than 4,500 kilometers from the United States and Canada.
Millions of monarch butterflies arrive each year to breed in the Oyamel forest in Angangueo, after traveling more than 4,500 kilometers from the United States and Canada.
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Monarch butterfly larva.
Monarch butterfly larva.
Courtesy of Sonia Altizer
Monarch Butterfly Biosphere Reserve in El Rosario in Mexico.
Monarch Butterfly Biosphere Reserve in El Rosario in Mexico.
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The decline of monarch butterflies is a cause of concern among conservationists.
The decline of monarch butterflies is a cause of concern among conservationists.
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