What is the mountain of butterflies? How were they found?
Forty-one years ago researchers discovered the 'mountain of butterflies,'聽the winter home of North American monarch butterflies, after decades of looking.
Forty-one years ago researchers discovered the 'mountain of butterflies,'聽the winter home of North American monarch butterflies, after decades of looking.
After decades of theories about the migration patterns of hundreds of millions of monarch butterflies that dot the meadows of North America in summer, researchers finally discovered what they called 鈥淢ountain of Butterflies,鈥� the monarch鈥檚 winter retreat, in Mexico 41 years ago today.
Every autumn, millions, maybe even a billion, of the iconic orange and black butterflies journey up to 3,000 miles south, from Canada, through the United States and to the high-altitude forests of Mexico鈥檚 Sierra Madre mountains. And that's where they spend their winters, clinging to the branches of the oyamel fir trees of central Mexico, packed in tight clusters to keep warm.
They blanket a small area of a forest reserve that has since been created to protect the trees from illegal logging, 鈥渃olouring its trees orange and literally bending their branches under their collective weight,鈥� according to the Monarch Butterfly Biosphere Reserve, established in 2008 in the forests of Michoac谩n, about 60 miles northwest of Mexico City.
It is said that when they fly en masse overhead, they block out the light, the sound of their collective wing flapping resonates through the sky like light rain. 聽
According to 鈥淣o Way Home,鈥� a book about the growing threats to the world鈥檚 migratory animals by Princeton University ecologist David S. Wilcove, the monarch鈥檚 winter home was discovered in 1975 thanks to efforts by Canadian entomologist Fred Urquhart, who had been trying to find it since the 1930s.
Dr. Urquhart was able to finally track the monarchs鈥� migration by marking their wings with a tiny adhesive tag that identified each one and instructed anyone who found it to notify him. By 1975, and with the help of a publicity campaign in Mexico that galvanized the public around his mission to find the winter home of the monarchs, Urquhart prevailed, wrote Prof. Wilcove.
Although, the "mountain of butterflies" was known to Mexican locals well before 1975, its role in the monarch migration was not well understood.聽
Wilcove quotes Urquhart鈥檚 first impressions of the colony, which he likened to a 鈥渃athedral where one should converse in whispered tones for fear of breaking the enchantment.鈥�
In the decades since the monarch鈥檚 winter colony was discovered, winter migrations have declined dramatically along with the insect鈥檚 population, as the butterfly鈥檚 source of food and reproductive habitat, milkweed, has been lost due to pesticides use and rapid development.
But there are multi-national efforts underway, as 海角大神 has reported, to preserve the butterfly population, including a push in the United States and Canada to encourage farmers and citizens to plant more milkweed.