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WonderMigration fact

Eastern monarch butterflies fly up to 4,800 kilometres from Canada and the United States to the mountains of central Mexico each autumn, yet no single butterfly makes the whole round trip: the yearly cycle takes about four generations.

Monarch butterfly migration

MigrationNatureScienceClimate

The story behind the card

The butterflies that fly south in late summer are a special generation: they live about eight months, while the summer generations before them live less than two. They spend the winter packed by the million on oyamel fir trees in the mountains of Michoacán and the State of Mexico, then start north in spring, lay eggs on milkweed in the southern United States and die. Milkweed is the only food their caterpillars eat. Their children and grandchildren carry on northwards. Where the monarchs wintered was a mystery until January 1975, when Kenneth Brugger and Catalina Aguado (later Trail), volunteers helping the Canadian zoologist Fred Urquhart, found the first colony.

Türkçe oku
Doğu Kuzey Amerika'nın kral kelebekleri her sonbahar Kanada ve ABD'den orta Meksika'nın dağlarına 4.800 kilometreye varan bir yol uçar. Ama bu yolu baştan sona gidip dönen tek bir kelebek yoktur; yıllık döngüyü yaklaşık dört kuşak birlikte tamamlar.

Yaz sonunda güneye uçan kelebekler özel bir kuşaktır: Yaklaşık sekiz ay yaşarlar, yazın doğan önceki kuşaklar ise iki aydan kısa yaşar. Kışı Michoacán ve México eyaletlerinin dağlarında, oyamel köknarlarının dallarında milyonlarca kelebek bir arada tutunarak geçirirler. İlkbaharda kuzeye yola çıkar, ABD'nin güneyinde Asclepias bitkilerine yumurta bırakır ve ölürler. Bu bitkiler, tırtıllarının yiyebildiği tek besindir. Yolu çocukları ve torunları kuzeye doğru sürdürür. Kelebeklerin kışı nerede geçirdiği Ocak 1975'e kadar bilinmiyordu. O ay, Kanadalı zoolog Fred Urquhart'a gönüllü olarak yardım eden Kenneth Brugger ile Catalina Aguado (sonradan Trail) ilk koloniyi buldu.

Sources and further reading

Background reading: Monarch butterfly migration
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