Simple Facts About Moths & Butterflies

20. Entomologists say that one of the most regal insects begin their annual migration from eastern United States and Canada, to Mexico every year from late August to early October. This insect is the Monarch butterfly. They say that these butterflies follow the same migratory path every year, often stopping to rest and recuperate at day's end in the same locations or same tree year after year.

21. The main reason they migrate northward in the spring is to eat the abundant milkweed in the eastern United States, then in fall they return south because the winters are to cold to survive and the milkweed plants die off in the winter. Another important reason they eat milkweed is that it contains toxins poisonous to birds, their biggest predator. The poison in one single Monarch, can kill off 8 birds, but the taste makes the birds sick and so the birds quickly learn to eat another type of butterfly.

22. In Mexico, they say you can see lots of Monarchs with beak marks on their wings where birds have tasted them and then let them go.

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23. After their long flight, the Monarch butterflies usually remain inactive from November to February, in their high-altitude wintering site about 50 miles west of Mexico City. In February and March, the Monarchs fly down to lower elevations and feed and then mate. Then they travel into Texas, where they lay eggs and continue their journey. The Monarch's that develop from these eggs instinctively continue the migration.

24. Monarchs have many wintering sites. Some migrate to northern California, and then on to Oregon, and Washington state, and into western Canada, before returning to Mexico. Others mirgrate to Florida and Arizona. There is one Cuban colony that flies over the ocean to winter in the jungles of Mexico's Yucatan Peninsula. It is said that those that get to see migrating Monarchs, see 200-400 insects on the branch of a tree. But Monarches who are very social insects, when they reach Mexico to winter over, will cover trees with amounts of butterflies in the millions in about 8 different mountainous regions.

25. It is amazing to me that these butterflies can travel the same route every spring, making the journey from Mexico and all the way back to the eastern United States and central Canada, without losing their way, every year.