Monarchs are the only butterflies that migrate between a summer and winter habitat. Scientists believe the changes in daylight and temperature at the end of summer signal to monarchs that it is time to begin their migration. 100 million monarchs begin their journey to their winter habitats starting in September through November.
Gliding & Rest Stops, You Can Help Them On Their Journey
Along the way, they seek out thermal columns of warm air, that give them a lift and help them glide using less energy. They stop frequently to feed on nectar and to drink water. You can help them along their journey by planting your garden with flowers they feed on. Monarchs drink nectar from milkweed, goldenrod, clover, thistle, purple coneflower, sunflowers, cosmos, zinnias, marigolds, and my personal favorite Pineapple Sage.
So, Where Are They Going?
Many people don't realize that even though of the exact same species, western and eastern monarchs over-winter in completely different areas.
Monarchs west of the Rockies migrate to California to spend the winter, where they take shelter in eucalyptus, pine, and cypress trees. While monarchs east of the Rockies have a much further journey - these monarchs fly over 2,000 miles to get to their winter habitat in Michoacán, Mexico, where they take shelter in oyamel firs and cypress trees.
A single tree will shelter thousands of butterflies on it. These sites are under threat as they are being deforested at an alarming rate, putting the future of the monarch in jeopardy.
Staying Alive During The Winter - Harder Than You Think
During the winter the main job of the monarchs is to stay alive. Which isn't as easy as you might think, especially for the eastern monarchs. Considering they fly so far south, you'd think they'd be enjoying balmy, sunny winters. However, the spot they choose in Michoacán, Mexico happens to get pretty chilly at night (below freezing at night). The monarchs huddle together in thousands for protection from the weather. The cool temperatures slow down the monarchs’ body processes and help them use less water and energy. They live off the fat and water stored in their abdomens.
Plant a Monarch Garden - Get a Free Packet of Seeds
The number of Monarchs has declined sharply in the last 30 years due loss of habitat. Milkweed is the only plant that Monarch's lay their eggs on (although adult butterflies feed on the nectar from a variety of plants). However, Milkweed is crucial to reproduction. The amount of Milkweed in the United States is in decline due too pesticides and herbicides used on corn & soybean fields. Scientist are encouraging people to plant Monarch gardens to help support the monarch and reduce their decline. You can get a FREE packet of seeds that support Monarchs via this link: http://www.livemonarch.com/free-milkweed-seeds.htm
Excellent Video on the Monarch's Migration: