Your Sightings! >>
Today's Report Includes:
- The
Migration:
Maps and Highlights
- Final Fall Migration Maps
- The Overwintering Season Has Begun!
- What Makes This Place So Special for Monarchs?
- Teacher's Guide: So Many Monarchs in Such a Small Place >>
- See You in February When Journey North Begins! >>
The
finish line!
The entrance of "El
Rosario" Sanctuary near Angangueo, Michoacan, Mexico.
 |
 |
 |
As we close the curtain on this fall’s migration, monarchs are still migrating to Mexico. They are streaming southward from points far and wide. Most should be in northern Mexico now, and many millions will make it to the wintering sites, as wind, weather and good luck allow. How many monarchs will survive the trip? That's impossible to know about individual butterflies, but the size of this year's population will be measured in mid-winter. When the news is available we'll add it to this population chart.
Over the past 10 weeks we followed the monarchs as they traveled across eastern North America to a very small region in Mexico. Within the region, only 12 sites have the habitat the butterflies need to survive. Last week, we challenged you to find the sites by looking at a satellite image:
Where
do you think the 12 overwintering
sites are?
Take a look! >>
Very few places in Mexico have the habitat monarchs need. Here is a tale that illustrates how rare their high mountain habitat is:
Dr. Fred Urquhart discovered the location of the monarch overwintering sites in Mexico, after pursuing migrating monarchs for nearly 40 years. He told the world in the August, 1976 issue of National Geographic magazine. However, he did not reveal the actual location of the butterfly colonies, even to other scientists. Nevertheless, Dr. Lincoln Brower and Dr. Bill Calvert were able to find the sites by following two geographic clues they found in the article. The scientists were able to pick out the spot on a map—and travel there—by knowing only that the butterflies were 1) in state of Michoacan and 2) at an elevation of 10,000 feet.
- Read Discovery Tale: Two Clues Led the Scientists to the Monarchs >>
National Geographic announced Dr. Urquhart's discovery >>
Most of North America's monarchs spend the winter—together—in an astonishingly small region. These butterflies are the primary seed stock of our continent's monarch butterflies.
- Notice how small the over-wintering region is, and how little of the area has suitable habitat for monarchs! (See map.) By mid-winter the monarchs at each colony will form such tight clusters that the entire population will cover an area of only 5-50 acres (2-20 hectares). (See graph of winter population measurements.)
- Make a personal connection: On a map of your state or province, measure out an area the same size as the monarch's over-wintering region.
- Consider benefits and threats: What are the risks of having the monarchs over-winter in one small region? What are the benefits?
If the monarch overwintering region were near Chicago...
Teacher's Guide >>
Thank you for helping to track the monarch's fall migration. Over 1,100 people reported observations this fall. Every one was important, whether many or few monarchs were spotted. We will come back to the monarch's story again with weekly reports starting next February 8, 2008. Please join us! As you will find, the monarch's winter story of survival is as amazing as their spectacular migration. Meanwhile, you can explore these and many more online resources:
- Assessment: Suggestions for Assessment After the Fall Migration Season >>
- Monarch Overwintering Biology: Journey North Resources to Explore >>
- Teacher Guide: The Monarch Overwintering Sites in Mexico >>
- Monarchs for Kids (booklets, photos, videos) >>
- Book and Slideshow: The Magic of Monarch Migration >>
- Go Outside! Watch how monarch butterfly habitat is changing! >>
- Orientation: Welcome to new participants! >>
This is the FINAL Monarch Migration Update. See you in February 2008!
