Monarch Migration Update: March 18, 2005
Today's Report Includes:
- Here Come the Monarchs!
- Final Field Notes from Mexico by Dr. Bill Calvert
- Not All Monarchs Go to Mexico: A Pre-migration Map
- Mass Migration in California--But Were They Monarch Butterflies?
- What Does the California Expert Think?
- What Does Monarch Migration Look Like in the Spring?
- Painted Lady Butterflies: An "Outbreak and Migrate" Life History
- What do YOU Think? Challenge Question #7
- Try This! Practice With Butterfly Identification
- Monarch Winter Habitat: Assessment Suggestions
Here Come the Monarchs!
"We witnessed a massive movement of monarchs," wrote Carol Jordan from Mexico last Thursday. Carole is a Mississippi native who spent the winter in the region. "It was quite a sight!" she exclaimed. At one point, butterflies were numerous enough "for me to put my hazard lights on and to slow down, so as not to hit the low flyers," she stated. Here is her first-hand account:
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Photo
Gallery: Butterflies in Flight Courtesy of Dr. Lincoln Brower Sweet Briar College |
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Final Field Notes from Mexico by Dr. Bill Calvert
The monarchs are definitely on their way, Dr. Calvert confirmed. Late last week and over the weekend "there were three days of very, very hot weather. That's when they left in great numbers and went north," he said on Thursday. Of course, millions of monarchs remain. It will take over a month before all of the butterflies have left the over-wintering region.
As this year's over-wintering season ends, Dr. Calvert offered these departing words: "Every year it's a little different. Nature provides us with some interesting natural experiments to test our ideas about how things are. I hope we are paying attention."
Not All Monarchs Go to Mexico: A Pre-migration Map
This map shows where people saw monarchs in January and February this year. Do any of the locations surprise you? Keep this map in mind as you prepare to track the migration this spring.
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| Monarch
Sightings Jan. 2005 - Feb. 2005 |
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Monarchs in Texas in February, 2005 Photos Courtesy of D. Repasz |
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Try This: Predict
the Route of the Monarch's Spring Migration
As the monarchs pour out of Mexico, what pathway do you suppose they will travel? Follow this key lesson as you track the migration during the next three months.
Mass Migration in California--But Were They Monarch Butterflies?
All of a sudden on Tuesday, migration reports began to appear like a rash on the map on the edge of the Mojave Desert, near San Bernardino, California. One person saw a "massive swarm of monarchs" and "about ten butterflies bumped into me," said a boy. Here's how others described what they saw:
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But were they monarch butterflies? |
What Does the California Expert Think?
We contacted Walt Sakai, Professor of Biology at Santa Monica College, to ask his opinion. He has been conducting research on monarch butterflies in California for nearly 20 years. Pay attention to the way he analyzes the situation. What words show that he remains opened-minded and skeptical at the same time? What evidence does he say he needs to confirm the reports?
What Does Monarch Migration Look Like in the Spring?
Next we asked Dr. Calvert to describe monarch migration. "It's not dramatic, actually, what you see," he responded. He went on to describe the migration in his state of Texas, the best state for watching the migration. "You never see too many at once. You may see one or two an hour. That would be a good spring migration. Sometimes along the coast you can see maybe ten or twenty at once, but that would be during a strong migration."
Last spring, hundreds of people reported migrating monarchs to Journey North. You can read their comments at the link below. How would you describe the nature of monarch migration in the springtime, according to these accounts?
Painted Lady Butterflies: An "Outbreak and Migrate" Life History
We became suspicious, so did some research about the migration of a monarch look-alike, the Painted Lady butterfly. Their migrations do not occur every year but can be spectacular after heavy rains in the deserts. The rains produce unusually lush vegetation, which allows unusually large numbers of Painted Lady caterpillars to survive. The caterpillars become so numerous they strip the vegetation. When they emerge later as adult butterflies, they leave in massive flights in search of fresh vegetation. For more information see this excellent site:
What do YOU Think? Challenge Question #7
Finally, we'd like to know your opinion:
Challenge Question #7
"Do YOU think the massive migration in California this week was of monarch butterflies? Explain what you think happened, and give as much evidence as you can to support your explanation."
(To respond to this question, please follow the instructions below.)
Try This! Practice With Butterfly Identification
Here's a fun way to practice observation skills while you prepare to track monarch migration. Pull out your sketch pad and take a close look at these photos of a monarch, a painted lady, and other look-alike butterflies.
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| Monarch Danaus plexippus Photo Jim Gilbert |
Painted
Lady Vanessa cardui Photo Peter J. Bryant |
Monarch Winter Habitat: Assessment Suggestions
This season, we have been exploring the key components of the monarch’s winter habitat: food, water, shelter, and space. Now that the monarchs are leaving Mexico, here are assessment tools and strategies to document students’ grasp of habitat-related concepts.
How to Respond to Today's Monarch Challenge Question
1. Address an e-mail message to: jn-challenge-monarch@learner.org
2. In the Subject Line of your message write: Challenge Question #7
3. In the body of your message, answer the question above.
The Next Monarch Migration Update Will Be Posted on March 25, 2005
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