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Monarch Butterfly Migration Update: September 6, 2001
Today's Report Includes:
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Highlights From Along the Migration Trail
- First Sightings from the Northeast
- Migration Through Midwest Peaks in Iowa
- The Historic Importance of the Prairie Ecosystem to Monarchs
- A Field Trip to the Prairie with Dr. Lincoln Brower
- How is a Migration Like a Vacation?
- Challenge Question #3: Why Does the Chrysalis Twist and Turn?
- From Caterpillar to Chrysalis: Video Clip of Monarch Metamorphosis
- Reminder: Challenge Questions #1 and #2
Highlights From Along the Migration Trail
- Link to This Week's Migration Data (for classroom mapping.)
First Sightings from the Northeast
Apparently lagging behind the migration's early start in the Midwest, monarchs in the Northeast now appear to be
on the move.
- "A series of cold fronts seems to have triggered the southward movement of monarchs in Ontario," reports Don Davis from Toronto. "Lots of monarchs are heading in a south-westerly direction, soaring high above buildings in the towns and villages located along the north shore of Lake Ontario."
- In Vermont, Ms. Gannon of East Montpelier Elementary noted a sudden change: "I have been counting the number of monarchs I have seen. In August I saw 20 monarch butterflies. Over the weekend they must have started migrating. I saw 25 butterflies in two days!"
- "Looks like the migration has started here in Woodbridge, N.J.," reports Mr. James Kupcho. " I observed 35 monarchs in a 2 1/2 hour period on September 4th."
Migration Through Midwest Peaks in Iowa
Traveling southward through the Midwest, the peak migration appears now to be moving across Iowa:
- Near Des Moines, Iowa, Harding Middle School reports hundreds of monarchs resting in pine trees on the Sears farm north of Huxley on August 28th.
- The fifth and 6th grade students at Iowa's Cresco Elementary are surprised to see the monarchs migrating already when compared to last year's data. "The 'Monarch Tree' at the town park had hoards of them over the past days and last night (08/30/01) there weren't as many," they observed.
- "Monarchs have been thick in the trees since August 25," reports Stacey Newbrough from Tripoli, IA "Last night (8/30/01) we tagged 133 in one and one half hours . . . so many more roosting high in the trees. Awesome sight! We tag for Monarch Watch. In the past week we have tagged 450 butterflies. The past 5 years we have not begun to tag until Labor Day weekend."
- "Another great day for monarch watching. The highlight came in the afternoon--from 4:15 p.m. to 5:15 p.m.--when 302 migrating monarchs were counted in the air during the single hour," reported Professor Woodward of Drake University on September 3rd. "The wind was blowing from the northeast, and the monarchs were essentially riding the wind--especially when they were flying or floating at 1,000 feet or above."
How do Iowa's current monarch migration patterns compare with those of previous years? Professor Woodward's has keep regular field reports during 1997, 1998, 1999, and 2000. You can read his comments and field observations online:
- Professor Woodward's Monarch Migration Journal for Central Iowa
The Historic Importance of the Prairie Ecosystem to Monarchs
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Liatris is a favorite nectar source for monarchs migrating on the prairie Click here for video clip (.mpg file 5,368 Kb) |
And the Midwestern prairie ecosystem was their historic center of breeding, notes Dr. Lincoln Brower. The original prairie covered some 433 million acres and was host to a great diversity of milkweed--about 22 Asclepias (milkweed) species. Ironically, monarchs were probably never very abundant to the east of the prairie, believes Brower. However, plowing of the prairies, together with clearing of the eastern forests, promoted the growth of the common milkweed, Asclepias syriaca, and probably extended the center of the breeding eastward.
A Field Trip to the Prairie with Dr. Lincoln Brower
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Dr. Brower |
"I've only been in a prairie situation like this when monarchs were migrating twice in my life and it's so beautiful to see these absolutely mint condition butterflies. They've just hatched out, they're probably 2-3 days old. Their wings are actually almost shining in their brilliance. And I always say to myself, what a beautiful animal this is. I've been studying them now since 1955, that's what, 46 years? And, you know you might think somebody that has studied the same thing for 46 years would be sick of it, but I just never get sick of these creatures. They're just so elegant and beautiful!"
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Dr. Brower on Schaefer prairie, where 245 native plant species can be found. |
Sneaking up on a nectaring monarch |
"If you try to catch a butterfly between your thumb and forefinger in the summertime you'll have a very, very hard time catching it. But they are so intently nectaring [during migration] that you can actually, if you're really careful, sneak up with your thumb and forefinger and just grab one and then take it in your hand and gently look at it and see whether it's a male or female.
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Comparing male and female monarchs |
Note larger abdomen of monarch on the left |
"You can look--if they've had a good feed their stomachs will actually be fat. (See photo.) They feed on
that [nectar], and the nectar has sugar in it. They convert that sugar into fat and that fat is the energy store
that they use to fly down to Texas and then on into Mexico. (That sure beats $2 per gallon gasoline.) Ha, ha, ha...It
sure does!"
How is a Migration Like a Vacation?
When you go on a trip, a lot of preparation takes place. How is a human vacation different from an animal migration? (For example, have YOU ever traveled without a suitcase?)
As you begin the monarch migration season, compare and contrast the purpose of travel, the preparations required, and the consequences of any mistakes. You're sure to appreciate the monarch's remarkable journey even more after comparing their abilities to our own.
Challenge Question #3: Why Does the Chrysalis Twist and Turn?
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From Caterpillar to Chrysalis |
Challenge Question #3:
"Why does the monarch twist and turn so vigorously as the chrysalis forms?"
Reminder: Challenge Questions #1 and #2
We're waiting for students to send their thoughts about Challenge Questions #1 and #2. In next week's update, we'll come back to these questions. So please take a minute and send us your response. We'd love to feature your ideas in next week's update:
Challenge Question #1:
"When do you predict the first monarchs will arrive at the Mexican sanctuaries this year?"
Challenge Question #2:
"Who saw the most monarchs? (See last week's update.) In your answer, use the same units to compare the number of monarchs (either monarchs/hour or monarchs/minute). Arrange the observations in order, from the observer who saw the most to fewest monarchs."
How to Respond to Today's Monarch Challenge Questions:
IMPORTANT: Please answer ONLY ONE question in each e-mail message!
1. Address an e-mail message to: jn-challenge-monarch@learner.org
2. In the Subject Line of each message write: Challenge Question #1 (#2 or #3)
3. In the body of the message, answer ONE of the questions above.
The Next Monarch Migration Update Will Be Posted on September 13, 2001.
Copyright 2001 Journey North. All Rights Reserved.
Please send all questions, comments, and suggestions to our feedback form
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