Monarch Migration Update: April 27, 1999

Today's Report Includes:

News from the Migration Trail
According to observations reported this week, the monarchs did not make a big surge northward. However, they are appearing in greater numbers where they've already been seen. Your map should still show the migration front at about 40 N latitude.

Worn and Tattered At the End of Their Journey
Robert Annette's observations yesterday in Hampton, VA suggest some monarchs from Mexico are still alive--and have traveled some 2,300 miles:

"Observed two female Monarch Butterflies in my yard at 4:30 pm. Both appeared drab in color. Assume they have made a long trip. Laid an estimated 20 to 30 eggs on Common Milkweed I have in the garden. Sighting lasted for 20 to 30 minutes. They were having a difficult time as the wind was 10 to 20 mph. Some eggs were laid on top of the leaves. Plants are only one foot tall at this time, but growing quickly." (ra1645@aol.com)

Have you ever wondered how monarchs find milkweed? After all, how long would it take you to find the nearest milkweed plant?

Challenge Question #31
"How do monarchs find milkweed? What senses do they use? (If you have an interesting example of a monarch finding milkweed, please share your story!)

How Long Have These Monarchs Been Alive?
Discussion of Challenge Question #29

A long, long time, we realized last week! So we asked you to consider exactly how long it has been since these monarchs emerged. As students at Griswold Middle School in Rocky Hill, CT show, these monarchs' days are numbered:

"Monarchs born in Maine on August 20th would be 243 days (8 months) old as of April 20th, and monarchs born in Texas on October 20 would be 182 days (6 months) old as of April 20, 1999." (northgms@aol.com)
The Final Days: Same for Males and Females?
With their lives quickly coming to an end, how will these butterflies pass their genes to the next generation? In your mind, carefully compare the needs of males and females:
• Make a list all the things a female monarch butterfly must do in order to reproduce.
• Then make a list of all the things a male butterfly must do.

As you make each list, look for similarities and differences between the two sexes. Then answer this question:

Challenge Question #32
"Based on their need to reproduce, how do you think the behavior of male and female monarchs might be different?"

Watch the Wings: First Spring Generation Soon to Appear
Based on observations reported earlier this spring, many new monarchs should be on the wing by the first of May. When you see a monarch, be sure to look carefully at the condition of its wings. Are they faded and tattered, suggesting a monarch from Mexico? Or are the wings fresh and bright, suggesting a monarch of the first spring generation? Please include this information when you submit your field report.

Monarchs and Hummingbirds Race for the Border
Both species are now traveling across eastern North America, and nectar is needed to fuel both migrations. We'd like to know your opinion:

Challenge Question #33
"Do you think a monarch or a ruby-throated hummingbird will reach Canada first? Why? (Use migration data from each species to support your answer. Also, consider the life cycles of each.)"

How to Respond to Today's Monarch Challenge Questions