Monarch Butterfly Update: April 21, 1998
Today's Report Includes:
Latest Migration News and Data
The information James notes about the condition of the butterfly is important: It helps us determine how far
from Mexico the over-wintering generation of monarchs has traveled this spring. To date, no observers have reported
monarchs with fresh, brightly colored wings. (This would indicate newly emerged butterflies, of the 1st spring
generation.) Thus, if you're wondering how far north the monarchs that winter in Mexico travel, look at your migration
map. It is the answer for spring, 1998--so far.
Analyzing Weather and Monarch Migration
Six of the 7 sightings reported between April 13th and 19th were from Kansas and Nebraska. What weather conditions last week may have brought so many butterflies into these Midwest states? Compare the sightings dates against the weather conditions shown in these weather maps and see if you notice any patterns:
Symbolic Migration Update
Thousands of Butterflies Land in the North
Although they had a later start, the 40,800 symbolic monarchs have now passed the real ones. Their migration from Mexico took only 12 hours. They left Mexico City at 5:13 last night and arrived in Minneapolis at 5:40 this morning! You can track their migration every step of the way on the UPS WWW site.
Thanks For the Lift!
On Saturday, volunteers will assemble at the Science Museum of Minnesota's Magnet School. There the butterflies will be prepared for the final leg of their migration. Remember, watch your mailbox:
Homecoming Set for Symbolic Monarchs: May 10, 1998
Wanted: Monarch Butterfly Sightings
...Beware of Imposters
As you search for the most wanted butterfly this spring, beware of an impostor! There's another butterfly out there that's disguised as a monarch. (Don't worry, it's not armed and dangerous to predators as monarchs are.) Viceroy butterflies look exactly like monarchs to the untrained observer. In fact, viceroys "mimic" monarchs in appearance, as a strategy against predation.
Here's how it works: As you know, monarch larvae eat milkweed. There is a white substance in the milkweed that contains a chemical which is toxic to many animals--but not to monarchs. This toxin carries over to the adult, and predators know to avoid eating monarch butterflies because of this poison. Because viceroys look so much like monarchs, they avoid being eaten too!
As we track the monarch butterfly migration each spring, we are always concerned about accurate identification. For example, how can we be sure people are not reporting the first viceroy they see? Pull out your field guide to butterflies and make sure you can tell the difference between monarchs and viceroys. Then place a call to your local nature center and see if they can help you answer these questions:
Challenge Question # 12
Discussion of Challenge Question #9
On April 7th we asked, "If we consider the peak of egg laying is now occurring in areas where monarchs have been spotted, what date would we expect to be the peak date for adults to emerge--and continue the journey northward?"
Reminder: Restore and Protect Monarch Habitat--At Home and in Mexico
Many of you are aware that Lincoln Brower, Karen Oberhauser and Elizabeth Donnelly recently established the Monarch Butterly Sanctuary Foundation (MBSF). The mission of this organization is to help protect monarch overwintering habitat in Mexico.
So that schools can help raise funds for this effort, arrangements have been made with the Community Butterfly Gardens Project. This project introduces butterfly gardening to families through "starter kits" for butterfly gardens, and some of the proceeds will be donated to the MBSF for conservation work in Mexico.
This is a wonderful opportunity to improve conditions for monarchs--in the U.S and Canada, and at the overwintering sites in Mexico as well.
How to Respond to Today's Challenge Question
1. Address an e-mail message to: firstname.lastname@example.org
2. In the Subject Line of your message write: Challenge Question # 12
3. In the body of the message, answer the question above.
The Next Monarch Butterfly Migration Update Will be Posted on April 28, 1998.
Copyright 1998 Journey North. All Rights Reserved.