Journey North Monarch Butterfly Spring 2006

Monarch Butterfly Migration Update: February 24, 2006

Today's Report Includes:

Meet Dr. Bill Calvert: Our Telephone Tour Guide
Field Notes from Mexico from Dr. Bill Calvert
Food, Water, Shelter, and Space: A Look at WATER
Mexico's Wet and Dry Seasons: Dr. Brower’s Precipitation Graph
Where Do Monarchs Get Water? Challenge Question #4
People and Water: Life in the Monarch Butterfly Sanctuary Region
Where Did They Eat? Discussion of Challenge Question #3
Do Monarchs Eat in Winter? A Good Scientist Keeps an Open Mind!
Is Nectar Important? More Research and Questions

Meet Dr. Bill Calvert: Our Telephone Tour Guide
Dr. Bill Calvert was one of the first biologists to study the monarchs at their over-wintering sites in Mexico. For the next three weeks he will be our special telephone tour guide. But first...

Meet Dr. Bill Calvert

Field Notes from Mexico from Dr. Bill Calvert
This week's visit was "better than it gets," he said. "A river of monarchs streaming down from the mountains greeted us. We and our horses treaded through this sea of butterflies..."

Why were the butterflies flying this way? You can read and hear Dr. Calvert's news and observations.

Food, Water, Shelter, and Space: A Look at WATER

This season, we are exploring the monarch's overwintering habitat. How do monarchs satisfy their need for water? Let's begin with a look at Mexico's wet and dry seasons. What do you suppose these seasons mean for monarchs?

Mexico's Wet and Dry Seasons: Dr. Brower’s Precipitation Graph

This graph is adapted from Dr. Lincoln Brower's research. It shows rainfall in the sanctuary region for every month of the year. Look carefully at the graph and describe what you see.

How have things changed since the monarchs arrived in November? (Click graph to enlarge.)

Where Do Monarchs Get Water? Challenge Question #4
It is now the end of February. The dry season has been underway for four months as you can see from Dr. Brower's graph. So...

Challenge Question #4
"Where do you think monarchs get the water they need to survive the dry season in Mexico? How many sources of water can you imagine?" (In next week's report you will find ways that are sure to surprise you!)

To respond to this Challenge Question, please follow these instructions.

People and Water: Life in the Monarch Butterfly Sanctuary Region
"Imagine carrying 800 liters of water every day to your house from a well a half a mile away…by foot! In the dry season, this is daily work for me and my family," begins Maria Louise Mondragon. She and her family own land in the Sierra Chincua Sanctuary and they live in the valley below.

Here is their story in both English and Spanish:

Recursos de Agua para las Familias de la Región del Santuario (Español)
Water Resources for Families in Sanctuary Region (English)

Where Did They Eat? Discussion of Challenge Question #3	Good food as a caterpillar prepares a monarch for survival in Mexico.
Last week's Challenge Question #3 asked, "If it’s true that monarchs do not eat while they are in Mexico, then when and where DID they get the food energy that they are burning now?" "Where they used to live and on their journey," concluded Mrs. Busher's 4th grade class in Wirtz, VA.
Isn't that amazing? The nectar a monarch ate last fall as an adult--and even the milkweed it ate as a caterpillar--can be critical to its survival in Mexico. Running out of fat is a common cause of death. "Monarchs that you see littering the ground have usually starved to death," says Dr. Calvert.

Do Monarchs Eat in Winter? A Good Scientist Keeps an Open Mind!
We hope you noticed the "if" in our question: "If it’s true that monarchs do not eat...."

"My caution to you is to not picture anything as 100% true or false," wrote Carol Cullar, a Texas naturalist and experienced monarch butterfly observer. She makes an important point: While it may be true that "a" monarch "can" go without eating all winter, that does not mean that "all" monarchs "never" eat!

Carol Cullar's Observations in Mexico's Monarch Sanctuaries

Is Nectar Important? More Research and Questions
Scientists have certainly noticed monarchs drinking nectar from flowers and they have studied the question further. Read carefully and notice how they continually question their own and others' assumptions, data, methods, and results. Then try it yourself!

Dr. Brower: Monarchs that are visiting flowers are starving to death. Those butterflies are "running out of gas."
Dr. Calvert: "As far as I'm concerned, the question about whether nectaring is important is unresolved at this time."
And You? Can you see other ways to look at the question?


Photos Courtesy of Dr. Lincoln Brower, Sweet Briar College

The Next Monarch Migration Update Will Be Posted on March 3, 2006