Monarch Butterfly Monarch Butterfly
Today's News Spring's Journey North Report Your Sightings How to Use Journey North Search Journey North

Monarch Butterfly Migration Update: February 10, 2006

Today's Report Includes:


Exploring Monarch Winter Habitat:  Temperature, Temperature, Temperature
To understand monarch survival in Mexico, the role of temperature can't be overstated. Remember: Habitat is the place--and the conditions--where an organism's needs for life are met. Notice how temperature conditions affect the monarch's needs for food, water, shelter, and space. Today's examples are only the beginning! 

Brrrr…It Can Be Cold in Mexico!
Most people assume the monarchs fly to Mexico to spend the winter in a place that is warm. Were you surprised last week to see pictures of people wearing hats and mittens there? Why is it so cold? After all, this is subtropical Mexico.


Temperature and Elevation
The Monarchs are Nearly Two Miles High!

The monarchs form their winter colonies at very high elevations. They select sites at or above 10,000 feet. Temperatures can be very cold that high, especially at night. There are only 12 monarch mountains known. Three of the twelve are shown on this NASA image. Can you find them? Notice how the monarch's mountains rise like islands above the surrounding land. (This picture shows how it looks when you're there.) To understand the importance of elevation, let's check today's temperatures in places near the monarch sanctuaries, but at lower elevations, and see how they compare.

Can you find the three sanctuaries?

See this image.


Temperature and Time of Year
What Does This Graph Mean for Monarchs?

This graph shows the average low temperatures for each month of the year in the monarch sanctuaries. It’s mid-February now. What have the monarchs experienced since they arrived in November? How are things about to change? Look at the graph carefully and write a paragraph to describe it.


Temperature and Survival
A Balancing Act
Temperature conditions in the sanctuaries are key to monarch survival. If temperatures are too cold the butterflies will freeze to death. If temperatures are too warm the butterflies will burn their stored fat too quickly and starve to death. Wait, does this make sense to you?

Challenge Question #2
"People burn more energy in cold temperatures, trying to keep warm. Can you explain why monarchs burn less energy in cold temperatures?"

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

Discussion of Challenge Question #1: What Do Two Pictures Say?
Last week, just two pictures from the monarch sanctuaries revealed many clues about the climate there. Students from Florida, Vermont, and New Hampshire answered this challenge.
Here are the students' observations, as well as the inferences they were able to make.

What Do Two Pictures Say?

Discussion of
Challenge Question #1

The Next Monarch Migration Update Will Be Posted on February 17, 2006


Copyright 2006 Journey North. All Rights Reserved.
Please send all questions, comments, and suggestions to our feedback form

Annenberg Web SiteToday's News Spring's Journey North Report Your Sightings How to Use Journey North Search Journey North Journey North Home Page