Migration Update: February 26, 2009
Please Report
Winter Sightings! >>

Today's Report Includes:

Photo by Dr. Lincoln Brower, Sweet Briar College

How is a tree-trunk like a hot water bottle? >>

News from the Monarch's Winter Home in Mexico

Monarch butterflies east of the Rocky Mountains fly to Mexico. >>
They gather together on only twelve mountain top sites. Find them! >>
Field Report from Mexico from Dr Lincoln Brower >>

Dr. Lincoln Brower just returned from the monarch overwintering sites in Mexico:

"I wanted to check up on the colonies to see how they are doing," he said. "And also to take some close-up photographs of the beautiful arrangements of the monarch clustering on tree trunks. We just finished up a (scientific) paper that shows that the tree trunks are like a hot water bottle."

Read and listen to our interview with Dr. Brower and see his remarkable photos, including one of a giant-sized tree trunk with 5 people standing inside it. He says monarchs that cluster on tree trunks have two advantages. Can you find them? Large trees offer greater protection for the monarchs, said Brower. "Here is another very, very strong argument for conserving an old-growth forest and promoting the return of these old big trees."


Photo by Dr. Lincoln Brower, Sweet Briar College

Five people fit inside the remnant trunk of this giant-sized tree. The monarch's forest had huge trees many years ago and they offered the butterflies more protection.

Signs of Colony Break-up Signal Spring by Dr. Bill Calvert >>

Also reporting from the sanctuaries this week is Dr. Bill Calvert who witnessed a clear sign that spring migration will soon begin: At the Sierra Chincua sanctuary, the colony has expanded and is breaking up. The activity level of the butterflies at the El Rosario sanctuary was dazzling, he said:

"The first indications of the delights to come were the tens of thousands of butterflies swarming over the llano, and thousands nectaring and drinking from mudflats, seeps, and open waters," said Dr. Calvert. "The butterflies at Rosario were extremely active and dazzled all present with their spirited exuberance."

Dr. Bill Calvert

Journal: How Does the Forest Protect Monarch Butterflies? Think by Analogy

Dr. Lincoln Brower says the monarch's forest is like an umbrella and a blanket, and the tree trunks act like hot water bottles. Analogies help us understand new things because they draw upon our past experiences. Try some! Use analogies to describe how the forest protects monarch butterflies.

Journal Page

Ask the Monarch Butterfly Expert: Now Open! >>

Special thanks to Dr. Karen Oberhauser for sharing her time and expertise again this year to answer readers' questions. Do you have questions that only an expert can answer? Beginning today, you have two weeks to prepare and submit your questions to Dr. Oberhauser. What are you wondering about?

Dr. Karen Oberhauser

Report Your Sightings: Seeing Winter Monarchs or Milkweed?

All monarchs do not go to Mexico. Please help us document where monarchs are located this winter, and whether milkweed is available.

  • Please report your sightings. >>



Links: Monarch Butterfly Resources to Explore
More Monarch Lessons and Teaching Ideas!

The Next Monarch Migration Update Will Be Posted on March 3, 2009.