Monarch Migration Update: Oct. 6, 2011
Please Report
Your Sightings!

Monarchs are pouring into Texas now, and they're eating something surprising. Can you solve the mystery? Peak migration reports show monarchs moved in massive numbers this week. It's October. The monarchs must hurry before they're trapped by the cold! Explore how temperatures affect fall migration.

This Week's Update Includes:


Image of the Week

monarch butterfly roostTamara Lewis

Can you solve the mystery?

News: A Peak Week

High Counts
From the Atlantic Coast to Texas, it was a big week for migration. After several days of rain in the east, high pressure moved in, the sun came out, and so did the monarchs. The map of peak migration is filled with reports like these:

"We were at recess and counted 65 monarchs fluttering across the playground on their way south." Union Avenue School, Margate, NJ

"Monarchs flew south for migration over the building!" We thought it was a good idea to tell everyone about it." Leeds Avenue School, Pleasantville, NJ

Tagged Monarch Found!
A New Jersey teacher from JC Caruso School found quite a surprise when he captured a monarch in his backyard this week: "I realized it was one we released at my school 7 days earlier, 22 miles north of where we live."

Hugging the Coast
Monarchs travel down the Atlantic coast to avoid the open ocean. Habitat on the shore can be critical for monarchs, especially those that were blown out to sea:

"While on the beach they were coming off the ocean in groups...continually! Some were so tired they were seen resting on the beach. Others were flying in groups toward the dunes and heading for food and cover for the night." Long Beach Island, NJ

Denise Gibbs monitors migration on Virginia's Assateague Island. She estimates 5,000 monarchs were roosting there on Tuesday night. This is the largest report of the season outside of Texas. Migration was strong all day:

"The monarchs migrated down the beach in a continuous stream from 8:15am to 6:15pm. The average was about 600 per hour."

Why the Ohio River?
Spontaneously on Tuesday, people along the Ohio River reported a huge wave of migration. Why so many monarchs along a 50-mile stretch of the river?

"More monarch butterflies than have ever seen! They continue to pass by, even as I sit here typing this. More that 200 per hour. A continuous stream." Yorkville, OH

Funneling into Texas
All monarchs headed for Mexico must cross Texas, and the butterflies began to arrive in substantial numbers this week. Look at the map to see how far west many monarchs are:

"I just spoke to a rancher who has thousands roosting in pecan orchards near Valentine."

"Monarchs have invaded in mass! They are literally everywhere. Every flower patch has hoards hovering." Midland, TX

"The trees are dripping with monarchs. They are so thick in the air I can hear and feel the wing beats." Ft. Stockton, TX

Graph: Number of roosts reported as of September 14th each year

Graph: Number of roosts reported as of September 14th each year

Decorating a Tree
Linda Kemp

Discovering a Drink
Rendi Hahn

Graph: Number of roosts reported as of September 14th each year
Hugging the Coast

Graph: Number of roosts reported as of September 14th each year

Roosting in New Jersey
Paige Cunningham

Graph: Number of roosts reported as of September 14th each year

Nectaring in Arkansas
Carl Jeffers

Graph: Number of roosts reported as of September 14th each year

Coming Down at Sunset
Carl Jeffers

Graph: Number of roosts reported as of September 14th each year
Arriving in West Texas
Layla Battista

The monarch overwintering region in Mexico is at longitude 100 west.

So far west!

Seeing Monarchs?
Report Regularly!

Please report at least once a week. Tell us when and where monarchs are present.

Hello From Mexico: Hola Desde Mexico

No monarchs yet, the Romeros report from Angangueo.

"While we wait for the monarchs to arrive this fall, we are welcoming a change in our lives. Only a few weeks ago, Angangueo came back to life as a mining town..."

Estela, with her mother Lolita, and daughter Emilia.

Estela Romero reports from Angangueo

Slideshow: Too Cold to Fly?

Monarch butterflies are in a race against time during fall migration. They must leave the north before they're trapped by the cold. Monarchs are cold-blooded so, in order to fly, their flight muscles must be warm enough. Using the facts and photos in this slideshow, explore this essential question: How do temperatures affect fall monarch migration? See slideshow:

Tagging Monarchs: Tiny Tags, Big Discoveries


The Migration: Maps and Journal Page
Monarch Butterfly Migration Map: All Sightings, Fall 2011 Monarch Butterfly Migration Map: Fall Roosts, Fall 2011 Migration Questions: Week 2

All Sightings

(map | sightings)

Fall Roosts

(map | sightings | archives)

Seeing Monarchs? Please let us know!

The next Monarch Migration Update will be posted October 13, 2011.