Monarch Migration Update: Oct. 7, 2010
Please Report
Your Sightings!

The migration moved into Texas this week, and a strong wave hit the Gulf coast states. Scientists found one wayward butterfly at sea. What happens when butterflies are blown over the ocean, and how is coastal habitat critical for those lucky enough to return?

This Week's Update Includes:


Image of the Week
Scientists report monarch 120 miles out at sea.
Monarch found by scientists at sea!

News: Southern States Greet the Great Migration

North Carolina Students Catch a Wave
First grade students in Lincolntown, North Carolina witnessed a wave of monarchs as it moved along the eastern edge of the Blue Ridge Mountains on Friday:

"We stopped for about 4 minutes and counted at least 50 monarchs. Some were very high—just pin-points in the sky—and some were very near the earth. I have never seen a migration," wrote teacher Ms. Hargrove.

Spontaneous reports that day from neighboring towns indicate the butterfly swath covered an area at least 40 miles wide. Good catch, North Carolina kids!

Migration Hits Shores of Gulf Coast States
Another wave of migration occurred on Tuesday and Wednesday along the Gulf coast in Florida, Alabama, and Louisiana. We received our first-ever report of a roost in Alabama, where the monarchs were hanging leisurely on lovely Spanish moss. But all was not well:

"There are thousands of monarchs...The sight is magnificent! I have never seen anything like this. There are also a great number of dragonflies attacking them."

If monarchs contain poison that protects them from predators, how can dragonflies eat monarchs? (More...)

Monarchs Move into Texas
North winds blew for a week and the butterflies sailed into Texas. In just eight days 26 roosts have been reported, and several clusters contained "thousand and thousands butterflies."

Students saw monarchs from the playground in Ennis, and a teacher announced them to her class as they flew over Austin. "My fourth grade students saw 28 monarchs in the San Antonio area," reported Saint George Episcopal School on Wednesday.

Why so far west?
The monarch's overwintering region in Mexico is at longitude 100 West. Notice how far west of that line the roosts in Texas were this week. Let's pay attention to longitude 100 West and see where the monarchs go next!

An Outlier: Early Roost in Mexico?
What do you make of the early roost report in the Mexican state of Guanajuato? The observer reported 100 monarchs in a town that's only 100 miles from the overwintering region. He could not provide a picture because the butterflies stayed for only a day. An "outlier" is a data point that differs widely from the rest of the data. Outliers raise questions. They may indicate something is wrong with the data point and should be examined carefully.

More Monarchs on the Way!
Among the many monarchs still flying down from the north are those released this week by Ms. Turner's class at Turtle Creek Elementary. You can watch them fly! (See YouTube Video.)

Monarch butterflies roosting in Spanish Moss during fall migration along Alabama Gulf coast

Our first report of a roost in Alabama!
Dragonflies were preying on monarchs in Alabama.
Monarch butterflies coming to roost during fall migration in Colorado City, Texas
Monarchs fly over the Texas sky.
The monarch overwintering region in Mexico is at longitude 100 west.
Why so far west?
Nonfiction Reading: How Coastal Habitat Helps Monarchs

Monarchs on seaside goldenrod at dawn.

Photo: Denise Gibbs

Coastal habitat is important for monarchs as they move down the Atlantic Coast. The seaside goldenrod that grows on the dunes is the monarch's favorite fall nectaring plant. It's critical for butterflies that come ashore after being blown out to sea, says monarch expert Denise Gibbs. She has watched thin and exhausted butterflies return to shore on Virginia's Assateague Island:

"Monarchs are burning up their fat reserves every time they get blown out over the ocean and try to make it back to land," explains Denise. "That is why I return here every spring and fall to plant seaside goldenrod. I want to ensure that there will always be nectar for those exhausted monarchs just making landfall."

Hola Desde Mexico: Hello from Mexico

Dear Journey North friends,
I heard the surprising news that 100 monarchs were sighted only 200 kilometers from here, so I made my first visit to El Cerrito. El Cerrito is a hill above our town where the monarchs traditionally first appear.



Zamara monitoring the monarch's arrival on the graph.

Zamara is helping to monitor the monarch's arrival with this graph.

The Migration: Maps and Journal Page 
Map of All Monarch Butterfly Sightings: Fall 2010 Map of Monarch Butterfly Roosts: Fall 2010 Migration Journal Page

ALL Monarch


Fall Roosts


For Your Journal
This Week's Questions

Seeing Monarchs? Please let us know!

  • Report frequently—at least once a week—as long as monarchs are present.
  • Count monarchs: Tell us how many monarchs you see per hour (or minute).
  • To report your sightings, press here.
The next Monarch Migration Update will be posted on October 14, 2010.