Monarch Migration Update: Oct. 20, 2011
Please Report
Your Sightings!

Northern Mexico's skies were "painted orange and black" this week as monarchs crossed in the thousands. Mexico's geography is funneling the migration into rivers of butterflies. Highway signs warn to drive carefully. Monarch butterflies are mariposas monarcas now!

This Week's Update Includes:

Image of the Week
Road sign in Mexico along monarch migration route.

Be Careful!
Rocio Trevino

News: Cruising Across Mexico

Only 400 Miles to Fly!
"They're here! A migration like this I haven't seen in a decade," Rocio Trevino reported on Wednesday from her home in the northern state of Coahulia. "All day yesterday saw thousands of monarch throughout the city of Saltillo. Before dark they were flying low, looking to spend the night. This morning, though temperatures barely reached 16°C at 7 am, the butterflies began to rise from their perches. From 8 to 10:30 am they were on their way south, aided by the north wind blowing and announcing the entrance of cold front No. 7. Today, butterflies gave a beautiful performance in the entire metropolitan area of Monterrey."

Monarchs are Mariposas Now
Now that they've entered Mexico, monarch butterflies are mariposas monarcas. Read today's sightings. Can you can find matching phrases in Spanish for these?

  • flying at the height of the rooftops
  • an average of 5 to 10 per minute
  • their bright colors make them so beautiful
  • it was wonderful to watch them fly!

Which Mexican States?
Learn the names of the Mexican states and label them on this map. Monarchs have been reported from three Mexican states so far. Can you find them?

Following the Mountain Chain
As the butterflies enter Mexico, two geographic features compress their flight-path. "This funneling is due to the Gulf of Mexico and Mexico's Sierra Madre Oriental mountains," says Dr. Bill Calvert. "The butterflies seem to follow the mountain chain."

Getting a Lift
The Sierra Madre Oriental range stretches for 600 miles across Mexico to the southeast. As easterly winds blow, the air rises over the east-facing mountain slopes. Monarchs use the mountains for a free lift southward.

Blown Off Course in Michigan
Without the help of the wind, monarchs could not migate to Mexico. However, the wind can also be dangerous. Observers shared a sad story from Lake Michigan this week, where gale-force winds produced 18-foot waves and monarchs got caught in the storm.

Students Still Seeing Monarchs!
Give a shout of thanks to students who are helping to track the migration. Here are some who reported migrating monarchs this week, from north to south:

  • Illinois: "The third and fourth graders were outside at recess after mailing their symbolic butterflies to Mexico. They were very excited to see 5 monarch butterflies flying and being moved by the wind for 10 minutes." Chicago, IL
  • Kentucky: "We saw about 1 monarch a day this week." Cub Run, KY
  • North Carolina: "Our children playing on the playground saw 3 flying about." Winston-Salem
  • Alabama: "My 3rd and 4th graders were professional monarch butterfly hunters today. We saw a total of 11 monarchs and caught 9 of them. We identified 7 males and 2 females." Billingsley
  • Florida: "We saw 3 monarchs in our butterfly garden." Tampa
  • Oklahoma: "Mrs. Jamison's 4th grade class observed 7 monarchs in our butterfly garden. We caught and tagged a male and a female." Durant
  • Texas: "Besides the 102 counted during our 30-minute recess this morning, we are observing a monarch fly by our second-story window every 60 - 90 seconds! Beautiful!" Austin

Monarch migration map: Higlights of the Week
Only 400 Miles to Fly!

Frent frio no. 7
Frente Frio No. 7
Cold Front Number 7

Monarch butterfly migration, Long Island, New YorkMariposa Monarca
Monarch Butterfly
Lisa Barker

Peak migration in Cape May, NJRacimo de mariposas
Cluster of butterflies
Pat Piaschyk

Monarch butterfly on beach along Lake Michigan after wind storm.Blown Off Course
Jennifer Anderson

Monarch butterfly at school garden.
Library Visit
Dierdre Johnson


Hello From Mexico: Hola Desde Mexico

"All around we sense the monarchs butterflies should arrive to our region soon. Meanwhile, our children are in a rush to attend school, and townspeople are preparing to greet monarchs—and tourists!" This week, Estela gives us a glimpse of school-life. How does your school year compare to the children's in Angangeuo?

School life in Angangueo, Mexico

School-life in Angangueo

The Migration: Maps and Journal Page
Monarch Butterfly Migration Map: All Sightings, Fall 2011 Monarch Butterfly Migration Map: Fall Roosts, Fall 2011 Map of Mexico: Which states do monarch butterflies cross during migration?

All Sightings

(map | sightings)

Fall Roosts

(map | sightings | archives)

Seeing Monarchs? Please let us know!

The next Monarch Migration Update will be posted October 27, 2011.