Monarch Migration Update: Oct. 13, 2011
Please Report
Your Sightings!

The migration is entering Mexico now, and warm fall temperatures in the north are giving monarchs more time to fly. How much farther must the monarchs travel? Compare distances from two flyways. Also, explore the food chain mystery. How are monarchs and aphids connected?

This Week's Update Includes:


Image of the Week

Monarch butterfly nectaring on bank of Rio Grande River.

Picture Proof!
Paul Nava

News: Now Entering Mexico

Crossing the Border
Señora Rocío Treviño was waiting in line at the border when she saw it: "A monarch crossing without a passport!" she exclaimed. Rocio coordinates Mexico's migration-tracking program called Correo Real. Her network of observers share sightings from northern Mexico. Get ready to practice your Spanish! Here's a report from Monterrey. How many monarchs did the observer see, and how high were the butterflies flying?

"Están pasando monarcas hacia el sur, en cantidades de aproximadamente 10 por minuto y volando a una altura no mayor a los 50 metros." 12 de octubre: Monterrey, Nuevo Leon

First Roost in New Mexico!
A surprising roost of 100 monarchs was reported in southern New Mexico. This is our first roost report from that state and, at longitude 106W, it's very far west! Look at the roost map and find the overwintering sites at longitude 100W. Why are the monarchs so far west?

Research in Texas
"Monarch expert Dr. Lincoln Brower is currently in Texas researching whether the Texas drought is affecting the monarchs," says Mike Quinn of Texas Monarch Watch, who joined Brower and others in the field Tuesday. "He collected monarchs to measure their lipid content during Texas' historic drought. Nearly every monarch examined appeared to be under weight. They should be putting on significant mass at this time."

Atlantic Coast
Monarchs continued to flow down the Atlantic coast this week. On Staten Island, NY, an observer saw 211 in 2 hours. A video clip from Cape May, NJ, shows another peak day as Paige Cunningham describes:

"The monarchs came sailing into town today. The goldenrod was covered and, anytime you looked in the air, you'd see them at all levels. I stood on a dune cross-over and had dragonflies and monarchs gliding past me for hours!"

Warm Fall, Late Sightings
Temperatures across the north have been unusually warm. With an extended growing season, late-season monarchs have had time to complete the life cycle. Monarchs are still being seen, and often in large numbers:

"I saw about 100 monarchs leaving New Hampshire's seacoast today in about an hour of continuous flow. The next morning, I saw lots more warming up and flying." Hampton Beach, New Hampshire: October 9

On the western shore of Lake Huron in Michigan, Frank Apsey reports: "I observed 250 monarchs flying south over the beach between 1:30 and 4:30 pm. Some were almost red in color. As they stopped to nectar, I estimated that there was 1 male per 12 females."

How Many Miles to Fly?
According to recent reports of peak migration, large numbers of monarchs are concentrated in two areas right now. In the central flyway, most are are in Texas. In the eastern flyway, most are along the Atlantic coast.

  • How much farther must the monarchs in each flyway travel? In this week's journal page, use Google maps to measure and compare distances.


Rocio Trevino, Correo Real

Reporting from Mexico

Roost in New Mexico!

Roost in New Mexico!
Bob Barber

Dr. Lincoln Brower studying effect of drought in Texas.
Research in Texas
Mike Quinn, Texas Monarch Watch

Peak migration in Cape May, NJ
Another Peak Day
Paige Cunningham

Monarch migration has entered Mexico!
Warm Fall, Late Sightings
Denise Brown


Seeing Monarchs?
Report Regularly!

Tell us when and where monarchs are present.

Please report at least once a week.

Hello From Mexico: Hola Desde Mexico

"It's impossible to imagine a monarch butterfly coming here right now!" Estela reports this week. "We've had cold, wet, cloudy days due to the influence of the last two hurricanes that hit Mexico's Pacific Coast." Estela tells how students spend their afternoons, and the role Internet plays in homework.

Estela, with her mother Lolita, and daughter Emilia.

Estela Romero reports from Angangueo

Mystery Solved: How Can Monarchs Feed in Pecan Trees?

Mrs. Greenfield's 4th grade students were among those who solved the food chain mystery. They wrote from R. F. Patterson Elementary in Texas:

"Our hypothesis is that the aphids are excreting honeydew drops onto the leaves. Honeydew drops are made of sugar and the monarchs like to sip anything with sugar in it. They need the sugar to get the energy to fly to Mexico."

Mrs. Bushers' 3rd graders in Viginia added a sentiment most people share:

"We think that is pretty gross."

Follow the food chain to see how energy reaches the monarch, from sunlight to secreted honeydew.



Monarch butterfly drinking honeydew

Eating Honeydew
Ethan McJames

Monarch butterflies and aphid honeydew

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 20, 2011.