This fall’s extraordinary migration added a remarkable chapter this week. Monarchs appeared in unexpected places and in unprecedented numbers.

The largest gathering of the season, perhaps as many as 100,000 butterflies, is now resting and refueling in Arkansas.

In New Orleans, hundreds were migrating along the longest bridge in the world rather than travel across the open water.

Such careful water-avoiding behavior makes one wonder: how did the monarchs that were reported this week in the Bahamas and England get there?

"Por fin en México!!!" came the word from Rocio Treviño as this report was about to go out the door. Monarchs are crossing the border at the rate of 100-120 per hour in Acuña, Coahuila.

Here's the news:

Crossing Arkansas

Photo: David Moyers, Ph. D.
Ashley County Ledger

10/7/06 Wilmot, AR
Dr. Jim Edson turned his car toward Wilmot when he heard this news: monarchs were as thick as 100 per square meter on farm conservation land there!

"I don't know how to estimate the numbers, but the tree line is about 0.5 miles long and all of the trees were full of monarchs. I haven't seen anything like it except in Mexico. There could have been anywhere from 10,000 to 100,000 butterflies.“

Look at the migration map. Where do you suppose the monarchs now in Arkansas came from?

Crossing the bridge

Image: NASA Earth Observatory

10/7/06 New Orleans, LA
Monarchs migrate along the 24-mile bridge across Lake Pontchartrain into New Orleans every fall.

"I travel on Highway 11 each morning to work," says Sally Novatney. "Monarchs follow the bridge road on their way south rather than fly over the water. I drive as slowly as I dare so the wind current doesn't bring them into my car."

Can you see the city and the tiny cars when you click on the image?

Crossing the Caribbean?

10/5/06 Marsh Harbour, Abaco
10/9/06 Nassau, Grand Bahama
Monarchs were sighted on two separate Bahaman Islands this week! Both observers said they rarely see monarchs. Where do you think these monarchs came from?

Tagged monarch have been recovered in the Caribbean. One from Ontario landed in Cuba, and one from New Jersey in the Bahamas. However, the Bahamas also have a monarch population of their own, says Dr. Bill Calvert. Perhaps the monarchs that are blown off course become founders of new populations, he speculates.

A monarch butterfly was sighted across the Atlantic Ocean on Monday! It was spotted on a small island off the West Coast of England (49.93 N, -6.30 W). Read the observer's comments and look at these maps (large and close-up).

Do you think a monarch butterfly could fly across the ocean? Where do you think this monarch came from? Scientists wonder about these questions, and they have posed several theories. Before you read their ideas, think about these questions yourself:

• How would you explain the appearance of a monarch butterfly in England? Where do you think the monarch came from? Now read on >>

The suggestions in this guide are provided to help teachers integrate Journey North's real-time program in the classroom.

• Link to Teachers' Guide for October 13, 2006