Monarch Migration Update: Sept. 30, 2010
Please Report
Your Sightings!

With north winds at last, "bursts of butterflies" advanced down the Central Flyway. In the east, monarchs traveled along the Appalachian Mountain ridges where rising air currents carried them aloft. Monarchs are creatures of the air. How much do they weigh and how does wind affect them?

This Week's Update Includes:


Image of the Week
Monarch in the Bahamas: Where did they come from?
Where did the monarchs in the Bahamas come from?

News: Monumental Migration...Continued!

After last week's monumental migration along the Atlantic Coast, spectacular sightings were reported inland, along the Appalachian Mountains:

September 22: Blue Ridge Parkway, Virginia
"If a wave of monarchs is moving down the Blue Ridge Parkway, the crest of the wave is currently close to Roanoke, Virginia, according to my observations. And there are SO many in the crest! You could not look up into the sky without seeing many, many monarchs drifting on the wind. They were up high, down low, everywhere."

September 25: Mahogony Rock, North Carolina
"We stopped at Mahogany Rock Overlook where the annual hawk count was going on and learned that one of the counters had recorded over 300 Monarchs flying over by around 3:30."

The Appalachian Mountains: A Free Lift
Look at the ridges of the Appalachian Mountain landscape. When the wind is right, the Appalachians provide ridge lift for migrating monarch butterflies, as well as hawks, dragonflies and other birds and insects. Monarchs can use ridge lift to gain altitude, and then soar effortlessly along the Appalachian ridges. (See ridge lift graphic.)

Central Flyway
North winds blew and monarchs sailed southward to the delight of observers in Kansas, Missouri, Kentucky, Oklahoma and others. Here are some of the observations:

September 24: Bonner Springs, Kansas
"Observed approximately 100 in an hour heading SW today. We had about a 10 knot wind out of the N that seemed to be helping them move."

September 24: Kansas City, Missouri
"A wonderful day for Monarchs! Wind finally came from the north and with it came the Monarchs! In 4 hours I observed 471 Monarchs. Most came after 2:00 pm. It was fun to see hourly "bursts" of butterflies as they came in groups."

September 28: Hammon, Oklahoma
"Our third grade class observed and tallied the number of monarch butterflies migrating today. During a 30-minute observation time, the maximum number of monarchs a student counted was 570. The minimum was 100. The median number of monarchs observed was 330 monarchs."

Air flow from the north is predicted for at least three days, through Saturday. Keep an eye on the map for some excitement as the monarchs funnel their way toward Texas as beyond!

Ridge Lift: The Appalachian Mountains provide 'ridge lift' for migrating monarch butterflies.

Ridge Lift
When the wind hits the ridge, the air rises.
Glider pilots can use ridge lift to stay aloft for hours.
A Free Lift
Glider pilots can use ridge lift to stay aloft for hours, without an engine or fuel!
Ridges of the Appalachian Mountains
Ridges of the Appalachian Mountains
When the wind is right, the Appalachian Mountains provide ridge lift for migrating monarch butterflies.
Research Question: How does the wind affect light-weight monarchs?

"Monarchs are all about flight. They are paired with the air," says naturalist and pilot Carol Cullar.

Monarchs can fly with the wind. They can soar effortlessly along a mountain ridge, or float upward in a rising column of air. Strong winds can carry monarchs in the wrong direction, however, or blow them out to sea. Try to imagine the role wind plays in the daily life of a light-weight monarch butterfly!

Find Out:

  • How many monarchs in a piece of paper? Assume the average monarch butterfly weighs 500 mg. How many could you cut from one sheet of paper?
  • What can you find that weighs the same as a monarch? Does a monarch weigh more than a leaf or a feather?
  • A monarch tag weighs 10 mg. That's about 2% of a monarch's body weight. What weighs 2% of your body weight? What would it be like to carry something that heavy?
  • What happens to a paper butterfly in different wind conditions? Go outside and observe. Use the Beaufort Wind Scale to describe the strength of the wind.

The Beaufort Wind Scale

The Beaufort Wind Scale How strong is the wind when leaves rustle, trees toss, or dust flies?


Hola Desde Mexico: News from Angangueo

Dear Journey North friends,
As we wait for the monarchs to arrive, we would like to tell you a bit about the geologic origins of our region, and the golden times mining brought to our town and communities several decades ago. In the coming weeks, we will continue to show you aspects of our history through photos and visits to historic sites.



Students share drawing of lava and mountain formation

Students of José María Morelos¨ school in Angangueo show a hand-made illustration of our geologic history.

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 7, 2010.