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Monarch Butterfly

Monarch Migration Update: September 9, 1997

The Finish Line
Here's a view of the monarchs' destination, the Transvolcanic mountains of Central Mexico. One can't help but wonder, will this new generation of monarchs find the same mountains their great-grandparents left last spring? Click picture for a larger image.

" I live less than 50 feet from Lake Ontario, on the 5th floor of an apartment building. I have enjoyed watching the thousands of Monarchs fly past my balcony--I can almost touch the butterflies as they glide past me. It is amazing how high they climb. I would love to know how they are able to find their way to Mexico??.."
August 28, Burlington, Ontario, Canada
Jacqueline Rimmer (rimmer@worldchat.com)

The monarch migration takes place without a single sound--all the way to Mexico--but it creates a great stir of excitement in the hearts and voices of people who witness it. Over the next weeks, we'll forward highlights of this fall's migration, as reported from people along the monarchs' path. We begin with the first notes from the north, where the migration began toward the end of August. Just this morning news arrived from further south, announcing that a wave of butterflies had arrived in Nebraska.

How to Report Your Sightings
Please keep your eyes on the skies and report monarchs you see in your region. Also, let us know what you're doing to Unpave the Way for Monarchs! To report your monarch sightings or news about your monarch habitat project, simply press the owl button on the left and a Field Data Form will appear.

Highlights Along the Trail

August 24 Minnesota
"An estimated 20,000 monarchs were nectaring at this blooming alfalfa field. Surrounded by
Weather map showing conditions on August 28 at 6pm. Click map for a larger image.
Migrating monarchs rest in a Maple tree in Minnesota. The monarchs left this roost on September 2nd with arrival of cold front. Click face for larger image.
miles of corn and soybean fields, these 40 acres of flowers seemed to be a magnet for hungry butterflies. ?." (More)
Elizabeth Donnelly & Jim Hillegass, Minneapolis, Minnesota

August 28 Ontario
"On 28 August I witnessed perhaps the largest flight of Monarchs I've ever seen. Approximately 1000/minute were coming ashore?.in 2 hours about 120 000 passed??"(More)
Bob Curry, Ancaster, Ontario. Credit: Leps-l (Lepidopterists' listserv)

August 31 Ontario
"Thousands of monarchs are gathering in the area and have been observed along the north shore of Lake Ontario?." (More)
Sam Conroy, Trenton, Ontario

September 2 Minnesota
The first strong cold front of the fall hit Northern regions, and some interesting observations were made: "There were between 500 and 800 butterflies here on September 1st. Temperatures dropped late afternoon and the next day the butterflies were gone?." (More)
Pari Ditmar, Glencoe, Minnesota

September 3 Iowa
Two days later, and 250 miles down the trail, Kathy Reed reported from Malvern, Iowa: "Sept 3 was the first night we noticed monarchs roosting in our trees?? (More)
Kathy Reed, Malvern, Iowa

September 3 Ontario
The same cold front affected the migration sightings along Lake Ontario:
"The cold has greatly reduced numbers here since Wednesday (9/3/97). Last Thursday (8/28/97) there were many migrants here. I found a roost of 300 or so?.and again on Tuesday (9/2/97) there were another 300, most on exactly the same tree, exactly the same branch?.." (More)
Rod Murray, Streetsville, Ontario

September 3 Ontario
"I have seen very few butterflies now. The odd one will fly by, as if in no hurry. Our weather has changed quite a bit in the last couple of days. Tuesday Sept. 2/97 the temperature was approx. 26c (79F). Today it is around 19c (66F)."
Jacqueline Rimmer Burlington, Ontario, Canada (rimmer@worldchat.com)

As a cold front pushes into Nebraska on September 8th, monarch sightings suddenly increase. Click weather map for a larger image.
September 8 Nebraska
"What a difference a day makes! Yesterday, here and there a lonely Monarch was making the way south. Today as we left school there were nearly 200 monarch butterflies resting in the shade. We are having a cold front approach and some nasty looking storm clouds coming from the north ,so our butterflies should get a strong push south??" (More)
Gayle Kloewer, York, Nebraska

Generation Xtraordinaire
The monarchs you see today are the same butterflies we will track carefully next spring, as they return from Mexico. The vivid colors of their fresh wings will be faded after the long migration and winter months.

This monarch generation is very long-lived compared to the monarch generations of summer. During the summer, monarchs live for only a few weeks. They quickly produce the next generation and die. In contrast, monarchs of late summer do not enter the breeding condition. The shorter days and cooler temperatures trigger a hormonal change, and the monarchs go into a state known as "sexual diapause". Monarchs of this generation will live some 8-9 months--and undertake a spectacular migration to Mexico in between.

In the spring, today's butterflies will become sexually mature. They will mate and return to the southern part of their breeding range. It is their children who will repopulate the north--and begin the cycle of summer generations again.

Coming Next Week
Location of Cape May, New Jersey
Why do you think Cape May is such a good place to watch for migrating monarchs? (See Challenge Question # 1 below.) Click map for a larger image.
We'll visit Cape May, New Jersey where the Monarch Migration Project is now underway. For the 6th year in a row, people there are monitoring the migration by systematically counting monarchs 3 times a day. Each year, the migration has reached a peak in the middle of September at Cape May. In fact, September 19th has been the record day for several years in a row. According to Dick Walton, Program Director, the monarchs tend to move when cold fronts arrive.

Try This!
Watch the weather in New Jersey closely this week! Check out the links below to some of the best spots for weather-watching. Also, see if you can answer our first Challenge Question of the season.

Challenge Question #1
"Why do you think Cape May is such a good place to watch for migrating monarchs?"

How to Respond to Journey North Monarch Challenge Question # 1

  1. Address an e-mail message to: jn-challenge-monarch@learner.org
  2. In the Subject Line of your message write: Challenge Question # 1
  3. In the body of the message, answer today's question:

Don't Forget!
Please include the name of your school and your location so we can credit you properly for your answers.

The Next Monarch Migration Update Will be Posted on September 15, 1997