FINAL Monarch Migration Update: November 15, 1998
Today's Report Includes:
Millions of Monarchs Arrived Last Week at Mexico's Sanctuaries
I'm writing this final update from the Sierra Chincua monarch sanctuary near Angangueo, Mexico. Without question, the monarchs arrived here during the past 8 days by the millions. Our guide, 18 year old Diego Gonzalez Martinez, observed their arrival as follows:
I was astonished to find the forest filled with monarchs where I had not seen a single one 14 days earlier--and only a handful 10 days ago. After the 1-hour walk to the site, we sat in silence and simply stared. There were the monarchs, finally at rest. They were clinging tightly to the branches of the oyamel fir trees, and I could actually see the branches bending under the weight of so many butterflies. As the sun came out from behind a cloud, the silence of the forest was broken. In response to the warmth, millions of butterflies opened their wings until gradually it sounded like a soft rain. Having just seen symbolic monarchs arrive from far and wide, I wondered where each single butterfly had come from. This place is a sanctuary in the truest sense, I thought.
Plans for Journey North 1999
Now that the monarchs have reached their winter home, this is the final migration update. While here in Mexico, we arranged the following so that you'll receive news from the wintering grounds when Journey North begins next February:
A weather station will be delivered to the nearby mountain school, "Pedro Ascencio". The students there will monitor the local climate, keeping records of those factors that affect the monarchs during the winter, such as temperature, precipitation and cloud cover. You may be surprised to see how cold it gets in the monarch's mountains during the winter!
Your symbolic monarchs are now being
delivered to students who live beside the monarch sanctuaries. We've arranged "home visits" with 2 students
who are caring for butterflies, so you'll have a glimpse of life in this region. We'll also introduce you to over
100 students whose families own the land inside the sanctuaries. You may see a picture of YOUR symbolic butterfly
with one of them.
Knowing When to Stop
Monarch biologist Dr. Bill Calvert wonders: After flying southward toward this small region of Mexico for as many as 2 months, aiming at a target only 70 miles wide, how do monarchs know when to stop? Monarchs clearly have an internal compass which guides them in the right direction. But do they also have an internal map that tells them when they've arrived? That is, do they have a "homing instinct"?
I joined Dr. Calvert on November 5 to see what we would find SOUTH of the sanctuary region. We traveled entirely around the El Pelon site that day. El Pelon is located on the south face of the Transvolcanic range. (See map.) Because there are no mountains south of El Pelon with suitable habitat for monarchs, any butterflies still heading south are presumably "overshoting" their target.
With a compass, we stood directly beneath the butterflies as they flew overhead. We watched individual butterflies
carefully until they vanished, then recorded the direction in which each was traveling. (This is called the "vanishing
azimuth".) Sure enough, we did find monarchs heading southward. Some were flying their little hearts out,
straight into the south wind. "Turn around, " I wished I could tell them, "You've just passed the
How to Respond to Today's Challenge Question:
Please Report Your LAST Monarch Sighted This Season
Not all monarchs make it to Mexico. In fact, in most years they can be found in the Gulf States during the winter. Please help document their locations this winter. Wherever you live, report the date of the LAST monarch you see this season.
See You in February!
This is the FINAL Monarch Migration Update Until February, 1999.
Copyright 1998 Journey North. All Rights Reserved.