FINAL Monarch Migration Update: November 15, 1998 Today's Report Includes: Millions of Monarchs Arrived Last Week at Mexico's Sanctuaries Plans for Journey North 1999 Knowing When to Stop Challenge Question #14 Please Report the LAST Monarch You See This Season 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: Date # Trees Filled With Monarchs 10/28/98 6 trees 11/06/98 12 trees 11/15/98 467 trees 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. Today was the official opening of the sanctuaries. The Mexican government announced the opening of a 3rd sanctuary for tourism this year, as part of the effort to bring income to the people who live here. (The 3rd site is called "La Mesa". It is actually part of the Campanario sanctuary, but tourists will enter from the northeast side, in the state of Mexico.) Back at the entrance of Sierra Chincua, the families of the Los Remedios "ejido" community were gathering for a mass to celebrate the arrival of the monarchs. "El Padre viene ahora," said the people as the priest arrived. 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: Eighteen year old Diego Gonzalez Martinez, a guide at the Sierra Chincua Sanctuary, will report to us weekly on the behavior of monarchs wintering at Sierra Chincua. 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. Beginning on February 9th, watch for weekly reports from the overwintering sites until the migration begins in March. 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 last sanctuary!" Try This! The 10 readings below were collected at a point directly south of El Pelon. Draw a compass. Then make an arrow to show the direction each monarch was traveling. How would you answer this question? Challenge Question # 14 "In which directions were the monarchs south of El Pelon going on November 5th? Do the data collected that day reveal a pattern?" Vanishing Azimuth of 10 Butterflies Direction Monarchs Were Traveling (in degrees) Wind Direction = 210 degrees 285 358 258 249 181 161 167 220 249 268 How to Respond to Today's Challenge Question: Address an e-mail message to: jn-challenge-monarch@learner.org In the Subject Line of your message write: Challenge Question # 14 In the body of each message, answer the question in today's report. 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! Elizabeth Donnelly Journey North This is the FINAL Monarch Migration Update Until February, 1999. Copyright 1998 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form