Here is a detailed article on one of most impressive natural journeys that is also part of Mexico's Traditions, the voyage of the Monarch Butterfly from North America to Mexico.
Year after year when autumn comes, following a millennial call whose origin remains a puzzle to Man, the monarch butterfly of North America undertakes the longest known voyage in the insect world.
After spending the summer months in the native fields and forests of central and northeastern United States and southeastern Canada, millions of these fragile insects start a 3,000 mile migration south so that they can enjoy the winter in central Mexico's splendid Sierra Madre Oriental mountain range.
The destination during the voyage of the monarch butterfly (Danaus plexippus) was for a long while a unsolvable puzzle for researchers. But in 1975 the Canadian zoologist Dr.. Fred A. Urquhart, in partnership with Kenneth Brugger and Rafael Sanchez Castaneda, discovered their secret. The butterflies were enjoying the glacial period of winter in the dry brook beds and valleys of the high Sierra Madre mountains, at an altitude of 9 to ten thousand feet in an area that is in between the states of Michoacan & Mexico State, in the central area of Mexico.
Urquhart wrote about their discovery: "I watched in surprise at the view. Butterflies, millions and millions of monarch butterflies! They stuck in thickly packed masses to each and every branch and tree trunks of the tall, gray-green oyamel trees. They swirled thru the drafts like autumn leaves and covered the ground in their flaming colored myriads on this Mexican hillside."
This discovery provided one of the most superb revelations about the natural world. Suddenly, as if drawn by a forceful magnet, these frail summer residents of a massive territory that covers over half of the United States, migrate south in hurried hordes in an excursion that takes them south over prairies, valleys, mountains, deserts and cities, crossing the Mexican border thru Texas, to converge by the millions, like orange-colored tributaries of some great stream, into a region in central Mexico where the Sierra Madre and the Volcanic Belt mountains meet.
A relatively modest sized forest of only 12,500 acres is the sanctuary where the monarch butterflies pass the winter and copulate before returning up north again in the spring months.
Even though this seemed to be a fantastic discovery for the scientific community, it was considered general knowledge to the area's inhabitants. These creatures had been part of their daily lives since time immemorial. Pre-Hispanic inhabitants attached great importance to the monarch butterfly, which played a major role in their local religion, myths, and were regularly pictured in their art.
Associated with fire and the movement of the sun, butterflies or papalotl represented the souls of warriors who had died in battle or on the sacrificial altar. It was believed that after traveling with the Sun for 4 years, they would return to earth as butterflies, to feed on the sweet nectar of flowers. This belief, most likely, also applied to monarch butterflies, "daughters of the Sun" whose annual migration represented the renewing cycle of Nature.
In 1986, eleven years after Urquhart's discovery, the Mexican Govt protected this ecologically important mountain area by establishing the Monarch Butterfly Special Ecosphere Reserve. A total of around forty thousand acres of forest were declared protected areas for the migration, wintering and reproduction of the monarch butterfly, as well as for the conservation of its vital environment.
Summer residence of the Monarch Butterfy
In the summer, monarch butterflies live in an area that covers 1.5 million square miles and that extends from southern Canada to the southern tips of the Sierra Nevada, the Rocky Mountains to the West and the Appalachians to the East inside the US of America. This area abounds with milkweed (Asclepias), the only plant on whose leaves the larvae of this species can feed. This plant also contains a poisonous alkaloid that makes the larvae impervious to many natural predators, and supplies the pigment which gives these butterflies their particular coloration.
The longer days and high summer temperatures of this region allow the monarch butterfly to grow and reproduce. During those months, its life cycle is like that of any other butterfly. They live from 2 to six weeks, in which they reproduce, lay their eggs and, shortly thereafter, die.
Nevertheless the generation that stems from the cocoons under the September sun has a totally different destiny than that of its elders and grandparents. After the fall equinox, as the days grow shorter and temperatures drop, the autumn butterflies suffer a series of hormonally-based changes which repress their reproductive system, stopping sexual maturity, and allowing them to save energy and live much longer than their parents.
Instead of generating the urge to pair, the shortening days create in these creatures another insistent need, of similar importance for their survival as reproduction... An urge to journey south, towards warmer areas where they can live through the winter chills, postponing their reproduction cycle until the following season.
Hence they must travel so as to preserve the species. If they survive the life-threatening journey, they can live up to 9 months, more than ten times longer than any other butterfly.
Monarch Butterflies and their amazing migration
After storing enough energy and fat in the summer months, these indefatigable travelers will fly as much as 3,000 miles to reach their Mexican wintering grounds. They fly twenty four seven, and rest in the night, sleeping on tree branches in groups of nearly 600 butterflies.
Dependent on the winds, they can travel at a velocity from nine to twenty-seven miles an hour, covering as much as 80 miles in daily eight-hour shifts. Their favourite routes lie along low open valleys, where they can best take advantage of the north winds to push them along in open-winged glides, which enables them to fly long distances easily. This is the way the monarch butterflies can make their 3,000 mile journey in only one month.
By mid-November, the green crevasses of the Mexican butterfly sanctuaries, inhabited by oyameles or firs, oaks and spruces, change to shades of ochre, brown and orange. Leaves and pine needles become frosted with a strange texture created by the wings of the millions of butterflies that hang in thick clusters, from the tree branches. Here they survive the winter cold, in a state of semi-hibernation that allows them to save their energy and fat till spring arrives.
The monarchs return
Warmer days and longer daylight hours send their age-old signals to the sleeping monarchs telling them that spring has returned. They start to stir and flap off the sleepiness of their long sleep. They slowly open their wings to let the sun heat in and to warm their bodies.
Bit by bit the air comes alive and orange tinted, with hundreds and hundreds of butterflies that fly around from flower to flower ingesting the sweet nectar that will nourish and give them strength and energy for their homeward trip.
Light, heat, and their new-found liberty excite their sexual maturity once again. Their buried instincts take over, giving way to courting rituals and intercourse. And then, without further circling, just as when they suddenly started their trip south five months before, as if moved by an internal clock that urges them to go back home, they begin their return journey. Swarms of butterflies rise up into the air, their thrashing wings creating a muted throb in search of air currents which will carry them away.
Their numbers have recently been diminished. Many have died from the rain or from the winter cold. Mating has additionally taken a heavy toll on most of the males, who invested their last energies in the reproductive act, and then died.
But among the survivors are a large number of fertilized females who, during their way back home, will deposit their eggs on their nightly stops to rest. Two weeks later these eggs will hatch into caterpillars, which will soon become chrysalis that, in the late spring, will metamorphose into butterflies.
Of these, only a few will remain to copy the cycle there, where they were born. The rest will continue northward to a home they don't yet know, where, like countless generations before them, they are going to live, friend and die. And it will not be their young, or their offspring's young, but the next generation of butterflies, those born at the end of summer that may again respond to the call to migrate south, as their ancestors did the year before, beginning another cycle.
The Conundrums of the Monarch Butterfly
It is still a mystery how these tiny, fragile insects know which road to follow, since the winter visitors were born in the far-off forests of the U. S. and Canada, and the sovereigns reproduced in Mexico will never return there.
How does a whole generation of monarchs travel an one or two thousand mile route that neither they, nor their mother and father, have ever flown before? How do their descendants, born after the winter season along the migration back north, manage to find a way to go back to their parents' place of origin?
Again, how does such a tiny, frail and exposed creature come up with a way to survive the rigors of traveling such long distances exposed to the sun, the rain, the cold and the depredation of man? Where does such a tiny body accumulate so much energy? What makes it so tireless? How can an insect be so magnificent?
Many answers have been proposed for these enigmas, but still none is definite. But one thing is clear. The monarch butterfly is one of the most astonishing creatures on this planet. And, the more we're are able to know about it, the more amazing it becomes.
This long distance traveler, citizen of the planet, is the most fragile and gorgeous symbol of the transformation and renewal of Nature. Above all else , it's a prime example of a species' instinct to survive.
Little wonder our ancestors venerated the Monarch Butterfly and this is why it's so important that we protect them.
Year after year when autumn comes, following a millennial call whose origin remains a puzzle to Man, the monarch butterfly of North America undertakes the longest known voyage in the insect world.
After spending the summer months in the native fields and forests of central and northeastern United States and southeastern Canada, millions of these fragile insects start a 3,000 mile migration south so that they can enjoy the winter in central Mexico's splendid Sierra Madre Oriental mountain range.
The destination during the voyage of the monarch butterfly (Danaus plexippus) was for a long while a unsolvable puzzle for researchers. But in 1975 the Canadian zoologist Dr.. Fred A. Urquhart, in partnership with Kenneth Brugger and Rafael Sanchez Castaneda, discovered their secret. The butterflies were enjoying the glacial period of winter in the dry brook beds and valleys of the high Sierra Madre mountains, at an altitude of 9 to ten thousand feet in an area that is in between the states of Michoacan & Mexico State, in the central area of Mexico.
Urquhart wrote about their discovery: "I watched in surprise at the view. Butterflies, millions and millions of monarch butterflies! They stuck in thickly packed masses to each and every branch and tree trunks of the tall, gray-green oyamel trees. They swirled thru the drafts like autumn leaves and covered the ground in their flaming colored myriads on this Mexican hillside."
This discovery provided one of the most superb revelations about the natural world. Suddenly, as if drawn by a forceful magnet, these frail summer residents of a massive territory that covers over half of the United States, migrate south in hurried hordes in an excursion that takes them south over prairies, valleys, mountains, deserts and cities, crossing the Mexican border thru Texas, to converge by the millions, like orange-colored tributaries of some great stream, into a region in central Mexico where the Sierra Madre and the Volcanic Belt mountains meet.
A relatively modest sized forest of only 12,500 acres is the sanctuary where the monarch butterflies pass the winter and copulate before returning up north again in the spring months.
Even though this seemed to be a fantastic discovery for the scientific community, it was considered general knowledge to the area's inhabitants. These creatures had been part of their daily lives since time immemorial. Pre-Hispanic inhabitants attached great importance to the monarch butterfly, which played a major role in their local religion, myths, and were regularly pictured in their art.
Associated with fire and the movement of the sun, butterflies or papalotl represented the souls of warriors who had died in battle or on the sacrificial altar. It was believed that after traveling with the Sun for 4 years, they would return to earth as butterflies, to feed on the sweet nectar of flowers. This belief, most likely, also applied to monarch butterflies, "daughters of the Sun" whose annual migration represented the renewing cycle of Nature.
In 1986, eleven years after Urquhart's discovery, the Mexican Govt protected this ecologically important mountain area by establishing the Monarch Butterfly Special Ecosphere Reserve. A total of around forty thousand acres of forest were declared protected areas for the migration, wintering and reproduction of the monarch butterfly, as well as for the conservation of its vital environment.
Summer residence of the Monarch Butterfy
In the summer, monarch butterflies live in an area that covers 1.5 million square miles and that extends from southern Canada to the southern tips of the Sierra Nevada, the Rocky Mountains to the West and the Appalachians to the East inside the US of America. This area abounds with milkweed (Asclepias), the only plant on whose leaves the larvae of this species can feed. This plant also contains a poisonous alkaloid that makes the larvae impervious to many natural predators, and supplies the pigment which gives these butterflies their particular coloration.
The longer days and high summer temperatures of this region allow the monarch butterfly to grow and reproduce. During those months, its life cycle is like that of any other butterfly. They live from 2 to six weeks, in which they reproduce, lay their eggs and, shortly thereafter, die.
Nevertheless the generation that stems from the cocoons under the September sun has a totally different destiny than that of its elders and grandparents. After the fall equinox, as the days grow shorter and temperatures drop, the autumn butterflies suffer a series of hormonally-based changes which repress their reproductive system, stopping sexual maturity, and allowing them to save energy and live much longer than their parents.
Instead of generating the urge to pair, the shortening days create in these creatures another insistent need, of similar importance for their survival as reproduction... An urge to journey south, towards warmer areas where they can live through the winter chills, postponing their reproduction cycle until the following season.
Hence they must travel so as to preserve the species. If they survive the life-threatening journey, they can live up to 9 months, more than ten times longer than any other butterfly.
Monarch Butterflies and their amazing migration
After storing enough energy and fat in the summer months, these indefatigable travelers will fly as much as 3,000 miles to reach their Mexican wintering grounds. They fly twenty four seven, and rest in the night, sleeping on tree branches in groups of nearly 600 butterflies.
Dependent on the winds, they can travel at a velocity from nine to twenty-seven miles an hour, covering as much as 80 miles in daily eight-hour shifts. Their favourite routes lie along low open valleys, where they can best take advantage of the north winds to push them along in open-winged glides, which enables them to fly long distances easily. This is the way the monarch butterflies can make their 3,000 mile journey in only one month.
By mid-November, the green crevasses of the Mexican butterfly sanctuaries, inhabited by oyameles or firs, oaks and spruces, change to shades of ochre, brown and orange. Leaves and pine needles become frosted with a strange texture created by the wings of the millions of butterflies that hang in thick clusters, from the tree branches. Here they survive the winter cold, in a state of semi-hibernation that allows them to save their energy and fat till spring arrives.
The monarchs return
Warmer days and longer daylight hours send their age-old signals to the sleeping monarchs telling them that spring has returned. They start to stir and flap off the sleepiness of their long sleep. They slowly open their wings to let the sun heat in and to warm their bodies.
Bit by bit the air comes alive and orange tinted, with hundreds and hundreds of butterflies that fly around from flower to flower ingesting the sweet nectar that will nourish and give them strength and energy for their homeward trip.
Light, heat, and their new-found liberty excite their sexual maturity once again. Their buried instincts take over, giving way to courting rituals and intercourse. And then, without further circling, just as when they suddenly started their trip south five months before, as if moved by an internal clock that urges them to go back home, they begin their return journey. Swarms of butterflies rise up into the air, their thrashing wings creating a muted throb in search of air currents which will carry them away.
Their numbers have recently been diminished. Many have died from the rain or from the winter cold. Mating has additionally taken a heavy toll on most of the males, who invested their last energies in the reproductive act, and then died.
But among the survivors are a large number of fertilized females who, during their way back home, will deposit their eggs on their nightly stops to rest. Two weeks later these eggs will hatch into caterpillars, which will soon become chrysalis that, in the late spring, will metamorphose into butterflies.
Of these, only a few will remain to copy the cycle there, where they were born. The rest will continue northward to a home they don't yet know, where, like countless generations before them, they are going to live, friend and die. And it will not be their young, or their offspring's young, but the next generation of butterflies, those born at the end of summer that may again respond to the call to migrate south, as their ancestors did the year before, beginning another cycle.
The Conundrums of the Monarch Butterfly
It is still a mystery how these tiny, fragile insects know which road to follow, since the winter visitors were born in the far-off forests of the U. S. and Canada, and the sovereigns reproduced in Mexico will never return there.
How does a whole generation of monarchs travel an one or two thousand mile route that neither they, nor their mother and father, have ever flown before? How do their descendants, born after the winter season along the migration back north, manage to find a way to go back to their parents' place of origin?
Again, how does such a tiny, frail and exposed creature come up with a way to survive the rigors of traveling such long distances exposed to the sun, the rain, the cold and the depredation of man? Where does such a tiny body accumulate so much energy? What makes it so tireless? How can an insect be so magnificent?
Many answers have been proposed for these enigmas, but still none is definite. But one thing is clear. The monarch butterfly is one of the most astonishing creatures on this planet. And, the more we're are able to know about it, the more amazing it becomes.
This long distance traveler, citizen of the planet, is the most fragile and gorgeous symbol of the transformation and renewal of Nature. Above all else , it's a prime example of a species' instinct to survive.
Little wonder our ancestors venerated the Monarch Butterfly and this is why it's so important that we protect them.
About the Author:
Guadalupe Q. Pali is a mag editor in Mexico, writes many articles on traveling in Mexico and its natural marvels, including some like What to do in Puerto Vallarta, that is part of the Puerto Vallarta's Travel Guide
web site.
web site.
No comments:
Post a Comment