What is the Mountain of Butterflies? Important Things You Should Know

What is the mountain of butterflies? It is a phenomenon that happens every year. Most aviation animals usually fly south for the winter. Same goes for the Monarch Butterfly. In the month of January, millions of butterflies who fly south, congregate in what is known as the Mountain of Butterflies. Now a nature reserve, this site is home to an entire species for the span of a few months, while they wait out the harsh winters of the north.

[amazon_link asins=’B01220GQ4O,B00CLESJKG,B0723BJZFM,B071XCX2L2,B01ETP8Q3O’ template=’ProductCarousel’ store=’gree0ab-20′ marketplace=’US’ link_id=’07f4f554-8347-11e7-9067-236de13ad09a’]


What is The Mountain of Butterflies

In January, 42 years ago, scientists made an amazing discovery. Nearly 10,000 feet above sea level, and about 60 miles northeast of Mexico City, is home to the Mountain of Butterflies. This is the wintering destination for millions of migrating Monarch butterflies. This area is under protection as the Monarch Butterfly Biosphere Reserve.


The breakthrough of this phenomenon was made by citizen scientists Ken Brugger and his Mexican native wife, Catalina. They had spent two years in the mountains searching for the migration destination. They are part of a larger group. A volunteer effort led by Dr. Fred Urquhart, a Canadian zoologist. Urquhart wrote when announcing the discovery with National Geographic, “I gazed in amazement at the sight. Butterflies, millions upon millions of Monarch butterflies! They clung in tightly packed masses to every branch and trunk of the tall, gray/green oyamel trees. They swirled through the air like autumn leaves and carpeted the ground in their flaming myriads on this Mexican mountainside. Breathless from the altitude, my legs trembling from the climb, I muttered aloud, ‘Unbelievable! What a glorious, incredible sight!’”

mountain of butterflies: cluster

The name Mountain of Butterflies comes from the sight of all of the butterflies clustered together on all of the trees on the mountain. It truly looks like a mountain of butterflies. That and the fact that their overwinter location is literally on a mountain. It’s popularity locally and around the globe has had people asking the question “what is the moutain of butterflies?”


These sites that Dr. Urquhart and his volunteer team found are in the states of Mexico and Michoacan. The mountain of butterflies appears during the months of October, when they first start arriving, and late March. The Monarch Butterfly Biosphere Reserve was created in 1986, nearly ten years after the Mountain of Butterflies was originally discovered.


Butterfly Migration – Where is the Mountain of Butterflies?

Every autumn, millions of the iconic orange and black critters fly about 3,000 miles south from Canada. They journey through the United States and land in the high altitude forests of Mexico’s Sierra Madre mountains. Here, they spend the winter months. Keeping warm and safe from the harsh cold on Canada. (Don’t you wish you could migrate to Mexico every winter.)


These butterflies migrate for two reasons. The first being they can not, of course, withstand the blistering cold temperatures in the northern and central continental climates during the winter (as many of us can not either.) The second reason is that the plants needed to feed their larvae do not grow in their winter hideouts. So, they must fly back north in the spring where the next generation can thrive.


These Monarchs can fly between 50 and 100 miles per day. They can only travel during the day because at night, they need to keep warm as the autumn night temperatures can get fairly cold. Congregation sites are very important to these butterflies. Often, the same sites are used year after year. The insects choose trees that have thick canopies that are able to moderate temperature and humidity. These trees include pine, fir, and cedars.


Why There?

The location of the Mountain of Butterflies is not chosen for a random reason. These butterflies recognize the usefulness of the forests in the mountains and found the climate and location to be perfect for overwintering. The mountain hillsides of the Oyamel forests provide the ideal microclimate for these butterflies. The temperature ranges from 0 to 15 degrees Celsius, which for Americans is 30 to roughly 60 degrees Fahrenheit. If the temperature was at all lower, the butterflies would have to use their fat reserves, which is like their last line of defense against the cold. However, the humidity of the Oyamel forests ensures that the butterflies will not dry out, which allows them to conserve more energy.


To stay warm, the Monarchs group together on the trees. Tens of thousands of butterflies can cluster on a single tree. Even though butterflies are obviously very small and weigh less than a gram each, when you get thousands of them in one place, they tend to weigh a lot. While the trees are usually capable of holding their combined weight, sometimes limbs break off.


Other Populations

The Sierra Madre mountains are not the only place that Monarchs migrate to during the winter. There is a decent population of butterflies that live west of the Rocky Mountains in North America. These select Monarchs migrate to southern California during the winter. The microclimates in areas like San Diego and Santa Cruz are very similar to that of Mexico. Also, instead of using Oyamel trees, this population choose to roost in Eucalyptus, Monterey Pines, and Monterey Cypress trees.


Prior Knowledge of the Mountain of Butterflies

Though the butterfly overwintering site was officially discovered and brought to public attention 42 years ago, the locals of the area had known about the Mountain of Butterflies for years. In the language of the native Purepecha people, who live in the region, their name for the Monarch Butterfly means “Harvest Butterfly”. This is because they find that they always arrive at the time of the corn harvest. “What is the mountain of butterflies” is a question largely asked by people outside that area. 


The butterfly is also associated with the Day of the Dead festival, which takes place at the end of October. This also, coincidently, is the same time that the butterflies begin their migration. According to traditional beliefs, the butterflies are the souls of the ancestors who are returning for their annual visit. There are many legends about the butterflies featuring in the area around Michoacan and the Mexico State borders. The Mexican President at the time, Jose Lopez Portillo, made the area a national park. It went through many changes in classification until it the UNESCO named it a World Heritage Site in 2008.


Threats to the Butterfly Habitat

As everything else, the butterfly habitats are also feeling the effects of types of pollution. Even though it was made as a wildlife reserve in 1980, the Mountain of Butterflies is still vulnerable to multiple threats. These include illegal logging, deforestation, and destruction caused by tourists.

Tourism Pollution

Tourism is a very large source of pollution of all kinds. One of the largest sources of tourism-based pollution, that should not be very surprising, is littering. In area with high traffic of tourists and interesting natural attractions, trash is a serious issue. This issue of improper waste disposal can be very damaging to the environment including rivers, beaches, scenic area, and roadsides. Using Caribbean cruise ships as an example, they produce more than 70,000 tons of waste every year. As a result, many cruise lines have begun to actively work against waste related impacts on the environment. The improper disposal of waste can affect the physical appearance of the water, shorelines and can even end up in the death of the wildlife.

Mountain of butterflies: trash


There are also many physical impacts from tourist activity as well. One of the most relevant to the Mountain of Butterflies is trampling. Trampling is when tourists while using the same trail multiple times, end up with the destruction of vegetation and soil degradation. This can lead to a loss of biodiversity. This even more dangerous when tourists decide to venture off the “beaten path”.

The trampling impacts on the natural vegetation include the breaking and bruising of stems, a reduction in the vigor of plants, reduction in the regeneration process, loss of ground covers like grass and moss, and a change in species composition. The effects of tourism on the soil can actually be more damaging. It should be known that the effects of vegetation and on the soil go hand in hand. These effects include the loss of organic matter, a reduction in soil macro porosity, which is the ability to allow water into the soil and drain quickly, a decrease in air and water permeability, increase in runoff, and an increase in erosion.


Tourist Effects on Monarch Butterfly Reserve

Tourism can be damaging to a lot of natural attractions and the Mountain of Butterflies, unfortunately, is no exception. Trash left by tourists is one of the nature reserve’s biggest threats. Despite Mexican and international efforts to maintain the site, littering still plagues the area. Trampling is another serious issue in the sanctuary as the butterflies rely on the vegetation to maintain themselves. The last issue is that when the temperature is warmer, the Monarchs like to fly close to the ground, often resting on the grassy bed. However, when tourists make their way through the reserve, some butterflies are often crushed. The reserve urges tourists to mind where they step and to try to be as gentle as possible. Making sure that your footprint is a small as possible should be a true goal for any tourist, no matter where you visit.


Loss in Population

Recently, there was a report that came out by the U.S. Fish and Wildlife Service saying that 970 million Monarchs had disappeared since 1990. That is a 90 percent population decline. The loss of population is the cause in part to herbicides that destroy milkweed. This is the plant that hosts the Monarchs eggs and provides food for the Monarch caterpillar. As a result, the Monarch is not able to reproduce properly The Fish and Wildlife Service announced an initiative to “Save the Monarch” and anyone can help with the efforts.


In addition, a study by the Natural History Museum of Los Angeles County said that the migration of butterflies to Mexico may be an endangered phenomenon. Lead conservation researcher Lincoln Brower made a statement in 2014 on a radio show, “The species will not go extinct. But if you think about this migration, it’s a unique biological phenomenon. And that phenomenon could go extinct.” A little reassurance in the fact that the Monarch will most likely stick around.

mountain of butterflies: caterpillar

Many organizations have been pushing for the United States and Canada, which is where the Butterflies go to reproduce, plant more milkweed. The Mexican government and many international conservation groups are hopeful for the population to grow 3-4 times the size it was back in 2014. Possibly able to cover 10 acres on the Mountain of Butterflies.


Visit The Mountain of Butterflies

It is very possible and encouraged for people to go visit the biosphere because it is truly a sight to behold and it raises awareness for the species. As long as tourists can maintain a low impact on the environment, the sites will remain open.

There are four sites that are open to the public. Two of them are in Michoacan, and the other two are in the state of Mexico. The original biosphere is on the eastern edge of Michoacan and crosses into Mexico. The two most popular sites are El Rosario and Sierra Chincua. El Rosario is near the town of Ocampo in Michoacan. Sierra Chincua is close to Angangueo, also in Michoacan.


Weekends, of course, are the busiest times, as that is when most people are free. The best times to visit and see the Monarchs at their most active is between January and March. This is when the population is the greatest and the air temperatures in the mountain are warmer. It is 10,000 feet above sea level so be prepared for thin air and high altitudes which can have an adverse affect on you.


Tips for Travel

Basic tips if you decide to visit the legendary Mountain of Butterflies. Bring water or buy bottled water there. Remember to recycle! Dress in layers. While climbing, it may be cold, especially as you reach the higher altitudes. When you reach the top, you will most likely become warm. Hence, layers. Also, bring a good pair of hiking shoes. Not sandals or flip flops. Keep to the trails. To maintain a low impact on the environment, do not stray from the trail. Doing so can and probably will damage the natural vegetation and any other animals living in the area. Sierra Chincua offers the opportunity to ride part of the trail on horseback. If you are either unable to hike the whole way on your own or just love horses, this is a cool choice.







Show Your Friends!
Patrick Sands

Hey, I'm Pat. I am a Millersville grad with a Bachelors of Arts in English. I love to write, play video games, watch movies and TV, basically be a total nerd whenever I can. Green and Growing is important to me because it allows me to help others be as green and eco-friendly as possible. With Climate Change being what it is, it is even more important for people to get educated about their environment. This website allows me to do my part in that. Also, I'm a huge goof who tries to add some humor into anything I write. Stay Excellent out there!

Click Here to Leave a Comment Below 0 comments