Sites in the central and northern zone were encompassed by the creation of the Monarch butterfly Biosphere Reserve (56,259 ha) in the year 2000, on the limits of Estado de México and Michoacán. The core zones (13,551 ha) of the Reserve are found above 3,000 masl in fir forests and are known as Cerro Altamirano (588 ha in the north), Sierra Chincua-Campanario-Chivatí-Huacal (9,671 ha in the center) and Cerro Pelón (3,339 ha in the south).
The hibernation sites are found in temperate forests above 3000 masl. The vegetation of these mountains is dominated by oak (Quercus laurina, Q. acutifolia, Q. rugosa, Q. castanea, Q. obtusata, Q. salicifolia, Q. crassifolia) and pine/oak forests on the lower slopes, and pine (Pinus pseudostrobus, P. oocarpa, P. michoacana, P. rudis, P. teocote, P. ayacahuite, P. hartwegii) and fir (Abies religiosa) forests in higher areas. There are also white cedar (Cupressus lindleyi) and mountain juniper (Juniperus deppeana, J. monticola) and prairies of Potentilla candicans (SEMARNAT 2001) and agricultural fields can be found up to elevations of 3000 masl.
There are four regions in which hibernation sites have been recorded. These regions form a line of approximately 120 kilometers from northeast to southeast along the length of the Balsas basin continental divide. The four regions are all included within the area delimited by 18°59'25" to 19°58'21" N and 98°41'37" to 100°49' W.
Northeast: Sierra de San Andres and Sierra de Mil Cumbres in Michoacán
North: Cerro Altamirano in Michoacán
Center: Sierra Chincua and Sierra del Campanario, in Michoacán and Estado de México. All of these Sierras delimit the states of Michoacán and Estado de México.
Southeast: Western slope of the Nevado de Toluca in Estado de México
A fifth region, on the western slope of the volcano Popocatépetl, 10 kilometers to the southeast of Atlauta in Estado de México, is more than 100 kilometers away from the other sites and, due to its small size, has never been included in the monitoring program.
Within the four regions, around 22 hibernation sites have been identified (Table 1).
Table 1. Regions, mountain chains, sites of the colonies and states in which groups of the Monarch butterfly have historically been found.
- Sierra de San Andrés (Los Azufres)
- Colonia de Pízcuaro
- Colonia de Los Azufres
- Sierra de Mil Cumbres
- San Andrés
- Río de Parras
- Puerto Morillo
- Cerro Altamirano
- Colonia Contepec
Central Northern region
- Sierra de Chincua
- Colonia Llano del Koala
- Colonia Llano del Toro
- Colonia Mojonera Alta
- Colonia El Zacatonal
- Colonia Puerto Bermeo
- Sierra de San Andrés (Los Azufres)
- Michoacán and Estado de México
- Sierra del Campanario
- Colonia El Rosario
- Colonia Cerro Blanco
- Colonia Piedra Boluda
- Colonia El Picacho
- Colonia Lomas de Aparicio
- Colonia Los Trozos
Central Southern region
- Cerro Pelón
- Colonia El Cedral
- Colonia Carditos
- Colonia Santa Teresa
- Colonia Las Lagunitas
- Sierra del Campanario
- Estado de México
- Nevado de Toluca
- Colonia Piedra Herrada
- Colonia San Francisco
- Colonia Palomas
- Nevado de Toluca
Prior to this declaration, there was an evolution in terms of declaring protected areas in the zone. First, the Fauna Reserve and Refuge Zones in 1980 protected hibernation zones without specifying locations and restricting extractive activities only during the season of hibernation (November to March). The Special Biosphere Reserve of the Monarch butterfly (16,110 ha) defined the location of five areas in 1986 and the name was later changed to Monarch Butterfly Protected Natural Area in 1996.
The Reserve extends along the frontier of the states of Michoacán and Estado de México, including the municipalities of Temascalcingo, San José del Rincón, Donato Guerra and Villa de Allende (in Estado de México) and Contepec, Senguio, Angangueo, Ocampo, Zitácuaro and Áporo (in Michoacán).
The area of the reserve includes 93 different owners: 59 ejidos, 13 indigenous Mazahua and Otomí communities and 21 small property owners, in addition to featuring state and federal properties.
What is a sanctuary?
A sanctuary is a place that hosts flora, fauna, exceptional landscapes or natural events that make it UNIQUE, and must be protected and respected for its fragility and importance to nature and society. In the case of the Monarch butterfly, the forest areas in which they hibernate are considered sanctuaries. These sites provide them with protection from extreme climatic events and the peace they require in order to save the fats that they use as a fuel for their return journey. Every time the butterflies are disturbed and fly, they use energy they need in order to be able to make the return journey.
In order to visit the Monarch butterflies you can:
In Michoacán, visit the sanctuaries of Ejido El Rosario in the Sierra Campanario, Ejido Cerro Prieto and Ejido Senguio in the Sierra Chincua.
In Estado de México, visit Ejido La Mesa in Sierra Campanario, Ejido El Capulín in Cerro Pelón and Ejido San Mateo Almomoloa in Piedra Herrada.
Responsible tourism is defined as the attitude of respect in relation to the places and people with which a tourist comes in contact throughout their visit, and is characterized by:
Respect for the environment.
Minimizing negative economic, environmental and social impacts.
Creating benefits for local people and improving the wellbeing of local communities. Involving local people in decisions that affect their lives and life opportunities.
Making positive contributions to the conservation of natural and cultural heritage, aiding conservation of the cultural diversity of the world.
Providing more agreeable experiences for the tourists through contact with the local population and a greater understanding of the social and environmental aspects of the local culture.
Being culturally sensitive, promoting respect and understanding among tourists and hosts and contributing to the development of trust and local pride.
There are a series of recommendations for visitors to the sanctuaries:
"Code of conduct for the responsible tourist"
- I follow the indications and instructions of local guides.
- During my trip, I follow the established pathways.
- I do not introduce foods, alcoholic beverages, sharp objects, firearms or pets to the sanctuaries.
- I do not take plants, animals, fungi or any other element that forms part of the forest.
- I do not smoke or start fires.
- I respect the limits of access for observing the Monarch butterfly colonies.
- I remain silent during my time in the sanctuary.
- I do not use a flash to take photographs.
- I do not disturb, touch or take Monarch butterflies.
- I do not stay more than 18 minutes within the sanctuary, in order to give the chance to other people to live this experience without changing the hibernation status of the butterflies.
Arrival of the Monarch butterflies to the hibernation sites.
- On arrival, they spend several days flying around before locating the best place for their hibernation. During this month, it is best not to visit them in order not to interfere with their selection.
- December to January
Establishment of colonies for hibernation.
- They group, forming clusters on the branches of the trees to protect themselves from the cold during the winter.
- February to March
Reproductive activity begins (nuptial flight).
- There is more activity as the days get warmer; they are observed in flight, mating, taking water and nectar in preparation for their return to the north of Mexico and south of the United States in order to produce the following generation.
|In nature, everything has a reason to be: the Monarch butterflies are living beings that form part of the food web in the forests of the sanctuaries. Some die as part of their natural process and become food for mice and birds that eat their abdomen for the fats it contains. The large quantity of dead Monarch butterflies in the sanctuaries generates a large concentration of chemical substances. Currently, researchers are studying the possibility that this high concentration helps the Monarch locate the hibernation sites.|
|Monarch butterfly wings are formed by thousands of scales that are very sensitive to touch and easily broken. When we touch them they lose some scales that protect them and, as a consequence, they are more exposed to all of the environmental factors (cold, light and wind) that put their lives at risk. It is like if we had a third degree burn.|
|Repeated exposure to camera flashes changes the state of hibernation of the Monarch butterflies. They perceive this light and move; they may detach from the trees and become separated from their colonies. Once separated, they are more exposed to the cold and to their natural predators.|
|Monarch butterflies travel up to 4000 km to escape the winter cold of the north of the continent. During their journey of up to two months, they avoid a series of situations that put them at risk and when they arrive to Mexico they need to rest in the sites that they themselves choose in order to group and form colonies that protect them and keep them alive over the winter. Monarch butterflies developed the capacity to hibernate; this means that they are adapted to lower their metabolism and temperature, put their reproductive status on pause, rest and live from the fats stored within their bodies during the journey until arriving at the sanctuaries. We must not forget that they are very sensitive to our presence and that each time they move in the state of hibernation we weaken them since they expend energy (fat) with these movements. They need this energy to protect them against the inclemency of the environment (cold, rain, hail, wind and frost) and to return to the north of Mexico and south of the United States. It is like being exposed to the cold with a degree of anemia.|
|Monarch butterflies remain in a state of hibernation during the months of December, January and part of February. Excess noise stresses them and interrupts their rest, making them expend energy and reducing the possibility that they survive the return flight.|
|With their antennae, the Monarch butterflies detect the carbon dioxide (CO2) that we expel during respiration. A high concentration of CO2 disturbs them, causing them to fly and detach from their colonies. This leads them to expend energy, leaving them vulnerable to the climate and to their natural predators.|
|Solid organic (food wastes) and inorganic (wrappers and plastic bags, among others) residues contaminate the hibernation areas of the Monarch butterfly.|
|It is a place that hosts flora, fauna, exceptional landscapes or natural events that make it UNIQUE and must be protected and respected for its fragility and importance to nature and society.|
|This is the seasonal displacement carried out by some species of animals from one place to another, with the aim of finding the best place to reproduce, avoiding extreme climates or searching for food.|
|This is the capacity of some organisms to lower their metabolism and temperature, pause their reproductive status, rest and feed from stored reserves until the external environmental conditions are more favorable.|
|It is a plant, commonly known as "milkweed", on which the caterpillars of the Monarch butterfly depend for food during the first stage of their biological cycle. The genus Asclepias has approximately 140 different species; the best known of these is Asclepias curassavica with orange and yellow flowers and white sap. These are toxic plants, but the caterpillars store the toxin and use it as a mechanism of protection against their natural predators.|
|This is the interruption of the reproductive cycle of certain organisms, such as insects, for a defined period of time and is generally associated with climate and restarts when environmental conditions more suitable for reproduction are presented.|
Monitoring of populations in the hibernation sites began regularly in 1993. Despite congregating in relatively small areas (between 0.5 and 20 hectares), there are great difficulties in estimating Monarch populations. To date, the area (hectares) occupied by the butterflies in the month of December has been used for populational estimation. The information presented in the monitoring reports is the accumulated surface of the aggregations of butterflies.
During the past 20 years (1993 to 2013), the area occupied by the Monarch butterflies in Mexico has varied from 0.67 to 21 hectares. Thus, millions of butterflies that occupy more than 3 million square kilometers of the United States and Canada during the reproductive period congregate in less than 20 hectares in Mexico.