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by Monica Missrie, World Wildlife Fund/Mexico


Monica Missrie coordinated the Monarch Program for World Wildlife Fund 1999-2001

In support of Mexico's environmental authority, World Wildlife Fund (WWF) has helped design an innovative conservation scheme to protect and restore the unique high-altitude oyamel fir forest ecosystem which provides critical winter habitat for the Monarch butterflies (Danaus plexippus) of Canada, the U.S. and Mexico. A well-preserved, functional forest ecosystem in Mexico is critical to the survival of the monarch butterfly migration, which has been recognized as an endangered biological phenomenon, and the first priority in world butterfly conservation. This new conservation scheme, which includes a technical proposal for a new Monarch Butterfly Biosphere Reserve and the establishment of a trust fund to finance conservation incentives, is needed to preserve this forest ecosystem, home to one of the most remarkable natural phenomena in the world.

Monarch butterflies fly from Canada and the U.S. southward for up to 3,500 km and overwinter in Mexico for approximately five months without breeding. Then, at the end of March, they reach sexual maturity and survivors remigrate northward for an additional 1,500 km to the U.S. Gulf Coast states where they lay their eggs and die. The ensuing generation of adults continues the migration northwards into southern Canada and, over the summer, as many as three more generations are born. The annual migration cycle is completed when the adults born in the last summer generation begin the fall migration in late August and early September.


1.1 Location
The oyamel (fir) forests where the monarch butterflies overwinter are located in the western end of the State of Mexico and the eastern boundary of the State of Michoacán in Central Mexico. The area is considered a conservation priority site by Mexico's Federal Commission on Biodiversity (CONABIO) and is one of the Global 200 ecoregions identified by WWF as priority conservation sites: the Transvolcanic Belt of Central Mexico. This area is one of the three Mexican Sierra ecoregions whose main vegetation is a mixed pine-oak forest. Running east-west, this ecoregion includes the highest peaks in Mexico with elevations of up to 17,308 feet (Pico de Orizaba). The mountain tops are crowned with snow, alpine tundra, fir forests, and, further down hill, pine-oak forests. The oyamel forest of this ecoregion is one of the most severely threatened vegetation types in Mexico, with less about 50,000 ha. remaining (from an original extent estimated at 500,000 ha.).

1.2 Importance
Survival of the monarchs in Mexico from November through March depends on a delicate balance of macro and microclimatic factors that characterize the Oyamel Forest. This microclimate provides physical conditions that are: (1) cold enough to maintain the butterflies in a state of reproductive torpor, but not so cold as to kill them; (2) warm enough to maintain the integrity of their clusters, but not so warm as to result in excessive activity or premature sexual maturation; and (3) wet enough to prevent desiccation and forest fires, but not so wet and cold as to preclude all butterfly activity.

Herein lies the importance of the highly specialized Oyamel Forest Ecosystem: the watersheds of these forests also provide a highly specialized topography and microclimate that allows overwintering, but only within severe constraints that are totally dependent upon the fir forest being mature and undisturbed. Forest thinning is incompatible with successful monarch butterfly overwintering.

Because the Oyamel forests occur high on the mountains they provide a cool and humid environment for the butterflies. The trees serve as a blanket and umbrella protecting the butterflies from getting wet and freezing to death during winter storms (see figures 1 and 2).

Additionally, successful overwintering involves a dynamic utilization of the watersheds in the Oyamel Forest ecosystem. At the beginning of the overwintering season, butterflies begin using the upper watersheds, moving downward until their departure (see figure 3). These watersheds are not only important to the butterflies, but also to humans. Local communities depend on forest springs to cover their basic water needs during the six-month long dry season. In addition, these watersheds feed two large water systems that provide water to the local districts, Mexico City and other areas: the Temascaltepec and Rio Lerma water basins.

2.1 Background

In 1986, a Presidential Decree created the Monarch Butterfly Special Biosphere Reserve with an extension of 16,110 hectares. The decree included five conservation areas, one for each of the then known monarch overwintering sites. Each area, or sanctuary, contains a core zone, in which no logging is allowed, and a buffer zone, in which controlled logging may occur. Since its establishment, however, two main issues are defeating the objective of the reserve: continued and uncontrolled access to forest resources and the adequacy of the polygons as originally delineated.

As in most protected natural areas in Mexico, the establishment of the Monarch reserve in 1986 left land tenure in the area unchanged. Protection decrees limit the use of the resources in these forests, but do not include compensation of any kind, nor productive alternatives to their legal owners: the ejidos. Given the traditional economic dependence of ejidos on their forest resources, enforcement authorities are constantly confronted with a social challenge that often goes beyond their capacity and authority. As a result, continued resource demands on the protected forests are now threatening the ecological integrity of the oyamel forest and with it, the survival of the overwintering monarch butterflies.

2.2 Threats to the oyamel, pine-oak forest ecosystem

A quantitative study of aerial photographs taken in the monarch butterfly area in 1971, 1984 and 1999 shows the deforestation that has occurred in the area. An analysis of the 42,020 has.depicted on the vegetation maps (see figure 4) comparing the three years determined that 12, 225 hectares (44%) of an original 27,485 hectares of high quality forest were degraded between 1984 and 1999. The data also indicated that over this 28 year period the size of the largest track of high quality forest decreased from 27,100 ha. to 5,800 ha. and that the forest became highly fragmented. Thus, what in 1971 was nearly continuous high quality forest is now a series of islands with large spaces of degraded forest between them. Sustainable management of these forests will only be possible in the long-term if logging stops and the forest recovers, regaining contiguous areas.

From a manuscript in review by "Conservation Biology" titled "Quantitative changes in forest quality in a principal overwintering area of the monarch butterfly in the states of Michoacan and Mexico: 1971 to 1999"; Courtesy of World Wildlife Fund, Mexico, and the authors, L. P. Brower, G. Castilleja, A. Peralta, J. Lopez-Garcia, L. Bojorquez, S. Diaz, D.Melgarejo, and M. Missrie. 2001.




The annual rate of forest degradation from 1984 to 1999 was determined to be 2.41%. If degradation continues at this current rate, there will be less than 10,000 ha. of highly fragmented conserved forest patches remaining in 20 years, and in 50 years, less than 5,000 ha. will remain. As patches increase the chances for recovery decrease, endangering the survival of the forest ecosystem and its watersheds.

The results of this analysis indicate a serious danger of the oyamel ecosystem unraveling, with severe consequences for the biodiversity it hosts, including its most famous insect and for the local communities that depend on it. . This problem is well demonstrated in photographs taken in areas bordering the colonies (see figures 5 and 6). Associated with forest cover degradation, water shortages during the dry months are becoming more and more critical. Local inhabitants, especially women, consider water scarcity their main environmental problem.

Causes for this forest degradation are multiple, including excessive and illegal commercial logging, wood harvesting for domestic use, forest conversion to agriculture, and damage from periodic fires. The forest has been thinned excessively and has not had a chance to regenerate because the forest industry in the area demands low quality wood to produce particle board. Young trees are felled and processed in hundreds of sawmills in the area to supply producers with the wood chips they need for the particle board, thus increasing pressure on the forest. All these factors and the results of the vegetation analysis described above, show beyond a doubt that that these multiple negative effects on the oyamel forest ecosystem are incompatible with the needs of the monarch butterfly and, over the long term, those of the local inhabitants as well.

Protection of the overwintering sites of the monarch butterfly in Mexico is the most urgent conservation measure because of the rapid degradation of the Oyamel forest ecosystem. However, the monarch is also endangered in its spring and summer breeding range and along its migratory routes in Canada and the United States. Monarchs have two major food requirements during their life cycle, and both are seriously threatened by current industrialized agriculture. Millions of acres of corn and soybean fields in the heart of the monarch's breeding grounds are sprayed with poisonous herbicide chemicals that kill all plants, including the native wildflowers from which monarch adults must drink nectar and vast numbers of wild milkweed plants, the only food monarch caterpillars are able to eat. In addition, the recent use of a genetically engineered corn was discovered to have an unanticipated side effect: pollen grains from the corn blow onto the milkweed leaves and can kill the monarch larvae. Because of the vastness of industrialized agriculture in the US and Canada, both countries need to cooperate with Mexico for the long-term survival of monarch butterfly migration in North America.

2.3 Addressing the threats

Aware of the multiple challenges facing the region and as a result of the issues discussed during the tri-national North American Conference on the Monarch Butterfly sponsored by the Commission for Environmental Cooperation held in Morelia, Michoacan in November, 1997, SEMARNAP (the Mexican Ministry for the Environment, Natural Resources and Fisheries), through the National Ecology Institute of Mexico (INE) committed to review the 1986 Presidential Decree.

When the 1986 boundaries were established, critical biological information on the butterflies and the location of the colonies was limited. Consequently, the current polygons exclude important butterfly sites. Also, the shape and location of the polygons do not take into consideration the fact, only recently discovered, that the colonies form in and depend on the watersheds. This means that although the colonies form in the upper part of the watershed in November, they relocate downhill in February and emerge out of the gullies in late March, as they start the spring migration north. Therefore, protecting only the upper part of the watershed, as the original polygons intended is not sufficient.

In support of INE's commitment to review the 1986 decree, different institutions, including WWF, have dedicated scientific staff and personnel to this effort by developing a technical proposal for the redefinition of the boundaries of the protected area. This redefinition is based on up-to-date biological knowledge that has specified the minimum ecological requirements for successful overwintering of the monarch butterfly in Mexico

A proposal was presented to the federal environmental authorities in June 1999. Based on the proposal and taking into considerations critical land tenure and social issues, INE developed a new conservation scheme. The proposed new reserve represents a viable solution both from the standpoint of the monarchs, as well as for the economic wellbeing of the local people that will be directly affected by changes in land use.

The new reserve covers an area of nearly 56,259 ha, of which 15,306 ha make up the core area and 40,953 ha the buffer zone. This new core area is not limited to the specific overwintering sites, but includes larger, contiguous forest areas defined by a the inclusion of specific high priority adjacent watersheds. This scheme provides corridors between the different colonies, and also provides alternative safety sites where colonies can establish themselves, should their preferred watersheds become damaged by fire or any other agent.


Long and careful consideration of the problems of the current conservation scheme led INE to accept the need to compensate the ejidos who still have logging permits and whose land is within the proposed new core area. While, in theory, the government could expropriate ejido land, the measure is politically and socially unviable. Local communities include indigenous groups who have had to confront the different political systems for centuries to maintain the rights to their lands.

Other means for effective forest conservation needed to be devised. One central component will be monetary compensation for the loss of income from logging. In fact, this compensation, over the long term, would be an equivalent to payments for conservation. Additional instruments that can relieve pressure on the forest include direct investment by the federal government in alternative activities, economic incentives for conservation of designated areas, income-generation from sustainable tourism and stricter law enforcement, among others.

WWF and the Fondo Mexicano para la Conservación de la Naturaleza (FMCN) are collaborating in the establishment of a trust fund to provide the necessary financial resources to support long-term conservation activities by the local communities within the core zone of the new reserve. For the first time in the history of Mexico, a conservation trust fund will be created specifically to offer incentives to local communities affected by the establishment of a protected area, making them integral participants in conservation and sustainable use activities.

The proposal centers on a trust fund as a mechanism to generate sustained annual income to compensate communities for the short-term loss of income from logging. Over the medium-term, the funds generated by this mechanism will gradually shift and provide economic incentives to transform land use and the economy of the area from unsustainable logging to conservation and sustainable forest management.

The Monarch Butterfly Conservation Fund (MBCF) will finance the purchase of the logging permits currently operating inside the new core area of the proposed Monarch Butterfly Biosphere Reserve. In addition, the fund will provide payments for forest conservation activities included in the Management Program of the Reserve that will be carried out by local communities in the core zone. Both payments will be financed with the interest earned by the fund, through two main instruments: a capital fund and a disbursement fund. WWF and FMCN are currently negotiating donations with U.S charities for approximately five million dollars for the capital fund.

Specifically the fund will finance:

1. The purchase of the logging permits currently operating inside the new core area of the proposed Monarch Butterfly Biosphere Reserve;

2. Forest conservation activities, by local communities included in the management program of the Reserve; and

3. Promising economic activities promoted by local communities, compatible with the conservation objectives of the Reserve.

Sustainable tourism is one of the most promising economic activities. it is currently practiced from November to March, during the butterfly season. However, it lacks infrastructure and each year larger and less controlled crowds visit the relatively small sanctuaries. Furthermore, only the ejidos where butterfly colonies are present collect visitor entrance fees. There is no well-defined strategy to manage tourism for the benefit of the entire area and the conservation of the ecosystem. The monarch butterfly conservation fund can serve as the mechanism to distribute entrance fees equally among all the ejidos within the reserve, thus promoting integrated ecosystem conservation. There is great economic and conservation potential in a well-designed and implemented tourism strategy for the entire region.

Linking a compensation mechanism or an economic incentive system to the declaration of a protected area is an innovative concept in Mexico. Historically, land use limitations imposed by protected areas have given few options to land owners, unintentionally generating illegal resource use and social conflicts. Redefining the protected area of the monarch overwintering sites and offering a compensation scheme to land owners presents a unique opportunity to change the way protected areas are established and managed in Mexico.


As part of the laws regarding protected area management, no forest exploitation activities will be allowed in the core area. Enforcing this rule has been a problematic issue as illegal logging has been rampant. A recent study shows that timber taken out of the forest is double the legal amounts authorized by SEMARNAP. The majority of local campesinos want to see an end to illegal cutting, which benefits only a few. Also, women are concerned about the diminishing water supply. These issues are addressed in the proposal for the new reserve which includes conservation incentives for the local population and the promotion of sustainable economic alternatives. As unsustainable logging activities are gradually phased out, the area will be conserved, providing permanent, long-term benefits for the local population. Among these are a reliable water supply, income from sustainable tourism activities and non-timber forest products, as well as payments for ecological services that a healthy forest provides (water, carbon capture, soil conservation, maintenance of biodiversity).

Reactions against the proposed conservation scheme are expected from different affected parties. Most noticeable will be the opposition of the local timber industry through their associates in the local communities. They will claim that the proposed scheme limits local communities' access to their forest resources, on which they depend for their livelihood. While recognizing that the scheme involves a compensation payment, they will see it as insufficient compared to what they receive for their wood in the local markets. This, of course, is a problem of short- versus long-term perspectives. In any case, WWF and FMCN will continue working to increase the capital fund and make the scheme more attractive, even to the local loggers.

During the past three months, SEMARNAP carried out a negotiation process with the local landowners to explain the purpose of enlarging the reserve and the support programs they will implement, along with the WWF-FMCN proposal (payment for permits and conservation services as explained previously). The communities have expressed their concern in terms of the size of the new reserve, the amount they will receive for their permits and conservation services and the lack of information regarding the new reserve and proposed projects. In response, SEMARNAP is preparing an information package and a communications campaign.

Figure 1:Forest with clusters on oyamel tree (Ref. 83)
Figure 2 Frozen monarchs (Ref. 656)
Figure 3: Monarchs drinking water (Ref. 114)
Figure 4: Deforestation map
Figure 5: Colonies on edge of agricultural fields (Rosario) (Ref. 500)
Figure 6: Chincua deforestation sequence (Refs. 76, 511)
1 Eighty percent of Mexico's forest is owned by rural cooperatives known as ejidos. According to Agrarian law, forest areas in ejidos cannot be sold and can only be used by the ejidatarios who in turn can sell forest products in the open market.

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