Introduction -- Motivation Statement

"... living things must compete with each other for space and resources; yet each organism also depends symbiotically on the well-being of the whole for its own survival and well-being. Indeed the welfare of all organisms -- including human beings -- is causally dependent on the health and stability of the ecosystems which sustain them. As a consequence, the stability and well-being of the Earth's biosystem has moral priority over the welfare of any of its parts -- including the needs and interests of human societies and individuals. " [Elliot, 1997]

The activities described in this document are motivated by this proposition. Manifestly, the stability and well-being of the Earth's biosystem is an immense topic, beyond treatment by any individual study. The concept does, however, provide a lodestone that can guide an attempt to conform with Rene Dubos' celebrated dictum to, "Think globally, Act locally." In this case local action revolves around the mangrove forests in the San Blas municipality, Nayarit State, MEXICO. The map below shows the location of this area.

My interest in the mangroves developed slowly, beginning in 1988 when I first moved to San Blas. Over the next several years I spent many hours on the fringes of the mangroves, peering into their murky depths, observing their complexity, marveling at their productivity, and learning to appreciate their value to both the human and the wild life communities that surround and occupy them. I have also found a large body of literature concerning the value of mangroves which has confirmed my personal observation. I have encountered many lists that detail the beneficial effects of mangroves. The list below is typical:

A detailed discussion of these values can be found at, so I will not further discuss them here.

Another way to appreciate the importance of mangroves is to analyze the economic importance of their functions. The value of these functions are difficult to quantify, but Costanza et al. [1997. The value of the world's ecosystem services and natural capital. Nature 387, 253-260] have proposed a figure as high as US$9,990 per hectare per year in the United States. This number would be different in other socio-economic situations, but it illustrates that the value is quite large. This conclusion holds no matter where in the world mangroves are located. The economic theory of supply and demand leads to the further conclusion that this value will grow as mangrove ecosystems become increasingly scarce.

As I was learning to treasure the mangrove forest it became increasingly obvious that this resource is under tremendous pressure. This fact was driven home in 1994 when I returned to San Blas after a prolonged absence to find an enormous dragline just completing a drainage canal along the edge of one of my favorite bird watching sites. Over the next two or three years I observed large areas adjacent to this canal transform from a highly productive, richly diverse natural ecosystem which supported a vast array of wildlife into a monoculture grassland, dedicated to raising cattle, punctuated with artificial shrimp production ponds. This observation led me to the question, "What is the future of the mangrove forests in San Blas?"

I was not alone in posing this question. Many others in the community were also disturbed by these trends. The increasing community awareness became evident in 1993-1994 with the formation of an environmental interest group called El Grupo Ecologico "El Manglar." El Manglar coalesced largely as a reaction to two dramatic development proposals made by outside agents for the exploitation of local resources. The first was a proposal to develop a tourist "Mega-project" consisting of multi-story hotels, condominiums and private golf courses catering to the wealthy tourist backed by North American interests. The second was a massive shrimp aquiculture project initiated by a large Mexican commercial conglomerate. Both of these projects entailed enormous changes in the character of the local natural and social environments. A significant portion of the community felt that they were in danger of being exploited by outside forces over which they had little influence and from whose activities they expected to receive few benefits.

I joined El Manglar in the year 2000. The information presented here was collected in conjunction with the group's activities, primarily under the umbrella of a Secretaría de Desarrollo Social (SEDESOL) financed research project titled Diagnóstico Socioambiental de la Zona Estuarina y de Manglar del Municipio de San Blas, Nayarit (Socio-environmental Diagnostic of the Estuarine and Mangrove Zone of San Blas Municipality, Nayarit [Spanish Only]). This study was designed to obtain a baseline data set on the current state of the mangrove forest and the attitudes the people most closely associated with these forests have towards them.

The task is large, and much remains to be done. But all journeys begin with a single step. I both hope and believe that we have made a promising step in the direction of increasing the stability and preserving the well being of this extremely valuable part of the earth's biosystem.

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