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Revisiting the "River of the Mother of God": Aldo Leopold's Symbol of Global Wilderness

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The River of the Mother of God, or Ri?o Madre de Dios in Spanish, extends from the base of the Andes Mountains through the Amazonian lowlands of southeastern Peru and northern Bolivia where it meets the Madeira River. This essay provides an update on the area as seen through the lens of geographic research, since Aldo Leopold wrote his short essay in 1924 on the river as a symbol of shrinking global wilderness.

Most readers of this journal need no introduction to 1909 Yale forestry graduate Aldo Leopold. Co-founder of numerous conservation movements, pioneering founder of wildlife ecology and restoration ecology, and champion of the first officially designated wilderness area, Leopold is best known for his remarkably concise and prosaic essays in A Sand County Almanac, the most famous being “The Land Ethic.”1

Almost every reader of A Sand County Almanac has one essay that is a personal favorite. Mine is “Escudilla,” about a looming monolith of a mountain on the border of Arizona and New Mexico and the loss of its last grizzly bear. This story to me is intensely geographical in that it illuminates a sense and spirit of place. It also evokes a mixture of reflexive thinking about humans’ role in nature, touched with occasional levity: out on a ridge and you at once became a speck in an immensity. On its edge hung Escudilla...There was, in fact, only one place from which you did not see Escudilla on the skyline: that was the top of Escudilla itself... No one ever saw the old bear, but in the muddy springs about the base of the cliffs you saw his incredible tracks. Seeing them made even the most hard-bitten cowboys aware of bear. Wherever they rode they saw the mountain, and when they saw the mountain they thought of bear...We spoke harshly of the Spaniards who, in their zeal for gold and converts, had needlessly extinguished the native Indians. It did not occur to us that we, too, were the captains of an invasion too sure of its own righteousness. Escudilla still hangs on the horizon, but when you see it you no longer think of bear. It’s only a mountain now.2

Leopold is well known for these essays formed by experience in the US Southwest early in his career. Yet he also wrote about other places in “Latin” America, if we accept the US Southwest within Joel Garreau’s liberal boundaries of that region.3 Some of these locales were just across the US-Mexican border, in the Colorado River Delta of Baja and Sonora (“Green Lagoons”), or the Rio Gavilan of Chihuahua (“Song of the Gavilan” and “Guacamaja”). These three essays, along with “Clandeboye” set in Manitoba, Canada, helped add international perspective to A Sand County Almanac. Yet we must turn to other works by Leopold to find one of his most concise and insightful essays on our relationship to the condition of global wildlands.

South American exploration

“The River of the Mother of God” was written in 1924 when Leopold was well into his career in the US Southwest, formalizing in that year the world’s first official wilderness area within the Gila National Forest, primarily for recreational purposes. The short piece was actually rejected by the Yale Review, a literary magazine. Noted Leopold scholars J. Baird Callicott and Susan Flader, while going through a collection of previously unpublished Leopold writings, brought the “yellowed, slightly edited typescript” from the depths of Leopold’s archives for the first time. The editors were so enamored with the essay they also made it the title of the 1991 collection.4

From an early age Leopold was interested in global exploration. One of his favorite books in preparatory school was A Naturalist’s Voyage Around the World by Charles Darwin.5 No doubt Leopold would have loved, and may have even read, Humboldt’s journals about 19th century travel in South America. “The River of the Mother of God” shows Leopold’s fascination with deep time, geographic setting, and the unique character of wilderness travel to “unknown places”:

The river has been in my mind so long that I cannot recall just when or how I first heard of it. All that I remember is that long ago a Spanish Captain, wandering in some far Andean height, sent back word that he had found where a mighty river falls into the trackless Amazonian forest, and disappears...ever since some maps of South America have shown a short heavy line running eastward beyond the Andes, a river without beginning and without end, and labeled it the River of the Mother of God...

That short heavy line flung down upon the blank vastness of tropical wilderness has always seemed the perfect symbol of the Unknown Places of the earth. And its name, resonant of the clank of silver armor and the cruel progress of the Cross, yet carrying a hush of reverence and a murmur of the prows of galleons on the seven seas, has always seemed the symbol of Conquest, the Conquest that has reduced those Unknown Places, one by one, until now there are none left.

...I know the time is not far off when there will no more be a short line on a map, without beginning and without end, no mighty river to fall from far Andean heights into the Amazonian wilderness, and disappear. Motor boats will sputter through those trackless forests, the clank of steam hoists will be heard in the Mountain of the Sun, and there will be phonographs and chewing gum upon the River of the Mother of God. 6

So what has become of this Unknown Place of South America (Figure 1) in the 85 years since Leopold’s essay? In the spirit of addressing deep time, as Leopold often does, let us take a look back before 1924 to get long-term perspective on its status.

Deep time and place

Over the millennia, including periods of climatic warming and glacial cooling, the western Amazon is thought by paleobotanists to have acted as a refuge for species. This, combined with the steep gradient of the Andean range formed by plate tectonics, and the subsequent deposition of nutrient rich soil in lower elevations, has produced a landscape of remarkable biological productivity and species diversity.7
Geographer William Denevan conducted research deep in the Brazilian Amazon that has revealed, rather than a non-human “pristine” rainforest, evidence of an unexpectedly long human history, even in the most remote locales.8 Known human history in the Rio Madre de Dios region includes the Incas, who early in the second millennium extended communication networks of their empire down slope to the Amazon Basin. The ancient Incan capitals of Machu Picchu and Cuzco lie on the 15,000 foot “Mountain of the Sun” that Leopold refers to, less than 150 miles west of the Rio Madre de Dios as the crow (or macaw) flies. More localized tribes include the Yura and the Machiguenga, who speak an Arawak language similar to those found in the Caribbean when Columbus arrived.9

The conquest that Leopold refers to occurred as early as 1567, when Maldonado claimed the area for Spain. However, due to disease and the resistance of hostile tribes (including the Machiguenga), the Spanish struggled to control Peruvian Amazonia. More remote Machiguenga can still be daunting to visitors today; some practice traditional ethnobotany and slash and burn agriculture, while others work in modern industries and receive vaccination and schooling. Many of the Machiguenga did not receive their first contact with Westerners until the 1960s, more than three decades after Leopold’s essay. They have an estimated total population of over 10,000. Since the 1970s, many have moved to permanent settlements abandoning traditional, temporary slash and burn agriculture.10 There are still un-contacted natives in Madre de Dios.

Leopold provides some clues to local resource extraction, mingled perhaps with a measure of irony and remorse, when he writes:

I am conscious of a considerable personal debt to the continent of South America...It has given me, for instance, rubber for motor tires, which have carried me to lonely places on the face of Mother Earth...11

Charles Goodyear developed the process to produce rubber from trees in 1839. By 1880, Peru was exporting 8,000 tons of rubber annually and this number more than tripled by 1900. The Rio Madre de Dios area acted as a primary source. The 1982 Werner Herzog film “Fitzcarraldo” is a fictional elaboration of the attempts of a Peruvian rubber baron, Carlos Fermi?n Fitzcarrald, to create a passage between two watersheds to allow easier water transport of rubber from the Madre de Dios area in 1890. As soon as 1915, however, competition from Southeast Asian sources led to the decline of rubber export from the Madre de Dios area.


Leopold would likely be delighted to know that the biological richness of the area became a prominent focus in the latter half of the 20th century. Peru signed an agreement with other American nations in 1967 to establish parks to conserve regional flora and fauna, including “every biotope from the riverside forests of the Amazon’s main tributaries.”

The next year much of the upper Rio Madre de Dios area became a National Reserve, and in 1973 the area was designated Manu National Park, named after the upper tributary, the Manu River. A local resident, Celestino Kalinowsky of Quince Mil, played a major role in its establishment. An even larger area (4,648,546 acres or 1,881,200 hectares) is now designated as Manu Biosphere Reserve, which incorporates human land uses within sensitive buffer zones around preserved areas. Manu National Park, like many protected areas in developing nations, is set up differently than US national parks. The Park itself includes indigenous tribes and wildlife that is hunted by them. The Manu Reserved Zone outside the Park contains ecotourism and hunting restrictions that result in more tame wildlife that is more easily observed by travelers. A third part of the Biosphere Reserve, the Manu Cultural Zone, incorporates human settlement.

The River of the Mother of God is no longer such an “Unknown Place,” but for positive reasons Leopold could not predict. Rio Madre de Dios is today a highly research locale. Botanical publications from the area alone number 492, accomplished through approximately 50,000 plant collections since the late 1800s.12 Nigel Pitman’s recent study found a remarkable total of 2,202 publications have been written on the area in the past 450 years.13 After initial efforts by local Celestino Kalinowsky, Duke University professor John Terborgh has provided much of the scientific foundation for biodiversity assessment since 1973, working out of the Cocha Cashu Biological Station.14 Results of various studies are striking, leading to some to believe that the Rio Madre de Dios area may well harbor the highest species diversity on the planet.

Flowering plant species in Manu National Park are believed to number from 5,000 to 15,000. The Park is roughly the size of the state of Connecticut, which by comparison has approximately 2,600 plant species. Manu hosts approximately 1,000 bird species and more than 200 mammal species (about half of which are bats). The only park in South America to rival these species numbers is Madidi National Park, just over the border in Bolivia.15

The Botanical Research Institute of Texas (BRIT) has recently conducted five years of continuous field studies outside the Park, including training of locals and systematic transects, which contrasts with shorter-term studies of other programs. Partly due to methods and partly due to site differences at the 400,000 acre Los Amigos Conservation Area, the BRIT program has in some cases come up with
twice as many species as other studies. Plant species at their site number more than 2500, with 510 species of wetland plants. Tree species alone number approximately 1500, while fern species number 208.16

Leopold was remarkable in his perception of issues long before they became prominent in natural resource management. Issues he noted, well before others did so, include, but are not limited to: the relationship of increased grazing to fire suppression, brush encroachment, and increased soil erosion in the arid Southwest; the mixing of genetic stocks of trout in the US West, causing loss of locally adapted species; and the link between predator removal and deer population explosions (irruptions). Could Leopold also have had some intuition that the Rio Madre de Dios, this “Unknown Place,” is among the most biologically diverse places on the planet? There is no clear evidence to support that, although at the time it was fairly common knowledge among biologists—thanks in no small way to Darwin and Humboldt—that the tropics did contain more species than temperate biomes.

Good roads?

Unfortunately, one thing Leopold did predict accurately is the next chapter in the history of The River of the Mother of God. Again, at the time Leopold was promoting wilderness for its unique recreational value, and the second half of his essay is devoted to criticism of the transportation infrastructure that destroys this:

The thing that is choking out the wilderness is not true economics at all, but rather that Frankenstein which our boosters have built, the “Good Roads Movement.” This movement, entirely sound and beneficial in its inception, has been boosted until it resembles a gold-rush, with about the same regard for ethics and good craftsmanship. The spilled treasures of Nature and of the Government seem to incite about the same kind of stampede in the human mind.17

Leopold in this passage is specifically referencing the forces at work in the forests of the US Southwest (and beyond). South America is in many respects going through the same expansion Leopold was critiquing that occurred in the US West in the 19th and early 20th century. Rondonia, Brazil was widely publicized in the 1980s as an example of westward expansion for settlers that destroyed the rainforest. Such large projects are less prevalent now, and indigenous areas have more political protection, but the continent is currently in the midst of its own “Good Roads Movement.”

National Geographic journalist Ted Conover recently chronicled the construction of the East-West Amazonia Highway through the city of Puerto Maldonado, Peru, which adjoins Manu National Park and contains lower portions of the Rio Madre de Dios. Conover writes:

Like many in the developed world, I am enchanted by roadless places. The Earth has so few of them left, and glorious creatures like toucans depend on them. Many thoughtful people believe that the fate of the Earth itself depends on keeping nature unpaved.
But Peru is mad for new highways. Just as the north-south Pan-American Highway was the infrastructure project of the 20th century for South America, many people see an east-west Carretera Transoceanica—a road joining the Pacific to the Atlantic—as the project of the 21st. 18

Amazon Basin country takes up roughly half of Peru, yet only five percent of Peruvians live there. Improved road access could change those numbers. Yet the rationale is not so much settlement as profit and development from reduced transport costs, building a more traditional connection with the fast-paced global economy. Amazon goods could reach Pacific ports in two days instead of a week. What goods would they transport? Currently this could include timber (mahogany), gold, cattle, soybeans, and illegal wildlife. Harvest of each of these products has its own direct and indirect impacts in southeastern Peru.

Peru leads the world in mahogany exports. Up to 90 percent is logged illegally, with almost half of these exports going to the U.S. for furniture and coffins. Big- leaf mahogany is covered under the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Loggers make only six dollars a day. Their camps have impacts that may rival the actual logging, including hunting for bush meat and conflicts with indigenous communities.

The new Carretera Transoceanica (Trans-Amazon Highway) enabled gold miners to bring a thousand earth- moving machines to the unlicensed Huaypetue strip mine in the 1990s. The mine covers 40 square miles (100 square kilometers). Conover notes that “at the peak of the gold boom in 1998, some 2 percent of the world’s annual gold production may have come from this mine.” The mining does not employ local residents as much as it does tens of thousands of poor immigrants from the highlands, many of whom are exposed to mercury contamination. The most important impacts of Amazonian road building and improvement can be the unintended consequences of immigration, settlement, and forest clearing.

As the Peruvian government has recently leased oil and gas rights throughout its Amazonian region, drilling and pipeline supplies may soon be transported on the Transoceanica. While more sensitive oil and gas roads may be include restricted access and post-project closure, the pressure of poverty can still bring illegal settlement.

Recently indigenous tribes in northeastern Peru have rebelled against these leases, leading to violence covered in global news.19 The Peruvian government claims the tribes do not have rights to special benefits from oil and gas leases, the revenue should be shared among all Peruvians. The tribes protest that the leases threaten biological diversity and cultural integrity.

“Deep” future – unintended consequences

Eighty-five years ago Aldo Leopold considered deep time along the Rio de Madre de Dios. It is apt now to inquire about the “deep” future. What will become of the River of the Mother of God over the next eighty-five years? Will its rich biodiversity still signify the area in 2094?
Clearly, the present scale and rate of impacts are well beyond the rubber tapping of the 1890s, from which the Rio Madre de Dios recovered. Indirect impacts such as immigration, clearing, hunting, and indigenous conflict can rival the direct impacts of logging and mining. Although Manu National Park and Reserve are in place, “paper parks” are notoriously suspect to illegal encroachment throughout the developing world.

Father Paul McAuley, co-organizer of the Loreto Environmental Network in the Amazonian region of northeastern Peru, sees the issue as one of indigenous rights and official corruption. Without strong protection of indigenous land rights, with corresponding cultural protection, McAuley sees a future Peruvian Amazon as a “museum for native groups who acted in the past.”20

Illegal logging is one of the symptoms of this condition. Even though 20,000 cedar logs were stopped from export by CITES enforcement, the Peruvian government liberated them on the market without records. McAuley’s Network also won a case in Lima in 2006 to protect 700,000 hectares from new logging concessions that violated indigenous rights. By 2009, illegal logging was proceeding in the area: “there are powers much bigger than the legal system at work.”

A new free trade agreement exists between the US and Peru. Although a forestry chapter exists in the agreement, the primary goal of the Peruvian government is to open the country to investors so they can work with minimal problems. McAuley believes “The challenge is to have management that includes locals as actors, not just workers...World Bank aid can’t go to corrupt governments like Peru.”
McAuley suggests that payments for ecosystem services to mitigate climate change should go to the local people in these locales, not federal governments, to ensure forest protection. He puts the responsibility on the markets, many of which are driven by the US: “The moral weight now is with the United States and those who claim they care about democracy, those who care about climate change, to put pressure on the Peruvian government.”

Leopold, at the start of his essay, also suggests responsible relations with remote, wild South America:

I am conscious of a considerable personal debt to the continent of South America. It has given me, for instance, rubber for motor has given me has given me rare woods, pleasant fruits, leather, medicines, nitrates to make my garden bloom, and books about strange beasts and ancient peoples. I am not unmindful of my obligation for these things. But more than all of these, it has given me the River of the Mother of God. 21

Our new US administration promotes change and has a full agenda of projects to implement it, including efforts involving Afghanistan, Iraq, health care, and economic recovery. With regard to Latin America, President Obama remarked about the recent coup in Honduras:22 “We do not want to go back to a dark past,” in which military coups override elections... “We always want to stand with democracy.”

One of the current projects of the Center for Humans and Nature is to investigate the role of democracy in environmental protection. Fareed Zakaria’s recent book warns against simple political solutions, and cautions that democracy may not be a global panacea.23 Indeed, the two major forces that have reinvigorated the field of geography in recent decades are: (1) technology, allowing more sophisticated analysis through the use of computerized geographic information systems, remote sensing, and global positioning systems (see Figure 2)24; and (2) political ecology, a mode of inquiry that allows for more sophisticated analysis through examination of not just the symptoms of globalization, but the drivers and influences of change, many of which lie in remote places and policies.25

An example of remote influence is the global soybean crop. Rising ethanol prices recently caused US farmers to grow more corn relative to soybeans. The global soybean market was met by Brazilian farmers increasing their soybean production, thus increasing their acreage within former Amazonian forest habitats. Such unintended consequences are a recurring theme within the research agenda of political ecology.

Another example of surprising results is support for birth control among indigenous tribes within Amazonian reserves, a seemingly logical goal of remote, environmental NGOs seeking to stabilize the incidence of slash and burn agriculture in areas of high biodiversity. However, the result of increased access to contraceptives was twofold: (1) indigenous women used them to space out births, leading to healthier babies and ultimately larger families; and (2) despite this, the larger population did not lead to direct impacts, as many in the growing population sensed lack of space and migrated to earn cash. The larger, more educated indigenous population gained increased political power to protect their reserves from encroachment by non-natives.26

Stephen Perz’s research just across the border in Brazil also illustrates the complexity of spatial drivers of road- building in the western Amazon. Climate change adds pressure to traditionally mobile Amazonian tribes, such as the remote Macheguenga and interior Brazilian groups, who now have less territory to adapt in.27

Fortunately, several organizations and researchers are addressing indigenous land rights in the western Amazon. Alaka Wali of the Field Museum of Chicago is investigating the effects of protected areas on indigenous communities. Other anthropological work in the region includes foundational work by Glenn Shepard on the Machiguenga and more recent work by Rick Stepp and Marianne Schmink. Efforts to use ecotourism to empower local, semi-modern tribes, through Charles Munn and others, have had some success.28 The NGO InkaNatura is deeply involved in this activity. Perhaps the most effective organization for local indigenous land rights in Peru is the Centro para el Desarrollo del Indigena Amazonico (CEDIA), which has worked to gain rights to 500,000 hectares for 30 Machiguenga communities. Conrad Feather, co-organizer of the NGO named Shinai (NGO), also won a prestigious St. Andrews prize for his work on indigenous land rights for the Machiguenga.

World Wildlife Fund (WWF) contacts for the area include Mariana Panuncio, Senior Program Officer; George Powell, Senior Conservation Scientist working with reserve design in the southwestern Amazon; and Rodrigo Tello, a graduate student with the University of Maryland. More broadly, senior scientist Michael Mascia of WWF leads a social science movement within biodiversity conservation through the Society for Conservation Biology’s Social Science Working Group, which highlights research in this growing and critical arena. Human-wildlife conflict researcher Tara Teel is their newest president.

Despite the abundance of research and organizations addressing this formerly “Unknown Place,” they still have limited power in the context of Peruvian national sovereignty. Given the complexity of people and politics in biodiversity issues, a cursory analysis of the Rio Madre de Dios suggests “standing with local democracy” in the Peruvian Amazon could mean promoting the bottom-up policies that so many organizations are adopting globally, including the Border 2012 program29 and the World Bank project in the Chaco region of Colombia.30 While many movements are calling for change, in strongly suggesting to Peru that its indigenous communities retain control over their environment, the Obama administration likely has an opportunity for one of its greatest environmental accomplishments in supporting such movements.

This is not just a matter of importance within the time frame of a four-year presidential term, a century, or even the history of a nation. As Richard Leakey states in The Sixth Extinction, it is important within the time frame of the history of the planet. We are the first biological agent of a mass extinction. One of the main premises of “The Land Ethic” was Leopold’s call for humans to become “plain citizens” of the biotic community, one of many species. There is perhaps no better place to contemplate this thought than in a river basin he wrote fondly of, home to more species than anywhere else on earth.

Leopold warned in a 1944 essay, “Green Lagoons,” about his 1922 visit to Mexico’s Colorado River Delta: “It is part of wisdom never to revisit a wilderness, for the more golden the lily, the more certain that someone has gilded it.” He was correct in this case. Upon visiting the Delta in 2002, Aldo Leopold Foundation director Buddy Huffaker and I found Leopold’s “milk and honey” wetlands wilderness to be largely overtaken by non-native tamarisk, and occasionally burned over in crown fires that blackened the monocultural landscape. Cienega Santa Clara, the healthiest remnant wetland, was fed not by a natural, continental-scale river, but by a canal diverting water from a desalinization plant in Arizona that was too costly to operate. Conservationists were struggling with US powers to obtain a mere 1% of the Colorado River’s flow to support wetlands and associated delta species.

Leopold attempted to set aside another Mexican wilderness, the Rio Gavilan in Chihuahua, as a control for healthy land in a proposed continent-wide study of deer population explosions. It was here that Leopold “first clearly realized that the land is an organism, that in all my life I had seen only sick land, whereas here was a biota still in perfect aboriginal health.” Leopold’s proposed research with renowned University of California-Berkeley geographer Carl O. Sauer never materialized in the late 1930s and early 40s, likely due to the looming priorities of World War II. The Rio Gavilan today, although in many respects still in moderate condition, is highly altered through post- World War II grazing, logging, and subsequent soil and stream erosion.31 Of the three outstanding Latin American wildlands Leopold wrote of, the Rio Madre de Dios has perhaps the best chance to preserve a biota “still in perfect aboriginal health.”

Conclusion - remote responsibilities

J. Baird Callicott and Susan Flader note that one reason Leopold’s land ethic and other writings were revolutionary is that they were not based merely on a visual esthetic that had supported our early national parks movement. Rather they were based on:

a refined taste in natural objects, and esthetic cerebral as it is perceptual...For him, the esthetic appeal of country, in other words, has little to do with its adventitious colors and shapes – and nothing at all to do with its scenic and picturesque qualities – but everything to do with the integrity of its evolutionary heritage and its ecological processes...Thus, as one consequence, Leopold is able to appreciate esthetically country that he has never seen but only imagined. In “The River of the Mother of God,” for example, he reflects on an unexplored river in the wilds of Amazonia.32

Most of us will never see the Rio Madre de Dios, yet we can appreciate, through Leopold and others, its unique place on the planet. Indeed, the U.S. urban population had just gone above 50% for the first time in the 1920 census (by 2000 it was 78% urban), and its total population had just gone above 100 million in 1915. Urban sustainability efforts such as green building and open space planning are now proliferating globally.

Yet this cannot replace the critical concern for places where impacts are greatest, these still-remote locales with an “integrity of evolutionary heritage” like the Rio Madre de Dios. Despite demographic and scientific changes, Leopold’s land ethic is still highly relevant today,33 especially when properly negotiated with, and nurtured by, local, indigenous environmental ethics, rather than imposed universally.34 Whereas the sustainability movement calls for extending our ethics to future generations, global warming (regardless of the level of human influence in warming) and the scale and scope of global ecological drivers adds to this responsibility, with a call for extension to those newly understood, remote locations that are experiencing unprecedented changes.

Back in Peru, the Botanical Research Institute of Texas has moved their research efforts from the rich Los Amigos riverine wetlands area to a more elevated site in the watershed near Quince Mil, on the road from Puerto Maldonado to Cuzco. This new location allows for the study of tropical rainforest and cloud forest, including habitat of the Andean spectacled bear. Unlike the grizzly of the essay Escudilla, the spectacled bear is a gentler citizen of the cloud forest. Such creatures invite affection through comical movements, joining the comedic ranks of the sloth, otter, tapir, macaw, and Leopold’s thick-billed parrot of Mexico. It’s almost as if evolution had looked into the future to read Strachan Donnelly’s call for levity in environmental issues.

Escudilla Mountain is thousands of miles away from Peru. Nonetheless, I think we can understand that, without the spectacled bears and their fellow members of to surrounding biological community, the Rio Madre de Dios in another eighty-five years will not be a place of deep evolutionary heritage and ecological process. It will just be a river.


1. Leopold, A. 1949. The Land Ethic. In, A Sand County Almanac and Sketches Here and There. New York: Oxford University Press.

2. Leopold, A. 1949. Escudilla. In, A Sand County Almanac Sketches Here and There. New York: Oxford University Press.

3. Garreau, J. 1981. The Nine Nations of North America. Boston: Houghton Mifflin.

4. Leopold, A. 1991. The River of the Mother of God and Other Essays by Aldo Leopold. J. B. Callicott, S. Falder, eds. Madison: University of Wisconsin Press.

5. Meine, C. 1988. Aldo Leopold: His Life and Work. Madison: University of Wisconsin Press.

6. Leopold, A. 1991. The River of the Mother of God. In, The River of the Mother of God and Other Essays by Aldo Leopold. J. B. Callicott, S. Falder, eds. Madison: University of Wisconsin Press.

7. Colinvaux, P. 2007. Amazon Expeditions, My Quest for the Ice- Age Equator. New Haven, CT. Yale University Press.

8. Denevan, W. 1992. The Pristine Myth: The Landscape of the Americas in 1492. Annals of the Association of American Geographers, 82 (3): 369-385.

9. Munn, C. 1997. “Conservation Efforts in Manu and Cooperation with Local Peoples.” Living Edens Series. Public Broadcasting System (PBS online): manu/

10. Shepard, G. 1997. “The People of Manu.” Living Edens Series. Public Broadcasting System (PBS online): http://www.

11. Leopold, A. 1991. The River of the Mother of God.

12. Munn, C. 1997. “Conservation Efforts in Manu and Cooperation with Local Peoples.” Living Edens Series. Public Broadcasting System (PBS online):

13. Pitman, N. C. A., M. Del Carmen Loyola Azaldegui, K. Salas, G. T. Vigo, D. A. Lutz. 2007. Written Accounts of an Amazonian Landscape Over the Last 450 Years. Conservation Biology Volume 21, No. 1, 253-262.

14. Terborgh, J. 1990. An Overview of Research at Cocha Cashu Biological Station. In, Four Neotropical Rainforests. Gentry, A.H., ed. New Haven: Yale University Press.

15. Munn, C. 1997. “Conservation Efforts in Manu and Cooperation with Local Peoples.” Living Edens Series. Public Broadcasting System (PBS online): manu/

16. Botanical Research Institute of Texas. 2006. Andes to Amazon Biodiversity Program. Fort Worth: http://www.andesamazon. org/

17. Leopold, A. 1991. The River of the Mother of God.

18. Conover, T. 2003. “Peru’s Long Haul: Highway to Riches or Ruin?” National Geographic, (6): 80-99.

19. BBC. 2009. Peru army call for Amazon protest. May 17th,

20. TRAFFIC South America (wildlife trade monitoring network). 2009. Voices of the Amazon: Paul McAuley. June 11th.

21. Leopold, A. 1991. The River of the Mother of God.

22. Cooper, H., M. Lacey. 2009. “In a Coup in Honduras, Ghost of Past U.S. Policies.” New York Times, June 30th.

23. Zakaria, F. 2003. The Future of Freedom: Illiberal Democracy at Home and Abroad. New York: W.W. Norton and Company.

24. Scott, M. 2007. Remote River Reconnaissance: Space Shuttle Observations Help Conservation Biologists. NASA’s Earth Observatory:

25. Robbins, P. 2004. Political Ecology: A Critical Introduction. Malden, MA: Blackwell Publishing.

26. McSweeney, K. 2005. Indigenous population growth in the neotropics: social science insights for biodiversity conservation. Conservation Biology. Vol. 19, no. 5: 1375-1384.

27. Rosenthal, E. 2009. An Amazon Culture Withers as Food Dries Up. New York Times, July 28th.

28. Cauper Pinedo, S. 2001. Participacion de las Comunidades Indígenas Amazónicas en el Desarrollo de las Actividades Ecoturisticas. In, Proceedings of the first international congress of biodiversity, 24 a 28 Septiembre de 2001, Cusco, Peru. Bussmann, R.W., S. Lange, eds. Munich, Germany: INKA, e.v.

29. Zorc, E. 2004. Border 2012 US-Mexico Environmental Program: Will a Bottom Up Approach Work? Georgetown International Environmental Law Review, Spring issue.

30. Offen, K.H., 2003. The Territorial Turn: Making Black Territories in Pacific Colombia. Journal of Latin American Geography 2 (1): 43-73

31. Forbes, W. 2004. Revisiting Aldo Leopold’s Perfect Land Health: Conservation and Development in Mexico’s Rio Gavilan. Ph.D. Dissertation. Denton, TX: University of North Texas.

32. J. B. Callicott, S. Falder, eds. Introduction. In, Leopold, A. 1991. The River of the Mother of God and Other Essays by Aldo Leopold. Madison: University of Wisconsin Press.

33. Callicott, J. B. 1996. Do Deconstructive Ecology and Sociobiology Undermine Leopold’s Land Ethic? Environmental Ethics, 18 (1): 353-72. Callicott, J. B. 2000. Harmony Between Men and Land: Aldo Leopold and the Foundations of Ecosystem Management. Journal of Forestry, 98 (5): 5-13.

34. Evanoff, R. 2007. Bioregionalism and Cross-Cultural Dialogue on a Land Ethic. Ethics, Place, and Environment: A Journal of Philosophy and Geography, 10 (2): 141-156.

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