The vast rainforest is an ecosystem without parallel. As deforestation and climate change threaten this primordial gem, scientists are making new discoveries and raising intriguing questions in a quest for future strategies. Maryann Bird joined an expedition in remote northern Peru.
“As any naturalist knows,” wrote the late British author and conservationist Gerald Durrell, “there is nothing like a tropical rainforest for replacing arrogance with awe.” Among nature’s last frontiers, rainforests are primordial places, dark and mysterious even in daytime. Alive with rarely seen flora and fauna, they are “one of the most complex, beautiful and important of the many ecosystems on this planet”.
They also are places, Durrell added, “that, primarily out of greed, we are destroying with the savage, unthinking ferocity of a troop of drunken apes in an art gallery. But whereas pictures can be repainted, tropical rainforests can’t be recreated, and at the rate we are destroying them this bodes ill for the future of the planet, for these vast forests are climate controllers, desert preventers and huge storehouses of as-yet-untapped natural resources.”
As their name suggests, tropical rainforests lie between the Tropic of Cancer and the Tropic of Capricorn – in southern Asia, northern Australia, Africa and Latin America -- within equatorial parallels around the planet where the sun is strong and the climate is warm, moist and stable. When it comes to inspiring wonder, though, the Amazon rainforest has no rival.
Diverse foliage in the rainforest
The Amazon river basin’s immense tropical jungle represents more than half of the earth’s remaining rainforests. Occupying 5.5 million square kilometres of the most species-rich forest tract anywhere, it is breathtaking in its biodiversity. Biologists estimate that within its wet confines, from the towering canopies of its trees to the forest floor, are millions of different living species. The basin itself is the world’s largest reserve of fresh water. Covering seven million square kilometres and spread over nine nations, it drains 40% of South America. Flowing eastward to the Atlantic, the Amazon system contributes one fifth of the world’s total volume of fresh water entering the oceans.
Across its vast green stretches and along its hundreds of muddy rivers, Amazonia appears primitive and timeless. Through its remoteness and sheer size, it is protective of its secrets – some of which are being revealed slowly as new plant- and animal-life discoveries are made. Yet the health of much of the rainforest is in jeopardy because of deforestation and climate change. As species vanish within the forest, in one archivist’s words, “we’re burning the books in the library of life before they’ve even been catalogued”.
Deforestation is being carried out -- both legally and illegally -- for logging, mining, industrial agricultural production and road building. But climate change – including rising levels of greenhouse gases in the earth’s atmosphere and increased instances of drought – may soon outpace deforestation as a threat to the Amazon and other tropical rainforests. (And scientists say that both climate change and deforestation contribute to the spread of malaria into new areas of the Amazon. Off-season rains and massive tree-clearing each result in sunlit, larvae-containing puddles of water that are ideal breeding grounds for disease-carrying mosquitoes – often in areas where malaria was not previously present.)
Understanding these processes, and what effect they and other societal and environmental trends are having, is occupying scientists across the Amazon. One area under study is isolated Loreto, the largest and northernmost of Peru’s administrative regions. Covering almost a third of Peruvian territory, densely vegetated and criss-crossed by rivers – most of them navigable – Loreto is little visited and sparsely populated. Indeed, so-called uncontacted tribes of indigenous humans still inhabit some of its forests.
For 16 days in July, I was part of a riverboat-based Earthwatch Institute expedition that set off from Iquitos, the Amazon River port city that is the Loreto region’s capital, to monitor wildlife populations in the Lago Preto Conservation Concession. This 10,000-hectare block of tropical forest sits on the upper Yavarí River, four days’ travel from Iquitos. The Yavarí, one of the Amazon’s many tributaries, divides Peru from Brazil along much of its length, and malaria is endemic in the area.
The vintage riverboat Ayapua, now used for research in the Amazon
Our 19-member Earthwatch team’s work turned out to be groundbreaking -- literally. Because journey time on the Amazon River was lost due to a mechanical problem aboard the main research vessel, the Ayapua, and then travel on the Yavarí was slowed by low water levels and tricky currents, we were compelled to stop short of Lago Preto to maximise the time for field research. Near the village of Macao, in the river’s mid-section, we opened up an entirely new research site.
Specifically, our international volunteer team was there to help Peruvian field scientists collect data on indicator species -- animals whose presence, absence or relative well-being is reflective of their ecosystem as a whole. Along the Yavarí, these species include pink and grey river dolphins, caimans, macaws, red uakari monkeys and other primates, giant river otters and forest-dwelling hoofed mammals, such as peccaries and tapirs. Accurately recorded findings on the diversity and population density of these animals are used in advancing community-based wildlife management, protected-area management and wildlife conservation policies.
The river dolphins (of which the pink are the largest species) are particularly instructive, dependent as they are on both abundance of fish and good water quality. They also are river’s top predators. Dolphins are not hunted in the Amazon, and there is a great taboo against killing them, even accidentally. The fish themselves also are critically important to the local people: sustainable use is tied to their socio-economic wellbeing as well as to the health of the ecosystem.
Lakes within the forest were formed by seasonal flooding and retreat of the river water, and pressure on them from commercial fishing is greatest on the Peruvian side of the Yavarí. With such fishing forbidden on the Brazilian side, which is protected indigenous territory, fishers from outside the immediate area – including some Colombians -- are descending on Peru’s Yavarí region. (Colombia has a sliver of frontage on the Amazon River, leading to the Yavarí; former Peruvian territory abutting Brazil, this southernmost bit of Colombia includes the port town of Leticia.)
The impact of bush-meat hunting – for game birds, peccaries, tapirs, monkeys and other animals -- also needs to be evaluated based on reliable data. “The only way to evaluate the success of wildlife management programmes is to monitor,” said Richard Bodmer, the Earthwatch project’s British principal investigator (chief scientist). “Quantitative data is critical. Without it, we wouldn’t have any backing for what we say.” Bodmer, a conservation ecologist at the University of Kent’s interdisciplinary Durrell Institute for Conservation and Ecology (DICE) -- named in recognition of Gerald Durrell’s lifelong commitment to conservation -- has been conducting research in the Peruvian Amazon for some 20 years.
At the new research site at Macao, the Ayapua -- a vintage riverboat from the rubber-boom era -- anchored beside a steep, muddy bank amid the flutter of numerous large, brilliantly hued butterflies. A week of field study soon began, with the understanding and approval of the local people. (One man even removed the shotgun trap he’d set up to protect his cassava patch from the ravages of large rodents known as agouti pacas.) The baseline data collected from this pristine site will be very important, says Bodmer.
On the river, with Peru on our right and Brazil on our left, we boarded small auxiliary boats at various times of the day and night, conducting data surveys of macaws, river dolphins and caimans. In the thick rainforest, machete-wielding field assistants cut three transects, each three kilometres long. Along these physically demanding trails, land-animal censuses took place. (Of particular interest to Bodmer was the presence of red uakari monkeys, a species that occurs only in certain areas of the Peruvian Amazon. The red-faced, bald primates have been found in their greatest number at Lago Preto. Seeing them at Macao, Bodmer said, was important and exciting because the rare monkeys’ territory is disjointed. “Why don’t they occur elsewhere where habitats are similar? Scientists don’t even have a good theory.”
Downstream, others volunteers recorded fish species (including red-bellied piranhas) in forest lakes. (This western area of the Amazon basin – an inland sea millions of years ago – is lower in altitude than its eastern equivalent. As such, the forest is muddier, more alluvial and often more flooded.)
A red-bellied piranha, known for its sharp teeth
The focus of wildlife conservation along the Yavarí (as along Peru’s Samiria River, where Earthwatch also sponsors work by Bodmer and his associates) is to help preserve Amazon communities. Solutions come through working with the local rural people, who understand the uses of fish, bush meat and other resources because they rely on them so heavily.
“Their grocery shops are their lakes, their forests, their gardens,” says Bodmer. Trees provide wood for boats and canoes, as well as house supports and charcoal for cooking; tree bark, too, has a variety of uses. The indigenous people know all too well that sustainability is a real issue, and the biologists are looking for interdisciplinary conservation mechanisms to help them better manage their resources for the long term. Land-use categories can be local (community-based), regional or national. “A hundred years ago,” notes Bodmer, “there wasn’t an issue of sustainability.”
While the local people are taking appropriate actions in many areas to safeguard the rainforest by using it sustainably, others still look to it for profit -- in timber, animal products or the illegal pet trade. Close to the river, there is no valuable timber left; it was cut down decades ago. Now, timber companies are busy deeper in the forest, taking selected species of tropical hardwoods, such as mahogany and cedar.
The logging is labor-intensive, however, and in this part of Peru the timber men need to float logs down streams to saw mills along the mouth of the Yavarí. This can take several months, sometimes up to a year. Unscrupulous companies, faced with the expense of paying and feeding loggers over the long periods of time that the work requires, often supply guns so the men can provide their own meat. Eventually, that hunting can adversely affect forest biodiversity. “By far,” says Bodmer, “the worst impact of the timber industry on biodiversity comes from the hunting.”
As part of the search for conservation solutions to bush-meat hunting, Bodmer and DICE have been working with the UK’s Darwin Initiative, the Wildlife Conservation Society (WCS) and Peruvian partners to certify pelts of peccaries, the wild Amazonian pigs killed for their meat. Communities that sustainably manage bush-meat hunting of wildlife species would be certified. Peccary pelts originating as byproducts of subsistence hunting – and so certified – then could be exported legally to European countries, where they are used in the manufacture of fine leather goods.
Under the Peccary Pelt Certification Project: “Certified communities would receive added benefits directly through an increased value of peccary pelts and indirectly through recognition of their conservation activities. This added value would act as an incentive for communities to convert unsustainable bush meat hunting practices to more sustainable hunting. Thus, the leather certification programme would bring economic benefits to rural families, improving their living standards, and at the same time help to conserve wildlife and Amazon forests. The added value would not increase hunting pressure, but would guarantee that bush meat hunting is sustainable, since any unsustainable increase in hunting would deem a community unfit for certification.”
The meat value of a peccary is much higher than the pelt value, says Bodmer, so “banning pelts won’t save one peccary.”
As in the cases of the peccary, the red uakari monkey and other unique Amazon species, he emphasises, “the monitoring is key, and we need to do more. We need a lot of people out there and a lot of activities. … Earthwatch has really helped us collect a lot more information than we ordinarily would have. This team opened up our eyes to the Yavarí. We need more trips to the middle Yavarí. We have to understand better what we need to do in helping formulate conservation strategies for the future.”
In the Amazon, the struggle for sustainability, the battle for biodiversity, continues.
Maryann Bird is associate editor of chinadialogue.
Homepage photo by Pierre Pouliquin