Tambopata National Reserve: River Forest, Biodiversity and the Madre de Dios

In south-eastern Peru, the Andes give way abruptly to the lowland rainforest of the Amazon basin, and two rivers, the Madre de Dios and the Tambopata, meet at the frontier town of Puerto Maldonado. South of the town, the Tambopata National Reserve protects more than a quarter of a million hectares of that forest and the rivers, oxbow lakes and swamps that run through it. It is one of the richest places on Earth for birds and butterflies, and it is also under real pressure. On Days 5 and 6 of our South American Small Group History and Culture Tour, the group flies from Lima to Puerto Maldonado and travels by boat along the Madre de Dios and Tambopata rivers to a rainforest lodge, spending two days in this river landscape.

The Tambopata National Reserve and the Madre de Dios rivers

The Madre de Dios River rises in the Cordillera de Carabaya of the Andes and flows east for more than 1,100 kilometres, past Puerto Maldonado and into Bolivia, where it joins the Beni. The Tambopata rises in the high Andes on the Peru–Bolivia border and descends through Puno into the lowlands. The two meet at Puerto Maldonado, at only about 256 metres above sea level.

Peru created the Tambopata National Reserve in September 2000. It covers 274,690 hectares, bounded to the north by the Tambopata and its tributaries and by the lands of three native communities, to the east by the Bolivian border, and to the south by the much larger Bahuaja-Sonene National Park, which extends into Puno. Together they form a large protected block with a shared buffer zone around them. Peru’s Congress had already declared the whole Madre de Dios region the “Capital of Biodiversity of Peru” in 1994.

Reading the rainforest from the river

River travel is the best way to understand this landscape, because the rivers shape almost everything around them. Lowland Amazonian rivers meander, carving away the outside of each bend and building sandbanks on the inside. Over time a loop can be cut off entirely, leaving a crescent-shaped oxbow lake, known locally as a cocha. The reserve’s management plan notes how much this varies between rivers: the Heath, on the Bolivian border, meanders constantly and leaves around 14 oxbow lakes for every 100 kilometres, while the straighter Tambopata leaves around four.

The rivers also rise and fall with the seasons. Rain falls heavily between December and March, with between about 1,600 and 2,400 millimetres a year, and the dry season runs from June to September, with transitional months either side. High water floods the lowest-lying forest; low water exposes sandbanks and muddy banks.

On the tour, the first experience of the forest is from the water: a boat journey of around half an hour from Puerto Maldonado along the Madre de Dios and the Tambopata to the lodge. The same afternoon, a second boat trip runs along the Tambopata at sunset. As dusk falls, naturalist guides scan the riverbanks with spotlights for caimans and other animals that become active at night.

Forest layers and habitat diversity

Away from the river, the forest varies more than first impressions suggest. Low-lying floodplain forest is reshaped by the river; higher terra firme forest, which never floods, carries some of the tallest trees. Among them is the Brazil nut, Bertholletia excelsa, which can reach 50 metres and rise above the surrounding canopy. Its story shows how connected the forest is. Its flowers are pollinated by large bees, and its seeds are spread mainly by agoutis, rodents with jaws strong enough to open the hard, woody fruit.

Brazil nuts are also an economy. Harvesting concessions covered roughly a tenth of the whole Madre de Dios region by 2011, a livelihood that depends on the forest staying standing, and dozens of harvesting contracts operate within the reserve itself. Elsewhere, great stands of native bamboo cover large areas of the south-western Amazon; each stand lives for around 27 or 28 years, then flowers and dies all at once.

That variety of habitats supports an extraordinary range of life. The reserve’s management plan records around 650 bird species, more than 100 mammals and more than 1,200 species of butterfly. Among the best-known birds are the macaws that gather at clay licks along the rivers, sometimes several hundred birds in a morning. Studies by the biologist Donald Brightsmith over more than 16 years suggest the main reason is sodium, which is scarce in the birds’ diet, rather than, as once thought, the clay’s ability to neutralise plant toxins. Visits peak in the breeding season, when chicks are in the nest, and most birds come in the early morning.

Will you see wildlife in Tambopata?

Almost certainly some, but nothing can be promised. Rainforest animals are often hidden by dense vegetation, and many are active at night or at dawn. Riverbanks and lakes are where wildlife is easiest to see; the tour’s river trips and the visit to Lake Sandoval give good chances of seeing caimans, monkeys and many birds. Rarer mammals are seldom glimpsed. The value of a naturalist guide lies as much in explaining the forest as in finding animals.

How should you watch wildlife responsibly?

Quietly and at a distance. Keep voices low in boats and canoes, never feed animals, and let the guide decide how close to approach. That matters most for sensitive species such as the giant river otter, which the IUCN lists as Endangered and whose family groups depend on quiet oxbow lakes. Following the guide’s lead also means you are more likely to see animals behaving naturally.

Conservation context: why locality matters

Tambopata’s greatest threat is gold. Small-scale alluvial gold mining has been clearing the forests of Madre de Dios since the 1980s. Amazon Conservation’s MAAP monitoring programme puts total mining deforestation in Madre de Dios at almost 136,000 hectares by mid-2025, the overwhelming majority of Peru’s total, much of it in the reserve’s buffer zone.

Enforcement has worked, at least for a time. In 2019 a government operation in the notorious La Pampa mining area cut mining deforestation there by more than 90 percent within months. But high gold prices have brought renewed pressure. In May 2026 MAAP reported that illegal mining had pushed inside the reserve itself, clearing around 500 hectares along the Malinowski River since mid-2025, despite a state of emergency and repeated police and military operations. The impact goes beyond the trees. Miners use mercury to separate gold, and studies by the Carnegie Institution in 2012 and 2013 found elevated mercury in most adults tested in Madre de Dios and in many of the fish sold in Puerto Maldonado’s markets.

Roads have brought change too. The Interoceanic Highway, built through Madre de Dios between 2005 and 2011, opened the region to settlers and farming, and the World Wildlife Fund links it to large-scale deforestation since. There are positive models as well. Since 1996 the Ese’eja and mestizo community of Infierno, on the reserve’s edge, has run an ecotourism lodge in partnership with a private company, sharing profits and management, a long-running model of community-owned ecotourism. The tour’s time in the rainforest is part of that tourism economy, which is one reason responsible visiting matters.

What health precautions should you take?

Speak to your doctor or a travel clinic well before you go. The US Centers for Disease Control and Prevention recommends yellow fever vaccination for travellers to lowland Madre de Dios, and malaria is present around Puerto Maldonado, so ask about appropriate protection. Long sleeves, trousers and insect repellent help in the forest.

What is the weather like in the Peruvian Amazon?

Usually hot and humid, with an average temperature of around 26°C. But in the dry season, particularly June and July, cold fronts known as friajes can drop temperatures sharply for a few days, so a warm layer is worth packing even here.

From Tambopata to Lake Sandoval

The second day in the Amazon is given to Lake Sandoval, one of the region’s best-known oxbow lakes, reached by boat and a forest walk before the group continues by canoe across the lake. Our article on Lake Sandoval’s oxbow ecology explores it in detail. The afternoon is free, for birdwatching, a gentle walk or rest, with the option of an evening night walk through the forest.

The Amazon days set up a revealing comparison later in the tour. Near the end of the journey, at Iguazú Falls on the Argentina–Brazil border, the group walks through subtropical Atlantic Forest, a quite different rainforest with its own species and history. Our overview of the South America cultural tour route shows how the Amazon fits the wider journey. On the South American Small Group History and Culture Tour, naturalist guides, a Program Leader and a small group of up to 16 travellers make the rainforest days both relaxed and informative.