Geographic Atlas and Mapped Landscapes of Área Protegida Municipal Rhukanrhuka in Bolivia

The origins of Rhukanrhuka as a formally recognized protected area date back to a 2008 proposal by the municipal government of Reyes, which approved the creation of the Área Protegida Municipal Los Santos Reyes. That initiative aimed to promote tourism and conserve the natural resources of the municipality, but it failed to develop a stable legal foundation, did not carry out adequate consultation with local communities, and lacked management instruments.

In 2018, the proposal was reopened with a broader, more participatory approach. Local actors from different sectors of Reyes came together to revise the framework, and on 25 June 2019, the Área Protegida Municipal Rhukanrhuka was formally created through Municipal Law N°197. The new designation was inspired by the Maropa indigenous name for the lucachi monkeys, two species of titi monkeys endemic to Bolivia that live within the area, an intentional alignment between the park's identity and the indigenous cultural presence in its territory.

The creation of Rhukanrhuka marked a shift from a top-down tourism-oriented proposal to a more inclusive municipal conservation strategy. It also positioned Reyes alongside other Bolivian municipalities, such as Ixiamas and Santa Rosa de Yacuma, that have used municipal protected areas as instruments of decentralized biodiversity conservation in the northern Amazon.

Rhukanrhuka occupies a broad transitional zone in the northern Bolivian Amazon, where the easternmost foothills of the Andes gradually disappear into the vast Llanos de Moxos floodplain. The terrain is relatively flat on a regional scale, reflecting the lowland character of the Beni department, but it is far from monotonous: small variations in elevation, river systems, geological substrates, and hydrology produce striking ecological contrast.

Hydrography shapes the landscape more than topography does. The protected area lies in the mid-to-upper portion of the Madeira river basin, between the sub-basins of the Beni and Mamoré rivers. White-water rivers originating from Andean erosion, including the Beni along the western boundary, the Biata crossing from southwest to northeast, and the Hondo in the south, carry heavy sediment loads that give their waters their characteristic turbid, light "white" color. These rivers cut through the forests and create extensive riverine corridors.

Meanwhile, the eastern part of Rhukanrhuka features a chain of deep tectonic lakes formed by the collapse of underlying bedrock along the Bala-Rogagua line. The largest of these is Lago Rogagua, followed by lakes such as San Lorenzo and Yusala. Their waters, like those of the surrounding rivers, are strongly seasonal, fluctuating with rainfall and the flooding cycles of the southern Amazon. Together, the erosional rivers of the west and the tectonic lakes of the east define a landscape that merges fluvial, lacustrine, and savanna environments into a single dynamic mosaic.

Vegetation in Rhukanrhuka expresses the same transition that defines its physical setting. Roughly 19 vegetation units have been identified in the protected area, with forests of various types covering around 60 percent of the surface and savannas covering another 30 percent. Vegetation tied directly to rivers, lakes, and wetlands accounts for about 5 percent, while human-modified areas remain under half a percent, illustrating how the landscape is still largely in natural condition.

The most extensive forest formations are the complex of gallery and riparian vegetation associated with the white-water rivers of the Beni system, together with non-alcaline savannas of Beni that transition toward cerrado ecosystems. Forests are typically concentrated along the Beni and Río Negro corridors, while savannas dominate the central and eastern sectors. The combination of these formations creates a high-value habitat mosaic that supports both forest-dependent species and those adapted to open landscapes.

Floristic data on Rhukanrhuka are still developing, but historical riverine forest surveys show high species richness with a strong presence of legumes and palms. Local communities also use and recognize species such as motacú (a native palm), cacao, guayaba, and achachairú, while historically valuable timber species like mara (Swietenia macrophylla), cedro (Cedrela odorata), and roble (Amburana cearensis) have shaped long-standing patterns of forest use and pressure.

Rhukanrhuka's fauna reflects the convergence of ecosystems found across the Andes-to-Moxos transition. Roughly half of the mammal species documented within the area exhibit some degree of conservation threat, mainly driven by hunting and habitat loss, and the combination of forests and savannas supports both rare large mammals and a wide variety of smaller species.

Among the most emblematic mammals is the Bolivian river dolphin, the bufeo, a freshwater cetacean endemic to Bolivia's rivers. Other large mammals recorded in the area include the jaguar, puma, lowland tapir, and multiple deer species, including the marsh deer, the pampas deer or gama, the red brocket or huaso, and the gray brocket or urina. The protected area is also a key stronghold for Bolivia's two endemic titi monkeys, the reddish lucachi (Callicebus olallae) and the grayish lucachi (Callicebus modestus), both classified as endangered and central to the area's identity.

The avifauna is one of Rhukanrhuka's most distinctive features, with the area recognized as an Important Bird Area due to the presence of the wattled curassow, locally known as pava mamaco, whose only known Bolivian population lives in the upper basin of the Río Negro, within the protected area. The curassow is critically endangered both nationally and globally, mainly because of historical hunting and habitat fragmentation.

Aquatic and reptilian wildlife is also exceptional. Threatened reptiles include the black caiman, the spectacled caiman (locally called lagarto), the yellow-spotted river turtle (peta de río), and the Bolivian anaconda, a recently described species endemic to northern Bolivia. The fish fauna is still only partially documented, with estimates of more than 220 species, including important food fishes such as surubí catfish, piranhas, and the introduced paiche, with knowledge suggesting broader species concentrations in riparian forests and forest-savanna transition zones.

Rhukanrhuka plays an important role in Bolivian conservation because of its size, its ecological position at the Andean-Moxos transition, and the number of threatened species it shelters. Covering around 8,500 square kilometers, it functions as a critical buffer and complement to neighboring protected areas, particularly the adjacent Bajo Madidi municipal conservation area and Madidi National Park, one of the most biodiverse protected areas on Earth, located only about 11 kilometers away. Together, they extend a continuous conservation corridor from the Andes into the western Amazon.

The protected area's conservation value is enhanced by its formal recognition as an Important Bird Area for the conservation of the wattled curassow, one of the most threatened large birds in South America. It is also a refuge for the two endemic Bolivian titi monkeys, whose populations are otherwise highly restricted. Threatened reptiles such as the Bolivian anaconda, black caiman, and yellow-spotted river turtle further highlight its importance as habitat for aquatic and wetland species.

Consistent with Bolivia's model of municipal-level protected areas, Rhukanrhuka is administered by the Government of Reyes under the framework of a Municipal Natural Area of Integrated Management. This governance model allows for the combination of strict conservation, sustainable use, and recognition of indigenous land use, including the presence of the Maropa people. While the area faces ongoing pressures from hunting, timber extraction, habitat fragmentation, and the introduction of species such as paiche, its formal establishment in 2019 represents an important step toward long-term protection of one of Bolivia's most ecologically rich northern Amazonian regions.

Rhukanrhuka is named using a word from the Maropa language, one of the Tacana-language family spoken by indigenous peoples of the northern Bolivian Amazon. The name directly refers to the lucachi monkeys, the two species of titi monkeys endemic to Bolivia that inhabit the area, a deliberate symbolic link between the protected area's identity and the indigenous communities that live within it.

The Maropa people are a Tacana-language indigenous group whose presence inside Rhukanrhuka adds an important human and cultural dimension to the conservation landscape. Their settlement in the area reinforces the protected area's character as a living territory with both biodiversity and ancestral cultural values.

Within Rhukanrhuka lies Uaua-Uno, the only archaeological site in the broader Reyes region that has been systematically investigated. Rescued (salvaged) in 2004, Uaua-Uno provides evidence of long-standing human occupation and gives the protected area an archaeological dimension that complements its ecological significance, though broader pre-Hispanic and historical context for the region is still being researched.

Rhukanrhuka combines three characteristics rarely found together at this scale: a continuous gradient from the Andes to the Moxos plains, the presence of multiple species of strong conservation concern, and an active indigenous Tacana-language community whose naming language is embedded in the protected area's identity.

Its white-water rivers, tectonic lakes, gallery forests, and savanna mosaics provide habitats for species as varied as the Bolivian river dolphin, jaguar, lowland tapir, endangered titi monkeys, the critically endangered wattled curassow, and the Bolivian anaconda. Together with the proximité of Madidi National Park and the Bajo Madidi municipal conservation area, these features make Rhukanrhuka a vital, living link in one of the most ecologically significant corridors in the Amazon.

Rhukanrhuka's landscapes and water levels are strongly shaped by the seasonal pulse of the southern Amazon. The rainy season feeds the white-water rivers of the Beni system and raises the water levels of Lago Rogagua, San Lorenzo, and Yusala, expanding floodplains, increasing riverine habitat connectivity, and intensifying aquatic wildlife activity. The dry season contracts these water bodies and concentrates fauna around the remaining river channels, lakes, and forest-savanna edges, often making terrestrial wildlife easier to observe.

For visitors interested in aquatic ecosystems and flooded forests, the wetter months generally offer more dramatic river and lake scenery, while the drier months can provide clearer conditions for terrestrial wildlife viewing along forest edges and savanna patches. In both seasons, conditions reflect the area's strong ecological seasonality rather than a fixed tourism calendar, and timing choices depend primarily on whether the focus is rivers and lakes, terrestrial wildlife, or cultural exchange with local communities.