Lake Télé-Lake Tumba swamps
Lake Télé-Lake Tumba is a significant freshwater ecosystem situated at the border between the Republic of Congo and the Democratic Republic of Congo, with 65% of its area in the DRC. Spanning approximately 48,649 square miles (126,000 square kilometers), it is recognized for its rich biodiversity, being the only region in Africa that houses three great ape species: the bonobo, central chimpanzee, and western lowland gorilla. This unique biome comprises a variety of habitats, including extensive swamp forests and mixed terra firma forests, supporting an impressive array of wildlife and plant species, with about 10% of its vascular plants being endemic.
The area faces multiple environmental threats, mainly due to industrial logging, bushmeat hunting, and a lack of effective law enforcement, which jeopardize both its biodiversity and the livelihoods of local communities. The human population in this region is culturally diverse, consisting of various Bantu tribes and indigenous groups, with livelihoods based on fishing, agriculture, and forest product exploitation. As research into this area has increased in recent years, it has revealed new species and highlighted the ecological significance of the Lake Télé-Lake Tumba region, emphasizing the urgent need for conservation efforts to protect its unique biodiversity amid mounting human pressures.
Lake Télé-Lake Tumba swamps
- Category: Inland Aquatic Biomes.
- Geographic Location: Africa.
- Summary: This large freshwater ecosystem is the only landscape in Africa with three great-ape species. The biome is threatened by industrial logging, rampant commercial bushmeat hunting, and lack of law-enforcement activities.
Lake Télé-Lake Tumba is an inland equatorial ecosystem located at the border of the Republic of Congo (ROC) and the Democratic Republic of Congo (DRC), 65 percent being in the DRC. At 48,649 square miles (126,000 square kilometers), it occupies most of the Cuvette Centrale, or Central Basin, and lies in the Guineo-Congolian vegetation zone, a complex and diverse botanical region. The Lake Télé-Lake Tumba biome supports some 1,500 to 2,000 vascular plant species, of which 10 percent are endemic (found nowhere else); the region is a regional center of endemism. It also hosts abundant fauna species—including three great-ape species, making it unique in Africa.
Flora
Some 60–65 percent of the landscape north of 1 degree, 30 minutes south is a vast zone of seasonally inundated and permanent swamp forest. By contrast, in the zone south of that latitude, comprising some 35–40 percent of the Lake Télé-Lake Tumba biome, are found mixed terra firma forest types, including mature and secondary forests along valleys and on small hills. These ombrophile (shade-tolerant) and semi-deciduous forests occur in areas between the major river systems here.
Both types are composed of stands of leguminous trees, characterized by hardwood timber species such as Staudtia stipitata, Polyalthia suavaeoleus, Scorodophloeus zenkeri, Anonidium mannii, and Parinari glaberrimum, which serve as important fruit and seed sources for great apes and other wildlife.
Between the Ubangi and Ngiri Rivers are spots of forest dominated by the evergreen Limbali tree (Gilbertiodendron dewevrei), providing an important food base for an array of mammals including humans. Areas of seasonally inundated forest and numerous large clearings occur along the major riverbanks in the north, east, and west of the biome. The southern reaches of the landscape are a forest-savanna ecosystem on the Bateke Plateau, a relatively drier area. Evolutionarily savanna-adapted species share their habitats with forest-adapted species, which explains why this ecosystem is one of the most diverse in central Africa.
Biodiversity
The Lake Télé-Lake Tumba biome is the only place where three endangered species of great ape—bonobo (Pan paniscus), central chimpanzee (Pan troglodytes), and western lowland gorilla (Gorilla gorilla)—are sympatric in their wild range, though separated by the Congo and Ubangi Rivers. A relatively large population of forest elephants also resides in this biome, along with important populations of forest buffaloes, bongos, sitatunga, bushbucks, leopards, lions, seven species of duikers, and seven species of diurnal monkeys.
Freshwater biodiversity here is composed of more than 150 fish species and also includes the hippopotamus, African slender-snout crocodile, dwarf crocodile, Nile crocodile, water chevrotain, giant otter shrew, Congo clawless otter, and Hartlaub’s duck.
Much of the biodiversity of Lake Télé-Lake Tumba remains poorly described. Relationships among that biodiversity, and environmental and human conditions that influence the distribution and the abundance of that biodiversity, remain inadequately elucidated. This lack of knowledge can be attributed to the fact that Lake Télé-Lake Tumba became a focus of conservation and research only in the recent past. Fresh studies, however, have found that its forests may have remained wetter year-round over the past twenty centuries.
Various research has described the most important continuous population of bonobos in the wild, the presence of lions in savannas within the forest, species of fish new to science, and one new species of bird that was thought to occur only in east Africa. Additional studies have, for the first time, described the discovery of chimpanzees dwelling in swampy habitats. These findings, taken together, indicate that there may be more species waiting to be uncovered and understood in this fecund region.
Human Cultures
Lake Télé-Lake Tumba supports high cultural diversity. The DRC side comprises 30 Bantu tribes of common historical background, and the autochthonous Batswa and Balumbe. Human population densities vary from a mean of 3.5 people per 0.4 square mile (1 square kilometer) in the north, to a mean of eight people per 0.4 square mile (1 square kilometer) in the south. In the north, people are spread across a vast forested area, while in the south, they are distributed among permanent settlements along the rivers, including the shores of Lake Tumba and Lake Maindombe.
In the north, human livelihoods consist primarily of fishing, cultivation of cassava, and hunting in adjacent forests. The people of the south live in the large and midsize towns (Mbandaka, Inongo, and so on), which are markets for forest products. The Batswa and Balumbe are located mostly in the administrative territories of Bikoro, Inongo, and Kutu. Their livelihood is heavily dependent on exploitation of forest products.
Environmental Threats
Biodiversity is threatened by a cohort of anthropogenic factors, including industrial logging and a high level of poverty among local populations, leading to direct pressure on scant resources. The most endangered wildlife species in the Lake Télé-Lake Tumba area exhibit a natural vulnerability from low reproduction rates due to prolonged gestation and long inter-birth intervals, as observed in all three species of great ape, as well as the forest elephants.
The southern part of the DRC side of this biome is heavily logged. Despite the lack of data on the effects of logging on bonobos, the bonobos and chimpanzees resident on the DRC side are closely related, and may be highly vulnerable to stress caused by disturbance from logging activities, as was demonstrated in the case of chimpanzees in Gabon. Logging operations threaten prime habitat for bonobos in the southern zone of the biome; most of the suitable habitat for bonobos occurs within logging concessions.
Seeking economic opportunities connected to industrial logging operations, immigrants have been increasingly settling in this area over the past two decades. Increased human populations in the south have wiped out local forest-elephant populations. Human immigrants have occupied zones that were suitable for elephant seasonal migrations, leading to increased human-elephant conflict caused by competition for forest fruits and corridor land. Commercial bushmeat hunting is rampant, and is facilitated by increasing availability of weapons and ammunition, ease of access to the landscape through the river network, and the complicity of the army and local political leadership. Illegal poaching of elephants for their tusks also threatens species here.
Bibliography
Inogwabini, Bila-Isia, et al. “The Bonobos of the Lake Tumba–Lake Maindombe Hinterland: Threats and Opportunities for Population Conservation.” In Takeshi Furuichi and Jo Myers, eds., The Bonobos: Behavior, Ecology, and Conservation. Thompson. New York: Springer, 2007.
Inogwabini, Bila-Isia, et al. “Great Apes in the Lake Tumba Landscape, Democratic Republic of Congo: Newly Described Populations.” Oryx 41, no. 4 (2007).
Inogwabini, Bila-Isia et al. “Great Apes in the Lake Tumba Landscape, Democratic Republic of Congo: Newly Described Populations.” Oryx vol. 41, no. 4, 2007, 532–38, www.cambridge.org/core/journals/oryx/article/great-apes-in-the-lake-tumba-landscape-democratic-republic-of-congo-newly-described-populations/E7CB9FD2F7520C22E2363A4F423326B8. Accessed 1 Dec. 2024.
Inogwabini, Bila-Isia, et al. “Protected Areas of the Democratic Republic of Congo: A Habitat Gap Analysis to Guide the Extension of the Network.” Endangered Species Update 22, no. 2 (2005).
“Lac Télé-Lac Tumba Landscape.” U.S. Agency for International, 2017-2020.usaid.gov/sites/default/files/documents/1860/CAFEC‗Lac‗Tele-‗Lac‗Tumba‗Fact‗Sheet.pdf. Accessed 1 Dec. 2024.
Ndinga, Adrien Boika Mondzoi, Willy Lusasi Swana, Camille Nsimanda Ipey, Victor Pwema Kiamfu, and Dieudonne Musibono Eyul'anki. "Distribution in the Flooded Swamp Forest of the Lake Tumba Micro-Basin on the Mbandaka-Research Center in Ecology and Forestry of Mabali (CREF Mabali) Road Axis in Bikoro, Equateur Province (DR Congo)." Annual Research & Review in Biology, 2022, pp. 25-43. DOI: 10.9734/arrb/2022/v37i730520. Accessed 1 Dec. 2024.
Twagirashyaka, Félin and Bila–Isia Inogwabini. “Lake Télé-Lake Tumba Landscape.” In Carlos De Wasseige, et al. The Forests of the Congo Basin—State of the Forest 2008. Luxembourg: Publications Office of the European Union, 2009.