“We’ve seen fish in the cocoa plantation”: the impact of climate change on biodiversity in the Republic of the Congo
The Congo Basin is the second-largest contiguous tropical rainforest in the world after the Amazon; it plays a vital role in mitigating global climate change and is home to exceptional biodiversity, including endangered megafauna species such as the African forest elephant (Loxodonta cyclotis), the western lowland gorilla (Gorilla gorilla gorilla) and the bonobo (Pan paniscus).
Despite its crucial role within the Earth’s system, the Congo Basin nevertheless suffers from a significant lack of research, exacerbated by the absence of long-term monitoring.
New research conducted by Sapienza, coordinated by Carlo Rondinini of the ‘Charles Darwin’ Department of Biology and Biotechnology and with PhD student Milena Marie Beekmann as lead author, offers new insights into the as yet largely undocumented impacts of climate change on biodiversity and on forest-dependent communities in the Congo Basin. The study drew on both local ecological knowledge and meteorological data.
Using a mixed-methods approach, comprising focus group discussions, semi-structured interviews and a quantitative survey, the researchers documented local climate change and the biophysical effects observed by local communities in the Lake Télé Community Reserve, an important protected area in the north of the Republic of the Congo, which is home to the world’s highest estimated density of Gorilla gorilla gorilla. The study also examined the adaptation strategies adopted by local communities in the Lake Télé Community Reserve, as well as their potential impacts on biodiversity.
The study is based on six months of fieldwork in the Lake Télé Community Reserve, which contains a mosaic of ecosystems – forests subject to seasonal flooding, dryland, marshes and savannahs – under difficult logistical conditions, given the remoteness of the site and the lack of basic infrastructure such as drinking water, electricity or telephone access. In particular, the fieldwork took place during the floods of 2023, when water levels in villages, agricultural fields and forested areas were described as the highest ever recorded in living memory.
Among the key findings of this study were the numerous climate changes documented by local communities, such as rising temperatures, changes in rainfall patterns and alterations to the flood regime – all phenomena that are broadly consistent with the available meteorological data. Significant changes in the Reserve’s flood patterns are constantly being reported, with an increase in the frequency of floods of unprecedented magnitude and duration.
Furthermore, the impacts of climate change on biodiversity include changes to the migration patterns of numerous mammals, birds and fish; a decline in the production of wild berries; a reduction in the availability of edible wild caterpillars; increased tree mortality attributable to changes in flooding patterns; and significant effects on agriculture, fishing and hunting.
Respondents reported over 30 strategies for adapting to the impacts of climate change, both on and off farm; some of these have negative effects on biodiversity, whilst for the majority the effects are unclear.
The impacts of climate change observed by the Reserve’s inhabitants may reflect broader regional patterns found in other floodplain ecosystems, highlighting the urgent need to assess changes in seasonal flooding and rainfall in swamp forests, seasonally flooded sites and other types of habitat.
If the impacts – including the decline in fruit availability – reported by the interviewees were widespread throughout the Reserve and the wider Congo Basin, this could have far-reaching ecological consequences, particularly for Gorilla gorilla gorilla, a key frugivorous species.
This study demonstrates that local ecological knowledge is an essential scientific tool in a region with high biodiversity and limited data availability, enabling a rapid, taxon-wide assessment of ecological changes. Local communities have adapted to seasonal flooding and hydrological changes in the Likouala-aux-Herbes River. However, new changes to hydrological systems caused by climate change are now having an impact on livelihoods and forest ecosystems.
References: Beekmann, M., C. Rondinini, C.-L. Moungouya-Moukassa, A. Loumouamou, A. Lauta, A. Cuni-Sanchez, and S. Gallois. 2026. “We saw fish in the cocoa farm”: local observations of the impacts of climate change on biodiversity and livelihoods in the Lac Télé Community Reserve, Congo Basin. Ecology & Society (2026)
DOI: 10.5751/ES-16964-310231
Further Information
Carlo Rondinini – Department of Biology and Biotechnology “Charles Darwin”
Milena Marie Beekmann - Department of Biology and Biotechnology “Charles Darwin”
milenamarie.beekmann@uniroma1.
Credits immagini: Milena Beekmann
