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- Understorey-nesting bird community responses to land use in the Korup National Park, an Afrotropical rainforest in South-Western CameroonPublication . TONLEU, JEAN; Tsafack, Noelline; Bobo, Kadiri S.; Lhoumeau, Sébastien; Lontchi, Wilfried G.T.; Tanebang, Cyrille L.T.; Mbida, MpoameTropical forest biodiversity is under immense pressure due to a combination of global and local factors, including climate change and intensive land use. Birds play an important role in tropical forest ecosystems, contributing significantly to various ecosystem services. This study examined the impact of deforestation on the richness and abundance of understorey-nesting bird communities along a land-use intensification gradient in the peripheral zone of Korup National Park, Southwest Cameroon. We selected 30 sampling plots, each covering 4 ha, across five habitat types: near-primary forest, secondary forest, disturbed forest, cocoa/coffee plantations, and annual food crop fields. A total of 236 understorey bird nests were identified, representing 16 species. Our findings revealed that land use intensity significantly influenced bird species richness and abundance. Primary and secondary forests provided 75% of the nesting species and 71% of the nests. However, 19% of the species either appeared or increased in cocoa/coffee plantations and annual crop fields. Among the feeding groups, frugivores were the most sensitive group to deforestation. This study corroborates the adverse effects of forest destruction on birds communities and highlights the urgent need to address the rapid and extensive forest conversion occurring within Korup National Park. Allowing secondary forests to regenerate and preserving large patches of primary forest are essential strategies to help understorey-nesting bird communities mitigate the impacts of global changes.
- Conservation Value of Sudanese Savannah Land Use Systems for Birds in the Lagdo Area, North CameroonPublication . TONLEU, JEAN; Kougoum, Ghislain; Wandja, Vanessa; Tsafack, Noelline; Lhoumeau, Sébastien Georges André; Kamga, Solange; Riegert, JanABSTRACT: Aggregate biodiversity metrics frequently mask profound structural shifts in human-modified savannahs, creating a persistent paradox where apparent ecological stability conceals severe community reorganization and functional degradation. To resolve this tension in the Sudanese savannah of North Cameroon, systematic sampling of 4,166 individuals across 68 species quantified avian responses to landscape conversion into Mixed Rural Habitats, Rice Paddies, and Annual Crop Fields. Although aggregate species richness and abundance remained invariant across these land-use types, pairwise comparisons confirmed that each habitat supports a distinct avian signature, driving systematic community turnover rather than taxonomic attrition. Community identity partitioned decisively by land-use, with Annual Crop Fields supporting 39.7% of unique species, Rice Paddies at 26.5%, and Mixed Rural Habitats at 7.4%. Furthermore, 13.23% of recorded species were exclusively restricted to these agricultural systems, establishing land-use type as a statistically significant predictor of community assembly and confirming that each habitat contributes a unique structural component to the regional species pool. Functional organization mirrored this targeted reconfiguration; while most feeding guilds exhibited resilience to modification, Aquatic predator and Omnivore abundances proved highly sensitive to land-use variation, identifying these specific guilds as critical functional sentinels of anthropogenic disturbance. Ultimately, these dynamics fundamentally reframe the conservation value of agricultural savannahs, shifting the primary metric of success from gross species counts to the preservation of compositional turnover and functional integrity. The persistence of these diverse assemblages remains strictly contingent upon the structural complexity of the land-use mosaic rather than the mere localized absence of human activity. Consequently, effective conservation in the Sudano-Sahelian biome necessitates management frameworks that transcend simple habitat preservation to actively integrate native vegetation within productive agricultural systems, ensuring that unchecked agricultural expansion does not precipitate silent functional homogenization across the rapidly transforming African tropics.