Hydrologic Connectivity Affects Fish Assemblage Structure, Diversity, and Ecological Traits in the Unregulated Gambia River, West Africa

Altered hydrologic connectivity due to damming significantly impacts fish assemblage structure, diversity, and ecological traits in the Gambia River, West Africa. The study found that species richness increases with isolation from the main river during the dry season, while the abundance of elongate-bodied fishes rises with isolation in the wet season—patterns that disappear under altered flow regimes. Researchers compared 49 fish species across riverine and floodplain habitats in Niokolo-Koba National Park, revealing seasonal shifts in habitat use and trait distribution tied to natural lateral connectivity. These findings highlight the vulnerability of taxonomic and functional diversity to planned dam construction, emphasizing the ecological importance of unregulated flow dynamics.

White, S. M., Ondračková, M., & Reichard, M. (2011). Hydrologic Connectivity Affects Fish Assemblage Structure, Diversity, and Ecological Traits in the Unregulated Gambia River, West Africa. Biotropica, 44(4), 521–530. Portico. https://doi.org/10.1111/j.1744-7429.2011.00840.x