Population of Mormyridae on the Niger River in Niamey Area: Diversity, Structure and Exploitation

In recent years, the study of Mormyridae fish in the Niger River has provided significant insights into the biodiversity and ecological health of this key habitat. Despite the extensive distribution of Mormyridae across sub-Saharan Africa, detailed studies on their population dynamics and environmental interactions remain limited. To address this gap, we conducted a comprehensive field study focusing on the diversity, structure, and exploitation of Mormyridae in the Niamey area of the Niger River. This investigation employed a multi-faceted approach, including bibliographical research, field sampling, and environmental variable measurement. Data collection was carried out at three key stations: Tondibia, Barraga Yanatalla, and Gamkalley. The study identified 15 species of Mormyridae, surpassing the 14 species recorded in previous studies. Notable species included Mormyrus rume, Marcusenius cyprinoides, and Campylomormyrus tamandua, which were found to be numerically dominant. Our findings reveal significant spatial and temporal variations in Mormyridae populations, influenced by factors such as riverine nutrient inputs and habitat conditions. The study underscores the importance of Mormyridae as bio-indicators, reflecting the health and changes in the river ecosystem. These insights contribute to a deeper understanding of the ecological dynamics in the Niger River and highlight the need for ongoing monitoring and conservation efforts to protect this vital aquatic resource.