Impacts of climate variability and change on Lake Guidimouni (Zinder/Niger) and its provided ecosystem services

Extreme climatic events are becoming more and more severe and frequent. In Niger, Lake Guidimouni an international value eco-geographic area which is home to significant biodiversity is not spared from the effects of climate change. The objective of this study was to assess the impacts of climate variability and change on the Lake Guidimouni. In this order, tendencies and variabilities of climatic factors were examined, while the ichthyological and avian faunas were studied. To complete these data, field observations were organized and surveys were conducted among local populations and municipal technical services. It appears from the results that, floods and invasive plants such as Typha australis, Eichornia crassipes are among the most common occurrences of climate variability and change effects according to 62% of respondents. According to 38% of respondents, there was an increase in the surface area of the lake Guidimouni, which has a strong impact on the socio-economic activities of populations, particularly fishing and transport throuth the lake. These events lead to a decrease in the abundance of some species of fish such as Bagrus bajad and Heterotis niloticus and birds (e.g. Burhinus senegalensus). In terms of fish and aquatic birds’ diversity, 7 species of fish divided into 4 orders, 6 families and 7 genera have been identified with a decrease of 320 tons in the fish stock between 2021 and 2022, while 34 bird’s species belonging to 10 orders, 16 families and 24 genera were recorded. These findings could be a database and a milestone for future studies.