Functional diversity of the fish fauna in the Nyong estuary (Atlantic Coast, Cameroon), and its correlation with environmental variables

Paul Alain Nana; Nectaire Lié Nyamsi Tchatcho; Anselme Crépin Mama; Fils Mamert Onana; Delf Kamogne Nono; Hassan Bassirou; Arnold Roger Bitja Nyom

doi:10.1016/j.heliyon.2023.e15649

Functional diversity of the fish fauna in the Nyong estuary (Atlantic Coast, Cameroon), and its correlation with environmental variables

Heliyon. 2023 Apr 21;9(5):e15649. doi: 10.1016/j.heliyon.2023.e15649. eCollection 2023 May.

Authors

Paul Alain Nana¹, Nectaire Lié Nyamsi Tchatcho², Anselme Crépin Mama¹, Fils Mamert Onana², Delf Kamogne Nono², Hassan Bassirou³, Arnold Roger Bitja Nyom^{3

4}

Affiliations

¹ Department of Oceanography, Institute of Fisheries and Aquatic Sciences, University of Douala, P.O. Box 7236, Douala, Cameroon.
² Department of Aquatic Ecosystems Management, Institute of Fisheries and Aquatic Sciences, University of Douala, P.O. Box 7236, Douala, Cameroon.
³ Department of Biological Sciences, Faculty of Science, University of Ngaoundéré, P.O. Box 454, Ngaoundéré, Cameroon.
⁴ Department of Fisheries Management, Institute of Fisheries and Aquatic Sciences, University of Douala, P.O. Box 7236, Douala, Cameroon.

Abstract

Archaic fishing, anthropogenic pollution linked to demographic and economic growth stand to be a real threat to the richness and abundance of the aquatic fauna of estuaries in Sub-Saharan Africa. The knowledge of the Nyong estuary ichthyofauna's ecology in Cameroon is particularly essential to establish a management plan and sustainable management of this important ecosystem. The Nyong estuary ichthyofauna was composed of 13 families, 20 genera and 22 species, from February to June 2020. Eleven species had a marine affinity while11 others were from the freshwater dirivation. Mormyridae (14%), Cichlidae (14%) and Clupeidae (14%) were the most represented families. Also, Chrysichthys nyongensis was the most abundant species with a frequency of 30.26%. Despite the low diversity in the study area, the specific diversity index showed that Dikobe was the most diverse station (H' = 2.98 and J = 0.46), contrary to Donenda's station (H' = 2.30 and J = 0.22). In general, significant correlations were noted between physico-chemical parameters and the total abundances of the different fish species (P < 0.05). Thus, in Behondo, characterized by polyhaline waters, Gnathonemus petersii in contrary Pellonula vorax was positively and significantly correlated with salinity, electrical conductivity and total dissolved solids. This study clearly illustrates that the distribution of ichthyofauna in the Nyong estuary mainly depends on the environmental variables. The data obtained would therefore allow the implementation of a sustainable fisheries development and management plan in the localities concerned by this study, and sensitize fishermen on the need to respect the fishing code.

Keywords: Diversity; Environmental variables; Ichthyofauna; Nyong estuary; Sustainable fishing.