Spatio-temporal structure of fish communities Mochokidae (Ostariophysi, Siluriformes) in the Malebo Pool, Congo River (Democratic Republic of the Congo)

Abstract

At the level of Malebo Pool of the River Congo, ecological studies of Mochokidae fish communities are non-existent. This study was carried out monthly from July 2009 to October 2010, and bimonthly from March 2011 to August 2013 through experimental fishing in seven lotic and lentic stations to specify the spatio-temporal structure of these relatively abundant fish. Multivariate analysis (Canonical Redundancy Analysis) of Mochokidae stands and their habitats show segregation of species between lotic and lentic areas. The lotic habitats (Nganda Mabanga and Ile Mimosa) are colonised by species such as Chiloglanis congicus, Euchilichthys guentheri, Synodontis brichardi, Synodontis longirostris and Synodontis ornatipinnis that are located in rocky substrates with high current speed. Lentic habitats (Ngamanzo-Japon-Mipongo-Molondo-Kingabwa complex) are colonised by other species such as Synodontis acanthomias, S. decorus, S. alberti, S. notatus, S. congicus, S. caudalis, S. soloni, S. pleurops, S. nummifer and S. contractus that live in muddy and sandy substrates with submerged vegetation and weak current. The study aims to contribute towards better management and conservation of the aquatic ecosystem, specifically the habitat of the Mochokidae species, in light of the negative impacts of human developments in the Democratic Republic of the Congo.

Keywords: diversity, ecological niche, Euchilichthys, over-exploitation, Synodontis