Abstract:
This study aims at stimulating the scientific community towards a better understanding of
fish community ecology in relation to physico-chemical determinants in unmanaged
coastal wetlands relevant for informed decision-making on ecosystem functioning and
management in the tropical context. We investigated the diversity, size distribution and
food habits of the fish community and the abiotic environmental conditions of the Kakum
Estuary wetland in Ghana (5o6'N; 1 O 18 'W) from July 2009 to February 2010. Eighteen
species belonging to 18 genera and 12 families of marine, brackishwater and freshwater
fishes were sampled. The poecilid Aplocheilichthys spilauchen (43.31%), the cichlid
Sarotherodon melanotheron (18.12%) and the freshwater shrimp Macrobrachium
macrobrachion (12.37%) were dominant. Fish communities in pools in the wetland were
quite close in diversity (H' ranged from 2.2 to 2.7) and highly similar (Cs > 0.6) possibly as
a result of the prevailing similar environmental conditions. Smaller individuals of the
cichlids Tilapia zillii, Hemichromis fasciatus and S. melanotheron measuring 2.0-3.9 cm
TL, and marine species such as Elops lacerta and Liza falcipinnis measuring 6.0-7.9 cm
TL constituted between 60% and 80% of the populations, suggesting the wetland as
nursery and feeding grounds for the fishes. Examination of stomach contents showed that
the communities included detritivorous, planktivorous, insectivorous, omnivorous and
piscivorous species. It is strongly recommended to restrict fishing in the wetland during
the wet season to avoid exploitation of juvenile fishes which use the wetland as nursery
and feeding grounds during that period
