Aspects of the Feeding Ecology of Some Selected Fish Species Assemblages of an Estuarine Mangrove Ecosystem in Ghana

Abstract

Food and feeding habits of commercial fish species from Kakum River Estuary and Benya Lagoon were studied purposely to assess the range of food items available to the species in the brackish ecosystems. The quality of naturally available food resources within a brackish ecosystem influences the feeding habits of fish. Fish samples for the study were obtained with a cast net and were examined employing the frequency of occurrence method. The diet of the species from both the estuary and the lagoon were similar, with minor dissimilarities in the proportions of the recorded food items. While diatom, zooplankton, sand particles, detritus, and polychaetes occurred to be the most essential food items for grey mullets (Mugilidae) from the estuary, blue-green algae, polychaetes, and detritus was the preferred food for the species in the lagoon. The core feeding cycle of grey mullets in the Kakum River Estuary occurred during the diurnal period between the hours of 14:00 GMT and 18:00 GMT for all sampling dates. There was not much or no feeding during the nocturnal period except Mugil curema which feeding activity peaked at 2:00 GMT sampling. The peak feeding activity for Liza dumerilli, Liza falcipinnis, Mugil bananensis, and Mugil curema occurred at 14:00 GMT and 18:00 GMT while the peak feeding activity for Mugil cephalus occurred at 18:00 GMT during the day for all the sampling dates. Liza dumerilli, Mugil cephalus, and Liza falcipinnis occurred to be species with high feeding intensity at low tides.