Occurrence, abundance, food and feeding habits of fish species in Cross River Estuary (Ibaka Beach), Nigeria

Abstract

Occurrence, abundance, food and feeding habits of fish species in Cross River Estuary was studied for five months. A total of 386 fish samples comprising of 23 families, 29 genera and 40 species were collected. The most abundant species were Arius gigas, Ethmalosa fimbriata, Ilisha africana, Cynoglossus senegalensis, Liza falcipinnis, Galeoides decadactylus, Pseudotolithus senegalensis and Trichiuris lepturus, which occurred throughout the sampling period. The least abundant species were Carcharhinus falciformis, Mugil cephalus, Lutjanus goreensis and Sphyraena sphyraena. The most abundant family was Sciaenidae (15.30%), followed by Clupeidae and Ariidae (14.80% and 11.16% respectively). Out of the 386 specimens examined, 77(19.95%) had empty stomach, 65(16.83%) had full stomach while 80(20.73%), 89(23.06%), and 75(19.43%) had ¾, ½ and ¼ respectively. Animal preys dominated the stomach contents of the dominant predatory groups. Other items found in the stomachs of some species were partially digested plant parts and mud. Stomach content analysis revealed that fishes of Cross River estuary were mostly euryphagous with few detritus and filter feeders. Diversity indices revealed significant differences among species and the mean condition factor was 2.27.

Keywords: Fish Species, Occurrence, Food, Feeding Habits, Cross River Estuary