Fish species composition, diversity and abundance of the lower New-Calabar River, Rivers State

Abstract

A thirteen-week investigation to determine the fish species composition, diversity and abundance of the Lower New Calabar River, in Rivers State, aimed at providing information on the fish stock and their status for documentation, knowledge improvement, and development of conservation and management strategies was undertaken. Five stations along the river were sampled and fish randomly collected from fisher-folks twice weekly. Fish composition, diversity and abundance were determined using standard methods. Results revealed a total catch of54,404 fishes, composing of 36 species from 29 families; with diversity highest in the family Cichlidae (11.1%) and least in Cyprinodontidae (2.8%), and relative abundance highest for Sardinella maderensis (32.29%) and least for Polycentropis abbreviate (001.84%)and Aplocheili chthysspilauchen (001.84%). Thus, the river has a high species composition but diversity and abundance vary probably due to differences in physico-chemical parameters and fishing pressure. Also, some certain species were threatened (eg. Lutjanus spp, Aplocheili chthysspilauchen). This may also be connected with fishing pressure and environmental factors. Therefore, a detailed and longer research be undertaken on this River to elucidate the fish stock and their status to develop their knowledge, and appropriate conservation and management strategies for the fishes and fisheries.

Key Words: Fish stock, relative abundance, species diversity, New Calabar River, Nigeria