TOWARDS SUSTAINABLE MANAGEMENT OF THE SARDINELLA FISHERY IN GHANA

Abstract

Many local fishermen in Ghana depend on the sardinella fishery for their livelihoods. Flat sardinella (Sardinella maderensis) and round sardinella (Sardinella aurita) are the two main fish species that are exploited in the fishery. Landings of the sardinella stocks, however, have been declining for over a decade now as a result of overfishing engendered by overcapacity, open access fishery and weak governance. The focus of this work was to chart the path towards a sustainable management of the fishery in Ghana by identifying the key extractive components of the fishery, ascertaining the interactions among them and the fish stocks and using the life history of the fish to simulate their population dynamics under different scenarios of seasonal closures in conjunction with gear restrictions so as to arrive at the optimal management strategy. Manuscript I: The goal of this study was to describe the basic fisher and catch characteristics as a first step in understanding the fishery and setting the basis for management decisions. We sampled 8 sites along the coast of Ghana from 2017-2018 and collected data on over 14,000 individuals of sardinellas from 332 unique fishing trips. We found three broad categories of fishing gears: beach seines, purse seines and gill nets. Three types of purse seines were identified and distinguished based on mesh sizes: poli ≤ 3.0 cm; watsa > 3.0 cm; and poli-watsa had a combination of mesh sizes. Differentiation of gill nets was based on either monofilament (called “set net”) or cotton (called “ali”). Poli-watsa constituted the most dominant gear in the fishery. Two species of sardinella were captured, the round (Sardinella aurita) and the flat (Sardinella maderensis) sardinella. Ninety-six percent of the vessels were motorized. The landings were predominantly juveniles. Considering the dominance of juveniles in the landings of the sardinella fishery in Ghana, management that reduces effort using specific gears or eliminates fishing during certain times of the year could be effective. Manuscript II: Sardinella stocks made up of flat sardinella (Sardinella maderensis) and round sardinella (Sardinella aurita) form the mainstay of the artisanal fisheries of Ghana. The landings of these stocks, however, have been dominated by small, immature fish in recent years. Yet, no comprehensive assessment has been conducted to identify the fishing gears that unsustainably harvest juvenile fish and what factors drive their distribution. In this study, we examined the distribution of sardinella species in the Ghanaian fishery and used length at