A Study of Sea Urchin Populations Along the Rocky Coast of Ghana With a Note on Its Fishery

Abstract

ABSTRACT The research seeks to fundamentally outline the occurrence and diversity of sea urchin species along the coastline of Ghana. This work evaluates the growth parameters and some aspect of the sea urchin fishery in Ghana. Samples of sea urchins were taken from November 2020 to April 2021 at ten locations along the coast of Ghana; Tema, Nungua, La, Teshie, Nyanyano, Mumford, Cape Coast, Iture, Dixcove, and Axim. Arbacia lixula, Eucidaris tribuloides and Echinometra lucunter and an unidentified species were found during the sampling period. Arbacia lixula population dominated in the samples collected along the entire coastline of Ghana. Nyanyano had all sea urchin species in its waters. The size ranges of each species were Arbacia lixula (5.8 mm to 85.8 mm), Eucidaris tribuloides (24.7 mm to 47.7 mm), Echinometra lucunter (47.9 mm to 58.3 mm), and Unidentified sp. (20.2 mm to 27.7 mm) respectively. The diameter-weight and height relationships of the urchin species were defined by a significant positive linear relationship. Arbacia lixula (black sea urchin) and Echinometra lucunter (sea raster) were exploited at the subsistence level with few commercial engagements by some coastal dwellers. Sea urchin were harvested by 71.7 % males and 28.3 % females across the entire coast of Ghana. The minimum and maximum prices of roasted sea urchins were between USD 1.32 and 8.22 along the coast of Ghana. The active participation of both genders could be associated with proximity to the resource, diving and the use of less energy-demanding tools such as knives and sharp handy metals required for the exploitation. The sea urchin fishery presents a viable economic potential within the coastal communities which need considerable attention by policy makers.