Isaac Okyere

University of Cape Coast | UCC · Department of Fisheries & Aquatic Sciences

Microplastic ingestion by marine organisms presents a challenge to both ecosystem functioning and human health. We characterized microplastic abundance, shape, size, and polymer types ingested by the West African mangrove oyster, Crassostrea tulipa (Lamarck, 1819) sampled from estuaries and lagoons from the Gambia, Sierra Leone, Ghana, Benin, and N...

Small-scale fisheries are significant sources of nutrition and livelihood globally. However, increasing anthropogenic activities in coastal areas of developing countries have threatened the sustainability of artisanal fisheries and species. Fisheries of Sardinella maderensis, towards the global stock of which Nigeria contributes 9% and which is a s...

Aspects of the reproductive biology of Atlantic chub mackerel Scomber colias are reported here based on data from random samples of artisanal fish landings from Ghana. The specimens were between 13.7 cm and 40.7 cm total length (TL), and both sexes matured at a mean length (Lm50) of approximately 25 cm TL. An overall sex ratio of 1:1 was estimated...

The governance of coastal and marine resources remains a complex socio-ecological endeavor in many African countries, but women are leading the way and demonstrating a pathway for food fish security through rights-based co-management of shellfisheries in estuarine and mangrove ecosystems in West Africa. We report comprehensively, for the first time...

Tropical fish stocks are perceived not to exhibit seasonality in growth. For this reason the standard von Berta- lanffy growth function (VBGF) has been used widely to fit the growth of tropical fish populations compared to the seasonally-oscillating VBGF (soVBGF), which is seldom used in tropical fisheries. To advocate for the use of the soVBGF in...

Aside from ornamental uses, there is growing interest in using killifishes for a multiplicity of purposes including baitfish and mosquito biocontrol. This experiment explored the spawning habits and embryonic development of the banded lampeye, Aplocheilichthys spilauchen in ex situ freshwater (0.04‰) and brackish water (5.01‰) to ascertain the capt...

Penaeid shrimps are crustaceans of high commercial value. The habitat distribution and aspects of biology of penaeid shrimps were investigated as a contribution to filling the knowledge gap on the stocks of shrimps in inshore waters of Ghana. Monthly samples of the penaeids were obtained from commercial inshore trawlers at Tema, Elmina and Sekondi...

The novel coronavirus is predicted to have dire implications on global food systems including fisheries value chains due to restrictions imposed on human movements in many countries. In Ghana, food production, both agriculture and fisheries, is exempted from restrictions as an essential service. The enforcement of COVID-19 prevention protocols, par...

Effective conservation management combines information obtained from formal scientific research with traditional knowledge derived from communities living within the ecosystem, in an integrated and comprehensive ecosystem assessment. To complement national efforts to establish Marine Protected Areas (MPAs) in critical coastal ecosystems to protect...

Aside from ornamental uses of killifishes, there is growing interest in using killies for a multiplicity of purposes including baitfish and mosquito biocontrol. This experiment explored the spawning habits and embryonic development of the banded lampeye, Aplocheilichthys spilauchen in ex situ freshwater (0.04 ‰) and brackish water (5.01 ‰) to ascer...

This report is a Draft Literature Review for Activity 1 of the USAID Women Shellfishers and Food Security Project, which is a co-creation of the University of Rhode Island and partners from West Africa – the University of Cape Coast in Ghana, the University of Ghana, TRY Oyster Women’s Association in The Gambia, and World Agroforestry. This project...

This paper reports on the fishery and some population parameters of the cassava croaker (Pseudotolithus senegalensis) at Anlo Beach near Shama (5°01’ N, 1∘37’ W) in the Western Region of Ghana. The study was conducted from July 2012 to June 2013 to contribute to information on the dynamics of demersal stocks in the country. Beach seining was the pr...

This paper reports on the fishery and some population parameters of the cassava croaker ( Pseudotolithus senegalensis ) at Anlo Beach near Shama (5° 01' N, 1°37' W) in the Western Region of Ghana. The study was conducted from July 2012 to June 2013 to contribute to information on the dynamics of demersal stocks in the country. Beach seining was the...

Increasing global seafood demand over the last couple of decades has resulted in overexploitation of certain fish species by both industrial and small-scale artisanal fishers. This phenomenon has threatened the livelihoods and food security of small-scale fishing communities especially in the West African sub-region. In Ghana, fish transshipment (l...

The novel coronavirus is predicted to have dire implications on global food systems including fisheries value chains due to restrictions imposed on human movements in many countries. In Ghana, food production, both agriculture and fisheries, is exempted from restrictions as an essential service. The enforcement of COVID-19 prevention protocols, par...

The Guinea shrimp, Holthuispenaeopsis (= Parapenaeopsis) atlantica (Balss, 1914) is exploited by traditional and commercial fisheries in the Gulf of Guinea, West Africa. We assessed growth, mortality, ovarian maturity, and exploitation of the population of the species in inshore waters of Ghana as a contribution of filling the knowledge gap on the...

Ghana’s fisheries sector is collapsing despite the existence of numerous governance structures, regulatory and policy frameworks that have been put in place for development of the sector. To understand the complexity from the governance perspective, the Far Ban Bo Project instituted this state of fisheries governance assessment to identify challeng...

This policy brief has been compiled as outcome of an assessment of the State of Fisheries Governance in Ghana conducted for the Far Ban Bo project from December 2019 to February 2020, with an overall objective of contributing to reforms and improvements within the fisheries sector. The fisheries sector of Ghana employs about 3 million people direct...

Building Capacity for Phage Application in management of livestock production diseases: an African Union Project on Tilapia disease management on aquaculture farms in Ghana and Uganda.

The Pra River Estuary, which is the second largest estuary in Ghana, has been under severe threat of siltation from illegal alluvial gold mining activities over a decade. To advocate the need for its conservation, the study assessed the ecological health status of the estuary and its connecting wetland using inhabitant benthic macroinvertebrates an...

Prey selectivity habit of a cyprinodontiform killifish, Aplocheilichthys spilauchen was investigated in the laboratory to assess its potential as a mosquito control agent. In three different experimental treatments, the fish was exposed to different proportions of mosquito and chironomid larvae. The extent of selection of a given food item was dete...

To broaden knowledge of the importance of estuaries to fisheries and encourage their management, this research investigated the influence of diurnal tides and other physico-chemical factors on the assemblage and diversity of fish fauna in the Pra estuary in Ghana; an estuary highly silted by illegal gold mining activities. Fish species composition,...

New management approaches are being explored to address fisheries issues in Ghana. A collaborative research project was conducted as a proof of concept involving the Ghana Industrial Trawlers Association (GITA) and the Department of Fisheries and Aquatic Sciences (DFAS-UCC). Objectives of the research were to collect important data on the highly va...

Even though global interest in mangrove research has increased in recent years, unveiling their immense ecological and economic roles, very little work has been done to investigate the primary driving factors motivating long-term community-based mangrove restoration and management on local scales. In Ghana, policy makers and coastal management prac...

In order to enhance ecological knowledge for coastal and mangrove ecosystem conservation in Ghana, the study documents the taxonomic groups of benthic macrofauna and fish assemblages in an urban mangrove swamp as its fundamental objective with emphasis on their composition, richness and diversity. This is because benthic and fish fauna of mangrove...

In order to achieve sustainable fishing livelihoods in coastal communities, data on profitability of small-scale fisheries relative to fish species hauled and gear types used by fishermen is required as part of a broader fisheries management strategy. This study was undertaken with this in mind. Interviews were conducted among 60 fishermen between...

Abstract: In order to achieve sustainable fishing livelihoods in coastal communities, data on profitability of small-scale fisheries relative to fish species caught and gear types used by fishermen is required as part of a broader fisheries management strategy. This study was undertaken with this in mind. Interviews were conducted among 60 fisherme...

This study aims at stimulating the scientific community towards a better understanding of fish community ecology in relation to physico-chemical determinants in unmanaged coastal wetlands relevant for informed decision-making on ecosystem functioning and management in the tropical context. We investigated the diversity, size distribution and food h...

Although recent studies in Ghana show that overall poverty in coastal areas is decreasing, considerable challenges still face government and communities in their bid to improve living conditions in fishing communities. In order to achieve the goal of sustainable fishing livelihood in fishing communities, the economic conditions and actual benefits...

The use of killifish in biological control of mosquitoes to complement other mosquito control programs is gaining interest due to the increasing development of chemically resistant substrains of mosquitoes. This study investigates the ambient salinity, temperature and dissolved oxygen as well as food habits, sex ratio, fecundity and spawning freque...

This study aims at stimulating the scientific community towards a better understanding of fish community ecology in relation to physico-chemical determinants in unmanaged coastal wetlands relevant for informed decision-making on ecosystem functioning and management in the tropical context. We investigated the diversity, size distribution and food h...

The species diversity, richness and composition of fish communities as well as some physicochemical conditions were analyzed in order to establish baseline data inventory in three wetland systems in Ghana. Water quality checker was used to measure five physico-chemical parameters while a pole-seine net was used for fish sampling. Results showed tha...

The species diversity, richness and composition of fish communities as well as some physicochemical conditions were analyzed in order to establish baseline data inventory in three wetland systems in Ghana. Water quality checker was used to measure five physico-chemical parameters while a pole-seine net was used for fish sampling. Results showed tha...

The prevailing aquatic environmental conditions and their effects on the composition of the benthic macro-invertebrate community were investigated in a a few ephemeral pools in coastal Ghana along the Kakum Estuary (about 2 km west of Cape Coast; 5deg 6' N, 1deg 18' W). Water and benthic sediments were sampled every month from five pools in the wet...

Lagoons and estuaries are among Ghana's most critical habitats providing fish and other wildlife resources in support of the country's economy. In the context of climate change, it is feared that these ecosystems are faced with enormous threat. Possible impacts relate to sea level rise (SLR) that may result in widespread loss of these habitats. Lan...

This study was conducted in Domini and Amansuri Lagoons in the Western Region of Ghana in January, 2011 with the aim of assessing their physico-chemical and ecological health conditions using ecological indices e.g. richness and diversity of macroinvertebrate fauna along environmental gradients. Lagoon ecosystems have several physiographic attribut...

The prevailing aquatic environmental conditions and their effects on the composition of the benthic macro-invertebrate community were investigated in a few ephemeral pools in coastal Ghana along the Kakum Estuary (about 2 km west of Cape Coast; 5 6' N, o 1 18' W). Water and benthic sediments were sampled every month from five pools in the wetland f...