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Fish is a major source of protein in human diets. Fish demand has been on the increase due to increase in human population which has resulted to wide gap between fish demand and supply. This study was carried out to elucidate the major fish species that are economically important in the study area. Assessment of fish catch composition was done in the marine artisanal fish sector of Southwest Nigeria Gulf of Guinea. The study area was divided into three strata with one sampling station selected from each stratum. Four canoes were sampled per site per month. Fish catches were sorted into taxonomic categories, counted, measured and weighed. Sixty-nine fish species from forty-two families were identified constituting fifty-nine finfish and ten shellfish species. Clupeid family had the highest contribution both by weight (40.5%) and abundance (53.7%). Sardinella maderensis was the most abundant species by number (30.6%) and weight (27.9%). Parapenaeopsis atlanticus (51%) was the most abundant shellfish while P. validus (87%) was the highest by weight. Fish production was highest in Station 1 both by weight (37%) and abundance (41%). The status of finfish species showed that five species were very common; four were common, fourteen uncommon and thirty-six rare. Among the shellfish species, three species were very common, none was common, three were uncommon and three species rare. Effective management of these fish resources is necessary to ensure fish food security. Key words : Artisanal fishery, Gulf of Guinea, species, abundance, Southwest, Nigeria.

Environmental parameters and ichthyofauna were investigated over a 2 years period in three regions along the 200 km length of Cross River. The objective of the study was to quantify the relative importance of local environmental conditions prevailing within sampling sites and the composition and abundance of the principal fish species in the upper, middle and lower reaches of the river. Vegetation cover, size of river, flow velocity, water level, temperature, transparency, and food availability explained the observed seasonal and spatial changes in fish abundance. Forty-six species and 28 genera of fish belonging to 16 families were recorded among the 14,466 fish caught. Three fish families (Cichlidae, Bagridae, and Clariidae) yielded highest number (41.3%) of species while Denticeptidae, Protopteridae, and Osteoglossidae had the least. Oreochromis niloticus, Chrysichthys nigrodigitatus, and Clarias anguillaris numerically dominated (46.4%) catch composition. Species richness was higher for the river stretch in forest area than in savanna, and it was correlated significantly with width of the reach, water transparency, depth, and flow velocity (P 0.6) and had higher richness (>9.7) than those for dry season. Wet season and forest regions were therefore critical in maintaining fish stock of Cross River.

The multivariate relationship between fish species and environmental variables was studied at three landing sites along the coast of the Gulf of Guinea, Southwest Nigeria. Fish species were sampled for abundance once per month per site for twenty-four months and eight environmental variables were measured. Five fish species (Sardinella maderensis, Ilisha africana, Pentanemus quinquarius, Chloroscombrus chrysurus, Ethmalosa fimbrata and Pterioscion peli) were observed to be very abundant, which contributed 77.6% of the total abundance. Fish species composition depicted tropical waters fishery with few dominant species having large number of individuals. Dendogram of cluster analysis revealed five fish communities. Canonical correspondence analysis was used to elucidate the relationships between assemblages of fish species and their environment. S. maderensis, the most abundant species, was observed to be influenced by pH, total dissolved solids (TDS) and nitrate. Clustering and ordination techniques provided very similar results based on the fish species composition. Water pH, total dissolved solids (TDS), nitrate and conductivity were shown to be most influencing environmental variables in decreasing order of vector projections, influencing fish assemblages in marine coastal waters of the Gulf of Guinea, Southwest, Nigeria., Ovim istraživanjem proučavan je multivarijatni odnos vrsta riba i varijabli iz okoline na tri mjesta duž obale Gvinejskog zaljeva u jugozapadnoj Nigeriji. Uzorci riba prikupljani su jednom mjesečno na odabranim lokacijama tijekom 24 mjeseca, pri čemu je mjereno i osam varijabli iz okoline. Najčešće vrste riba, sa 77,6 % udjela ukupne riblje populacije, bile su: Sardinella maderensis, Ilisha africana, Pentanemus quinquarius, Chloroscombrus chrysurus, Ethmalosa fimbrata i Pterioscion peli. Sastav ribljih vrsta prikazuje ulov u tropskim vodama s nekoliko dominantnih vrsta koje imaju veliki broj jedinki.. Dendrogram klaster analize prikazuje pet ribljih zajednica. Kanonička korelacijska analiza korištena je kako bi se razjasnio odnos između sastava vrsta riba i njihove okoline. Utvrđen je vidljiv utjecaj pH, ukupnih otopljenih tvari (TDS) i nitrata na S. maderensis, najbrojniju riblju vrstu. Tehnike grupiranja i koordinacije dale su vrlo slične rezultate temeljene na sastavu ribljih vrsta. pH vrijednost vode, ukupne otopljene tvari (TDS), nitrati i provodljivost najutjecajnije su varijable okoline u opadajućem redoslijedu vektorske projekcije, a znatno utječu na riblji sastav u moru na obalama Gvinejskog zaljeva u jugozapadnoj Nigeriji.

Studies were conducted on the growth and mortality parameters, recruitment pattern, probability of capture, yield-per recruit, and present rate of exploitation of the African river prawn, Macrobrachium vollenhovenii from Dawhenya impoundment, Ghana. Estimation of the von Bertalanffy growth parameters gave; L∞ = 14.2 cm, K = 1.0 yr -1 , and to = -0.195 yr -1 with the growth performance index, Ф' of 2.303. From the linearised length-converted catch curve, total mortality, Z was 5.36 yr -1 . Natural mortality, M calculated from Pauly’s empirical formula was 2.20 yr -1 and fishing mortality, F calculated from Z - M was 3.16 yr -1 . From the mortality estimations, the present rate of exploitation, E calculated from F/Z was 0.59 indicating that, the species is on the verge of being over-exploited in the impoundment. Using the estimated value of the growth coefficient, K, the longevity was found to be about 3 yrs. Estimations from the probability of capture routines gave the length-at-first capture, Lc as 3.07 cm while the size distribution of the catches suggest two recruitment pulses in a year. It is therefore recommended that, the property right-based system for fisheries management should be implemented so that fishermen can cooperate in the management of the Macrobrachium fishery.

Some aspects of the chemical and anatomical weight composition of shrimps in Nigeria's Coastal Waters were analysed with a view to obtaining the flesh yield, waste yield and their utilization potentials. The four most abundant shrimp species in Nigeria's waters were selected for the study. Proximate analysis of the species [ Macrobrachium rosenbergii (freshwater); Palaemon serratus (brackishwater); Panaeus notialis and Parapenaeopsis atlantica (marine)] was carried out on the flesh, shell and head. The moisture content of the flesh varied from 71·57±0·33% in Palaemon serratus to 75·95±0·16% in Parapenaeopsis atlantica . The protein content varied between 26·30±0·34% and 22·35±0·30% in flesh of all the species. Fat content was generally low, ranging between 0·79±0·03% and 1·11±0·18%. Crude fibre was below 0·06% in the flesh of all the species. The concentrations of calcium, magnesium, potassium, sodium, phosphorus, manganese, copper, iron and zinc were determined in the head, shell and flesh of the four species. The head was consistently higher than the shell and flesh in the levels of the various elements. Anatomical fractionation showed the head was about 33% of the total weight while the head-off portion was about 66%. The total flesh yield obtainable from the shrimps was 51% and the waste yield was 49%. The possibility for processing shrimp waste into shrimp meal and single cell protein is discussed.

It has been considered that the impacts of climate change are likely to be considerable in tropical regions. Developing countries are generally considered more vulnerable to the effects of climate change than more developed countries. This has been attributed to a low capacity to adapt in the developing countries. Fisheries and aquaculture are threatened by changes in the earth atmosphere and ocean, such as increasing global surface temperature, rising sea levels, increases in incident UV radiation, irregular changes in average annual precipitation, and increases in the variability and intensity of extreme weather events. Greater climate variability will surely complicate the task of identifying impact pathways and areas of vulnerability requiring research to devise and promote coping strategies and improve the adaptability of fishers and aquaculturists especially in the developing countries. Many coastal and island communities where poverty is widespread and livelihood alternatives are limited depend heavily on fish resources for their well-being. Fish also provides an important source of cash income for many poor households especially in Africa. This paper examines the ways in which climate change and extreme events may directly affect fisheries and aquacultural production in Africa. Specifically the paper looks at the effects on African river fisheries, coastal fisheries, coral reefs and mariculture. It presents the implications for this important sector on the people, resources and the environment. The paper recommends (a) the strengthening of capacity including that of African scientists, governments and civil society; (b) supporting adaptation by rural /urban people particularly the most vulnerable and (c) adding value to existing adaptation initiatives to enable African scientists to apply expertise and carry out research in support of adaptation projects in land-water interface ecosystem. Introduction Climate change is environmental change, but given that human societies are affected directly and indirectly by the climate system – and given that human activities are driving climate change – it is fundamentally a human problem. Climate change cuts across boundaries. The impacts of climate change are expected to seriously (and disproportionately) affect the livelihoods, health, and educational opportunities of people living in poverty, as well as their chances of survival, both locally in specific areas and globally in general. As a global environmental challenge, the drivers of which are inextricably linked with highconsumption lifestyles, climate change lies firmly outside the sphere of influence of poor communities and poor countries, which have little say in how the challenge will be addressed. Those with special burdens and/or vulnerabilities such as women, ethnic minorities, and people living with HIV/AIDS are feeling yet another pressure in global warming – one that is fundamentally unjust. The impacts of climate change will affect everyone; some have calculated that the costs associated with overcoming climate impacts could even exceed global economic output within a few generations.