Potential Impacts of Climate Change on Artisanal Fisheries of Nigeria

Abstract

Artisanal fisheries contribute to sustainable livelihoods of people in several ways accounting for more than 80% of total fish production in Nigeria. Climate change arising from global warming, increasing temperature, stratification and changes in ecosystem processes brings flooding, precipitation, evaporation, run-off and flow with potential serious negative impacts on fish assemblages and productions, fishing activities, fishers catch per unit effort, fish breeding, morphology, resistance to species invasion, wild fish seed supply, fish meal and oil and likelihood of spread of vector-borne diseases. Climate change could also extirpate fish population in lakes. Fishing gears, fishing processing and marketing, fishing periods could be affected and at the extreme total abandonment of artisanal fisheries could occur on account of climate change. Understanding climate change and its impacts on the ecosystem will provide accurate decision, capacity building and adaptive management in tackling the problems as it will provide practical, scientific, technical and socio-economic actions to mitigate the challenges currently and in the future. Study of vulnerability of artisanal fisheries to climate change in the likelihood of episodic events of risk exposure, sensitivity and adaptive capacity should be the focus of scientific research in this decade. Climate change will produce synergistic and cumulative effects with considerable uncertainty to the extent, magnitude, rate and direction of changes and impacts. Thus, high confidence predictions models of climate change perturbations on fish response in terms of feedbacks, critical thresholds, adaptations, migrations, breeding, and recruitment and so on could mitigate the impacts and ensure sustainability of artisanal fisheries in Nigeria. Alterations in their food-web processes and interactions, species invasion and spread of vector-borne diseases could also result from the effects of CC. Rosenzneig [7] reported that surface water temperatures have warmed by 0.2 to 2°C in lakes of Europe , North America and Asia with stratified periods advanced by up to 20 days and lengthened by 2-3 weeks. This is also true in Africa as a result of increasing gas emissions. Since fish are cold blooded, they are very sensitive to temperature changes. Any increase in temperature above the tolerance limit in their habitat will surely have serious negative effects on fish physiology especially in the supply of oxygen to their tissues. CC will impact on the spawning success of fishes spatially and temporally. This is because time and locations of spawning of several species of fish are linked to physical conditions such as temperature, currents etc, as well as biological factors like food. Changes in these conditions on account of CC would therefore impact negatively on the spawning of fishes in these habitats. Likewise, food and feeding of fish would be affected as plankton production in aquatic ecosystem is linked to physicochemical variables of the ecosystem which could be seriously ...

Growth Performance and Body Compositions of Clarias gariepinus Fed Graded Levels of Detoxified Jatropha curcas meal

“…Fish has been reported to be a good source of food and means of livelihood to many African populace [1]. However, this industry is constrained by availability of alternative nutritive protein source as replacement for fish meal [2,3] Naylor et al Several studies conducted have revealed the use of some plant protein sources like Moringa leaf meal, Soybean meal and so on as fish meal replacement in fish diets [4][5][6][7][8][9][10][11].…”