Anthropogrnic Stressors Induced Climate Change and Ecological Implications On Fisheries Resources in Tropics: Review

Abstract

A number of reports have shown that there is an increased in agricultural activities among the agarian populace of developing countries resulting to habitat loss and degradation as riparian forest, mangrove forest are cleared for irrigation along the major river basin, flood plains and lakes of East Africa, Tangayika, Zaire, Victoria, Chad, Amazon etc. The implication of this is that there is the concomitant increase in CO2 emission above the threshold. Since the industrial revolution, human activities have continued to lead to increased greenhouse gases in the atmosphere and now occurring at alarming levels impacting our climate, which lead to trapping heat reflected from the land and even prevent it from leaving the earth’s atmosphere making it “Warmer”. This change impacts aquatic animal altered the communities status and ocean/fresh water chemistry. This affects fish and its interactions with aquatic organism and habitat. Most aquatic animals are poikilothermic and so any change in habitat temperature will significantly influence metabolism rate, growth rate, total production, seasonality, possibly reproduction efficacy and susceptibility to diseases and possible toxins. Reported strong impact will be on the spatial distribution of fishes, their productivity and yield. The timing of flood events, drought and pollution from effluent affect water levels fluctuation which is a critical physiological trigger which affect fish migration and spawning activities. The climate change impacts are both “positive and negative” the understanding of the basic weather current trends, can be utilized to mitigate and adapt measure in the right direction to sustain, conserve and manage aquatic resources to provide food security.