The Effects Of Overfishing And Overexploitation Of Fishery Species

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A fishery is a broad term used to describe any activity involving the harvesting of aquatic and marine animals, mainly fish. A fishery can refer to the fishing vessel, equipment and crew involved in the harvesting; the area that the fishing activity occurs in; and/or the species of interest. These can be wild captured seafood or seafood harvested through aquaculture. Commercial fisheries can also refer to the whole process of catching, processing and marketing the seafood for sale and involves the entire business of harvesting seafood. (Blackhart, Stanton & Shimada, 2006). It applies to both recreational, commercial and subsistence harvesting of aquatic animals. The term generally refers to specific species of interest such as salmon fisheries, …show more content…
All of these will be explained in more detail below.

1. Overfishing and Overexploitation of Fishery Species and their Effects on the Ecosystem
According to Blackhart et al. (2003), overfishing refers to reducing a population stock to a threshold level below which the stock can recover from. It means that the rate of fishing mortality may be greater than the rate at which the population can reproduce, this greatly affects the sustainability of harvesting the fishing stock because continuing to overfish in such a manor hinders the population’s ability to recover and may become depleted or locally extinct. This leads to a significant reduction in the biomass of a population (FAO,
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Each animal has its place in the food web and affects the trophic levels of an ecosystem. Animals lower down in the food chain such as the herbivores and planktivores affect the organisms higher up in the food chain because they are usually food for the predatory animals. They also compete for food with other organisms in the same trophic level thereby maintaining balance. The same goes for the predators at the top of the food chain, they control the prey species and keep them from over growing (Garcia et al, 2003). This can also impact on the assemblages associated with the environment as removal of predators may cause abundant growth of lower trophic species which cause over-feeding on coral reefs and sponge aggregations at an accelerated rate (NOAA,

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