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, …show more content…
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,