Unsustainable Fishing Methods

Coral reefs are the world's most diverse marine ecosystem and vital for hundreds of people and animals as a resource [6]. In order to conserve reefs, the natural ecosystem must be understood and species interactions with and within the reefs must be understood. Herbivore fishes are important in the system since they help regulate processes like nutrification and sedimentation in coral reefs [9]. Restricting over-fishing on these herbivores fishes will also help reduce macroalgae, which are the major competitors of corals [9]. Unfortunately unsustainable fishing methods like blast fishing, trawling, and coral extraction are detrimental to the reef system. 

Method of blast fishing shown in the right [20]

Blast Fishing
Blast fishing is a type of fishing method that involves dynamiting the reefs to scare the fishes out into nets. This method is usually taken when the reef population has already been depleted, it's very effective but also destructive as well. An example of this has happened along the Tuticorin coast, in India, where lack of employment has led to crowded fishing grounds, and increase demand for food and declining catches compels fishers to use this fishing method [10].

Trawling

Trawling Diagram [22]

Trawling is a fishing method that involves humongous fishing nets that can range up to half an acre wide. These nets are place in the ocean and dragged for miles by a boat. The problem with these nets is that they capture everything in its way, from fishes to displacing plants and kicking up sediment that causes pollution. The catch that are consider undesirable are always thrown back to sea, but the animals are considerably displaced from their natural habitat or dead. Another issue with trawling is the structure with it, the heavy doors at the mouth of the net are used to keep it open, and drags along the seafloor, destroying the seabed. In fact, scientists have "calculated that bottom-dragging trawlers in the north Sea destroy 16 pounds of marine animals for every pound of marketable sole that is caught" [15].

Coral Extraction
On the other hand, the description of coral extraction is exactly as it sounds. This occurs in the Indo-Pacific regions of the world, especially in Indonesia and Philippines where coral reefs are the source of construction materials for many centuries [3]. Since there may be no other way to purchase or make construction materials, villagers extract corals from the coast instead.

House made of corals [21]

It is difficult to deny local villagers of the resource that their livelihoods are dependent on, but there are establish programs to moderate the amount of fishing done. The over-exploitation of the reefs must be avoided, both the physical coral and the fish species that helps build it. It has been shown that the reduction in the reef's function as a natural barrier has led to increase beach erosion and coast transformation [10].

Currently several environmental group are advocating for more sustainable fishing methods like using fishing poles, harpooning  and floating traps that does not harm the environment. Another method called trolling, is the method of hooking fish individually, it's just like the regular fishing method, except each line is anchored by the moving boat instead of being handheld (Web sunset ).

A simple way to decrease the rapid decline of the coral reef ecosystem would to stop or reduce the amount of unsustainable fishing. This is easier said than done since many coastline locals depend on fish. There has already been programs to educate locals on sustainable fishing and the importance of increasing the life of their resources. Other than that, Marine Protected Areas (MPAs) are shown to be effective in conserving the reef ecosystem.