Most people that eat shrimp are unaware of where it comes from and about the impacts its production implies. Most of the commercial shrimp is either caught wild using destructive fishing methods, or produced in industrial shrimp ponds, which constitute the main cause of mangrove destruction.
According to FAO figures, 50% of the world’s fisheries are already depleted. Jacques Diouf, General Director of FAO, has just alerted the delegates of more than 70 countries at a conference recently held in Iceland that oceans are over exploited and that it is urgent to guarantee their sustainable use. According to FAO data, in 1950 the total production of fish was 19 million tonnes. Fifty years later, a slightly higher amount (20 million tonnes) was wasted in the process of producing a total of 130 million tonnes.
Shrimp trawlers are among the most wasteful fishing boats in the world: they produce less than 2 % of the world’s seafood, but are responsible for a third of the wasted fish bycatch. Up to 14 pounds of fish and other marine life are destroyed and discarded for each pound of shrimp harvested. Shrimp trawlers kill more turtles than all other human means combined in US waters.
This needless destruction is not much better in the case of shrimp farming. Shrimp aquaculture ponds are located in the most biologically productive and undervalued areas on earth: coastal estuaries, mangrove forests and wetlands, where shrimp naturally grows. Pond construction begins by cutting down the mangrove forests and digging diked ponds. Then, they are stocked with post larvae, mostly from hatcheries and nurseries at high stocking densities. In order to force the shrimp to feed continuously, the pond is lit all night. It is fed with formulated protein pellets and supplementary artificial feeds. To prevent from diseases, a number of chemical inputs as antibiotics, pesticides and detergents are also added. Pumped exchanges of water to remove wastes and to add clean oxygenated water is crucial to accommodate the high density stocking. This results in accumulation of wastes and degradation in the surrounding ecosystems leading to severe and irreversible problems.
In the short term, intensive shrimp farming is highly profitable for the companies. However, it is clearly unprofitable for the local communities living in the area where it is established, which results in major environmental and economic losses for the local people.
This destructive and polluting system can be avoided. Aquaculture has not always inflicted environmental harm. In fact, integrated fish and rice farming has been the backbone of traditional agriculture in Asia for centuries. This traditional system offers enormous potential for local food security and household nutrition. They also take advantage of the services that coastal ecosystems provide, such as filtering and purifying water, cycling nutrients, removing contaminants and buffering the land from coastal storms and severe weather. A study of the Matang mangrove in Malaysia revealed that its value for coastal protection alone, exceeded the value of farmed shrimp by 170 percent.
Silvofishery, an ancient coastal resource management concept might prove invaluable as alternative management. Silvofisheries is a low input sustainable aquaculture form of integrated mangrove tree culture with brackish water aquaculture. This integrated approach to conservation and utilization of the mangrove resource allows for maintaining a relatively high level of integrity in the mangrove area while capitalizing on the economic benefits of brackish water aquaculture.
However, it is important to underscore that the issue is not a technical one and that there are basically two ways of producing shrimp. One is based on the appropriation and destruction of mangrove areas, the pollution of the same and neighbouring areas and high corporate profitability at the expense of local peoples' territories and livelihoods. The other approach aims at the sustainable use of natural resources --among which shrimp is but one-- for the benefit of local communities. If environmental protection and social advancement is to have a meaning, the latter system is clearly in the right direction.
