Environment impact on Shrimp Agricultural: Food Market Exchange

Tutle Excluding Device ( TED )
Shrimp products imported from countries that have violated the Turtle Excluding Device (TED ) regulation are banned. According to the US Endangered Species Act (1973), the TED regulation was originally aimed at preventing the sea turtles in the US waters from being killed by shrimp trawl vessels. It has been applied to foreign shrimp vessels since 1989 and later extended to cover Thai farmed shrimp exports..

In July, 1998, the Thai government passed Revision 9 which prohibited inland freshwater farming of Black Tiger. The reasoning behind the prohibition was based on the potential damage to the the environment and ecology of rice growing areas. Because of this law, Thai shrimp farmers could not take advantage of the opportunity to increase their production to cover short supply wordwide brought about by the Ecuador crisis. Industry sources in Thailand commented that Revision 9 does not sufficiently define the areas most likely to be affected but put a blanket ban on all inland farming, which is actually an aquaculture technique that reduces the incidence of disease and damages the environment less if done right. .

The extent and nature of the negative environmental imppacts of shrimp aquaculture arise primarily from two aspects : pond contruction and operation. The severity of environmental threats increases as the number of farms increase in an area, and intensity of cultivation per farm rises. In general, modern shrimp farming is clearly unsustainable ecologically because its operational requirements vastly exceed the carrying capacity of surrounding ecosystems. Extensive, low-input shrimp ponds are typically stocked at rates between 5,000 - 20,000 postlarvae (PL) per hectare (1 hectare=2.5 acres), and can provide harvest levels ranging from 75 kg/ha to 1000 kg/ha in a year. By contrast, intensive shrimp farmers stock ponds at 250,000 to 600,000 PL per hectare, and yield from 10 to 16 tons of shrimp annually. At low density, shrimp do not requireadditional inputs for feeding, generally being able to forage on available nutrients. Beacuse the density of shrimp is relatively low, water quality is better and shrimp are less prone to disease and, hence, loss. The environmental impacts associated with the operation of these extensive systems are, thus, minimized. On the other hand, intensive, industrialized shrimp farms, while yielding higher output, are also far more costly to operate and rick prone due to high stock densities, heavy feeding rates, and the difficulty of maintaining adequate water quality and disease control. Environmental impacts are also vastly greater and more pervasive in comparison to low density operations.
* Source : Greenpeace, USA