Mon, Jul 13th 2009, 12:22

Aquaculture is widely regarded as the answer to the world’s problem of depleted fish stocks, but this does not come without a cost. Aquaculture comes with its own set of problems.

Threat to Wild Populations
Many captive fish escape from aquaculture holding systems and return to the wild. In many places the escaped fish are competing with wild fish, competing for food and affecting the natural life cycles.

Disease
Escapees are infecting wild stocks with parasites and disease. Many exotic diseases spread in the high density aquaculture environment, compounded by pathogens that are being introduced by aquaculture products bought in. These diseases spread to animals in the wild threatening future populations.

Overfishing
Ironically, while Aquaculture is supposed to be the answer to the global problem of overfishing, it is actually adding to it. Aquaculture requires tons of food for the fattening of captured fish and other seafood. It has been noted that one third of the global fish catch is used to make fishmeal and fish oil ... and the aquaculture industry uses nearly 90% of the supply of fish oil and over 50% of the supply of fishmeal. The species used for these products are themselves already critically overfished and this increased demand is adding extra pressure on these fish stocks.

Pollution
Large scale aquaculture operations use public coastal areas for their operations. The waste products produced by these dense "feedlot" populations seeps into the surrounding seawater altering the ecosystems, encouraging the growth of toxic algae and causing oxygen depletion.

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