Author: Aw Jeanice
Overfishing of the Bluefin Tuna
There are many ways to serve up tuna—raw, boiled, cooked, smoked, grilled, on a roll, in a sandwich, in a wrap, with mayonnaise, with wasabi, with soy sauce, just to name a few. Tuna can even be in your cat's feed with all kinds of combinations the animal-feed companies can conjure. The global demand for tuna has driven tuna fisheries along the Northern Atlantic, Pacific and Southern Ocean to thrive, and caused the tuna population to dwindle to precarious numbers.
The tuna-farming technology was introduced in 1975 to relieve pressure on natural tuna stocks. Wild tuna populations were allowed to regenerate while tuna farmers hold a certain amount of tuna and sell them instead. Tuna-farming is the practice of harvesting wild tuna and rearing them in open pens to be fattened for the markets. The tuna are kept in open sea feedlots and fed with fresh or frozen fish pieces. This essay will discuss the benefits of tuna-farming, and the Precautionary Principle (PP) (United Nations Environment Programme, 1992) will be used to analyse why tuna-farming is not sustainable and to argue that immediate attention is required to prevent irreversible serious damage to the tuna population. The tuna-farming industry reaps high profits and improves many economies, but it has inadvertently worsened the over-exploitation of fishes, and caused water pollution. However, the farming industry does seem hopeful as long as we look into solutions and improve the farming practices.
YearTotal Export Value (Millions)
Table 1: Total Export Value of Tuna-farming industry in Australia. Australian Department of Agriculture, Fisheries and Forestry; Economic Impact Report 2002/03
The tuna-farming industry generates numerous direct and indirect benefits to the local economies. Table 1 shows that the direct revenue from the tuna-farming industry in Australia grew exponentially over a decade. The Economic Impact Report 2002/03 revealed that in 2002/03, the industry also generated another $242 million from processing, transport, and downstream activities in other sectors. Such revenue has driven economic growth and infrastructure developments in the countries practicing tuna ranching.
In this multi-million dollar industry where one farmed fish may sell for more than US$100,000 in Tokyo, it is not hard to imagine that many people would hunt down schools of wild tuna to farm. However, while harvesting half-grown tuna and fattening them for the expanding Japanese market may be a golden goose for the tuna-farmers, it is a tragedy for the tuna as this may cause irreversible harm.
The initial goal of tuna-farming is similar to that of aquaculture—to relieve pressure off wild tuna populations by encouraging the trade of farmed tuna, leaving the wild stocks untouched. However, tuna-farming is the practice of rearing fish caught from wild populations to be fattened, as opposed to aquaculture where fish is raised from eggs. Essentially, tuna-farming is not very different from tuna fisheries that harvest wild tuna for trade, and therefore it certainly does not help to reduce pressure on the natural populations. To make things worse, tuna-farming has switched from farming post-spawning tuna to juvenile ones, and the harvest of tuna before they are old enough to breed is a guaranteed path toward population collapse (Ellis, 2009). This is causing a substantial reduction in the spawning population, which means smaller future populations. The economic benefits of tuna-farming attracted many countries to invest in this industry. Records show that in 2000, every country around the Mediterranean was farming tuna for sale to Japan. With dozens of countries catching hundreds of thousands of half-grown tuna that have yet to reach maturity, it is evident that the wild stocks is leaning...