World Aquaculture 51 uted at high latitudes, mainly in the Atlantic but also in the Pacific. It is considered to be the subspecies Pandalus borealis eous. Northern prawn prefer clay and mud bottoms in seawater at depths between 20 and 1,380 m. The species is exclusively used for human consumption. The Atlantic species is medium sized with females reaching 165 mm. It has great commercial value and is fished on both sides of the Atlantic, where more than 20 countries take part in the fishery. In the Greenland area, it is the most important species in the fishery. In the northeastern Atlantic, Norway and Iceland take the largest portion of the catch, while on the other side of the Atlantic, Canada and Greenland take most of the catch. The catch seems to increase in the NW Atlantic off the northern coast of America and Greenland, while they decrease on the European side (Figure 2). Increasing catches on the northwestern side of the Atlantic can be explained by decreasing predation pressure from cod, which have disappeared from some areas. The shrimp are fished by trawlers at depths from 50 to 500 m. Common shrimp (Crangon crangon) is a less important species compared to northern prawn. It is mainly fished in the North Sea area by two countries, Germany and the Netherlands (Figure 3.) There are also small catches in other areas, including the Black Sea. The species occur on sandy and muddy bottoms from shallow areas down to 150 m. It can reach a size of 90 mm, but it is often smaller. It is peeled and usually sold frozen or in brine. It is used for human consumption and for industrial purposes, mainly as an ingredient in pelleted feed. Akiami paste shrimp (Acetes japonicus) is of great commercial value in the northwestern Pacific. China dominates the fishery and caught 670,000 t in 2004. Rather small catches were also taken by the Republic of Korea (Figure 4), but it was also fished in many other countries, although the catches were not reported to FAO. Various authors have reported that the species was also caught in Viet Nam, Thailand and Malaysia (Holthuis 1980). Its geographical distribution is, thus, large in many parts of Asia. It occurs in shallow water above muddy bottoms. The male can reach a total length of 24 mm and the female 30 mm. The tiny shrimp is made into shrimp paste or powder. It is also farmed. In some years, the quantity harvested has been around 3,000-4,000 t. Another important species is southern rough shrimp (Trachypenaeus curvirostris). The species has a wide distribution from China and Japan in the north to Australia in the south and in many areas as far to the west as south Arabia. It occurs from 30-150 m. The species prefers muddy sand bottoms and water from 13-150 meters (Dore and Freemoth 1987). The species reaches a total length of 81 mm for males and 98 mm for females. The reported catches in 2003 were more than 400,000 t, up from 300,000 t in 2004 (Figure 5). The species is mainly fished by China. In Japan, it is used for both human consumption and for bait. The Farming of Large Tropical Shrimp Species: How it started Several hundred years ago, shrimp started to be cultivated in Asia. From the beginning, the methods were Fig. 4. The reported catches of Akiami paste shrimp ( Acetes japonica) has increased very much during later years. The catches since the end of 1990s are now in the magnitude of 600 000 tons according to FAO catch statistics. Fig. 5. The catches by Southern rough shrimp ( Trachypenaeus curvirostris) reported to FAO. Whiteleg shrimp ( Litopenaeus vannamei) originates from the eastern Pacific outside South America where it is cultivated above all in Ecuador. This species has been introduced gradually in Asian aquaculture since 1995. In 2004 China produced 735,000 tons, followed by Thailand with 276,000 tons. (Photo by Granvil Treece)
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