WWW.WAS.ORG • WORLD AQUACULTURE • MARCH 2015 33 shrimp postlarvae. By 2013, production of Pacific white shrimp postlarvae (47 billion) was more than double that of black tiger shrimp (21 billion). The central provinces have 40 percent of all hatcheries and 70 percent of postlarvae production (Directorate of Fisheries 2013). This important trend indicates the modernization of technology and centralization in siting hatcheries for better management to ensure shrimp seed quality. It also indicates the increasing demand for Pacific white shrimp postlarvae (Fig. 2). For shrimp farming methods, the industry has developed and intensified with time, starting with extensive farming systems in the early 1970s, improved extensive farming systems in the early 1980s, semi-intensive and intensive farming systems since 1985, and super-intensive farming systems recently. In addition to farming shrimp in monoculture, integrated farming systems – such as mangrove-shrimp farming systems and rice-shrimp farming systems – were developed in the early 1980s and have played a significant role in the sustainable development of aquaculture in Vietnam (Quynh 1992, Preston and Clayton 2003, Nien 2005, Hai 2007, Minh et al. 2013, Tien et al. 2013; Fig. 3). Viet Nam had 230,000 ha of shrimp ponds with total production of about 56,000 t in 1991, increasing to 600,479 ha and 304,257 t by 2005, mostly for black tiger shrimp. However, Pacific white shrimp farming has developed rapidly since then, and by 2013, a total culture area of 652,613 ha and a production of 475,854 t was achieved, of which Pacific white shrimp comprised 9.8 percent of the culture area but 51.7 percent of production (Directorate of Fisheries, 2014; Table 1). The Mekong Delta is the main farming region, which accounts for over 90 percent of the culture area and 60 percent of annual production. Although there is an increasing trend toward intensification, improved extensive farming systems, integrated mangrove-shrimp farming systems and the alternative rice-shrimp farming systems remain the major systems, covering more than 85 percent of the total area in Vietnam. This is a very important strategy for sustainable development. Although shrimp farming in Vietnam is still characterized mainly by small-scale household farming, many other organizational structures have been established, such as cooperatives, entrepreneurs and large companies, operating with different systems. International standards such as organic farming, GlobalGAP, ASC and BAP have been applied and promoted accordingly. Current Status of Shrimp Seed Production Technology The technology for shrimp seed production has developed strongly during the past decades. The major technical characteristics of the two main cultured shrimp species are shown in Table 2. Tiger shrimp seed production is still concentrated in the Mekong Delta at the household scale using improved extensive farming systems, integrated mangrove-shrimp farming systems and the alternative rice-shrimp farming systems. Pacific white shrimp are produced mainly in the central provinces by large (CONTINUED ON PAGE 34) TABLE 1. Shrimp farming area and production in Vietnam (Directorate of Fisheries MARD, 2013). BLACK TIGER SHRIMP PACIFIC WHITE SHRIMP Culture area (ha) Production (t) Culture area (ha) Production (t) 2006 580,550 247,944 18,441 57,185 2008 630,408 331,234 15,079 47,827 2010 613,718 333,174 25,397 136,719 2012 613,367 301,763 41,784 186,197 2013 588,894 232,853 63,719 243,001 TABLE 2. Major characteristics of shrimp hatcheries in Vietnam (Nghị 2014, Thang 2014). Characteristics Black tiger shrimp (Thang 2014) Pacific white shrimp (Nghị 2014) Owners Private households, local companies Companies (local or foreign companies) Main producing places Mekong Delta Central provinces and Mekong Delta Capacity (m3) 48-2,800 60-6,500 Broodstock sources From wild catch Imported directly or domesticated Larval rearing systems Open or recirculating system Open or recirculating system Rearing density (nauplii/L) 100-250 150-300 Feed With or without live algae With live algae Survival (percent) 50-70 40-60 Production (million 39-172 47-1,780 PL/hatchery/yr) (11-431) (7.7-3,600)
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