WWW.WAS.ORG • WORLD AQUACULTURE • DECEMBER 2014 13 maintained its rank as the fourth top tilapia producer, contributing 8 percent to global tilapia production (SunStar 2013). Shrimp/prawns. In the early 1990s, the Philippines ranked as the third top shrimp producing country in the world, specifically based on the culture of the black tiger shrimp P. monodon, locally known as sugpo. However, high stocking densities in pursuit of high production have led to the spread of bacteria diseases. Although initially mitigated by antibiotics, the causative bacteria developed resistance, causing the collapse of shrimp farms (Yap 1999). Culture of black tiger shrimp then waned, clearing the way for the culture of Pacific white shrimp P. vannamei, the species of current interest. Despite opposition by local NGOs and producers fearful of another disease outbreak, Pacific white shrimp are preferred for ease of culture, better survival and lower protein requirement in feeds, together leading to cheaper shrimp in the market (Sulit et al. 2005). Culture environments. Species are cultivated in fish pens, cages and ponds in marine, brackishwater, and freshwater environments. Open coastal water is the largest culture environment, mainly as a result of the seaweed industry. Mariculture began in the 1930s with oysters, followed by the culture of mussels 20 years later. However, it progressed only with the start of carrageenophyte seaweed farming in the 1970s (Yap 1999). Brackishwater areas, such as mangrove swamps and estuarine areas, is the second largest culture environment. The two main brackishwater species cultured are milkfish and black tiger shrimp; others include mudcrabs Scylla serrata, grouper Epinephelus spp., seabass Lates calcarifer and other penaeid shrimps. Freshwater aquaculture started with the introduction of Mozambique tilapia in 1950 and the subsequent spread of backyard tilapia culture throughout the country. Freshwater aquaculture came to prominence in the mid-1970s with the discovery that milkfish could be reared without feeding at commercial levels in Laguna de Bay fish pens. Thereafter, tilapia were successfully cultured in cages, initially in Laguna de Bay and then in other lakes, dams and reservoirs. Commonly cultured freshwater species aside from tilapia are bighead carp Aristichthys nobilis and common carp Cyprinus carpio, African catfish Clarias gariepinus, snakehead Channa striata, euryhaline milkfish and most recently the freshwater prawn Macrobrachium rosenbergii (Garcia and Sumalde 2013, BFARPHILMINAQ 2007, Lopez 2006). Aquaculture, Food Security and Poverty Alleviation Aquaculture has steadily contributed to the fish supply, a panacea for dwindling fish stocks from overfishing and habitat degradation. The importance of aquaculture is underscored inasmuch as fish remains the major essential protein source for the poor majority, with a 42.5 percent share of total animal protein consumption (Kawarazuka and Béné 2011) as well as the greater food insecurity experienced in rural compared to urban areas (Ravanera and Emata 2012). Pressure on the fish supply has been intensified by the impacts of climate change, as evinced by erratic weather patterns and the increasingly powerful and frequent typhoons that ravage the country. Fish farmers are highly vulnerable to loss of food and income. This was keenly felt when Typhoon Haiyan (known locally as Yolanda) wreaked havoc in the major aquaculture and fisheries producing regions in the Visayas in November 2013, leaving most small-scale fish and seaweed farmers displaced. Dependence of poor fish farmers on the fish supply is augmented by the fact that families in the lowest income groups spend more on fish products for food compared to the average Filipino household (Worldfish Center 2008). Sustainability in Aquaculture The rise of aquaculture has negatively impacted ecosystems. Proliferation of fish pens and cages has led to fish kills because of oxygen depletion, accumulation of pollutant toxins and diseases. Species have become threatened and endangered. Mangrove areas were converted to fishponds, a practice that has compromised natural filtration and has added up to water pollution (Bergquist 2007, BFAR-PHILMINAQ 2007). The Philippine government’s Mid Term Development Program (2004-2010) has identified aquaculture as a subsector that will generate new jobs and ensure food security geared toward the country’s goal of economic development (Nagothu and Ortiz 2007). (CONTINUED ON PAGE 14) Seahorse hatchery at SEAFDEC/AQD, Tigbauan, Iloilo, Philippines. Photo by J.A. Ragaza. Rearing tanks for giant freshwater prawn at SEAFDEC/AQD, Binangonan Freshwater station, Rizal, Philippines. Photo by J.A. Ragaza.
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