World Aquaculture - December 2014

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• 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 mudcrabsScylla 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, BFAR-
PHILMINAQ 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).
( C O N T I N U E D O N P A G E 1 4 )
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.