Organized by SEAFDEC Aquaculture Department with funding from the Government of Japan, the 3-day International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia aims to promote and augment regional initiatives on resource enhancement and sustainable aquaculture practices, and to contribute to poverty alleviation, livelihood and food security.

Recent Submissions

  • Book | Conference publication

    Resource enhancement and sustainable aquaculture practices in Southeast Asia: challenges in responsible production of aquatic species : proceedings of the international workshop on resource enhancement and sustainable aquaculture practices in Southeast Asia 2014 (RESA) 

    MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.) - 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    The conference was held in order to promote and augment regional initiatives on resource enhancement and sustainable aquaculture practices, and to contribute to poverty alleviation, livelihood and food security in Southeast Asia. The contributions of the selected participants during the conference which are contained in this volume are cited individually.
  • Conference paper

    The importance of mangroves to capture and culture fisheries 

    JH Primavera - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Abstract only.
  • Conference paper

    Stock enhancement? Why bother 

    J Ingles - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    There are two approaches to resource enhancement of depleted wild fish stocks: through stock enhancement where aquaculture science plays a central role, or through improved management of fish stocks. This paper presents an argument that despite major advances in stock enhancement technologies (tagging, genetic mapping, numerical modeling techniques), major hurdles in policy framework, science and information gaps, risk mitigation protocols and capacity gap remain. These factors are associated with high and recurring cost that requires medium to long-term solutions that ultimately, improving management and governance to recover depleted stocks will still be the best option available.
  • Conference paper

    Status of resource management and aquaculture in Malaysia 

    A Yusoff - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Malaysia is a maritime nation and its fishing industry is a source of income for 134,000 fishermen. In 2012, the fisheries sector produced 1.7 million tons of fish valued at RM10.8 billion and generated trade worth RM6 billion. The landings from capture fisheries are expected to increase from 1.32 million tons in 2010 to 1.76 million tons in 2020 at an annual growth rate of 2.9%. In 2012, 65% of total catch was contributed by the coastal fisheries as compared to 35% from deep sea fishing. Landing from deep sea fishing is expected to rise from 381,000 tons in 2012 to 620,000 tons in 2020. Deep sea fishing has been identified for its potential to contribute to the increase in the country s fish production. With a growing population and an increasing preference for fish as a healthy source of animal protein, the National Agro-food Policy (2011-2020) estimated that the annual demand for fish will increase to 1.93 million tons by the year 2020. The Department of Fisheries (DOF) has developed the Capture Fisheries Strategic Management Plan (2011-2020) based on three main documents i.e.; National Agro-food Policy (NAP, 2011-2020), Department of Fisheries Strategic Management Plan (2011-2020), and Malaysia National Plan of Action on Sustainable Fisheries for Food Security towards 2020.

    Aquaculture is now being promoted in Malaysia as an important engine of growth and eventually to become the mainstay of the nation s economy. Situated in a region with abundant supply of land and water, two determinant factors for aquaculture activities, Malaysia has always strived to ensure that this sector is not sidelined in their development efforts. With a growing population and an increasing preference for fish as a healthy source of animal protein, it has been estimated that the annual demand for fish will increase to 1.7 million tons in 2011 and further to 1.93 million tons by 2020. From the present annual aquaculture production of about 525,000 tons, this output would need to be raised to 790,000 tons to meet the projected demand by 2020. In a move to develop the aquaculture industry, the DOF, has initiated the Aquaculture Industrial Zone (AIZ) Program involving the development of 49 zones, located across Malaysia, which will be used for culture of various types of high value aquatic species. The DOF has identified several strategic areas that would be developed for downstream activities such as fish seed production, feed mills, fish processing plants, and other supporting industries. Aquaculture is also currently listed amongst the 16 Agro-food s Entry Point Projects (EPP) of the National Key Economic Area (NKEA). The government aims to double the Agro-food sector s contribution to Gross National Income (GNI) from Malaysian Ringgit (RM) 20.2 billion in the year 2010 to RM49.1 billion by 2020, or an increase of RM28.9 billion.
  • Conference paper

    Larval rearing of silver therapon (Leiopotherapon plumbeus) in outdoor tanks 

    FA Aya, VSN Nillasca, MNC Corpuz & LMB Garcia - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Silver therapon (Leiopotherapon plumbeus, Kner 1864), locally known as ayungin, is an important freshwater food fish species found in Laguna de Bay, the largest lake in the Philippines. Its market price is twice that of other most sought after freshwater fishes such as tilapia and milkfish. However, intense fishing pressure on the species has significantly reduced the wild stock in Laguna de Bay. Studies to develop hatchery techniques for this indigenous freshwater fish species are therefore needed to produce seedstock for possible culture and wild stock rehabilitation.

    This study highlights the successful larval rearing of silver therapon in outdoor concrete tanks. Larvae reared in outdoor tanks with natural food (grown two weeks beforehand) reached the juvenile stage (40 days after hatching (DAH)), suggesting the presence of some suitable live food organisms in pre-conditioned rearing water. However, larval survival rates were low (11.58 ± 6.56% at stocking density of 0.9 larvae l-1), which is probably linked to the density of food items, particularly during the onset of exogenous feeding or due to high stocking density of larvae. To improve the availability of natural food for the larvae, fertilization of the rearing water in the outdoor tanks stocked with larvae at two densities (0.4 and 0.6 larvae l-1) was performed. Larval growth and survival were improved at stocking density of 0.4 larvae l-1 than at 0.6 larvae l-1. Diet composition of first-feeding silver therapon larvae in outdoor tanks inoculated with cultured microalgae (Chorella sorokiniana) and zooplankton was also determined. Larvae were able to consume rotifers and some phytoplankton beginning at 2 DAH and larger preys such as cladocerans and insect larvae starting at 12 DAH.

    The efficacy of raising silver therapon larvae in outdoor tanks using ambient lake water was also evaluated. Larvae reared in ambient lake water grew well but survival (48.44 ± 7.85%) was significantly improved in treatments where tropical almond or talisay Terminalia catappa leaves were added during the first two weeks of larval rearing.
  • Conference paper

    Potential genetic impacts of hatchery-based resource enhancement 

    ZU Basiao - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    The global population according to the United States Census Bureau has reached 7 billion as of October 2013. The continuous growth in human population will continue to put tremendous pressure on food production. The demand for fish as source of good protein is no exception. In 2011 total capture fisheries supplied 90.4 million tons of food and total aquaculture provided 63.6 million tons. While aquaculture production has increased dramatically, more than 50% of fishery production still depends on capture fisheries. Overexploitation of wild fish stocks has become one of the biggest problems in global fisheries. Stock enhancement has become a potential viable strategy for marine fisheries in danger of collapse. With the tremendous progress made in the breeding and larval rearing techniques of marine species, hatchery-based stock enhancement is now operated in many stock enhancement programs. However, many questions are raised in the use of hatchery-reared fish in stock enhancement. This paper will discuss genetic considerations in stock enhancement in developing countries.
  • Conference paper

    Good aquaculture practices (GAqP): setting directions for harmonized regional standards - the Philippine experience 

    MF Matubang & NA Lopez - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    A milestone process on how Good Aquaculture Practices (GAqP) emanates in Philippine aquaculture and its integration to the ASEAN harmonized standardization efforts is discussed in the paper. The management model, value chain and draft Philippine National Standard of the GAqP code are presented and evaluated as to its impact to trade and marketing, socioeconomic considerations, food safety and technology.
  • Conference paper

    Assessment of humphead wrasse (Cheilinus undulatus), spawning aggregations and declaration of marine protected area as strategy for enhancement of wild stocks 

    FG Romero & AS Injaki - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Humphead wrasse, known as the Napoleon fish (Cheilinus undulatus), is the largest living member of the family Labridae. It is slow growing but can grow to a maximum size exceeding 2 m and 190 kg. This species was the first commercially important coral reef food fish to be listed in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix II in 2004 because of its vulnerable status and the ongoing threat to its conservation from international trade. Like many coral reef fishes, the humphead wrasse, Cheilinus undulatus, aggregate in reef areas when they spawn and this spawning behaviour makes them highly vulnerable to overfishing. Assessment of the spawning aggregations of this species was conducted in the municipalities of Sibutu and Sitangkai in the province of Tawi-Tawi, Philippines. Key informant interviews (KII) with fishermen, mariculturists, and other stakeholders and focus group discussions (FGD) with local government leaders, Fisheries and Aquatic Resources Management (FARMC) members, mariculturists, and exporters were conducted. Guided by the results of these KII and FGDs, underwater visual census of mameng (local common name for Napoleon wrasse) populations (juvenile and mature) were conducted to document spawning aggregation sites. Since there was no photo-documentation of actual spawning aggregations of mameng in the reef areas, indirect measures were used. Result of the KII and FGD indicated that the Baligtang Reef in Sipangkot and Tando Owak are major sources of spawners. Anecdotal accounts of Bajau fishermen showed that Dungun Dungon, Baligtang reef, Tando Owak and Tugalan are traditional fishing grounds for mameng spawning aggregations. From the length-frequency analysis of mameng caught by hook and line and fish pot in the Baligtang Reef in Sipangkot, the estimated length at maturity of this species was found to be 25-35 cm. There were 134 individuals caught within this size range so they are considered potential spawners. Another indirect proof used was the underwater documentation of juvenile humphead wrasse which were regularly observed and photographed in association with seagrass beds and branching coral reefs in Baligtang Reef in Sipangkot, Sitangkai. Gonadal study also indicated that the mameng caught in this area had mature and ripe gonads but the number of mature fish depends on the season. These were the basis of declaring Spawning Aggregation Sites in Tando Owak and Dungun Dungun in Sibutu and Baligtang Reef, Sipangkot and Tugalan in Sitangkai. These were declared as marine protected areas by ordinance of the municipal Sangguniang Bayan of the two municipalities. Management and enforcement plans have been developed and Bantay Dagat have been trained to protect the spawning aggregations and this strategy aims to protect the wild stocks of humphead wrasse. Protecting the spawners would ensure that there would be enough recruits, prevent recruitment overfishing and enhance the wild stocks.
  • Conference paper

    Social preparations towards community-based approach to stock enhancement in Sagay Marine Reserve, Philippines 

    ND Salayo, RJG Castel, DHM Tormon, RT Barrido, MFJ Nievales & T Azuma - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Stock enhancement involves a set of management approaches which include the release of hatchery-produced aquatic organisms to enhance or restore fisheries. Stock enhancement of various species has a long history in developed countries and it showed that releases have the potential to yield substantial benefits for various fishery stakeholders. While the biological objectives of stock enhancement were often successfully achieved in most of these enhancement initiatives, some results showed that actual social gains in terms of yields, distribution of benefits and institutional sustainability are often inconclusive. The high cost of stocking accrues to the government which means these are supported by public funds. Meanwhile, benefits are dissipated across various stakeholders, some of them did not at all contribute and participate in the stocking program. In such government-initiated and publicly-funded stock enhancement programs, the lack of sense of stewardship among direct fishery stakeholders was observed to have contributed to a vicious cycle of excessive extraction of fishery resources for individual economic benefits.

    Developing countries such as the Philippines would be confronted by budgetary limitations if it has to adopt the stocking strategies applied in developed countries. Thus, with reference to the success of co-management approaches for managing fishery resources in the Philippines, a community-based strategy for enhancement of fishery stocks was explored. SEAFDEC/AQD, with support from the Government of Japan Trust Fund, initiated a community-based approach to stock enhancement in Molocaboc, an island barangay or village within the Sagay Marine Reserve (SMR). The initiative aims to ensure that its goals and strategies are within the social milieu of local stakeholders, i.e. fisherfolks are without financial assets to contribute or pay for the enhancement of the fishery and stock enhancement is often not a priority approach to address fishery resource depletion for most local governments. However, the social assets of fishing communities could be explored to implement stock enhancement. This paper describes the social preparation executed from 2007 to 2011 in order to orient a fishing community such as Molocaboc towards a successful enhancement of overfished species. Initially, the project focused on donkey s ear abalone Haliotis asinina to provide an example for other species. Abalone or kapinan in the vernacular is one of the over-extracted fishery resources in Sagay City. It is one of the high-priced catch among fishers in coastal communities in the Philippines. High buying prices compared with other fish catch motivated small-scale fishers to target abalones and caused its overfishing.
  • Conference paper

    Resource assessment of sea cucumber in northern Iloilo, central Philippines 

    PA Alpasan & RA Billones - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    A resource assessment of sea cucumber was conducted in six out of eight coastal towns in northern Iloilo, a fisheries rich area facing the Visayan Sea in the central Philippines. A yearlong assessment was conducted in 2012. Fishery dependent survey was done with the use of survey questionnaire translated into dialect. Six trained enumerators administered the questionnaires to 114 gatherers and 18 local traders. Fishery independent survey involving Belt Transect Method (BTM) for intertidal areas and Timed-Search Method (TSM) for subtidal areas were conducted in 21 GPS (Global Positioning System)-referenced sampling stations. Sample specimens were also collected and prepared for taxonomic identification. External morphology, internal structures (dissected samples) and spicule analysis were used in the identification.

    Fishery dependent survey showed that gleaning (40%) is the most dominant extraction method used. Various methods were also employed including the dangerous compressor diving and the destructive karas, a method using a rake-like device to scrape the sea bed. In terms of volume, the most heavily exploited sea cucumber belongs to the Stichopus groups. The trade of sea cucumber is dominated by island-based traders. Almost half of the traders are women, signifying that trading is a woman's domain as well. Derived monthly income from sea cucumber trade ranges from PhP 2,000-3,000 for gatherers and PhP 2,000-5,000 for the traders.

    Fishery independent survey resulted in the identification of six sea cucumber genera (Bohadschia, Holothuria, Paracaudina, Pseudocholochirus and Stichopus). Of the 32 species found belonging to the six genera, only 16 were identified up to the species level. Samples of unidentified specimen were sent to the University of the Philippines - Marine Science Institute (UP MSI) laboratory for molecular taxonomic identification. In terms of species count, the most dominant genera is the Holothuria with nine identified and seven unidentified species. H. impatiens is also the most dominant sea cucumber found in the area. Further, the recorded catch per unit effort (CPUE) for fishery-independent survey is 3-4 pcs/diver/hr.

    The resource assessment showed that the trade of sea cucumber is dictated by economic value rather than by ecological abundance. While the scale and extent of sea cucumber fishery in northern Iloilo is small-scale and island based, the study highlights the need for trade regulation and stock enhancement of heavily exploited species as extraction affects the ecological distribution of sea cucumber stocks in the area.
  • Conference paper

    Development of a simple, rapid, cost-effective diagnostic kit for WSSV 

    PMT Arabit, ADD Nicolasora, PEZ Go, CMA Caipang & MBB Maningas - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Shrimp aquaculture is one of the most important sources of income and livelihood in the Philippines. For the past two decades, the white spot syndrome virus (WSSV) has adversely affected the production of the Philippine shrimp industry resulting to losses in revenue. Shrimps infected by the virus experience up to 100% mortality, 3 to 10 days post-infection. One way of controlling the disease is early detection, which remains to be too complicated and inaccessible to shrimp farmers. Being a DNA virus, the first step to WSSV diagnosis is the isolation of high-quality DNA suitable for polymerase chain reaction (PCR) or loop-mediated isothermal amplification (LAMP). Using readily available and affordable reagents, a DNA extraction protocol has been especially developed for rapid WSSV-detection; DNA has been successfully extracted from the pleopods of shrimps and the results were comparable with that of commercially available kits from Promega and Zymoresearch. LAMP has been optimized for WSSV detection in the temperature range of 55°C to 68°C and was shown to be faster and ten times more sensitive than conventional PCR. This study together with a locally fabricated machine, offers a more convenient, practical and efficient way of detecting WSSV, with the advantage of using non-invasive means of obtaining shrimp tissue therefore not losing any shrimp meat in the process.
  • Conference paper

    Optimization of feeding and growth conditions for hatchery-bred larvae of indigenous Philippine silver perch, Leiopotherapon plumbeus (Perciformes: Terapontidae) 

    JA Añano, F Aya, MN Corpuz & MRR Romana-Eguia - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    The Philippine silver perch, locally known as ayungin, is an endemic fish species and is considered as a potential candidate for aquaculture and for stock enhancement. However, high mortality associated with early larval stages presents a significant bottleneck to its latent commercialization. Culture experiments considered interactions among prey proportions, growth conditions and their consequences on fish growth performance and survival. Two phases of the experiment were conducted: (1) a short duration feeding trial utilizing different prey proportions of Brachionus calyciflorus and Moina macrocopa and (2) an indoor larval rearing technique that ensured optimum growth and survival of juveniles. Findings of this research will be used to propose an efficient rearing strategy addressing the aquaculture of this indigenous species.
  • Conference paper

    Is small-hold tropical aquaculture in a genetic plunge towards extinction? 

    RW Doyle - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Tropical shrimp aquaculture is in a disease-induced crisis of lost production. The response to this crisis currently focuses on microbiology and pathology, quarantine, and transboundary transfer of shrimp. The crisis also involves an interaction between shrimp genetics and various human interests including protection of intellectual property. Breeders of high-quality strains generally employ (and are encouraged to employ) some form of breeder lock that generates inbreeding when broodstocks are copied . Smaller hatcheries sell these copied, inbred shrimp to farmers, who thereby increase the likelihood of losing their crops to disease. The joint behavior of breeders, hatcheries and farmers causes inbreeding to accumulate in tropical regions.

    The depressive effect of inbreeding on disease resistance is exceptionally strong in shrimp, as shown in a re-analysis of published field and experimental data. Inbreeding increases the severity and frequency of disease through a variety of mechanisms. We have relatively few, marker-based estimates of accumulated inbreeding in any non-pedigreed shrimp aquaculture system. Simulation shows, however, that locked post larvae (PLs) can be distinguished from copies in broodstocks and farm ponds, given appropriate analysis of genetic markers.

    Culture of stocks certified to be free of specified pathogens (specific pathogen free or SPF stocks) is strongly recommended and only SPF stocks can now be legally imported into most jurisdictions. These recommendations are appropriate, beneficial and necessary. But insofar as they increase the commercial value of proprietary genetic strains, such regulations may also increase the likelihood of copying, and thus inbreeding at farm level and ever-increasing susceptibility to disease and climate stress (Doyle, 2014a).

    The intellectual property value of disease-resistant strains will be extremely high and intellectual property rights are fundamental to science-based economic innovation. Breeders will, and must, continue to protect their genetic improvement programs with genetic locks, especially in regions where judicial sanctions are ineffective. The regulatory objective should be to encourage biosecurity and genetic progress while discouraging copying and consequent inbreeding.

    The current consensus that inbreeding is unimportant may therefore be out of date. Inbreeding may be amplifying the severity of diseases (including the major current threats: white spot syndrome virus or WSSV, infectious hypodermal and hematopoietic necrosis virus or IHHNV and early mortality syndrome or EMS (acute hepatopancreatic necrosis disease or AHPND). Continuing to ignore the interaction between inbreeding and disease may become a fatal error for tropical shrimp aquaculture.
  • Conference paper

    Growth and survival of nile tilapia (Oreochromis niloticus) juveniles fed diets with varying levels of irradiated chitosan 

    K Gonzales, MN Corpuz & MRR Romana-Eguia - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Chitin is a natural biopolymer and the second most abundant after cellulose. Chitosan, a derivative of chitin which is soluble in acidic aqueous media, is used in many applications like food, cosmetics, biomedical and pharmaceutical products. It is used in agriculture for enhancing growth in crops while in aquaculture, chitosan is believed to improve the immune response of fish to stress-inducing agents, thus enhancing survival and possibly growth. This preliminary study was conducted to investigate the effects of various concentrations of irradiated chitosan on the growth performance of Nile tilapia, O. niloticus. Fish was fed with a control diet and three formulated diets containing increasing levels of irradiated chitosan (10g, 20g and 50g kg-1). Juvenile O. niloticus was fed once daily for 21 days. The ration was based on 5% of the fish biomass. Tilapia fingerlings (n=30 per tank) of uniform size were randomly distributed in four experimental groups each with three replicates following a completely randomized design. Growth and food utilization parameters were measured. Specific growth rate (SGR), mean weight gain (MWG), mean length increment (MLI) and feed conversion ratio (FCR) were computed and analyzed using ANCOVA. Results from the feeding trials showed no significant difference (P>0.05) in the different performance parameters under the different fish feed treatments. MWG, MLG, SGR and FCR varied in the stocks fed different fish feed treatments but with no significant differences. The results also showed 45-62% survival ratio. These suggest that although there is no significant difference between treatments and control, irradiated chitosan-supplemented diets do not retard the growth of O. niloticus. Chitosan should be studied further to determine how it can improve the growth performance, feed utilization and immune response of Nile tilapia.
  • Conference paper

    Perceptions on the effects of maritime activities on the Philippine aquatic ecosystem 

    E Java, T Cruz & IY Hernandez - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Throughout history, humans create an impact on marine ecosystems. May it be positive or negative, such impact is long-term and shapes the overall image of the system. As humanity increases its number, so does the impact it creates. Humanity has relied on the oceans for food, recreation and for various economic opportunities. Overfishing and pollution affects the life in the seas. Advancements in fishing technology, such as tracking technologies and better transportation have reduced fish stocks significantly when matched with non-sustainable practices, such as dredging and trawling. Intentional dumping from sewages, industrial run-off and chemicals has brought about pollution in the seas. Though some pollution may be accidental, like oil spills, it still causes adverse effects to the sea. Excess nutrients coming from fertilizers and intensive farming practices have resulted to what is known as eutrophications. Lastly, changes in the marine environment have led to the introduction of invasive alien species and marine organisms, which are oftentimes difficult to eradicate. Such effects have made researchers rethink of various ways to maintain marine activities while sustaining its ecosystem.

    Through this study, the researchers determined the effects of maritime activities on the population of aquatic creatures directly from the seafarers, and found out their perspectives on how to remedy such effects and sustain the marine ecosystem.

    This research is descriptive in nature, conducted with 100 purposively selected seafarers from Manila. The participants were given a questionnaire that asked for demographics and their perceptions on the effects of maritime activities on the marine ecosystem and ways to provide solutions to minimize or avoid its negative impacts.

    Findings show equal distribution on gender, with majority at the low socioeconomic level (47%) and are Tagalog in ethnicity (56%). The seafarers believe that the maritime activities cause harm on aquatic creatures (43%), limits propagation of aquatic species (36%), makes them prone to mortality (11%) and cause pollution to the atmosphere (10%). Likewise, their perception of minimizing the consequences lies within the proper conditioning of ships and running them in good condition (57%), maintaining a clean place for the marine inhabitants (28%) and creating a good waste-renewal system (15%). The results of the paper is directed towards proper handling and maintenance of the shipping industry and strict supervision for waste management.
  • Conference paper

    Current status of aquaculture in Singapore 

    NC Heng - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Singapore is a small country state with a demographic profile of over 5 million in population. With limited land for agricultural purposes and sea space available for fish farming, Singapore depends heavily on importation of fresh seafood. Even so, Singapore has a small but thriving and increasingly important food fish farming industry which accounts for about 6% of local food fish consumption.

    The main bulk of local food fish production comes from coastal farming in floating netcages along the northern coast of Singapore. Popular species of marine food fish cultured include seabass, pompano, groupers, mullets and milkfish. There are also a few land-based fish farms culturing species like tilapia, marble goby and snakehead.

    The ornamental fish farming industry is concentrated mainly in Agrotechnology Parks and there are about 75 fish farms producing ornamental fishes with an approximate value of $76.7 million that is exported to over 80 countries.

    The Agri-Food and Veterinary Authority of Singapore (AVA) is the national authority for aquaculture development in Singapore and manages aquaculture farms through the issuance of fish farming licenses. For marine food fish farms, the farm licensee has to abide by good farm management guidelines to maintain the farm in good condition and ensure that the farm does not engage in activities that would impact the farming environment. For land-based farms, there are also guidelines that address infrastructure layout, farming system and water treatment facilities. The latter requires that sedimentation ponds, reservoir ponds/tanks, supply/drainage systems and trade effluent treatment plant are included in the farm set-up.

    There are several challenges and issues faced by the aquaculture industry in Singapore. One of these is the consistent supply of good quality fish fry as farmers have to source for fish fry from overseas sources that may not be consistent or readily available.

    Issues of fish health and farm management are other challenges faced by our fish farms. These factors affect farm productivity and the sustainability of farming operations.

    The AVA has established the Marine Aquaculture Centre (MAC) on St John's Island to address the needs of aquaculture development for Singapore through development of fish reproduction and seed production as well as large-scale fish farming technology. At present, the fish reproduction technology research work involves closing the reproductive cycles of key marine food fish species and also fry production at a commercial scale level. Closing the reproductive cycle will help to reduce the reliance on imported fry. Good quality brooders are selected, maintained and bred to produce quality fry, which would translate to better growth performance and shorter culture period. This, together with good farm management practices, will optimize the usage of fish feeds during the culture cycle.

    To fill the gap in production and supply of good quality fish seeds for local fish farms, AVA shares information on hatchery technology development with local commercial hatcheries.

    The AVA collaborates with research institutes and local fish farms in the development of vaccines to boost the survival rate of fish fry and fingerlings. This will improve survivability, thus increase the production of the farms and reduce the reliance on prophylactic drugs that may have negative consequences from prolonged use.

    The AVA also renders technical assistance to the farmers to formulate viable production plans to improve production. By leveraging on the use of technology and good farm practices, such as implementation of fish health, fish nutrition and feeding protocols, it is possible to reduce production costs and improve productivity. The introduction of the Good Aquaculture Practice scheme for food fish farming will help improve the standards of the local aquaculture industry and sustainability through responsible management practices.
  • Conference paper

    Sustainable aquaculture and resources enhancement in Indonesia 

    S Soetardjo & I Adhitya - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    With a human population of 230 million and a huge potential for marine and fisheries resources development, Indonesia promotes aquaculture as a major sector to accelerate economic growth for rural communities. There are recent initiatives to improve the country's legal framework to mitigate the adverse impacts of aquaculture and make the aquaculture more sustainable.

    The Directorate General of Aquaculture under the Ministry of Marine Affairs and Fisheries (MMAF) has the mandate to develop the aquaculture sector of Indonesia. Aquaculture has an important role in the development of its national economy and play a key role in rural development. As aquaculture production expands, there is also a growing concern over the impacts on sustainability of aquaculture and resource enhancement as well as food quality and safety requirements of fish products.

    For this reason, there is a need to improve aquaculture technology and its management system in Indonesia to address the need for eco-friendly production process and food safety concerns while maintaining the sustainability of the country's aquaculture sector. The Indonesian Fisheries Act No. 31 (2004) Amendment No. 45 (2009) mentioned that, among others, the Indonesian fisheries management strategies should include the creation job opportunities, improvement of the welfare of fishers and their communities, and ensuring the sustainability of the country's fishery resources and aquatic environment.

    The most critical factors to achieve sustainable aquaculture in Indonesia are the availability of good quality seed, good practice in grow-out systems, healthy aquaculture environment, fish health management, good-quality products, strategic marketing, and improving marketing and stock enhancement. In addition, it is also a concern that the products from aquaculture should meet the quality standard and product safety. This paper presents a review of Indonesian aquaculture in relation to sustainable practices and management schemes to preserve the aquaculture environment, food safety requirements for aquaculture products, food security and to enhance the biodiversity of fishery resources. A policy that was recently established is the development of the marine and fisheries sector based on the principles of the Blue Economy program of the Indonesian government.
  • Conference paper

    Utilization of sensors and SMS technology to remotely maintain the level of dissolved oxygen, salinity and temperature of fishponds 

    RC Munoz, RP Calderon, RC Flores, SC Masangcap & JP Angeles - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Due to the occurrence of fish kills in various fish producing areas in our country, millions of pesos and opportunities for the Filipino people had been put into waste. Bataan Peninsula State University (BPSU) collaborated with the Central Luzon Association of Small-scale Aquaculture to devise strategies to address the said problem and prevent further losses.

    More often than not, a fish kill can be attributed to the low level of dissolved oxygen (DO) in the water, decrease or increase in salinity and sudden increase in temperature, which usually occur after heavy rainfall, flooding or high tide, or high levels of ammonia due to decomposing organic matter and high temperature during summer.

    For these reasons, BPSU researchers tested the use of radio frequencies and installed sensors in different areas of the fishpond at various depths to remotely monitor the levels of DO, salinity and temperature of the water. Once these reach critical levels, the installed system which comes with a specific program, will send an alarm through radio frequencies via Short Messaging Services (SMS) technology on the cellular/mobile phone of the caretaker or the fishpond operator. Upon receiving the alarm, caretakers were able to adjust the levels of dissolved oxygen, salinity and temperature of the water by remotely switching on the air compressor or the electric water pump using their cellular/ mobile phone, thus preventing losses due to fish kills.
  • Conference paper

    Feed formulation for sustainable aquaculture 

    RM Coloso - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    As aquaculture production of tropical fish and crustacean species becomes more intensified, practical diets need to be formulated to be cost effective and environment-friendly. Ingredients should be included to satisfy the nutrient requirements of the animal, promote optimal fish growth, and boost the income of small-scale farmers and commercial producers with minimal impacts to the surrounding environment. Feed formulation for sustainable aquaculture should aim at increasing aquaculture system performance and profitability, enhancing the animals disease resistance, increasing attractability, palatability, and digestibility of practical diets, and maintaining environmental quality through sound feeding management and good aquaculture practices. More vigorous research and development efforts need to be supported to generate feed technologies that will ensure a steady and reliable supply of safe and high quality aquaculture products to the public while preserving the environment.
  • Conference paper

    Potential of cowpea (Vigna unguiculata L.) meal as an alternative protein source in diets for giant freshwater prawn (Macrobrachium rosenbergii, de Man 1879) 

    FA Aya, ML Cuvin-Aralar & RM Coloso - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    Growth trials were conducted to evaluate cowpea Vigna unguiculata (L.) meal as a potential protein source in diets for giant freshwater prawn, Macrobrachium rosenbergii (de Man 1879), reared in tank and lake-based cages. Five isonitrogenous (approximately 37% crude protein) and isocaloric diets were formulated where fish meal (FM) protein was replaced with 0%, 15%, 30%, 45% and 60% cowpea meal protein (or CP0, CP15, CP30, CP45, and CP60, respectively). Results of an 8-week tank trial showed that the final body weight (FBW), percent weight gain, specific growth rate (SGR) and survival of prawns were not significantly influenced by dietary treatments (P > 0.05), although the highest values, except for survival, were observed with CP45. In a lakebased cage trial that lasted for 16 weeks, prawns fed CP30 and CP45 had significantly higher FBW (13.1 and 14.4 g, respectively) compared to other treatment groups (P < 0.05). SGR (4.52 5.00%/ day), survival rates (53-77%), yield (98.5-116.5 g m-2) and feed conversion ratio (FCR; 2.0-2.7) were not affected by increasing levels of cowpea meal in the diets. Based on these results, cowpea meal can be considered as an alternative protein source in diets for M. rosenbergii.

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