The main objectives of this project were to study the lipid chain transfer from the egg stage through hatching and the patterns of lipid conservation or loss during starvation and feeding of larvae in order to elucidate the lipid metabolism of grouper (Phase 1); to determine the fatty acid composition of highly unsaturated fatty acid (HUFA) boosters and enriched live food organisms to enable the possibility of choosing food organisms that provide various dietary levels and ratios of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and arachidonic acid (ARA, Phase 2); and to determine the effect of Brachionus and Artemia, containing different levels and ratios of DHA:EPA:ARA, on the growth and survival of grouper larvae (Phase 3). Total lipids (TL) of samples were extracted and separated into neutral (NL) and polar lipids (PL). The samples collected in Phase 1 were floating neurula eggs, newly hatched (NHL) and unfed 4-day larvae; larvae fed with live food organisms for 25 and 35 days or starved for 3 days; and wild-sourced larvae starved for a week. In Phase 2, the samples collected were phytoplanktons, Brachionus cultured in phytoplankton for 4 days, Diaphanosoma celebensis and Pseudodiaptomus annandalei. In phase 3, larvae were fed Brachionus until day 14 and at day 25 with Artemia. E. coioides eggs contained high DHA, EPA and ARA, demonstrating their importance in larval development. Larvae primarily spent NL as energy, whereas PL was generally conserved. Wild grouper larvae had higher levels of PL than NL, whereas hatchery-sourced eggs and larvae contained higher levels of NL than PL. Based on the lipid content of wild larvae, high phospholipid diets were essential for larvae survival and normal development. A variety of products were effective in enriching the HUFA content (particularly ratios of DHA, EPA and ARA) of live food organisms. HUFA-enriched live food organisms enhanced the growth, survival and pigmentation in grouper larvae.

This study was undertaken to investigate the occurrence of some digestive enzymes in the gastrointestinal tract during early development in the grouper. This work was conducted to provide information on formulating an appropriate feeding scheme and an artificial diet for the early development of the grouper, Epinephelus coioides. Larvae of E. coioides were reared in 5 tonne rectangular concrete tanks. The digestive enzymes localized were acid phosphatase (ACP), alkaline phosphatase (ALP), nonspecific esterase (NSE), aminopeptidase (AMP), trypsin (TRP), maltase (MAL) and lipase (LIP). Weak enzyme activity occurred during the yolk sac stage. High AMP activity started at day 14 prior to Artemia feeding at day 16. Fluctuations in TRP activity might be related to stomach formation. Occurrence of MAL during early development demonstrated a capacity to digest carbohydrates. An increase in LIP activity coincided with the occurrence of gastric glands. Insignificant changes in digestive enzymes were observed in the metamorphosing grouper larvae from day 40 to 60.

These series of experiments were conducted to determine the effects of density (200, 400, 800 and 1600 eggs/litre), salinity (8, 16, 24, 32 and 40 ppt), aeration (0, 0.62, 1.25, 2.50 and 3.75 ml/min/litre) and light intensity (0, 120, 230, 500 and 700 lx) on the survival of fertilized eggs and early stage larvae of Epinephelus coioides. Under statice incubation conditions, the highest egg viability, hatching rate and percentage of normal larvae were obtained at a stocking density of 400 eggs/litre with moderate aeration (100 ml/min) and salinity of 32-42 ppt. Gentle aeration at 0.62 to 1.25 ml/min/litre, rearing water of 16 to 24 ppt and a light intensity of 500 to 700 lx maximized the survival of early stage E. coioides larvae in the hatchery.

The extensive Philippine coastline of more than 22,540 k m provides the natural habitat of a variety of flora and fauna that make the Philippine archipelago one of the centers of marine biodiversity in the world. Resource-use conflicts, overexploitation, and the pressure to feed the teeming population in many fishing communities have however degraded these habitats, seriously threatening marine biodiversity that supports the biological productivity of the country's coastal fishery. Encouraged by recent enabling national legislation (e.g., the Local Government Code of 1991, the National Integrated Protected Areas System Act of 1992, the Philippine Fisheries Code of 1998), grassroots advocacy in many municipalities has grown to address this threat, resulting in the establishment of marine protected areas (MPAs), particularly in coral reef management. The over 550 MPA s catalogued in the Philippines to date were established primarily to enhance local fishery yields for artisanal fishers and secondarily to protect coastal habitats for biodiversity conservation and multiple economic uses. Enforcement in a majority of these MPAs is a serious problem however. Many government and donor-assisted projects, such as the UNESCO Biosphere Reserves in Puerto Galera and Palawan, have promoted integrated management of both upland and coastal habitats, but these too suffer from persistent conflicts in multiple resource-use and the lack of sustained enforcement by stakeholders. Our recent experience in Malalison Island, central Philippines describes the efforts of empowering the island fishers themselves to be effective and responsible managers of their marine resources. Grassroots empowerment required organizing the island fisherfolks in 1991 into a working association to promote collective action on a number of local reef fishery management initiatives, particularly the establishment of exclusive-use rights over the island's reef fishing grounds, which entailed influencing the municipal government and neighboring villages. Specific interventions that followed were highlighted by the establishment of a no-take marine reserve and the deployment of concrete artificial habitats in one of their fishing grounds in Gui-ob reef in 1995-1996. Indicators of equity, efficiency, and sustainability suggest that island fisherfolks have gained greater control over their reef fishery resources, allocated their fair share of access rights, and influenced the formulation of fishery co-management policies through direct participation. In the process of empowerment, the island community leaders and many members have become bold and confident in publicly articulating their vision of sustaining harvest from their reef fisheries, a trait that they have not openly displayed prior to 1991. The experience in Malalison Island has demonstrated that fishery co-management, as exemplified by sustained protection of a no-take marine reserve, can be an achievable goal in the Philippines. It may serve as a valuable model to be followed by other coastal fishing communities in Southeast Asia and elsewhere.

Declared a Man and Biosphere Reserve in 1991, the Palawan Biosphere Reserve in the Philippines is a biologically diverse province and home to a number of Indigenous Peoples particularly the Pala’wan, Tagbanua and Batak tribes. These IPs are dependent on their traditional wildlife hunting and gathering practices for food. The province-wide federation of the Indigenous Peoples, the Nagkakaisang Mga Tribung Palawan (NATRIPAL) or the United Tribes of Palawan, is undertaking projects in the area of education, health, organizing, advocacy and livelihood programs towards building a better future for the tribal peoples. A key initiative is the development for the mainstream market of specialty products such as the wild honey traditionally gathered for household consumption and at a limited scale for the local market. The opportunities, challenges and strategies in the development of this specialty product based on customary knowledge and practices of gathering enhanced by mainstream technology and enterprise management scheme(s) is discussed in the context of sustaining cultural and biological diversity of the indigenous peoples of Palawan Biosphere Reserve.

The milkfish, Chanos chanos, is an important aquaculture resource in Southeast Asia. Using NGS data, 72 microsatellite markers were developed. PCR product confirmation using agarose gel electrophoresis allowed the identification of 24 utilizable markers. Milkfish samples (n = 48) from a hatchery stock in Palawan, Philippines were analyzed for genetic variability at the aforementioned 24 loci. Consequently, nine of these microsatellite loci were noted to have high success rate in amplification, exhibited polymorphism with 19 maximum number of alleles and no null alleles. These are the first microsatellite markers to be developed and characterized for C. chanos that will efficiently enable genetic stock delineation and monitoring as well as marker-aided genetic improvement research.

This study examined the diet composition, feeding preferences, and mouth morphology of the silver therapon (Leiopotherapon plumbeus, Kner 1864) larvae under captive conditions. Larvae were reared in outdoor tanks (4 m³) with natural food grown 2 weeks prior to start of larval rearing. Food preference was measured by the Chesson's electivity index (α_i). Gut content analysis of larvae sampled between 5 and 25 days after hatching (DAH) showed the dominance in the diet by zooplankton, mainly copepod nauplii, cladocerans and insect larvae. Small fish larvae (5–9 DAH; 3.32–6.29 mm standard length) preferred cladocerans, ciliates and copepod nauplii; whereas older larvae (12–25 DAH; 5.45–19.26 mm standard length) preferred insect larvae over cladocerans and adult insects. The mouth gape size at 5 DAH was 359 μm and increased to 3.75 mm at 40 DAH when body size grew at an average rate of 0.59 mm d⁻¹. The standard length (SL) of L. plumbeus larvae was strongly associated with mouth size (r² = 0.98, P < 0.05), indicating a progressive increase of ingested prey size of the fish larvae. These results clarified the early life feeding ecology of this species, which is essential in developing effective hatchery techniques.

A 56-day feeding trial was conducted to determine the effects of supplementing diets of juvenile Japanese flounder, Paralichthys olivaceus, with Eucheuma denticulatum (EDP). Isonitrogenous and isolipidic test diets were prepared using a fishmeal-based positive control diet (PC) and a fishmeal-soy protein concentrate negative control diet (NC) supplemented with 3 (D3%), 6 (D6%) and 9% (D9%) EDP. The test diets were assigned to tanks (12 fish tank⁻¹, initial mean body weight of 0.42 ± 0.01 g) in triplicates. Results of the feeding trial indicated that growth rates and feed efficiency significantly improved (P < 0.05) when 3% EDP was supplemented in the diets. However, there was a significant reduction (P < 0.05) of growth and feed efficiency in fish fed diets with higher supplementation levels. Protein, lipid, dry matter and ash contents of carcass and their corresponding nutrient retention values were not markedly altered in all dietary treatments. Fish fed diets supplemented with EDP exhibited higher (P < 0.05) omega-3 polyunsaturated fatty acid accumulation in dorsal muscle when compared with those of fish fed NC. Blood chemical parameters showed significant differences (P < 0.05) in total cholesterol and triglyceride levels. These results suggest that EDP can be efficiently utilized by Japanese flounder and can promote best growth and feed utilization at a level of 3%.

Effects of supplementation of diets with freeze-dried Chaetoceros calcitrans to control Vibrio harveyi infection are evaluated through immune responses, and disease resistance of juvenile Penaeus monodon. Total lipid and fatty acid profile of Chaetoceros calcitrans is also analyzed. A challenge infection with 10⁷ cfu/mL concentration of Vibrio harveyi is intramuscularly injected to juvenile Penaeus monodon after 45 days of feeding of diets supplemented with 15 g/kg and 30 g/kg dried Chaetoceros calcitrans. The use of dried Chaetoceros calcitrans is compared with that of ß-1,3 glucan Curdlan, a commercial immune enhancer. Incorporation of 30 g/kg Chaetoceros calcitrans in the diet enhances the immune system of shrimp as effected by high prophenoloxidase activity and plasma protein concentration and is better compared to the commercially available Curdlan. Chaetoceros calcitrans also contains polyunsaturated fatty acids (PUFAs) such as linolenic acid and eicosapentanoic acid (EPA) which are responsible for its antibacterial action against Vibrio harveyi. All these biological activities of Chaetoceros calcitrans add up to increase resistance of the juvenile Penaeus monodon to vibriosis as shown by its high survival rate from the challenge infection with Vibrio harveyi. Therefore, it is worthwhile to use Chaetoceros calcitrans as supplementary feed. Its effect in increasing the immune competence coupled with its antibacterial action, make the shrimp resistant to luminous vibriosis that continues to affect the industry, thereby augmenting aquaculture production.

Numerous studies have been conducted on ballast water species composition and diversity in other countries but not in the Philippines. Thus, this study aimed to provide baseline information on the plankton diversity in ballast water of the inter-island passenger-cargo vessel calling the ports of Iloilo-Bacolod-Manila Cagayan de Oro, Philippines and vice-versa. Specifically, this study aimed to determine the presence of phytoplankton and zooplankton diversity and species density of this plankton measured in cells/ml using the haemacytometer technique. Composite sampling was employed having one liter of ballast water used per ballast tank. A total number of 15 genera of phytoplankton (diatom) and one genus of zooplankton were recorded. Chroococcus, Nannochloris and Protococcus had the highest cells/ml while Ankistrodesmus, Micromonas and Synedra had the lowest cells/ml. The most common phytoplankton observed in ballast tanks were Nannochloris and Protococcus. Neocalanus (copepod) was present in all ballast tanks except in ballast tank 1 (fore-peak). The phytoplankton and zooplankton composition was found to be non-invasive in nature showing its ubiquity in the marine environment. This study provides an initial assessment or preliminary list of phytoplankton and zooplankton diversity from the ballast water of a passenger-cargo vessel calling the Philippine ports.