This study was conducted to investigate the sea cucumber fishery and compare populations between exploited and unexploited sites. Three islands were selected, the Arrecife Island as the unexploited site and the Johnson and Green Islands representing the exploited sites. In each site, sea cucumber species richness, diversity and densities were assessed by laying as much as 15 transects (50 m × 5 m) per habitat in each island. Differences in species richness, diversity and relative densities across sites and habitats were tested using a Two-way Analysis of Variance (ANOVA) and Tukey test for post hoc comparisons. An interview with gatherers, key informants and focus group discussions were also conducted to gather information on the sea cucumber fishery and its management. Results showed that the unexploited site had a higher species richness (14 vs. 7 and 7). Relative density of species was also higher in the unexploited site at 1245 ind ha^-1 while it was only 78 and 39 ind ha^-1 in exploited sites (p < 0.05). Interviews and a focus group discussion revealed that national regulations on permit system and size limits were not enforced at the local level and that gatherers had low levels of awareness regarding regulations on sea cucumber harvest. Current management measures appear to be ineffective and insufficient, leaving the sea cucumbers in areas open to exploitation at risk of depletion. Given that sea cucumbers provide substantial income to local communities, the depletion of this resource could compromise the livelihood of people in island communities that rely heavily on marine resources for living. Thus, this study highlights the need to review national policies on sea cucumber fishery and place the management at the local level.

Marine microbes encounter a myriad of biotic and abiotic factors that can impact fitness by limiting their range and capacity to move between habitats. This is especially true for environmentally transmitted bacteria that cycle between their hosts and the surrounding habitat. As geologic history, biogeography, and other factors such as water temperature, salinity, and physical barriers can inhibit bacterial movement to novel environments, we chose to examine the genetic architecture of Euprymna albatrossae (Mollusca: Cephalopoda) and their Vibrio fischeri symbionts in the Philippine archipelago using a combined phylogeographic approach. Eleven separate sites in the Philippine islands were examined using haplotype estimates that were examined via nested clade analysis to determine the relationship between E. albatrossae and V. fischeri populations and their geographic location. Identical analyses of molecular variance (AMOVA) were used to estimate variation within and between populations for host and symbiont genetic data. Host animals demonstrated a significant amount of variation within island groups, while symbiont variation was found within individual populations. Nested clade phylogenetic analysis revealed that hosts and symbionts may have colonized this area at different times, with a sudden change in habitat. Additionally, host data indicate restricted gene flow, whereas symbionts show range expansion, followed by periodic restriction to genetic flow. These differences between host and symbiont networks indicate that factors “outside the squid” influence distribution of Philippine V. fischeri. Our results shed light on how geography and changing environmental factors can impact marine symbiotic associations at both local and global scales.

Recent improvements in hatchery production technology for high-value marine finfish species such as groupers have led to an increased interest in setting up hatcheries to produce fingerlings for aquaculture. Small-scale hatcheries make this technology available to poor people in developing countries. Capital costs for small-scale hatcheries are relatively low, and the profitability of these ventures ensures rapid payback of capital investment. This guide provides an outline of the requirements to establish a small-scale marine finfish hatchery, particularly the economic aspects. It is intended to provide sufficient information for potential investors to decide whether investment in such ventures is appropriate for them. The guide provides some basic technical information in order to give an indication of the level of technical expertise necessary to operate a small-scale marine finfish hatchery. However, it is not intended as a detailed technical guide to the operation of small-scale hatcheries. Additional resources, such as training courses in marine finfish hatchery production, are available and these are listed in this document. Development of small-scale hatcheries may be more appropriate where there are existing marine hatchery operations, e.g. for shrimp or milkfish. By definition, small-scale hatcheries do not have broodstock facilities, so a supply of fertilised eggs (usually from a larger hatchery) is essential. Access to fertilised eggs and experienced hatchery staff will limit the application of small-scale hatchery technology. Despite this, there is considerable potential for this technology to be widely adopted. This guide has been written by a team of experts in marine finfish aquaculture who have been involved in a multinational collaborative research project since 1999.

This study evaluated the effects of dietary fermented tuna by‐product meal (FTBM) in juvenile olive flounder, Paralichthys olivaceus. Five diets were formulated to replace fishmeal (FM) with FTBM at 0% (FTBM₀), 12.5% (FTBM_12.5), 25.0% (FTBM₂₅), 37.5% (FTBM_37.5), or 50% (FTBM₅₀). After 8 wk, weight gain, specific growth rate, and feed efficiency of fish fed FTBM₀ and FTBM_12.5 diets were significantly higher than fish fed the other diets (P < 0.05). Also, mean cumulative survival rates (%) of fish fed the FTBM₀ and FTBM_12.5 diets were significantly higher than those fed FTBM₅₀ diet at Day 9 postchallenge with Edwardsiella tarda (P < 0.05). Protein efficiency ratio of fish fed FTBM₀ and FTBM_12.5 diets was significantly higher (P < 0.05) than fish fed diets FTBM_37.5 and FTBM₅₀. Broken‐line regression analysis of weight gain showed an optimal FM replacement level of 10.65% with FTBM. Therefore, the optimal dietary inclusion of FTBM in juvenile olive flounder diets could be greater than 10.65% but less than 12.5% without any adverse physiological effects on fish health.

The silver therapon, Leiopotherapon plumbeus (Kner, 1864), is an endemic and economically important freshwater food fish in the Philippines. The natural populations of this species have been declining during the past years, mainly due to intense fishing pressure, habitat degradation, and introduction of invasive alien species. At present, it is considered a target species for domestication and conservation efforts. Despite several attempts of artificial reproduction and larval rearing, little is known on larval and early juvenile development of silver therapon. The presently reported study was therefore intended to fill this gap in the knowledge by determining the growth and describing body proportions, pigmentation, and fin formation of this fish. Newly hatched larvae were reared in mesocosm tanks at a mean temperature of 29.5°C. Larvae up to 30 days after hatching were sampled at irregular intervals and preserved in 5% buffered formalin. Early development stages for 245 preserved specimens were described in detail with reference to changes in morphology, growth and body proportions, pigmentation, and fin formation. Five developmental stages of silver therapon were identified: yolk sac larva (1.88 mm TL), preflexion (2.51 mm TL), notochord flexion (4.50-8.27 mm TL), postflexion larva (6.90-12.21 mm TL), and early juvenile (>13.40 mm TL). Growth was isometric for eye diameter and gape size whereas positive allometry was observed for body depth, head length, and preanal length. Some body proportions showed abrupt changes from preflexion to postflexion larvae before it stabilized during the early juvenile stage. Pigmentation in the form of stellate and punctate melanophores increased with developmental stage, with larvae becoming heavily pigmented from postflexion to early juvenile stage. These morphological changes, together with the full complement of fin rays and squamation observed in specimens larger than 13.4 mm TL, suggest the attainment of the juvenile stage of this species. These morphological changes may explain the food and feeding habits during the early life stages of silver therapon which is critical to their survival and recruitment in the wild and in a mesocosm hatchery environment.

The optimum culture conditions of the local strain Chaetoceros calcitrans were determined to improve biomass and reduce cost of production. Under outdoor culture conditions, higher cell density was attained when the cultures were enriched with Tungkang Marine Research Laboratory (TMRL) medium composed of cheap technical grade reagents and cultured at 25 g L⁻¹ salinity. The cultures were lighted with two 40 W cool-white GE fluorescent tubes (24–35 μmol photon m⁻² s⁻¹). Using semi-continuous culture system under established optimum culture conditions, C. calcitrans can be re-cultured thrice and concentrated at each culture cycle using electrolytic flocculation method to produce 4.6 kg m⁻³ of diatom paste. The viability of concentrated C. calcitrans after 3 months of storage was comparable to live diatom cells. Simple preservation technique by low-temperature storage is convenient for storing algal concentrates for use as starter cultures and for feeding invertebrates. The paste costs USD 8.24 kg⁻¹ inclusive of the assets and flocculation materials for culturing and harvesting the diatom, respectively. This study established the suitable conditions for mass culture of C. calcitrans and produced concentrated diatoms in paste form that is readily available for aquaculture hatcheries at a lower cost.

The increasing global demand for mud crabs (genus Scylla) and threats to the wild populations highlight the urgency of fully rearing them in captivity. Despite considerable progress in mud crab production, most crab farms still rely heavily on wild-caught crablets and juveniles while the low and inconsistent success rates of larviculture remain as the main bottleneck impeding the development of mud crab aquaculture. Over the years, numerous studies have been conducted to determine the optimum larval rearing parameters, the ontogenic changes in digestive function and feeding behaviour, and the diets for different larval stages. These data, however, are dispersed and not summarised to inform culture practices. This review provides an update on the current progresses and to pinpoint the gaps in knowledge regarding mud crab larval rearing. We include all four mud crab species under the genus Scylla, i.e. Scylla serrata, Scylla olivacea, Scylla tranquebarica and Scylla paramamosain. Knowledge compiled in this review serves as an important guideline for prospective mud crab larviculture. Future research should gear towards filling in the gaps in our knowledge to advance mud crab larval rearing, thus fully incorporating mud crab into the aquaculture sector.

The Second International Conference on the Culture of Penaeid Prawns and Shrimps (SICCPPS) was convened in Iloilo City by the Southeast Asian Fisheries Development Center (SEAFDEC) on May 14-17 1996 to bring together scientists, researchers and industry practitioners to discuss developments and constraints in shrimp culture. Two simultaneous workshops were held after the presentation of scientific papers: the Workshop on Seed Production and the Workshop on Pond Grow-out Culture of Shrimp.

Findings of previous studies revealed that regardless of the objective, age does affect the information-seeking behavior of an individual. Likewise, this study found the same results. Although all of the younger Filipino aquaculture researchers preferred the Internet to begin their search process, it was found that they were more frequent library users, and more reliant on librarians than their older counterparts. Likewise, they preferred the combination of print and electronic formats when reading. Thus, they would print and save the retrieved electronic copy of information at least very often. The study is a valuable addition to the information-seeking behavior studies on Filipinos, and the first to tackle the effects of age on the information-seeking behavior of Filipino aquaculture researchers.

Mangrove rehabilitation has a long history in the Philippines dating back to the 1930s. The standard practice is the planting of bakhaw Rhizophora propagules by paid community members (or volunteers) in seafront sites selected during spring low tides. In 2009, the Community-based Mangrove Rehabilitation Project (CMRP) of the Zoological Society of London was established to: (a) rehabilitate abandoned government-leased fi shponds into healthy mangroves; (b) increase coastal protection, food resources, and livelihood income through sustainable management of mangroves; and (c) re-establish the legally mandated mangrove ‘greenbelt’ along the coast. Over four years, the CMRP has planted the following in various partner sites in Panay and Guimaras: (a) 58,000 seeds or wildings bagged in nurseries by 3,000 participants, and (b) 99,000 seedlings/wildings outplanted by 4,000 planters in ~20 ha of greenbelts and abandoned ponds. The species are mainly bungalon/piapi Avicennia marina, pagatpat Sonneratia alba, and to a lesser extent, bakhaw Rhizophora. The planters include high school/college students and teachers, members of people’s organizations, barangay and municipal government employees, BFAR and DENR staff , and civil society organizations. The extensive CMRP trials have yielded signifi cant learnings, many of them paradigm shifts from present protocols, as included in the 20 Golden Rules of Mangrove Rehabilitation. A manual that documents these learnings with concrete examples based on CMRP monitoring of fi xed quadrats and other standardized protocols, is currently in press. Some of these protocols are the following: (a) planting site: shift from seafront sites to abandoned ponds (whenever possible); (b) time of site selection: during (low tide of) Neap Tide rather than Spring Tide; (c) species selection for seafront sites: the ecologically correct bungalon/piapi and pagatpat, rather than the easy-to-plant but unsuitable bakhaw; (d) sources of planting materials: use of available wildings is harvesting nature’s excess (equivalent to withdrawing from ‘seedling banks’), which also saves time; (e) labor: “No Pay” planting is based on the premise that labor contributed by the community provides the basis for ownership, thereby obligating them to nurture the plants to maturity and validating their role as de facto managers of mangrove resources. Similar mangrove initiatives have been observed elsewhere in Southeast Asia, as follows: (a) barriers/breakwater in MaIaysia, Vietnam, and Thailand; (b) use of wildings in Malaysia; and (c) mangrove ecoparks/reserves in Singapore, Thailand, Vietnam and Brunei.