Southeast Asian Fisheries Development Center
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The aquaculture supply chain in the time of covid-19 pandemic: Vulnerability, resilience, solutions and priorities at the global scale
No full textThe COVID-19 global pandemic has had severe, unpredictable and synchronous impacts on all levels of perishable food supply chains (PFSC), across multiple sectors and spatial scales. Aquaculture plays a vital and rapidly expanding role in food security, in some cases overtaking wild caught fisheries in the production of high-quality animal protein in this PFSC. We performed a rapid global assessment to evaluate the effects of the COVID-19 pandemic and related emerging control measures on the aquaculture supply chain. Socio-economic effects of the pandemic were analysed by surveying the perceptions of stakeholders, who were asked to describe potential supply-side disruption, vulnerabilities and resilience patterns along the production pipeline with four main supply chain components: a) hatchery, b) production/processing, c) distribution/logistics and d) market. We also assessed different farming strategies, comparing land- vs. sea-based systems; extensive vs. intensive methods; and with and without integrated multi-trophic aquaculture, IMTA. In addition to evaluating levels and sources of economic distress, interviewees were asked to identify mitigation solutions adopted at local / internal (i.e., farm-site) scales, and to express their preference on national / external scale mitigation measures among a set of a priori options. Survey responses identified the potential causes of disruption, ripple effects, sources of food insecurity, and socio-economic conflicts. They also pointed to various levels of mitigation strategies. The collated evidence represents a first baseline useful to address future disaster-driven responses, to reinforce the resilience of the sector and to facilitate the design reconstruction plans and mitigation measures, such as financial aid strategies
Whole-genome sequencing for identification of bacterial isolates affecting local penaeid shrimp farms: A national survey for the Philippines
No full textThe shrimp aquaculture industry is a major economic player in the food and livelihood sectors, both globally and in the Philippines. The development of industrialized shrimp farming methods has led to a rapid increase in cultured shrimp production since the 1980s, but the industry has also faced challenges from the introduction of opportunistic pathogens. These pose severe limitations in the success of shrimp culture in both hatcheries and grow-out ponds. We extracted genomic DNA from 423 bacterial isolates from shrimp disease outbreaks in local aquaculture farms throughout the Philippines and subjected them to Illumina paired-end whole-genome sequencing at 50–100-fold coverage. Reads were assembled using a de novo approach, and average nucleotide identity measurements were used to establish the identity of the isolates. Outbreak types encountered during the time of sampling include acute hepatopancreatic necrosis disease (AHPND), luminescent vibriosis, white spot disease, and outbreaks of unknown etiology. In both outbreak and non-outbreak sites, members of the genus Vibrio, particularly Vibrio parahaemolyticus, were observed to be the most abundant. The whole-genome sequence data obtained will aid in the design and implementation of novel shrimp bacterial disease outbreak management and control programs.The authors acknowledge the Aquaculture Department of the Southeast Asian Fisheries Development Center (SEAFDEC), the Negros Prawn Growers’ Cooperative, the Bureau of Fisheries and Aquatic Resources, and the many fish pond operators throughout the country and various research assistants employed by the program for help in the collection of bacterial isolates used in this study; and the UP Philippine Genome Center – DNA Sequencing Core Facility (PGC-DSCF) and Core Facility for Bioinformatics (PGC-CFB) for providing sequencing and bioinformatics analysis services, and Ms Krizelle Alcantara for her assistance in the preparation of this manuscript. This work was made possible through the funding support of the Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development of the Department of Science and Technology (PCAARRD-DOST) for the project “Shrimp Pathogenomics Towards a Competitive and Sustainable Shrimp Industry” under the program “Development of Diagnostic Tools Through Genomics and Establishment of the Philippine Aquatic Pathogen Database Resource for the Philippine Aquaculture Industry”. The authors are grateful for the help provided by Drs Adelle Calpe and Dalisay Fernandez of PCAARRD-DOST in the implementation of the program
The influence of monosex rearing on gonad maturation and reproductive behavior of Indian white prawn, Penaeus indicus broodstock
No full textMonosex culture was proven to be an effective rearing method for grow-out, but in a closed-cycle hatchery, males and females are usually reared communally in tanks until maturation. This study determined the effect of communal rearing (CR) and separate rearing (SR) on male and female Penaeus indicus broodstock gonad maturation. This study also evaluated the influence of the rearing method on reproductive behavior and mating success. The results showed that CR female broodstock had higher maturation rates at 77.78 ± 5.31% (p = 0.061) and a shorter latency period at 6.71 ± 2.54% than SR females (p = 0.211), but the differences were not statistically significant. Similarly, maturation rates for both male groups were 40.62 ± 3.12% and were not significantly different (p = 1.00). The interspermatophore period (p = 0.044), spermatophore weight (p = 0.878), count (p = 0.780), viability (p = 0.257), and percent abnormality (p = 0.257) did not vary between males. In terms of the effect of rearing method on reproductive behavior, males from the SR group initiated more chase (p = 0.018) and fight with other males (p = 0.022) than CR males did, and the differences were significant. SR males also touched the discarded molt (p = 0.167) and advanced to the probe position (p = 0.525) more times than CR males, but the differences were not significant. The sum of all the reproductive behaviors was also significantly higher in the SR (54.00 ± 1.20) than in the CR (24.20 ± 0.86) groups (p = 0.017). Initial results showed that successful mating in the SR (80%) was higher than that recorded in the CR group (20%). These findings suggest that monosex rearing of male and female P. indicus will not negatively affect gonad maturation and will enable sex-specific nutritional manipulations, which can even possibly promote higher mating success.This study was funded by the Department of Science and Technology-Accelerated Science and Technology Human Resource Development Program, Student Research Support Fund and SEAFDEC/AQD (FD-02-C0219T)
Communicating the value of international grey literature: The Aquatic Sciences and Fisheries Abstracts experience
No full textIn collaboration with its partners, ASFA has worked across multiple platforms to raise awareness and understanding of the effective promotion of grey literature to the managers and users of this valuable information source. This chapter presents the outreach activities, promotional materials, and training sessions that have been successfully implemented to achieve this aim, and reflects on both successes and areas where improvements are yet to be made
Innofloc: Innovative biofloc technology for the nursery production of shrimp, Litopenaeus vannamei in tanks
No full textNursery systems are valuable production tools in shrimp aquaculture and are effective biosecurity facilities for the high-density culture of shrimp postlarvae (PL), resulting in healthy and uniform-sized juveniles. The nursery production of shrimp is usually carried out in small ponds; however, the use of small and circular tanks with plastic liners is gaining popularity. From an industry standpoint, there is a need to assess how nursery systems can improve the productivity of the shrimp production cycle. Hence, the use of small circular tanks coupled with the incorporation of biofloc technology was assessed in terms of its viability during the nursery production of the Pacific whiteleg shrimp, Litopenaeus vannamei. A 450m2 plastic-lined circular tank was installed and prepared for the stocking of L. vannamei postlarvae (PLs) at a density of 500 PLs per m2. Biofloc was produced and maintained throughout the nursery phase by adding brown sugar as a carbon source at carbon to nitrogen (C:N) ratio of 10. Daily monitoring of the various water quality parameters was carried out, while presumptive Vibrios were enumerated weekly. The shrimp juveniles were sampled for their body weight on the 14th day post-stocking and weekly until harvest on the 30th day of culture. The different water quality parameters were within optimum levels required for shrimp growth. Presumptive Vibrios were dominated by the yellow colonies. The shrimp attained 100% survival with an average body weight of 1.26 g and a feed conversion ratio (FCR) of 0.43 at the end of the nursery production phase. Our results indicate that the use of small circular tanks with biofloc during the nursery production phase of whiteleg shrimp is feasible and can be incorporated during the grow-out culture for improved and continuous production of this shrimp species.Department of Science and Technology (DOST) through the Science for Change Program (SC4P) – Collaborative Research and Development to Leverage Philippine Economy (CRADLE) for the funding and the Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (PCAARRD) for assisting and monitoring the project activities
Biofloc-based nursery production system: Heeding the call towards a sustainable shrimp culture industry in the Philippines
No full textThe increasing global population resulted in intense pressure on the food production sectors to meet the rise in food demand. The aquaculture industry, which is one of the major food production sectors, provides opportunities in addressing issues on malnutrition and poverty alleviation. Shrimp farming is an important sub-sector in aquaculture because shrimp are not only good sources of food, but they contribute to the national economy through export revenues. This resulted in the rapid intensification of shrimp aquaculture, which created negative issues on sustainability and environmental impacts. Hence, this necessitates an urgent need to develop aquaculture production systems that yield high productivity and profitability yet possess a low carbon footprint. Biofloc technology (BFT) fit into these criteria as this technology permits intensive culture of aquatic species, less use of resources, and improved water quality as a consequence of the production and activity of beneficial microbial biomass, which, at the same time, can be utilized as a source of feed for the growing shrimp. BFT has been shown to be successful on a commercial scale during shrimp grow-out, and recent studies have shown that this technology can be further refined and optimized for the production of shrimp during the nursery phase. This review, therefore, highlights the basics of BFT and how this technology is being optimized in the production of shrimp during the nursery phase. More specifically, this discusses the benefits of this approach in ensuring a productive yet sustainable way of producing shrimp in the context of Philippine aquaculture.This research study is part of the project, “Bioflocbased Nursery Tank Production of Shrimp for Quality and Sustainable Supply of Aquaculture Products in the New Normal” funded by the Department of Science and Technology (DOST) through the Science for Change Program (S4CP) – Collaborative Research and Development to Leverage Philippine Economy (CRADLE) and monitored by DOST – Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (PCAARRD) with Project Number 8444 awarded to CMA Caipang. The authors gratefully acknowledge the support provided by the University of San Agustin and Marmi Agricultural Corporation
Comparison of commercial Spirulina, live Navicula sp. and Chaetoceros calcitrans concentrate as settlement cues for sandfish, Holothuria scabra
No full textThe settlement of sea cucumbers is a crucial phase of larval development because the highest mortality occurs at this stage. Substrates and cues are commonly used to induce larval settlement. Commercial algae and live benthic diatoms are the most common settlement cues being used. The present study evaluated Chaetoceros calcitrans concentrate as a potential settlement cue for H. scabra. Three settlement cues, replicated three times, were compared: commercial ‘Spirulina’, live benthic diatom Navicula sp., and C. calcitrans concentrate. Settlement substrates without cue served as control. ‘Spirulina’ paste and C. calcitrans concentrate were painted onto the settlement substrates, while settlement substrates were introduced into a Navicula sp. culture tank to enable attachment of the benthic diatom. Faster and higher settlement was observed in the treatment with ‘Spirulina’ paste as cue at 89% five days post introduction of substrates, compared with live Navicula sp. and C. calcitrans concentrate at 74% and 63% seven days post introduction, respectively. For the control, only 25% of the larvae have settled eight days after introduction to the substrates. ‘Spirulina’ paste and live Navicula sp. showed better settlement rates, but these were not significantly different compared with C. calcitrans concentrate. Therefore, C. calcitrans concentrate can be a potential settlement cue for H. scabra larvae.This study is part of the MSc thesis submitted to the College of Fisheries and Ocean Sciences, University of the Philippines Visayas and was conducted at the Aquaculture Department, Southeast Asian Fisheries Development Center (SEAFDEC/AQD) under the study code 5209-T-RD-BR0114. The authors greatly appreciate SEAFDEC/AQD for the use of facilities; the SEAFDEC/AQD Sea Cucumber Hatchery for the sea cucumber larvae; the SEAFDEC/AQD Natural Food Laboratory for the Navicula sp. and Chaetoceros calcitrans concentrate; Mr. Neil Tibubos, Mr. Jesus Rodriguez, Jr. and Mr. Romeo Tibudan for the assistance during the conduct of the experiment; and the anonymous reviewers for patiently reviewing the manuscript
Effect of water mass mixing on phytoplankton dynamics in the scallop culture areas off Okhotsk Sea: A microcosm experiment
No full textThe nearshore (Soya Warm Water (SWW)) and offshore (Intermediate Cold Water (ICW) and Okhostk Sea Low Salinity Water (OSLSW)) waters in the Okhotsk Sea differ substantially in their physico-chemical characteristics. Thus, the extent to which water mass mixing impacts phytoplankton dynamics in the Japanese scallop Patinopecten yessoensis culture areas needs to be assessed to properly manage scallop stocks. This study examined the phytoplankton dynamics in nearshore (SWW) and offshore (ICW and OSLSW) waters and phytoplankton response to water mass mixing (SWW + ICW, OSLSW + ICW) for 5 days in spring (2007) and summer (2007–2009) microcosm experiments. Increased chlorophyll a concentration in ICW was observed due to higher nutrients available for phytoplankton uptake than in OSLSW and SWW at the start of each microcosm experiment. In comparison to spring microcosm, mixing of SWW + ICW promoted higher chlorophyll a concentration and faster Si(OH)4 utilization than in OSLSW + ICW in summer. In addition, the size structure of chlorophyll a differed from micro-size (>) in SWW + ICW to nano-size (<) chlorophyll a in OSLSW + ICW. Suspended particulate organic matter (SPOM) ratios were positively correlated with chlorophyll a in both mixed microcosms whereas SPOM isotopic ratios were inversely related to nitrate concentration in SWW + ICW, except in spring. This suggests that stable isotopes can be used in predicting phytoplankton biomass and nutrient utilization. In comparison to microcosm experiments, nearshore water column structure suggests vertical water mixing in summer to autumn when phytoplankton biomass and micro-size fraction were at maximum. Taken together, the advance of nutrient-rich ICW to nutrient-poor nearshore areas in the Okhotsk Sea resulted in increased chlorophyll a biomass and dominance of micro-size phytoplankton in summer, potentially enhancing nutrient and food supply to bottom-cultured scallops as suggested by both microcosm experiments and field observations.This study was supported by research grants from the Hokusui Society Foundation to I. Kudo, and the Ministry of Education, Culture, Sports, Science and Technology, Japan to F.A. Aya
Economic performance and roles of local communities in the adoption of multi-species aquaculture
Get PDFEvaluation of seafloor environmental characteristics of harvesting ground of a kelp Saccharina longissima using GIS in the Pacific coastal area of eastern Hokkaido, Japan
No full textThe characteristics of the seafloor environment of the harvesting grounds of the kelp, Saccharina longissima, were evaluated by spatial analysis using a geographic information system (GIS) in the Pacific coastal area of eastern Hokkaido. The kelp harvesting grounds were formed in water depths ranging from 1.2 m to 9.6 m, slopes ranging from 0° to 16.3°, bottom substrate (coarseness score) ranging from 1.82 to 3.00, bottom current velocities ranging from 0.7 cm/s to 116.4 cm/s, and a maximum slope of 37.6°. These values include the viable environmental conditions for the kelp. The kelp growth parameters estimated from kelp measurement data before the harvesting season were positively related to the bottom current velocity. This suggests that the bottom current velocity has a significant effect on kelp growth. The 58 harvesting grounds were classified into two categories based on their growth: those with high kelp growth and those with low kelp growth. Based on a decision tree model, the differences between the two harvesting ground categories were explained by the bottom current velocity, maximum slope, and bottom substrate. In addition, their specific environmental conditions were also quantified. The quantified environmental conditions were also used to create a potential map for the kelp growth in the harvesting grounds. This study provides an understanding of the environmental characteristics of the kelp harvesting grounds, as well as a procedure for mapping the kelp growth potential, thus contributing to the sustainable use of the kelp resources through kelp harvesting ground management and maintenance.This study was supported by the management expense grants of FRA, Japan and by the commissioned project for the survey on the fisheries infrastructure development of the Fisheries Agency “ Development of Methods for Selecting Sites Suitable for the Kelp Harvesting Grounds Based on the Elucidation of Marine Environmental Conditions Favorable to the Kelp Growth (2017–2019)”