World Aquaculture - September 2023


WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2023 1 WORLD AQUACULTURE MAGAZINE WORLD AQUACULTURE magazine is published by the World Aquaculture Society. The home office address is: World Aquaculture Society, PO Box 397, Sorrento LA 70778-0397 USA. P and F: +1-225-347-5408; Email: World Aquaculture Society Home Page: WORLD AQUACULTURE SOCIETY OFFICERS, 2023-24 Humberto Villarreal, President Jennifer Cobcroft Blair, Immediate Past President David Cline, President-Elect Reginald Blaylock, Treasurer Rumaitha Al Busaidi, Secretary DIRECTORS Victoria Tarus Hillary Egna Angela Caporelli Etienne Hinrichsen Shivaun Leonard Yahira Piedrahita Marina M. Rubio Benito, Student Director CHAPTER REPRESENTATIVES John Walakira, African Salin Krishna, Asian Pacific Ik Kyo Chung, Korean Francisco Javier Martínez Cordero, Latin America and Caribbean Anita Kelly, USAS HOME OFFICE STAFF Judy Edwards Andrasko, Director, Killian A. Haydel, Assistant Director, WORLD AQUACULTURE EDITORIAL STAFF C. Greg Lutz, Editor-in-Chief Mary Nickum, Editor Linda Noble, Layout Editor WAS CONFERENCES AND SALES John Cooksey, Executive Director of Conferences and Sales World Aquaculture Conference Management P.O. Box 2302, Valley Center, CA 92082 P: +1-760-751-5005; F: +1-760-751-5003 Email: MANUSCRIPTS AND CORRESPONDENCE Submit manuscripts as Microsoft Word files to Mary Nickum, Editor, World Aquaculture magazine. Email: Letters to the Editor or other comments should be sent to the Editor-in-Chief, C. Greg Lutz at WORLD AQUACULTURE (ISSN 1041-5602), is published quarterly by the World Aquaculture Society, 6203 Jonathan Alaric Avenue, Gonzales, LA 70737 USA. Library subscription price $50 annually for United States addresses and $65 annually for addresses outside the United States. Individual subscriptions are a benefit of membership in the World Aquaculture Society. Annual membership dues: Students, $45; Individuals, $65; Corporations (for-profit), $255; Sustaining, $105 (individuals or non-profits); Lifetime (individuals) $1,100. Periodical postage paid at Sorrento Louisiana and additional mailing offices. Twenty-five percent of dues is designated for subscription to World Aquaculture magazine. POSTMASTER Please send address changes to World Aquaculture Society, PO Box 397, Sorrento, LA 70778-0397 USA. ©2023, The World Aquaculture Society. W RLD AQUACULTURE VOL. 54 NO. 3 SEPTEMBER 2023 13 the Journal of the World Aquaculture Society Editor’s Choice Awards 15 Co-culture of Grazer Species and Bivalves: an Opportunity as a Nature-based Solution for Food Darien D. Mizuta, William Walton and Ricardo L. Cruz 18 Evolution of Aquaculture Value Chain Development in Zambia — Approaching a Century of Demonstrated Resilience Alexander Shula Kefi 22 Structural Changes of the Digestive Tract of Barred Sand Bass Paralabrax nebulifer During the Larval Period O. Rosales-Navarro, M.O. Rosales-Velázquez and J.L. Ortiz-Galindo 26 Role of Oysters and Sediment in Anoxia Processes in a Shellfish Farmed Lagoon Julie Le Ray, Béatrice Bec, Annie Fiandrino, Marion Richard 30 Sewage Fed Aquaculture in East Kolkata Wetland R. N. Mandal, Farhana Hoque, S. Adhikari, B. N. Paul, and D. N. Chattopadhyay 35 Can High Salinity Affect the Catfish Pathogen Aeromonas hydrophila? Haitham H. Mohammed, Wenlong Cai and Timothy J. Bruce 39 Find My Oyster — A Software Tool for Improved Bottom Culture Shellfish Farming Gudjon Magnusson 42 Utilization of Exogenous Enzymes in Aquafeeds Mir Ishfaq Nazir, Irfan Ahmad Bhat, Ngairangbam Sushila and Jaffer Yousf Dar 46 Effect of Protein Reduction with Indispensable Amino Acid Supplementation in Nile Tilapia Diets Sara Youssef, Shimaa M.R. Salem, Rania E. Mahmoud and Tarek I. Mohamed 49 Growth Patterns and Early Development of Pacific Seahorse Hippocampus ingens Under Culture Conditions Renato Peña and Eliezer Zúñiga-Villarreal 54 Freshwater Cage Culture in India: Prospects and Constraints Rameshwar Venkatrao Bhosle, Stephen Sampath Kumar and Somu Sunder Lingam 58 The Diverse Research Applications of Fish Cell Lines Suja Aarattuthodi 63 Exotic Fish Species Introductions and Risks to Biodiversity and Ecosystems: a Review and Nigerian Perspectives Anthony A. Nlewadim and O. Alum-Udensi 68 The Need for Aquaculture Macrogenetics: Using the Shrimp Industry as an Example E Hu. PhD 70 AUTHORSHIP: Who Actually Wrote It? Mary Nickum, Editor, World Aquaculture Magazine COVER: Multiple species are produced using wastewater from East Kolkata Wetlands, with average daily harvests of 50 tons. See story, page 30. (CONTENTS CONTINUED ON PAGE 2)

2 SEPTEMBER 2023 • WORLD AQUACULTURE • WWW.WAS.ORG Contents (continued) 2 President’s Column 3 Editor’s Note 5 USAS Chapter Report 6 African Chapter Report 8 Asian Pacific Chapter Report 10 Korean Chapter Report 11 Latin American and Caribbean Chapter Report 70 Conference Calendar 71 Future Conferences and Expositions 72 Membership Application President’s Column An overwhelming conclusion after our World Aquaculture Conference in Darwin is that Aquaculture can produce high quality, nutritious seafood with sustainable, economically viable and socially responsible systems. Nevertheless, significant challenges were also identified for current producers, challenges that affect the potential for future growth. The World Aquaculture Society is always looking at ways to contribute to global aquaculture development and I’d like to use this column to discuss some of the main challenges the industry is facing in 2023. Similar to other animal protein-producing industries, problems affecting aquaculture relate to production costs (particularly feed), market prices, diseases and genetic selection associated with broodstock quality. Climate change is a major issue affecting production, and sustainability and potential user conflicts with local communities are very relevant. Feed cost. Increases are associated with the limited availability of fishmeal and fish oil, and the production and distribution challenges of fertilizers and vegetable proteins, such as soy and wheat. This means that we must look at alternative protein and essential fatty acid sources, reduce the environmental impact by improving ingredient selection, support the development of genetic lines of commercial species that require less animal protein and support diversification towards more efficient species. Market prices. Generalized inflation affects production and transportation costs and influences seafood consumption, as disposable household income becomes limiting. Low demand puts downward pressure on farm-gate prices for commodities (such as shrimp). This puts some farmers on the brink of bankruptcy, leading to industry consolidation where only the enterprises using efficient technologies will succeed. Diseases. Significant losses due to diseases occur in all major producing species. Industry strategies have been varied, with the adoption of “survivor” lines and a reduction of stocking density in some cases (shrimp), to the implementation of disease-free stocks and genetic selection for specific traits (salmon). However, problems persist and opportunities exist to develop and implement strategies for disease prevention, better biosecurity control and early detection of diseases. Genetic Selection. Successful programs for salmon, tilapia and shrimp have contributed to production increases in aquaculture. However, implementation of selected lines is still very limited in the industry and claims of performance for some commercial “genetic lines” are frequently unsubstantiated. It is also important to recognize that small producers cannot usually benefit from these programs, so establishing National Genetic Programs for relevant species, based on disease-free stocks and molecular-based genetic selection for specific traits, is desirable. Sustainability and Climate Change. Over the years, the narrative related to aquaculture has focused on habitat destruction, contamination, excessive use of antibiotics and escapes that may cause a loss of genetic diversity and spread diseases. Modern aquaculture systems are sustainable, less polluting than other protein production systems and have a lower carbon footprint, so we need to promote a new narrative. Climate change will undoubtedly affect industry development (the 2023 ENSO is a present reminder) and a systems approach involving all stakeholders is necessary to counter its effects. On the other hand, aquaculture is facing challenges from other human activities. These user-conflicts, sometimes related to property rights, sometimes associated to misconceptions of potential impacts on environment, fisheries, etc., limit development. We need aquaculture included in national land-use plans as an independent agribusiness so that investors can have legal certainty. The World Aquaculture Society, as the most relevant aquaculture association worldwide, must facilitate the generation and dissemination of knowledge among its members and society in general, through conferences, workshops, and effective use of social networks. We now offer free WAS Membership to students worldwide, have an openaccess Journal that is very well regarded by the scientific and industry communities and have also made the World Aquaculture Magazine open-to-the-public. I believe these actions will help the industry solve its challenges. Similarly, effective collaboration with other specialized organizations will be vital in providing information that contributes to the definition of public policies to develop sustainable, socially responsible, and economically viable aquaculture projects worldwide. I encourage you as Members of our Society to identify potential areas where you can contribute to improve research, technology development and production innovation, and share your ideas and projects at our conferences and in our publications. Feel free to contact me, or our Board and Chapter representatives and the World Aquaculture Magazine Editor, Prof. Greg Lutz, with your thoughts. I’m looking forward to meeting you at one of our next World Aquaculture or regional conferences. Cheers. — Humberto Villarreal, President

WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2023 3 Editor’s Note We’ve all heard the projections of how important the role of aquaculture will be to meet the needs of a growing population over the next several decades. But what kind of environmental conditions will future aquaculture producers have to operate under? A number of climate-related changes that impact our industry have already taken place and the trends show no sign of slowing or reversing. In fact, the term “the new abnormal” has emerged in recent months to describe weather-related events that would once have seemed unlikely. The global average temperature for July of this year was confirmed to be the highest for any month ever. At least, since we began keeping records in the 1800s. Global average sea surface temperatures also reached record high levels in July, and marine “heatwaves” were apparent in Mediterranean and Caribbean waters. But temperature itself is just the tip of the iceberg (pun intended). Other, related, trends are equally ominous. According to the National Aeronautic and Space Administration (NASA), carbon dioxide levels in our atmosphere have increased from less than 320 ppm in 1960 to over 420 ppm today. The resulting ocean acidification is a consequence many of us have had to confront firsthand. Similarly, atmospheric methane levels have increased from 1645 ppb in 1984 to 1912 ppb in 2022. That may not seem like a lot, but the amount of methane in the atmosphere has more than doubled over the past two centuries, and methane is a potent greenhouse gas. Fortunately atmospheric methane only persists for about a decade, but the CO2 we pump into the atmosphere will remain for centuries. The oceans’ 5-year average gain in heat content is now approximately 350 zettajoules, up from a baseline of 0 in 1957, and the past 30 years have seen global sea level rise by almost 10 cm. These factors combine to greatly increase the impacts of typhoons, hurricanes and tropical storms on coastal (and occasionally inland) aquaculture facilities, especially in the tropics and sub-tropics. Warmer temperatures and changing precipitation patterns have contributed to recent catastrophic wildfires in many locations, including Hawaii, Canada, Portugal, northern Europe and even Siberia. Drought conditions, both temporary and prolonged, appear to be more common occurrences than they were in the past. The term “flash drought” is now used to describe conditions that arise very quickly as a result of the combined effects of extreme heat and lack of rainfall. “Flash drought” conditions have been implicated in devastating fires on several continents in recent years. Longer-term changes in precipitation patterns have caused prolonged droughts in several regions, such that many reservoirs and lakes have literally dried up. On the other hand, flooding of unusual severity has occurred in many parts of the world over the past year including China, Korea, Japan, northern India, Pakistan, Norway, Germany, Slovenia, Russia, and various locations in the US. Apart from monsoon events and tropical storms, inland flash flooding events are becoming more frequent. Around the world it is not uncommon to hear reports of people receiving weeks’ worth of rain in a matter of hours or days. A group of researchers from NASA, California State University, the Bay Area Environmental Research Institute and the Climate Analytics Group has published a study that may help answer the question I posed above (Park et al. 2023). Most climate models suggest that after global temperatures reach a threshold of 2o C above pre-industrial levels, a cascading series of climate changes may be irreversible, and most models suggest we will reach that threshold at some time in the 2040s. According to the study results, aquaculture producers will have to deal with near-surface air temperatures (over land) between 2.3o and 2.8o C higher than present-day values on average, with the most extreme increases (up to 4o C) occurring at northerly latitudes. Heat stress on human health is expected to increase across the entire planet, with the greatest increases occurring in South America, Central Africa, Canada and Russia. The study suggests that changes in precipitation will be quite variable by region, but almost every important aquaculture production region will be affected. Northern latitudes, sub-Saharan Africa and northern India will experience more rainfall than they currently do, while large portions of South and Central America will see significant reductions. Changes in precipitation are also predicted to alter the types and intensity of solar radiation, and weather conditions conducive to wildfires are especially predicted to increase in the Americas, Europe, and southern Africa. Last year, Pakistan’s Prime Minister, Shehbaz Sharif, addressed The path before us FIGURE 1. Predicted near surface air temperature change by the 2040s. From Park et al. 2023. FIGURE 2. Predicted change in annual precipitation by the 2040s. From Park et al. 2023. (CONTINUED ON PAGE 72)


WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2023 5 Sinking to floating. Sub-millimeter to pellet. When you select an Extrusion Processing System from Extru-Tech, you have a complete Universe with the ability to maintain size yields over 95%. As your business evolves, you have the flexibility to change your finished product without the need for significant capital expenditures. In an industry where aquafeed can represent 50% of your operation cost, don’t gamble. Contact Extru-Tech and optimize your flexibility and profitability. OUR UNIVERSE EXTRU-TECH AQUAFEED UNIVERSE Sub 1 Millimeter Pellet Master Your Aquafeed Universe P.O. Box 8 100 Airport Road Sabetha, KS 66534, USA Phone: 785-284-2153 Fax: 785-284-3143 ET-338F.indd 1 1/28/21 8:46 AM the American Fisheries Society Fish Culture Section are in the process of providing a continuing education course on the statistical program R, to be held at Aquaculture America in San Antonio. Dr. Bradley Richardson will be teaching this oneday course, which will occur the day prior to the conference. If you want to learn R, please plan to attend! The Diversity, Equity, and Inclusion ad-hoc committee has devised a demographic survey, which will be administered during the USAS meetings (except for the triannual meetings). This survey will be administered through Survey Monkey. The survey will appear after you have registered for the San Antonio meeting. Please look for the link and fill out the survey. As always, there is the choice to “do not wish to state.” This survey is confidential and will not be used in publications, only for internal use by the USAS Board. The Election Committee is actively seeking nominations for various positions, and I encourage you to consider running. We U.S. Aquaculture Society The Board has been working diligently on the current USAS initiatives. One initiative, which Carla Schubiger initiated, is the monthly interviews of individuals that are members of USAS. Dr. Schubiger has taken a new position, but fortunately Stephen Pinna has graciously agreed to continue this effort and even expand it beyond USAS members. Learning about those in the aquaculture community is an important aspect to understanding how many different areas are currently being researched, developed, and managed by our members and others. If you have not had a chance to look at these interviews yet, please visit our website at As reported in the last update, the Promotion and Membership Committee has nearly completed the member survey. This survey will help to steer some of the activities of USAS in the future. Once you receive the questionnaire, please feel free to include additional thoughts that you might have that will help us improve the services we try to provide to our membership. The Continuing Education Committee and our friends from CHAPTER REPORTS (CONTINUED ON PAGE 8)

6 SEPTEMBER 2023 • WORLD AQUACULTURE • WWW.WAS.ORG CHAPTER REPORTS As we begin the home-stretch to the much awaited 2nd Aquaculture Africa Conference (AFRAQ23), scheduled for Zambia (13-16 November 2023), I thought I should reflect more on the theme of the event: Resilient value chains in the blue economy. This theme augurs well with what the sector has experienced in recent years – a myriad of emerging threats in addition to known traditional and long-term challenges. Overall, issues related to the high costs of doing business in aquaculture have by-and-large taken center as a knock-on effect to aquaculture development in Africa this season. Sector actors are also still reeling from shocks and supply chain disruptions caused by impacts of COVID-19, impacts of the Russia/Ukraine war and the unstable geo-political situation in some African countries. And yet, we are still in the midst of dealing with some of the most difficult challenges such as climate change, which has largely been blamed on the recent wave of fish farm flooding, water scarcity and other negative impacts. The recent emergence and proliferation of aquatic diseases in some regions has been a cause for concern. Despite a myriad of these challenges, I must applaud the resilience of the sector, which keeps going sustainably and new investments keep cropping up. We have seen general growth and expansion of production around the Great Lakes Region and the Zambezi region – a demonstration that adopting innovations of ensuring the various country contexts and social settings and how the production, supply and market continue to operate sustainably can work under the backbone of a stable macro-economic environment. The key message out of all this, which we hope to discuss more at AFRAQ23 is that there is a desperate need for collaboration among key stakeholders to strongly focus on building elements of a sustainable and innovative aquaculture value chain practice supported by an enabling policy. These include interrelated activities to ensure prevention, preparedness (including early warning), innovative responses and recovery for a wide range of natural, technological and complex disasters that can impact aquaculture operations and livelihoods. The role of developmental agencies and researchers is paramount in the mix. Zambia, the host country for AFRAQ23 offers some lessons on how the country has managed to weather through many of these storms thus remaining one of the fastest growing aquaculture producer countries in Africa. Preparations for AFRAQ23 were given a boost in early August 2023 following the signature of the hosting agreement by Zambia’s Ministry of Fisheries and Livestock. This special gesture means the Government of Zambia is fully committed to collaborate with WAS in ensuring smooth organization of the event through financial commitments, support to the hiring of convention centre, appointment of State Officials to the conference’s National Organizing Committee, national promotions, and high-level officiation to the event among other roles and commitments. I was delighted to personally meet the Minister of Fisheries and Livestock and his delegation in July in Lusaka and to sign the AFRAQ23 hosting agreement on behalf of the WAS. In addition to a well-structured scientific/ technical programme covering all aspects on aquaculture development in Africa, other highlights include special sessions by the FAO and its partners, Africa Union agencies, Southern Africa Development Community (SADC), University of Zambia, World Aquatic Veterinary Medical Association (WAVMA), World Initiative on Soy in Human Health (WISHH), GIZ, and industry sessions spearheaded by our Founding Gold Sponsor, Aller Aqua Ltd and others. Many other session sponsors and exhibitors are increasingly expressing their interest to participate at AFRAQ23. Surely there will be something for everyone there! We are anticipating having the Chapter’s inaugural students’ workshop as well as the first honors and awards ceremony at AFRAQ23. The WAS AC Board will have its Annual Board Meeting and the Chapter’s Annual Business Meeting slated on schedule. A post-conference aquaculture tour is being planned, hopefully on 17th November to Lake Kariba - one of the epicenters for freshwater aquaculture production in Africa, and also to some aquaculture facilities of interest around Lusaka and Kafue. I believe AFRAQ23 will undoubtedly be the best place to be for many of our audience, as we aspire to learn more and connect with a diverse range of aquaculture players in Africa and globally. Make sure you are booked to attend this event! I am a beneficiary and product of the WAS student development programme (since my University days) and I am therefore passionate and excited to see African students benefiting from our products and services. One of my main flagship calls since assuming the AC Presidency was on advocating for a sound WAS AC Student development. I am delighted to report that we have begun domesticating the new WAS student policy in Africa through the recent launch of the WAS AC Student Forum (August 2023) - a platform where African students can connect with each other, embrace new experiences, and expand their knowledge thus leveraging on valuable insights from our diverse network and activities. The process is still under development and is expected to see a user-friendly, free of charge student registration process to WAS. We hope to also conduct regular student webinar sessions, workshops and strategic awards at future AFRAQs. I am grateful to the WAS AC Students Managers Dr. Khalid Salie and Dr. Nyiko Mabasa (Stellenbosch University, South Africa), with support from WAS Student Director (Dr. Nicole Rhody) for taking lead on this initiative. I had hoped to be with some of you at the World Aquaculture 2023 meeting in Darwin Australia. Unfortunately, I could not make it due to visa processing challenges - which admittedly is a major challenge for us Africans to attend some international events. However, I was delighted to hear the Conference was another great success (post-covid); and that the AC reports were highly appreciated by the WAS Board. It was also an honour to have an Africa Aquaculture Session on this global platform - which I understand was well attended by those connected to, or interested in African Chapter (CONTINUED ON PAGE 8)


8 SEPTEMBER 2023 • WORLD AQUACULTURE • WWW.WAS.ORG CHAPTER REPORTS Asian Pacific Chapter The World Aquaculture 2023 meeting, which recently concluded in Darwin with excellent participation from the aquaculture sector in the Asia Pacific, was a great success. The event’s location was outstanding, and the Australian participation was tremendous. Because of the Darwin conference’s success, we anticipate upcoming WAS and APA events with even more excitement. After WA2023, one of WAS-APC’s most important endeavors was to plan ways to engage with potential Asia Pacific regions where our representation is limited. The Pacific Island Countries and Territories (PICT) have an emerging aquaculture industry. A preliminary discussion between the WAS-APC Board and Dr. Tim Pickering, Principal Aquaculture Advisor to the Pacific Community (SPC), was conducted online. Several action points where WAS-APC and the Pacific Community may collaborate to improve the technical and business capacity of aquaculture firms and training in PICT have been proposed as an outcome of this meeting. With the same objective in mind, WAS-APC intends to integrate Cambodia and Nepal, two countries that are now very little involved with the Society aside from a few important industry representatives attending WAS or APA conferences. Plans to hold conferences backed by WAS-APC in Cambodia and Nepal, a technical workshop in Vietnam, and the Aquaculture Innovation Ideation Challenge (AIIC) focused on students, all mentioned in my previous report, are moving forward. Aside from these, WAS-APC partners with the following conferences in 2023: the 10th International Conference on Fisheries and Aquaculture (https://, which will be held in Bali, Indonesia, from 24 – 26 October 2023; The 11th International Fisheries Symposium (IFS) 2023, which will be organized by the ASEAN-Fisheries Education Network and hosted by AIT in Bangkok, Thailand (, from 22 – 24 November 2023; and the GIANT PRAWN 2023 Conference (, organized by AIT in Bangkok, from 27 – 29 November, focused on the aquaculture of freshwater prawns. These events help maintain the significance of WAS-APC in the region, proactively contributing to the aquaculture industry in the Asia Pacific region. Since the 2016 APA conference in Surabaya, Indonesia, which attracted a record number of attendees, there have been significant changes in Asia-Pacific aquaculture. Plans are currently on schedule for the next Asian-Pacific Aquaculture Conference (APA2024) to be held in Surabaya, Indonesia, from 11-14 June 2024. We anticipate increased attendance and interest in 2024. In the coming days, we will provide you with more information about another exciting meeting in Surabaya. — Krishna Salin, President USAS, continued from page 5 encourage those who wish to be involved to self-nominate. If you wish to nominate a person, please make sure that they are willing to run. The President’s Committee, which is made up of all past presidents, is currently reviewing our strategic plan to ensure we are on track to meet our milestones from our last strategic plan. As we are all aware, strategic plans are written to establish goals to be met. But they are also a fluid document that can include items that arise that need to be addressed. Students! If you are not aware, the WAS board passed a resolution that allows for two categories for student members 1) a free membership that if selected DOES NOT ALLOW you to vote, and 2) a paid membership that does allow you to vote. We have had students that have chosen each of these choices. Be aware of the differences when you decide to join WAS. — Anita Kelly, President Africa, continued from page 6 aquaculture developments in Africa. Lastly, let me end by congratulating Dr. Humberto Villarreal for being elected the new President of the WAS, and all new incoming Directors — including our very own WAS AC champions; Etienne Hinrichsen (South Africa) and Shivaun Leonard (USA). The WAS AC is also in the process of electing some office bearers this season, hopefully in October 2023. Let me also congratulate Dr. Greg Lutz for taking on the mantle to be the new chief editor of the WAM. As AC, we stand ready to provide improved and informative articles showcasing aquaculture developments in Africa! This could probably be my second last column before I hand over the mantle to the incoming AC President in November 2023. It has been an exciting two-year journey drafting these summary presidential manuscripts on what WAS AC is doing in serving aquaculture development in Africa. I am forever grateful! I hope to see many of you at AFRAQ23, Zambia! — John K. Walakira, President


10 SEPTEMBER 2023 • WORLD AQUACULTURE • WWW.WAS.ORG CHAPTER REPORTS Release of Contaminated Water from Fukushima Nuclear Power Plant On August 24, Japan began releasing polluted water from the Fukushima nuclear power plant into the ocean. The South Korean government acknowledged that the discharge plan appears technically and scientifically sound; however, it neither agrees nor supports it. The government has been informed that there should be no concerns if the contaminated water is treated and released following international procedures and scientific standards. Nevertheless, many South Koreans are against releasing polluted water. In June, a Gallup Korea survey found that 78% of respondents were apprehensive about seafood contamination caused by the nuclear plant’s water discharge. Aside from the scientific safety of the treated water, the discharge of contaminated water will probably harm consumer confidence and the aquaculture industry. 2023 KOSFAS Conference & WAS KC Report The 2023 Korean Society of Fisheries and Aquatic Science (KOSFAS) Conference was held at Kumho Tongyeong Marina Resort under the theme ‘How to develop ESG-based fisheries in the era of the pandemic’ from July 5 to 7. The Gyeongsang National University, Mokpo National University, Research Center for Marine-Integrated Biomedical Technology Pukyong National University, and the KOSFAS organized the conference. A total of 474 participants attended. There were various opportunities for researchers and industry practitioners to participate and share in the twelve sessions, including ‘Technical workshop for innovation of flow-through digital aquaculture’ by the Aquaculture and Biotechnology Division. The Senior Session featured ‘Functional lipids of marine products’ by Professor Emeritus Bo-Young Jung (Gyeongsang National University), ‘A study on seaweed solutions in response to Korea’s climate crisis’ by Professor Emeritus IkKyo Chung (WAS-Korean Chapter President, Pusan National University) and ‘Current status of artificial eel production technology’ by Professor Emeritus Chang-Hee Han (Dong-Eui University). During the conference, the WAS-Korean Chapter showed chapter reports as a short presentation during Professor Emeritus Chung’s talk. The main contents of the report were the Emergency Committee (EC) of the 23-24 term approval by the WAS Board of Directors, and the appointment of Professor Han-Kyu Lim (Mokpo University) as President-Elect. The EC, chaired by Professor Emeritus Ik Kyo Chung, the Immediate Past President, will bring the number of members back to normal, prepare plans for improvement by revising the bylaws, and put the KC on the standard track. NIFS & KMI - Joint Workshop of Flounder Aquaculture Industry The National Institute of Fisheries Science (NIFS), Ministry of Oceans and Fisheries, held a two-day workshop from June 8 to 9 with the Korea Marine Fisheries Development Institute (KMI) to analyze the effects of flounder research and development (R&D) on the industry and draw implications. The workshop was organized to bring together natural and social scientists from both organizations to comprehensively analyze the results of flounder R&D conducted by the institute. NIFS began research on flounder artificial seed production in 1981 and secured full-cycle aquaculture technology in 1987, laying the groundwork for the industrialization of flounder aquaculture. Since then, research and development in various fields such as culture, feed, pathology, and breeding have been promoted, contributing to establishing flounder as a representative fish farming species in Korea. So far, flounder aquaculture production has increased 2,000 times from 20 tons in 1987 to 45,884 tons as of 2022, recording the most prominent production (50.2%) among aquaculture species in Korea. However, there has been a lack of comprehensive analysis of the effects of R&D on flounder varieties. In this workshop, there were presentations and discussions from both institutions on (1) the status of flounder R&D promotion by sector, (2) sharing approaches to R&D industrial effect analysis, (3) discussing new analysis frameworks, and (4) exploring ways to model and quantify industrial effect analysis and future promotion directions. In addition, technology commercialization performance, industrialization indicators, technical guidance, education, and academic activities were compared and evaluated using the Analytic Hierarchy Process (AHP) technique. President Dong-Shik Woo (NIFS) said, “Based on the analyzed results, we will promote more effective and strategic flounder R&D to support the industry and apply it to R&D in other fields.” Aquaculture Disaster Insurance by 2027 - Increasing Number and Coverage The Ministry of Oceans and Fisheries (MOF, Minister SeungHwan Cho) established the ‘1st Master Plan for the Development of Disaster Insurance for Aquaculture Products (2023~2027)’ on June 20, which outlines key strategies over the next five years. This is a statutory plan established under the Agricultural and Fishing Villages Disaster Insurance Law, which aims to promote disaster insurance for agricultural and fisheries products, and is the first of its kind. The plan will expand the items covered so that more fishermen can prepare for losses from natural disasters through aquaculture insurance and strengthen the guarantee of disaster insurance by introducing the “cost compensation method” for the first time, which guarantees the production costs invested until the loss occurs. In addition, it will expand premium rebates for long-term continuous policyholders and accident-free policyholders to reduce the burden of insurance and diversify the scale of premium support according to the level of collateral, farm area, and income level to stabilize the management of small-scale fishermen. NIFS and WOAH Co-Host International Workshop on Aquatic Animal Diseases in Asia-Pacific The National Institute of Fisheries Science (NIFS), Ministry of Korean Chapter

WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2023 11 CHAPTER REPORTS Oceans and Fisheries, held an International Workshop on Aquatic Animal Diseases in Busan from June 26 to 28 in collaboration with the World Organization for Animal Health (WOAH). Due to the influence of the COVID-19 pandemic, this workshop was held for the first time in four years with about 40 participants, including national officials from 26 countries in the Asia-Pacific region. President DongShik Woo (NIFS) gave a welcome speech, saying, “At a time when the importance of responding to infectious diseases has recently been recognized due to COVID-19, it is essential to strengthen disease management capabilities by sharing research results and experiences of each country. The NIFS must actively cooperate with the international community to promote the production and trade of disease-free aquatic products.” FIRA’s Seaweed Blue Carbon Workshop Korea Fisheries Resources Agency (FIRA, President ChunWoo Lee) invited 50 experts from academia and private companies to a workshop in BEXCO, Busan, on July 20 and set out to lay the groundwork for international certification of blue carbon in sea forests. Currently, sea forests (seaweeds and kelps) are known as potential blue carbon candidates that meet five of the international community’s six core standards recognized as blue carbon, excluding IPCC certification. Certification as a new carbon sink is highly likely. The workshop consisted of presentations on blue carbon-related research achievements and trends, and an expert panel discussion to review the potential for blue carbon certification and share the process of promoting international accreditation. — Ik Kyo Chung, President The aquaculture production forecast for the Latin American region is again, this year, telling a well known story as witnessed in recent years: impacts from different external sources, learning to adapt to them, and many tests of farmers’ and their communities’ resilience. In particular, the commercial tilapia industry in the continent is facing new challenges with impacts from diseases. Countries like Colombia and Mexico have suffered major impacts and mortalities. In the latter country, combined effects of extreme drought in the southern Pacific States in the first semester of the year have meant huge impacts for commercial cage culture. Many farmers have shut down operations and the end of the year balance doesn’t look good currently. In any case, this reminds us of the inherent increasing risks in aquaculture, and the obligation of a multi-actor planning of operations (governments, industry, academy) accordingly. Sustainability of aquaculture is really being tested and only joint actions and commitments from the different economic agents involved in the chain values will bring real solutions. This comes at a time when the world is discussing the transformation of agrifood systems to comply simultaneously with environment, health and food objectives, while taking care of rural communities and people in poverty and hunger. At the core of this transformation is the need to enhance food security, nutrition, and resilience to crises through increased aquaculture productivity and income for farmers’ households. This is becoming a huge challenge for small- and medium-scale aquaculturists, and for those raising fish for their own consumption. We must seriously discuss how to efficiently implement nature-positive, nutrition-sensitive and climate-smart aquaculture systems of all sizes. At the beginning of June, the High-Level conference on World Food Security took place at the FAO in Rome. Aquaculture was one topic in the Conference, although not as prominent as we might desire, considering its relevance for food security in the world. Food systems will be prominent again on the International Agenda, with investment and productivity becoming critical factors. There was consensus at the end of the Conference on the urgent need to help developing countries and those in transition to expand agriculture and food production, and to increase investment, agribusiness and rural development. This very easily translates and coincides with objectives for world aquaculture. Against this framework, our forthcoming LACQUA 2024 Congress, to take place in Medellín, Colombia, will be an excellent opportunity to discuss these new challenges together and unite as a region to find solutions. Our WAS Conferences are an excellent blend of academic work and industry sessions and perspectives. We will organize the event, calling for governments and industry interaction through special topic sessions, to come out with advances in these important issues. Financing remains critical, and constrains operations in small and medium-sized aquaculture enterprises. However, few advances have been seen in this topic. Again, we will set the table in our LACQUA 24 Congress to bring together the main stakeholder voices for discussions and commitment to action. We hope to see all of you in Medellín, Colombia, September 24-27 for LACQUA 2024!!!! — Francisco Javier Martinez Cordero, President Latin American and Caribbean Chapter The aquaculture production forecast for the Latin American region is again, this year, telling a well known story as witnessed in recent years: impacts from different external sources, learning to adapt to them, and many tests of farmers’ and their communities’ resilience.


WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2023 13 • Santigosa, E., Olsen, R. E., Madaro, A., Trichet, V. V., & Carr, I. (2023). Algal oil gives control of long-chain omega-3 levels in full-cycle production of Atlantic salmon, without detriment to zootechnical performance and sensory characteristics. Journal of the World Aquaculture Society, 54(4), 861–881. Available at: https:// This study assessed the suitability of partial or full (100%) replacement of fish oil (FO) with microalgal oil (AO) in Atlantic salmon diets. This represents a novel approach as it is one of the first studies to follow fish through the entire production cycle from post-smolt (145 g) to a 3 kg harvest size. Three experimental trials were conducted consecutively and fish were fed a control diet containing FO as the main source of omega-3 LC-PUFA, with test diets containing graded levels of AO and other plant oils (rapeseed and soybean). No differences in zootechnical performance were found and results showed that AO replacement did not negatively affect growth, muscle quality, or EPA/DHA levels in fish fillets. A variety of sensory characteristics were also compared and raw salmon muscle from fish fed AO diets had favourable odor, taste, texture, appearance, or color. This study clearly demonstrated the suitability of AO as an effective alternative ingredient in salmon feeds and fully supports the idea that AO is a suitable FO replacement for salmon feeds and greater use of AO would reduce the marine footprint associated with aquafeeds. • Shaughnessy, B. K., Almada, A., Thompson, K., Marvier, M., & Kareiva, P. (2023). Are all benefits equal? An exploratory analysis of coastal perspectives of seafood farming expansion in the United States. Journal of the World Aquaculture Society, 54(4), 899–914. Available at: This interesting study looks at how residents of coastal areas in western and northeastern US states view seafood farming and provides suggestions on how messaging on the benefits of aquaculture can be adjusted to influence public opinion. The economic importance of aquaculture is often emphasized as a benefit but in general, the US public is not well informed and unaware of the Journal of the World Aquaculture Society Editor’s Choice Awards other potential benefits of seafood farming. This study took a unique message-testing approach to survey 1) how opinions about seafood farming vary in relation to geography, prior familiarity with aquaculture, and sociodemographic attitudes; 2) how malleable opinions on aquaculture are; and 3) what benefits of marine aquaculture (especially seaweed farming) are viewed as reasons to support expansion of the industry. It was found that attitudes and opinions of marine seafood farming are highly linked to prior familiarity with aquaculture, but that this is highly malleable. The researchers suggest that primary messaging should emphasize sustainability and environmental benefits and not economic or social benefits. Focusing more on this message for coastal residents may be important and represent a better tool for gaining public support for the expansion of seafood farming in the US. • Campanati, C., Arantzamendi, L., Zorita, I., Juez, A., & Aldridge, D. C. (2023). Microencapsulated diets using thraustochytrids and macroalgae side streams for nursery rearing of Mytilus galloprovincialis spat. Journal of the World Aquaculture Society, 54(4), 994–1012. Available at: Bivalve production is expanding globally and mussel farming plays an important role in such expansion. This study looks at ways to improve hatchery spat production for the European mussel, Mytilus galloprovincialis. The basis of spat production relies on having reliable diets that can be applied in a cost-effective manner. The authors conducted feeding trials that tested a variety of diets to determine if there were differences in growth and survival. What they found was that microencapsulated feeds produced by using a mixture of micro and macroalgae provided 100% substitution in the diet of M. galloprovincialis spat. Growth and survival were similar in comparison to a commercial diet control and other treatments. They suggest that using microencapsulated feeds for spat production can replace commercial microalgal diets and significantly reduce feed costs. — Ken Cain, Executive Editor, JWAS From Santigosa et al. 2023


WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2023 15 the gear clean and, at the same time, promote oyster production and reduce labor associated with biofouling removal. Biofouling requires the frequent cleaning of farming gear to remove unwanted attached organisms and is a major cost to shellfish growers. The expectation is that urchins could assist in that task by feeding and moving around the gear, thus potentially lowering the need for biofouling management including commonly used methods on commercial farms such as freshwater baths, brine dips or periodic air drying techniques. For this project, local and native Atlantic purple urchins (Arbacia punctulacta) were cultured with native Eastern oysters (Crassostrea virginica). A. punctulacta is an omnivore and feeds on a variety of food, including algae when it is abundant and other animals when algae are less available (Gianguzza and Bonaviri 2013). For this project, urchins were stocked into bottom cages, either with or without grow-out bags (Figure 1), as this is the most common method of oyster culture in Virginia. The intention is to assess co-culture feasibility in commonly used methods and its possible positive effects, in order to provide an option of a farming strategy that could be adopted by the industry across a range of scales. The in-situ experiment was deployed in a shallow subtidal area in Bradford Bay close to VIMS Eastern Shore Laboratory, The US is the top seafood importer in the world and a big consumer of shellfish. Given this opportunity for domestic production, shellfish growers and related seafood businesses, including restaurants and chefs, have expressed interest in innovative forms of aquaculture that bridge farming efficiency and marine conservation spheres, such as restorative aquaculture or regenerative aquaculture. This has fueled interest in new aquaculture species for the national seafood market and the constant improvement of sustainability of farming management, both in environmental terms and social aspects. Combining new species with improved sustainability can be challenging, but co-culture could be one of the answers. Co-culture is the farming of more than one species in the same place and, in this case, farming in the same gear. Following the interest and bottom-up initiatives of many American farmers who strive to diversify their farming with more than one species, there has been enthusiasm to revisit the feasibility of growing grazer species, such as native urchins, with the long-standing traditional oyster industry. While previous projects have explored this possibility, they have not translated to the commercial industry. There was a need for evidence-based results in practical applications that can promote wide commercial adoption. A co-culture project, conducted at Virginia Institute of Marine Science (VIMS) and funded by the Atlantic States Marine Fisheries Commission (ASMFC) led by NOAA, is currently ongoing. The idea is simple: deploy urchins together with oysters inside farming bags or bottom cages to keep the urchins fed and keep Co-culture of Grazer Species and Bivalves: an Opportunity as a Nature-based Solution for Food Darien D. Mizuta, William Walton and Ricardo L. Cruz FIGURE 1. Atlantic purple urchins and Eastern oysters deployed a) in faming bags and b) directly in cages for a feasibility experiment of new species farming and farming management control of biofouling. (Photo credits: bag: William Walton; cage: Darien Mizuta). FIGURE 2. Sizes of urchins currently in use in the project: juveniles (25 mm to 40 mm shell diameter), and adults ( > 45 mm shell diameter). (Photo credit: Darien Mizuta). (CONTINUED ON PAGE 16) a b

16 SEPTEMBER 2023 • WORLD AQUACULTURE • WWW.WAS.ORG testing two sizes of urchins, juveniles and adults (Figure 2), with two urchin stocking densities of relatively low (10 urchins) and high (20 urchins) numbers of grazers. The experiment also included control cages where no urchins were added, simulating traditional oyster monoculture in the area. Preliminary results show positive control of biofouling by the urchins (Figures 3, 4 and 5), although a slight tradeoff between the condition index of oysters and biofouling control provided by urchins may exist. Gonads of urchins improved in condition, measured as the ratio between the weight of the soft tissue of interest and the whole body during summer but decreased in condition during winter (Table 1). The decreased condition in winter suggests food limitation, as also noted in previous investigations (Hill and Lawrence 2003). Conditions of oysters were consistent and considered good in both preliminary experiments (Table 1). A similar project with the common periwinkle (Littorina littorea) was also deployed near VIMS Gloucester Point campus (Figure 6) as an evaluation of a grazer species that tolerates a lower salinity than the urchins used in the first trial. Despite preliminary evidence that both urchins and periwinkles help keep the farming gear cleaner, one of the main limitations observed to date is the mortality of the added grazers, particularly the urchin species. While survival rates of the oysters were higher than 90 percent in all treatments, the winter experiment was terminated after a 100 percent urchin mortality event following a winter storm. Atlantic purple urchins appear to be extremely susceptible to stress. Additionally, it is likely that there was food limitation, at least for the adults, at high density. In a pilot test, periwinkles were preyed upon by crabs when deployed in intertidal racks. The current subtidal deployment is ongoing and the periwinkles seem to be thriving, despite not being in their natural habitat on grass on shore. Sustainable Solutions and Economic Effects While technological innovation abounds recently in aquaculture, with “disruptive” highend innovations, many shellfish growers may find it difficult to afford or incorporate new technologies. This coculture approach has the potential to bring environmental and societal benefits, adhering to the International Union for Conservation of Nature’s standards for Nature-based Solutions (NbS; IUCN 2020). Firstly, it addresses the provenance of nutritious seafood with less expensive management, potentially adding a new production crop in the same leased farm area and with the same equipment. Secondly, it can be scaled out and adaptatively managed based on frequent monitoring and evaluation of the efficacy of the coculture, therefore assuring intended results. It can also increase ecosystem integrity by using another native species to control biofouling, and restore native urchins to areas where they have disappeared. Alternatively, FIGURE 3. Example of quadrats showing biofouling material differences of treatments inside farming bags; a) juveniles - high density, and b) control with no urchins. FIGURE 4. Comparison of biofouling mesh plate samples showing basket with and without urchins (Attribution disclosure: This graph has been designed using resources from ‘iamwildan’ found at FIGURE 5. a), Atlantic purple sea urchin spawning, and b), details of its Bordeauxcolored roe: a possible new seafood item? (Photo credits: urchin spawning, William Walton; detail of roe, Ricardo Cruz). a b a b