The Aquatic Animal Welfare Research and Practice Seminar: Strengthen Animal Welfare Research and Application to Promote Sustainable Development of the Seafood Industry

Abstract

Aquatic animal welfare has been gaining increasing attention globally in the last few years. The Aquatic Animal Welfare Research and Practice Seminar was held in Hangzhou, China, from 28th to 29th March 2025. The Seminar gathered leading scientists and industry stakeholders from across the world who presented their recent research in aquatic animal welfare. This report presented the seminar’s key outcomes and discussions, highlighting current advances, challenges and future directions in aquatic animal welfare research and implementation.

1. Introduction

The seafood (in this conference report, the word “seafood” refers to finfish, shellfish and crustaceans from both the sea and freshwater) industry has become one of the fastest-growing sectors in global animal food production, particularly in Asia, which accounts for about 75% of the combined global fisheries and aquaculture output [1]. Though wild capture fisheries are reaching their biological limits due to full exploitation or overfishing in the last few years, aquaculture continues to expand in response to rising global demand for seafood; projected to increase by at least 32% by 2030, it is poised to play a central role in ensuring food security, improving nutrition, and advancing several of the United Nations Sustainable Development Goals [2].

As the seafood industry rapidly develops, aquatic animal welfare is gaining increasing attention from consumers, retailers, and policymakers. Major supermarket chains, such as Tesco, are now requiring welfare standards for the seafood they purchase and sell. Governments and international organizations are also prioritizing aquatic welfare. The World Organisation for Animal Health (WOAH), for instance, has incorporated aquatic animal welfare into its global aquatic health strategies, underscoring its growing global importance [3]. Certification bodies such as the Aquaculture Stewardship Council (ASC) have also begun to recognize welfare standards as essential elements of sustainable and responsible seafood production, alongside environmental and food safety considerations.

Over the past two decades, scientific understanding of aquatic animal welfare has progressed significantly in Western countries, facilitating the development of evidence-based frameworks to guide welfare practices. More recently, this area has garnered increasing attention within both academic and industry spheres in China. As the world’s largest producer of seafood—encompassing both capture fisheries and aquaculture—China occupies a strategically important position in the global discourse on aquatic animal welfare. Its vast production scale, ecological and species diversity, and substantial influence in international seafood markets collectively underscore its potential to shape the evolution of welfare standards and practices worldwide.

In recognition of these developments, the “Aquatic Animal Welfare Research and Practice Seminar” was convened on 28–29 March 2025, at Zhejiang University, Hangzhou, China. The seminar brought together over 170 participants, including researchers from more than 80 institutions and representatives from approximately 20 leading aquaculture enterprises, with an additional 3000 individuals attending via livestream. Organized by Zhejiang University in collaboration with the Catch Welfare Platform and supported by several national partners, the seminar focused on advancing the science and practice of aquatic animal welfare. Thematic sessions addressed welfare-related research progress, technological innovations, and practical challenges spanning breeding, farming, transport, harvesting and slaughter. This report presents a synthesis of the seminar’s key outcomes and discussions, highlighting current advances and future directions in aquatic animal welfare research and implementation.

2. Main Text

2.1. Opening Speeches

The seminar on aquatic animal welfare commenced with opening remarks delivered online by Academician Shaojun Liu of the Chinese Academy of Engineering. As a leading expert in fish breeding in China, Academician Liu reflected on the emerging concept of aquatic animal welfare, emphasizing its role in prompting a deeper consideration of how to balance respect for animals with their utilization to meet human needs. He highlighted the strong interconnections between animal welfare and key aspects of aquaculture—namely, breeding, management, and marketing—and asserted that ethical treatment of aquatic animals leads to long-term benefits for producers. He concluded by advocating for science-based approaches to sustainable aquaculture, grounded in a respect for animals and aimed at achieving mutually beneficial outcomes for both animals and humans.

Following this, Professor Ying Liu, Dean of the College of Biosystems Engineering and Food Science at Zhejiang University, delivered a welcome address on behalf of the organizers. He extended greetings to participating scholars, experts, and industry representatives and provided an overview of Zhejiang University’s research efforts in the area of aquatic animal welfare. Professor Liu emphasized that animal welfare remains a critical and meaningful research domain for both aquaculture and the broader fisheries sector. He underscored the importance of maintaining scientific rigor and methodological integrity in advancing welfare standards in both academic and industrial contexts.

Representing the international participants, Dr. Hans van de Vis, Senior Researcher at Wageningen Livestock Research, offered a welcome speech. He noted that aquatic animal welfare is a relatively nascent topic not only in China but also globally. Nevertheless, it has gained increasing attention in recent years, appearing more frequently in public policy discourse. Dr. van de Vis called for enhanced international collaboration and knowledge exchange to promote progress in aquatic animal welfare science and its application within the industry.

2.2. Presentations

Presenter: Dr. Tore Kristiansen, Senior Researcher and research director for animal welfare (retired), Institute of Marine Research, Norway.

Presentation Title: The Amazing World of Fish.

In his talk, Dr. Kristiansen provided an engaging overview of the biological and cognitive complexity of fish, emphasizing their diverse sensory systems and advanced behaviors. Drawing on recent scientific findings, he illustrated that fish are capable of learning, memory retention, spatial navigation, and even tool use. He also presented evidence supporting the capacity of fish to experience pain, underscoring the ethical implications for aquaculture and fisheries practices.

The presentation also addressed the global decline in fish populations and risk of species extinction, identifying key contributing factors such as habitat loss, overexploitation, climate change, and pollution. Dr. Kristiansen concluded by highlighting the importance of safeguarding aquatic ecosystems and maintaining biodiversity and abundance. He emphasized that advancing aquatic animal welfare not only improves the lives of fish but also contributes to the sustainability and resilience of aquatic food systems.

Presenter: Dr. Jian Zhu, Chief Scientist of the National Freshwater Fish Industry Technology System.

Presentation Title: Innovative Green and Healthy Farming Technologies to Enhance Fish Welfare.

In his presentation, Dr. Zhu emphasized the need for greater attention to animal welfare within the context of China’s current agenda for “green development of aquaculture.” He argued that the advancement of aquaculture sustainability must include welfare considerations as a core component. To this end, he proposed the promotion of integrated breeding and propagation models driven by technological innovation. Dr. Zhu highlighted several key areas for improvement, including the application of water quality regulation technologies to optimize pond farming systems, the restoration of farm ecological environments, and the enhancement of aquatic biosecurity. He also identified the adoption of artificial intelligence-based management systems as a promising avenue for achieving significant improvements in aquatic animal welfare.

Presenter: Prof. Sonia Rey Planellas, University of Stirling, UK.

Presentation Title: How Can Behavioral Research Improve Fish Welfare?

Professor Rey Planellas emphasized the important role of aquatic animal behaviour research in improving fish welfare. In her presentation, she reviewed the key recent research developments on fish behaviour in aquaculture for improving welfare, such as the domestication and behavioural adaptation in fish, environmental enrichment in aquaculture systems, feeding strategies and social behaviours, lighting and photoperiod effects on fish behaviour, behavioural genetics and selective breeding, and so on. She gave an example of how to use precision fish farming to understand the behaviour of salmon in pens using AI-powered systems and digital vision. By catching the activity and group social behaviour of fish in the cage with cameras, farmers could be informed with more knowledge about fish through analysing fish behaviours, in order to detect early warning indicators on welfare and health issues and take actions to prevent disease outbreaks.

Presenter: Dr. Hans van de Vis, Senior Researcher of Wageningen Livestock Research.

Presentation Title: A Structured Approach to Assessing Live Transport, Stunning, and Slaughter of Farmed Fish.

Dr. Hans van de Vis’s presentation covered two parts. In the first part, he emphasized the importance of welfare risk assessment in safeguarding fish welfare and introduced the systematic risk assessment methods. He detailed the four necessary parts of a well-structured risk assessment: hazard identification, hazard characterisation, exposure assessment, and risk characterisation. The risk assessment not only helps the farmers to prioritise the main fish welfare hazards but also helps the researchers to prioritise their research. In the second part of his presentation, Dr. Hans van de Vis used the case studies of assessing live transport of African catfish, and stunning and slaughter of farmed fish as examples to show how to collect the data that are needed for risk assessment.

Presenter: Prof. Dapeng Li, Vice President of Huazhong Agricultural University.

Presentation Title: The Impact of Farming Space and Stocking Density on Fish Welfare.

Prof. Dapeng Li began by introducing various pond-based recirculating aquaculture systems and discussed the biological and ecological effects of fish stress. He introduced the concept of the environmental biological effect of space from his recent research and related references, which demonstrates how different stocking density affects fish within the same farming space, and how different space sizes affect fish within the same stocking density. Through data analysis on the relationship between space and species such as grass carp, European seabass, and Atlantic salmon, Prof. Li demonstrated that taking both farming space and stocking density into account leads to improved fish welfare and, ultimately, better aquaculture outcomes.

Presenter: Dr. Michael Breen, Senior Researcher of Marine Research Institute, Norway.

Presentation Title: Catch Welfare Research in Norwegian Fisheries.

Dr. Michael Breen emphasized that research into catch welfare not only helps minimise the injury and stress of fish, but can also contribute to both product quality and sustainability. He presented his team’s recent study on catch welfare in the commercial purse-seine fishery for Atlantic mackerel (Scomber scombrus). This study showed that mackerel welfare can be negatively impacted by crowding during purse-seine capture, affecting fillet quality in retained fish and post-crowding survival of released fish. He recommended that more research should be conducted to investigate the link between welfare and fillet quality in commercial catches. Dr. Breen also introduced a new research project on Atlantic bluefin tuna (ABT, Thunnus thynnus) welfare in a rod and line fishery. In this project, his team will monitor various environmental, operational and animal-based metrics during capture, handling and slaughter to assess their effects on ABT welfare and quality, with the aim of further developing welfare-conscious capture and handling practices.

Presenter: Prof. Liuyi Huang, Ocean University of China.

Presentation Title: Current status of China’s capture fisheries and progress of Catch Welfare.

Prof. Huang introduced the current status of the Chinese capture fishery industry, particularly the challenges it faces now, including the declining fishery resource, the need for industry upgrading, incomplete research on eco-friendly fishing gear and methods, and the issue of lost and abandoned fishing gear. Though the attention and study on catch welfare are still lacking in China, Prof. Huang provided examples of welfare-relevant research from China, such as studies on fishing gear selectivity (e.g., [4,5,6,7,8,9,10,11,12,13,14,15,16,17] and surveys on discarded fishing gears [18]. He emphasized that catch welfare will be an important research area in the future, as improving catch welfare not only ensures national food supply and sustainable development of resources, but also guarantees food security and social stability.

Presenter: Prof. Lynne Sneddon, University of Gothenburg, Sweden.

Presentation Title: Welfare of decapod crustaceans: Evidence for pain.

Prof. Lynne Sneddon presented her team’s recent research on investigating welfare in crustaceans by investigating nociceptors and pathways to the central nervous system, exploring the use of pain-relieving drugs in preventing behavioural and physiological responses, and determining humane ways of killing crustaceans. Her research concluded that nociception and central nervous system processing do occur in the shore crab [19] and pain-relieving drugs reduce the behavioural responses to electric shock in Norway lobster. Investigation into humane methods of killing demonstrated that Norway lobster was rapidly killed using electric shock, but this was not effective in signal crayfish. She believed current evidence may drive changes in legislation, public opinion, and industry practices for decapods.

Presenter: Dr. Maria Cabrera, Researcher, Centre for Marine Research, Portugal.

Presentation Title: Impact of environmental abundance in aquaculture on aquatic animal welfare.

Dr. Maria Cabrera started her presentation by introducing the definition of environmental enrichment and the five basic types of environmental enrichment in fish farming, including sensorial, dietary, social, occupational, and physical. She then presented the recent research her team conducted on exploring the effects of structural enrichment for seabream broodstock on heart rate using internal bio-loggers, which showed that environmental enrichment can significantly reduce fish’s heart rate during stressful events. Her presentation concluded that environmental enrichment can benefit fish welfare by promoting natural behaviours, reducing stress, reducing malformation, improving fish health and promoting positive welfare.

2.3. Discussions

This seminar featured two structured and in-depth discussion sessions following the morning and afternoon presentations. These two sessions brought together key stakeholders from academia, industry, and certification bodies to discuss the current landscape, challenges, and opportunities in aquatic animal welfare. The morning discussion, moderated by Prof. Li Xian of Ocean University of China, was centered on the theme “Animal Welfare and Innovation in Aquaculture and Capture Fishery”, and the afternoon discussion, moderated by Prof. Lv Weiqing of Shanghai Ocean University and focused on “From Science to Practice: Translating Welfare Research Into Practical Solutions for Commercial Use—Opportunities and Challenges”. This section presents a summary of the discussion outcomes.

2.3.1. Current Challenges

A central focus of the discussions was the current challenges involved in advancing animal welfare through technological innovation and applying them to commercial operations. Dr. Hans van de Vis highlighted that machine calibration and monitoring, particularly for equipment used in fish stunning during slaughter, remain a significant bottleneck. Prof. Sonia Rey Planellas also emphasised the need for extensive debugging to ensure the accurate operation of the equipment in practice.

Dr. Tore Kristiansen pointed out the importance of accurate assessment of fish stress levels in the process of applying new technologies, with efficient machine stunning ideally performed when animals exhibit lower stress responses to uphold welfare standards and maintain product quality.

Professor Li Dapeng reflected on the challenges of applying behavioral research findings to commercial aquaculture operations. He stressed the need for more species-specific research that considers welfare from the fish’s perspective, avoiding anthropocentric interpretations, particularly within the diverse Chinese aquaculture context.

Dr. Maria Cabrera believed that the communication gap between academia and industry is another significant challenge when it comes to applying technological innovation to commercial practice. While significant scientific progress has been made, real-world implementation depends on closer cooperation between researchers and practitioners, so bridging this gap is essential to achieving meaningful welfare improvements for aquatic animals at scale.

Professor Lynne Sneddon emphasized that for welfare practices to be widely adopted, the industry must perceive a clear economic benefit. She noted that partnerships between scientists and industry can play a crucial role in addressing this challenge by providing information on how welfare improvements can be achieved cost-effectively. She also identified the lack of government support for small-scale farmers as an additional barrier to the adoption of welfare practices and engagement with certification bodies.

Mr. Guan Fufeng, Manager of Fishery and Refiner Technology BAADER Asia, on the other hand, stressed that successful technological innovation must be underpinned by a genuine and widespread understanding of fish welfare within the industry. Without this conceptual foundation, even the most advanced technologies may fail to deliver their intended benefits.

2.3.2. Opportunities

The discussants also exchanged their ideas on the potential opportunities for improving aquatic animal welfare through research and innovations.

Dr. Michael Breen brought attention to the relatively nascent field of welfare in capture fisheries. He suggested that experiences from aquaculture could inform practices for wild-caught species. Key research priorities and opportunities include investigating links between welfare and product quality or shelf life, and developing improved capture and slaughter methods to reduce stress and injury.

Dr. Zhao Dandan, Head of R&D at Guangzhou Chengyi Aquaculture Ltd., Guangzhou, China, emphasized that improving fish welfare—particularly in traditional pond-based systems—can also boost productivity. Key areas include enhancing water self-purification and developing precise feeding technologies suited for low-visibility environments. She also noted that better product quality and shelf life are major incentives for adopting welfare-focused innovations from the standpoint of industry.

Mr. Ola Frøvik, Farm Manager from Nordic Aqua Partners, Ningbo, China, emphasized that developing technologies to enhance farming conditions and humane transport and slaughter practices have been their priorities, not only to improve welfare outcomes but also to yield measurable productivity gains.

Mr. Changlin Ye, Farm Manager from ZeHui Aquaculture (GuangZe) Co., Ltd., Nanjing, China, one of the largest companies applying the Recirculating Aquaculture System (RAS) to farm Japanese and American eels, emphasized that fish welfare is central to their operational philosophy. The company formed ongoing collaborations with researchers to improve feed formulation, ensuring both nutritional adequacy and palatability, and he believes one big opportunity that they want to explore is the automated, humane grading systems to mitigate stress associated with manual sorting.

In the end, Dr. Jian Zhu proposed that fish welfare itself also represents a critical point of innovation in the processing of high-yield freshwater species in China. The adoption of mechanized and intelligent slaughter technologies designed with welfare principles can significantly reduce fish stress during processing, thereby improving food safety and product quality, which is requested by consumers.

2.3.3. The Role of the Market

The discussions also focus on a broader discussion on the market’s role in advancing welfare practices.

And here, the market is the main motivator for the industry to make changes.

Professor Huang Liuyi concluded by reflecting on the broader socio-cultural context. In contrast to Europe, consumer awareness of fish welfare in China remains limited, reducing the market-driven impetus for reform. This poses a significant barrier to the widespread adoption of higher welfare standards, despite growing academic and industry interest.

Ms. Wang Xin, Market Development Director of Global Seafood Alliance-China, addressed the economic challenges associated with welfare implementation. While producers often bear additional costs to improve animal welfare, consumer willingness to pay a premium remains limited. She highlighted the role of certification schemes in differentiating high-welfare products and delivering added market value.

Experts agreed that consumer education is essential in creating demand for welfare-conscious products. At the same time, striking a balance between production efficiency and animal welfare remains crucial to ensure both ethical integrity and economic viability.

2.4. Closing Remarks

Prof. Ye Zhangying, Chair of the seminar and faculty member of the College of Biosystems Engineering and Food Science at Zhejiang University, delivered the closing remarks for the seminar. He noted that the seminar represented a significant advancement in terms of participant diversity, including international experts, Chinese researchers, and industry representatives, as well as the scale of attendance and breadth of discussion topics. He expressed his sincere gratitude to all attendees for their active engagement and to the organizing team for their dedicated efforts. He emphasized that improving aquatic animal welfare is a shared responsibility, requiring coordinated action from governments, industry, scientists, the market, and the broader public. While producers hold a central role, he underscored the importance of recognizing that animal welfare and production efficiency are not mutually exclusive. He concluded by stressing the urgent need for scientifically rigorous research to inform welfare standards and guide responsible practices. Over time, he expressed confidence that these efforts will increasingly attract support and participation from both public authorities and society at large.

3. Conclusions and Future Directions

As the seafood industry sector continues to grow in scale and complexity, the development and implementation of science-based welfare approaches will be critical for ensuring sustainable and ethical seafood production. In this context, the convening of the Aquatic Animal Welfare Research and Practice Seminar represented a significant milestone. It yielded valuable outcomes and laid the groundwork for future interdisciplinary and cross-sector collaboration. It underscored the increasing prominence of aquatic animal welfare in both scientific research and industry practice, particularly within China, the world’s leading seafood producer. The seminar also illuminated the complex challenges involved in integrating animal welfare considerations into aquaculture and fisheries practices. Effectively addressing these challenges will require a coordinated strategy that combines technological innovation, empirical research, and policy development, alongside active engagement with industry stakeholders and efforts to raise consumer awareness. In the long term, grounding in scientific rigor and being guided by practical feasibility, sustained collaboration among scientists, policymakers, industry practitioners, and the broader public will be crucial for driving meaningful and enduring progress in aquatic animal welfare.

Moving forward, to further strengthen knowledge exchange and foster international collaboration, Zhejiang University and the Catch Welfare Platform jointly established the International Aquatic Animal Welfare Working Group, which held its kick-off meeting on the day following the seminar. The Working Group comprises 20 members representing 12 leading universities and research institutions from both China and abroad, along with four industry representatives. Through collaboration with academic and industry stakeholders worldwide, the group aims to advance scientific research and facilitate critical discussions on the key challenges and emerging issues in global aquatic animal welfare.