Number of attempts have been made to cryopreserve fish and shellfish gametes. Success has been achieved to establish only sperm banks in case of some commercially important fish. In shellfish, also particularly in shrimps, though the sperm cryopreservation was successful, no attempts were made to develop sperm banks. As far as cryopreservation of egg and embryos of fish and shellfish is concerned, less research efforts were made with limited success. Number of reasons have been given for the failure of egg/embryo cryopreservation and the main barriers speculated are low membrane permeability in the eggs, the large yolk mass of the oocyte, and the presence of compartments in early developing embryos. These factors result in ice crystal formation during the freezing process. In addition, the oocytes and embryos are prone to chilling injuries unrelated to ice crystal damage. There are number of other problems reported by several researchers in the egg/embryo cryobanking protocols which are elaborately discussed in the present paper. There is an urgent need to develop a viable cryobanking technology for fish egg/embryos to enhance fish production in captive condition. Attempts to cryopreserve larvae of aquatic animals is another challenge occurring in the recent past. The aim of the present review is to collect comprehensive information on the efforts so far made on fish and shellfish egg and embryo cryobanking; and to assess the challenges in the development of viable technology and plan for future research for making this technology viable and cost effective.
Aquaculture, Seafood, and Food Security
Alongside government driven management initiatives to achieve sustainable fisheries management, there remains a role for market-based mechanisms to improve fisheries outcomes. Market-based mechanisms are intended to create positive economic incentives that improve the status and management of fisheries. Research to understand consumer demand for certified fish is central but needs to be mirrored by supply side understanding including why fisheries decide to gain or retain certification and the impact of certification on them and other stakeholders involved. We apply semi-structured interviews in seven different Marine Stewardship Council (MSC) certified fisheries that operate in (or from) Western Australia with the aim of better understanding fisheries sector participation in certification schemes (the supply side) and the impacts and unintended benefits and costs of certification. We find that any positive economic impacts of certification were only realised in a limited number of MSC fisheries in Western Australia, which may be explained by the fact that only a small proportion of Western Australian state-managed fisheries are sold with the MSC label and ex-vessel or consumer market price premiums are therefore mostly not obtained. Positive impacts of certification in these Western Australian fisheries are more of a social and institutional nature, for example, greater social acceptability and increased efficiency in the governance process respectively. However, opinion is divided on whether the combined non-monetary and monetary benefits outweigh the costs.
The direct and indirect impact of fish farms, shellfish aquaculture, and extensive forms of aquaculture such as seeding of juvenile sea urchins, on macrophytes (seaweeds and seagrasses), is reviewed in Mediterranean benthic ecosystems. Fish farms constitute a source of organic matter and nutrients (food and fecal pellets) that causes the extirpation of Posidonia oceanica seagrass meadows beneath and near to farm facilities. In addition to direct effects, the nitrogen enrichment of macrophytes tissues increases the grazing pressure by herbivorous fishes and sea urchins. In some cases, the impact can continue to increase several years after the cessation of farming activities. Natural restoration of extirpated seagrass meadows is generally unlikely at the human time scale. Shellfish aquaculture is the cause of the main flow of introduced macrophytes in the Mediterranean; the main vector is the importation of oyster spat from Japan and Korea. North-eastern Pacific seaweeds are now the dominant biotic component of some Mediterranean lagoons (e.g., Thau, Mar Piccolo, and Venice lagoons). In addition to direct effects, mussel aquaculture can constitute a source of larvae that flow with currents, the adults of which can overwhelm seaweed forests (e.g., Carpodesmia mediterranea). Shellfish aquaculture is also a source of fecal pellets, resulting in changes in bottom macrophytes, and a vector of diseases of metazoans, the extirpation of which may change the functioning of recipient macrophyte ecosystems. The edible sea urchin Paracentrotus lividus is sometimes erroneously considered as in decline due to over-harvesting. However, its abundance in the second half of the 20th century was probably a consequence of human impact (overfishing of its predatory fish, organic pollution. This man-induced proliferation resulted in the extirpation of seaweed forests (e.g., Carpodesmia spp., Treptacantha spp. – formerly Cystoseira spp. – Sargassum spp.; many species are endemic), which play a key role in Mediterranean coastal ecosystems. Therefore, the attempts to restore sea urchin abundance, via seeding of juveniles from hatcheries, has further artificialized the habitats rather than contributing to the restoration of natural ecosystems. Good practices guidelines are proposed aimed at minimizing the impact of aquaculture on macrophytes.
Seafood mislabelling is a global issue that affects consumers, target species, and the ability to manage fisheries. Due to their high demand and value, groupers (Epinephelinae spp.) are frequent targets for fraudulent substitution on the world's major seafood markets. Yet, little is known on the prevalence of grouper mislabelling in the Wider Caribbean Region. We conducted the first ‘grouper’ authentication survey in the Turks and Caicos Islands (TCI), a luxury tourist destination where the locally caught but critically endangered Nassau grouper (Epinephelus striatus) features prominently on menus. DNA barcoding was used to assess mislabelling of market samples and simultaneously to gauge compliance with the Nassau grouper closed season. Our genetic analyses did not detect banned Nassau grouper, but only 18% of samples from restaurants and stores were confirmed as Epinephelinae (i.e. groupers), and 96% were mislabelled in some way. Substitutes for grouper mostly comprised freshwater catfish (Pangasianodon hypophthalmus; 57% of samples) and snappers (Lutjanidae; 25%), whereas samples sold as ‘local grouper’ were from Indo-Pacific or Asian inland waters. Only 22% of samples were matched to species found locally, all being cubera snapper (Lutjanus cyanopterus). Our study suggests that (i) mislabelling is motivated predominantly by financial incentives and/or driven by low supplies of groupers, (ii) local fishers are not the main source of mislabelled grouper into the supply chain, and (iii) the primary victims are consumers, fishing communities, and ultimately fragile fish stocks. Our findings can be used to help improve transparency, traceability and accountability in local seafood supply chains.
Aquaculture has become the fastest-growing sector of the food industry worldwide. The increase of intensive aquaculture practices, however, has been raising global concern about economic and social impacts, but mostly due to the associated potential environmental impacts. The aim of this report is to make a preliminary assessment of the impact of an intensive sea bass aquaculture (Dicentrarchus labrax, L. 1758) on surrounding coastal waters. The aquaculture site is located at the SW Iberian coast (Sines, Portugal), having 16 cages, each holding approximately 150,000 specimens at different stages of growth. We present a spatial and temporal description of environmental physical, chemical, and biological parameters taken in the course of four monitoring campaigns conducted between June 2018 and April 2019. All monitored parameters, except phosphate concentration in October only at one sampling station, showed values within the desirable ranges for marine finfish production and the natural range of Portuguese coastal waters. So far, results do not reveal any detrimental impact of the production units on local water quality, although more research is needed. The preliminary findings suggest that the lack of stress on the receiving waters may be attributed to the hydrodynamic regime in the production area, the feeding strategy, and the dimension of the production.
Voluntary Sustainability Standards and ecolabels are market-based mechanisms used to encourage producers and consumers toward environmental sustainability. The Marine Stewardship Council (MSC) aims to improve ocean health and promote a sustainable seafood market. There is growing interest in the program’s impacts (direct and indirect) from changes to fisheries management and consumer awareness to market access and the reputation of fisheries. To better understand what is known about the program’s impacts and the quality of evidence available, this map collates and describes articles on the environmental, social, institutional and economic effects of the MSC, identifying the methods used to determine impacts, and highlighting knowledge gaps and clusters.
Following an a priori protocol, systematic searches of peer-reviewed literature were conducted in Web of Science, SCOPUS and AGRIS. Grey literature was gathered from Google Scholar, Microsoft Academic, and three subject-specific websites. A total of 771 articles were retrieved, 271 of which were screened at full-text. 28 articles met all inclusion criteria and a further 37 met all the criteria but did not have a comparator. Additionally, 108 articles that describe the MSC but do not investigate its impacts (thus failing on ‘comparator’ and ‘outcome’ inclusion criteria) were included in the narrative report. This provides an overview of MSC topics that are of general interest to researchers in comparison to articles that investigate MSC’s impact.
Evidence of the impact of MSC certification fall in the following topic categories: economic (38%), environmental (25%), governance (29%) and social (8%). These articles documented diverse outcomes related to MSC certification. The most common are price premiums, market access, changes in stock health, ecosystem impacts and fisheries management changes. A key knowledge gap are articles on the effects of the MSC’s Chain of Custody Standard and its effects on the supply chain. Generally, literature focused on European and North American fisheries with little focus on fisheries situated in lower-income countries.
Research interest in the MSC has grown over the last two decades, however, little research uses study designs and evidence that can robustly detect or attribute change to the MSC. Greater focus on conducting robust quasi-experimental designs would help to better understand the program effects. Comparing areas of interest in the general literature (which, for example, shows greater focus on the governance aspects of the programme than found in literature using comparators) suggests that this is partly due to lack of resources, data access and the challenge of obtaining counterfactuals. Nevertheless, some topics were absent in all areas, such as the social and economic dynamics that link harvesters and supply chain actors. It is important to fill the identified knowledge gaps as the behaviours of certified harvesters, supply chain actors and other stakeholders are the key through which the public influence sustainability, market inclusion/exclusion operates, and inequality is generated. Understanding these processes can have wider relevance in the field, informing the design of other sustainability interventions.
Aquaculture is among the industries growing at the fastest rate in the world. This industry has been recognized to play a critical role in food production for a continuously expanding world population. However, despite various technological innovations and improvements in production techniques, this sector is still associated with misperceptions and negative opinions hampering its implementation and wide consumption of its products. The integrated multi-trophic aquaculture (IMTA) concept was developed as a way to increase the sustainability of intensive aquaculture systems, using an ecosystem-based approach. In this study, following this sustainable aquaculture concept, a closed recirculation IMTA system, at laboratorial scale, was developed and tested with the simultaneous production of fish, sea urchin and seaweed for 70 days. Based on this proof of concept, a hands-on experimental activity was developed to teach and communicate recent scientific advances in environmental sustainability and value of aquaculture products to young students and the general public. This experimental activity was tested and evaluated with students (n = 60) of basic and high-school (secondary) learning cycles. A quantitative assessment was carried out through a short questionnaire provided to the students before and after the experimental activity. After the experimental activity, a qualitative assessment was also performed through questions expressed without preconceived categories or hypotheses. Results indicated that the overall frequency of students who consider the ocean to be “very important” and “extremely important” increased from 68 to 81% after performing the experimental activity. Moreover, the percentages of correct answers to the questions related to IMTA concepts also increased significantly after the experimental activity. In the discussion of the experimental activity results, the students stated that they appreciated the opportunity to develop a hands-on experimental activity, which allowed them to increase their knowledge and obtain information on aquaculture and the quality of its products.
Norway, the world's leader in the production and export of farmed Atlantic salmon, recently established a new management regime with a view to promoting substantial long-term growth in the industry. The government stated plainly, however, that the industry would have to be environmentally sustainable. The determination would be made through the use of indicators, but only one indicator would go into effect as the new regime was instituted: the amount of salmon lice (Lepeophtheirus salmonis) on wild salmon. This paper asks why this one, lone variable was selected. Using policy documents, the draft white paper outlining the new management plan sent out for comment by the government and the responses made by key stakeholders to the draft plan, this paper argues that the selection of this one indicator was overdetermined. Many factors contributed to the selection, including the government's fundamental decision to expand production, the momentum of Norwegian policy development, how the draft white paper defined and discussed environmental sustainability, the criteria established for acceptable indicators and the specifics of the proposed management plan. These had a political effect: For these reasons and more, no solid block of stakeholders emerged to press unambiguously for additional indicators at the start of the scheme, merited or not. This study also demonstrates the difficulties presented by a public debate on a management plan such as this.
In Norway, the world's largest salmon-producing country, reducing sea-lice levels in fish farms has been an overarching goal of government policy since 2013. However, industry innovation has not yet succeeded in significantly reducing the sea lice problem.
We identify two main types of radical environmental innovation that could potentially resolve the sea-lice problem: in-shore closed-cage production technology, and a genetically lice-resistant salmon. Furthermore, we provide an analytical framework that shows how radical environmental innovations with a “public good” character are least likely to receive private R&D funds. This leads us to conclude that neither in-shore closed cage technology nor targeted breeding towards lice-resistance will succeed in the market unless backed by targeted government intervention.
Closer examination shows that these two types of innovation have been less prioritized, if at all, in recent policy interventions. First, the government has geared most of financial support towards relieving the risk of investment in offshore innovation projects, although inshore projects might be better suited for accommodating public and environmental needs. Second, this study underscores the need and potential for stimulating sustainable innovation through the genetic route—a point overlooked in Norway's current policy mix.
The seafood market is highly globalised with a growing demand for seafood and fish products worldwide. The capacity of wild fisheries is limited and therefore aquaculture is fast becoming the most stable source of seafood to meet increasing demand. Subsequently, the perceived environmental risk of fin-fish aquaculture has been the focus of substantial environmental campaigning, media and public scrutiny around the world. This paper places localised tensions regarding the environmental impacts of salmon aquaculture within transnational environmental sustainability debates concerning seafood production and vice-versa, with a focus on the Australia-Asia region. The results contribute to understanding the interpretation and communication of environmental sustainability of seafood through international supply chains and to audiences at different spatial scales. The paper draws particularly on the case of salmon aquaculture in Tasmania, Australia’s southern island state. It highlights mechanisms, such as certification, for which information flows transnationally regarding the environmental sustainability of seafood production, the resultant transnational and local public sphere and the implications for local discourse, market access, governance and certification of seafood production.