| 1. |
- Gephart, Jessica A., et al.
(författare)
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The 'seafood gap' in the food-water nexus literature-issues surrounding freshwater use in seafood production chains
- 2017
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Ingår i: Advances in Water Resources. - : Elsevier BV. - 0309-1708 .- 1872-9657. ; 110, s. 505-514
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Tidskriftsartikel (refereegranskat)abstract
- Freshwater use for food production is projected to increase substantially in the coming decades with population growth, changing demographics, and shifting diets. Ensuring joint food-water security has prompted efforts to quantify freshwater use for different food products and production methods. However, few analyses quantify freshwater use for seafood production, and those that do use inconsistent water accounting. This inhibits water use comparisons among seafood products or between seafood and agricultural/livestock products. This 'seafood gap' in the food-water nexus literature will become increasingly problematic as seafood consumption is growing globally and aquaculture is one of the fastest growing animal food sectors in the world. Therefore, the present study 1) reviews freshwater use concepts as they relate to seafood production; 2) provides three cases to highlight the particular water use concerns for aquaculture, and; 3) outlines future directions to integrate seafood into the broader food-water nexus discussion. By revisiting water use concepts through a focus on seafood production systems, we highlight the key water use processes that should be considered for seafood production and offer a fresh perspective on the analysis of freshwater use in food systems more broadly. This is an open access article under the CC BY-NC-ND license.
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| 2. |
- Beveridge, M. C. M., et al.
(författare)
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Meeting the food and nutrition needs of the poor : the role of fish and the opportunities and challenges emerging from the rise of aquaculture
- 2013
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Ingår i: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 83:4, s. 1067-1084
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Tidskriftsartikel (refereegranskat)abstract
- People who are food and nutrition insecure largely reside in Asia and Sub-Saharan Africa and for many, fish represents a rich source of protein, micronutrients and essential fatty acids. The contribution of fish to household food and nutrition security depends upon availability, access and cultural and personal preferences. Access is largely determined by location, seasonality and price but at the individual level it also depends upon a person's physiological and health status and how fish is prepared, cooked and shared among household members. The sustained and rapid expansion of aquaculture over the past 30years has resulted in >40% of all fish now consumed being derived from farming. While aquaculture produce increasingly features in the diets of many Asians, it is much less apparent among those living in Sub-Saharan Africa. Here, per capita fish consumption has grown little and despite the apparently strong markets and adequate biophysical conditions, aquaculture has yet to develop. The contribution of aquaculture to food and nutrition security is not only just an issue of where aquaculture occurs but also of what is being produced and how and whether the produce is as accessible as that from capture fisheries. The range of fish species produced by an increasingly globalized aquaculture industry differs from that derived from capture fisheries. Farmed fishes are also different in terms of their nutrient content, a result of the species being grown and of rearing methods. Farmed fish price affects access by poor consumers while the size at which fish is harvested influences both access and use. This paper explores these issues with particular reference to Asia and Africa and the technical and policy innovations needed to ensure that fish farming is able to fulfil its potential to meet the global population's food and nutrition needs.
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| 3. |
- Cottrell, Richard S., et al.
(författare)
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Time to rethink trophic levels in aquaculture policy
- 2021
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Ingår i: Reviews in Aquaculture. - : Wiley. - 1753-5123 .- 1753-5131. ; 13:3, s. 1583-1593
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Tidskriftsartikel (refereegranskat)abstract
- Aquaculture policy often promotes production of low-trophic level species for sustainable industry growth. Yet, the application of the trophic level concept to aquaculture is complex, and its value for assessing sustainability is further complicated by continual reformulation of feeds. The majority of fed farmed fish and invertebrate species are produced using human-made compound feeds that can differ markedly from the diet of the same species in the wild and continue to change in composition. Using data on aquaculture feeds, we show that technical advances have substantially decreased the mean effective trophic level of farmed species, such as salmon (mean TL = 3.48 to 2.42) and tilapia (2.32 to 2.06), from 1995 to 2015. As farmed species diverge in effective trophic level from their wild counterparts, they are coalescing at a similar effective trophic level due to standardisation of feeds. This pattern blurs the interpretation of trophic level in aquaculture because it can no longer be viewed as a trait of the farmed species, but rather is a dynamic feature of the production system. Guidance based on wild trophic position or historical resource use is therefore misleading. Effective aquaculture policy needs to avoid overly simplistic sustainability indicators such as trophic level. Instead, employing empirically derived metrics based on the specific farmed properties of species groups, management techniques and advances in feed formulation will be crucial for achieving truly sustainable options for farmed seafood.
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| 4. |
- Gephart, Jessica, et al.
(författare)
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Environmental performance of blue foods
- 2021
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Ingår i: Nature. - : Nature Research. - 0028-0836 .- 1476-4687. ; 597:7876, s. 360-365
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Tidskriftsartikel (refereegranskat)abstract
- Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies3,4 relative to the vast diversity of production5. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets. © 2021, The Author(s)
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| 5. |
- Holmerin, Isak, et al.
(författare)
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Uptake and transfer of five trace metals from clam to oxygen-deprived fish in a marine benthic pathway
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- As a result of eutrophication and climate change, marine benthic areas around the world are suffering from expanding oxygen minimum zones (OMZs) where hypoxia has become a real threat to local ecosystems. Coastal and estuarine areas are especially prone to develop OMZs due to high nutrient loading. These areas are also preferred sites for nuclear power plants (NPPs), which continuously provide nearby watersheds and coastal areas with radioactive effluents. However, the effects of hypoxia on the trophic transfer of radionuclides is poorly documented. Studied here is the uptake in the bivalve Ruditapes philippinarum of five radioactive trace metals (54Mn, 57Co, 65Zn, 110mAg, and 134Cs), common in intentional or accidental effluents from nuclear power plants, and their subsequent transfer to the benthic teleost Pomatoschistus minutus living in oxygen-deprived conditions simulating mild or severe hypoxia. In R. philippinarum, the radionuclide uptake was dominated by 65Zn and 110mAg with a comparably low uptake of 54Mn. This was not reflected in the radionuclide transfer after feeding R. philippinarum to P. minutus, which predominately incorporated 54Mn and 65Zn, indicating a species specific preference for certain trace metals. There was a tendency for higher retention of radionuclides in P. minutus suffering from severe hypoxia. A possible explanation is the increased stress caused by the low oxygen levels. Longer retention times of radionuclides would cause a longer radiation exposure, possibly affecting fish living in OMZ negatively.
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| 6. |
- McNicholl, Conall, et al.
(författare)
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Deoxygenation reduces growth rates and increases assimilation of essential trace metals in gilthead seabream (Sparus aurata)
- 2021
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424. ; 288
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Tidskriftsartikel (refereegranskat)abstract
- The widespread decline in oceanic dissolved oxygen (DO), known as deoxygenation, is a threat to many marine ecosystems, and fish are considered one of the more vulnerable marine organisms. While food intake and growth rates in some fish can be reduced under hypoxic conditions (DO ~ 60 μmol kg−1), the dietary transfer of essential metals remains unclear. In this context, we investigated the influence of DO on the dietary acquisition of two essential metals (Zn and Mn) in the commercially important gilthead seabream (Sparus aurata) using radiotracer techniques. Fish were exposed to variable DO conditions (normoxia 100% DO, mild-hypoxia 60% DO, and hypoxia 30% DO), and fed a single radiolabeled food ration containing known activities of 54Mn and 65Zn. Depuration and assimilation mechanisms under these conditions were followed for 19 d. Based on whole body activity after the radio-feeding, food consumption tended to decrease with decreasing oxygen, which likely caused the significantly reduced growth (- 25%) observed at 30% DO after 19 d. While there was an apparent reduction in food consumption with decreasing DO, there was also significantly higher essential metal assimilation with hypoxic conditions. The proportion of 65Zn remaining was significantly higher (~60%) at both low DO levels after 24 h and 19 d while 54Mn was only significantly higher (27%) at the lowest DO after 19 d, revealing element specific effects. These results suggest that under hypoxic conditions, stressed teleost fish may allocate energy away from growth and towards other strategic processes that involve assimilation of essential metals.
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| 7. |
- Merrie, Andrew, et al.
(författare)
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An ocean of surprises - Trends in human use, unexpected dynamics and governance challenges in areas beyond national jurisdiction
- 2014
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Ingår i: Global Environmental Change. - : Elsevier BV. - 0959-3780 .- 1872-9495. ; 27, s. 19-31
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Tidskriftsartikel (refereegranskat)abstract
- The expanse of ocean which makes up all marine areas beyond national jurisdiction has been characterized as the last frontier of exploitation on the planet, a figurative final Wild West. Existing users of areas beyond national jurisdiction, with the exception of fisheries, currently have a limited footprint there as a consequence, in part, of substantial hurdles in technological development that need to be overcome before many resources can be extracted at a commercially viable scale. However, we argue surprise shifts perpetuated by both established and emerging users could lead to an expansion in actors taking opportunities to chase lucrative resources that they are currently constrained from exploiting. Rapid development could also lead to a crowded ocean due to the multiplication of users which could present a problem given the current lack of a unified institutional framework for governance connecting the different user groups. Here, we have collated trends in human use of areas beyond national jurisdiction and offer a framework for, and examples of, unexpected dynamics relevant to living and non-living marine resources. Such an approach is necessary in order to begin to mobilize an adequate governance response to changing conditions and uses of areas beyond national jurisdiction. This governance response must be able to govern established or potential users, be flexible and adaptive in response to unexpected and unpredictable dynamics and be able to transform in the face of unpredictable future uses of this vast area. Here we present a set of institutional design principles as a first tentative step in this direction.
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| 8. |
- Merrie, Andrew, 1982-, et al.
(författare)
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Radical futures for global fisheries : An imaginative narrative scenarios approach
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Scenarios are important tools in developing capacity for dealing with the unknown and unpredictable, as well as the unlikely but possible. A range of scientific methods for developing scenarios is available, but we argue that they have limited capacity to investigate complex social-ecological futures. We contend that for most scientific scenarios 1) non-linear change is rarely incorporated and that 2) in attempting to engage with complexity they often fail to interest an audience outside of academia. This manuscript intends to address these two concerns, by drawing on narrative approaches to scenarios and applying the method of Science Fiction Prototyping. Using a rich and empirical scientific background on existing and emerging trends in marine natural resource use and dynamics, we develop four ‘radical’ futures for global fisheries. They are written for a wide audience and each was carefully designed to incorporate and extrapolate from existing environmental, technological, social and economic trends. We argue that Science Fiction Prototyping can complement existing methods for developing scenarios and can assist scientists in developing a holistic understanding of complex systems dynamics. This approach holds promise for making scenarios more accessible and interesting to non-academics and thus more useful in discussion on policy and governance questions in marine fisheries.
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| 9. |
- Merrie, Andrew, et al.
(författare)
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Radical ocean futures-scenario development using science fiction prototyping
- 2018
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Ingår i: Futures. - : Elsevier BV. - 0016-3287 .- 1873-6378. ; 95, s. 22-32
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Tidskriftsartikel (refereegranskat)abstract
- Scenarios can help individuals, communities, corporations and nations to develop a capacity for dealing with the unknown and unpredictable, or the unlikely but possible. A range of scientific methods for developing scenarios is available, but we argue that they have limited capacity to investigate complex social-ecological futures because: 1) non-linear change is rarely incorporated and: 2) they rarely involve co-evolutionary dynamics of integrated social-ecological systems. This manuscript intends to address these two concerns by applying the method of science fiction prototyping to developing scenarios for the future of global fisheries in a changing global ocean. We used an empirically informed background on existing and emerging trends in marine natural resource use and dynamics to develop four 'radical ocean futures,' incorporating and extrapolating from existing environmental, technological, social and economic trends. We argue that the distinctive method as applied here can complement existing scenario methodologies and assist scientists in developing a holistic understanding of complex systems dynamics. The approach holds promise for making scenarios more accessible and interesting to non-academics and can be useful for developing proactive governance mechanisms.
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| 10. |
- Metian, Marc, et al.
(författare)
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Farming of Bluefin Tuna-Reconsidering Global Estimates and Sustainability Concerns
- 2014
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Ingår i: Reviews in Fisheries Science & Aquaculture. - : Informa UK Limited. - 2330-8249 .- 2330-8257. ; 22:3, s. 184-192
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Tidskriftsartikel (refereegranskat)abstract
- Increased global demand for bluefin tuna has triggered unsustainable fishing and many wild stocks have seen dramatic declines. Improved fisheries governance is now slowly stabilizing many stocks and recently bluefin aquaculture has emerged as an economic alternative route for supplying the market. Most of captured bluefin tuna directly enters the global seafood market, but an increasing part of catches are destined to aquaculture (17-37%) as bluefin aquaculture almost exclusively depends on wild specimens for stocking. Farming is mainly being performed in the Mediterranean region, Mexico, Australia, and Japan. Few studies have focused on the global importance and future role of bluefin aquaculture and there are confounding uncertainties related to production volumes and trends. This study provides an overview of global bluefin tuna aquaculture and identifies its direct and indirect interactions with wild fish stocks, outlines some of the challenges for future expansion as well as pointing out significant mismatch of production statistics.
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