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- Bastardie, Francois, et al.
(författare)
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Reducing the Fuel Use Intensity of Fisheries : Through Efficient Fishing Techniques and Recovered Fish Stocks
- 2022
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Ingår i: Frontiers in Marine Science. - : Frontiers Media S.A.. - 2296-7745. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the drivers of greenhouse gas emissions in food production systems is becoming urgent. For wild capture fisheries, fuel use during the fishing phase generally dominates emissions and is highly variable between fisheries. Fuel use is also essential for the economy of the fisheries, but fuel-intensive fisheries can still be profitable due to fuel subsidies, in particular, if the target species is of high value. Developing an innovative bottom-up approach based on detailed catch and spatial fishing effort data, in the absence of direct fuel data, we analysed the fuel use intensity (fuel use per kg landed) and economic efficiency (landing value per litre fuel used) of Danish capture fisheries for the period 2005-2019. An overall decline in fishing effort did not significantly affect the overall fuel use intensity and efficiency, which was stable for most of the fleet segments and marine species. Robust differences in fuel use intensity among individual fisheries, reflected differential spatial accessibility and vulnerability of target species to fishing. In addition, different fishing techniques targeting the same set of species showed differences in fuel use per unit landed. Danish seining and gillnets had a lower fuel use intensity and higher economic efficiency than demersal trawling; and purse seining than pelagic trawling. The variability between stocks and fleets also indicates that there is generally potential for improvement in overall efficiency from improved stock status. Short-term management actions to promote the best available fuel-efficient fishing techniques combined with additional long-term actions to secure the recovery of stocks have the potential to reduce fishery greenhouse gas emissions. Sustainable fisheries and normative environmental management are crucial to developing incentives towards reducing fuel use whenever the fishing sector industry and science work jointly at implementing solutions, as incentives for the industry to reduce fuel use are limited as long as the fishing activity is profitable. Copyright © 2022 Bastardie, Hornborg, Ziegler, Gislason and Eigaard.
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| 2. |
- Hornborg, Sara, et al.
(författare)
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Greenhouse gas emissions of seafood from Danish capture fisheries in the Skagerrak, Kattegat, and western Baltic
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Interest in finding sustainable diets is increasing where more attention has been paid to the role of seafoods in recent years. Danish fisheries’ producer organisations are interested in better understanding the carbon footprint and nutritional content of different species caught in Danish fisheries and how they compare to other types of animal-source food. The aim of this report is to place a selection of seafood products from Danish capture fisheries in a sustainable nutrition context. This is done by quantifying their greenhouse gas emissions, inferred from fishing effort, as well as nutritional content and relate findings to previous estimates of other common animal-source foods (farmed salmon, chicken, pork and beef). Furthermore, attempts to identify important drivers and improvement potentials are made. It is found that in terms of nutritional value, fatty fish (herring and farmed salmon) have a higher combined nutrient density than other foods included. Overall, herring and plaice caught in Danish fisheries in the Skagerrak, Kattegat and western Baltic are animal-source foods with lower greenhouse gas emissions than pork, beef, chicken, and farmed salmon. The same results are found for cod compared to pork and beef. Variability within and between gears, fishing areas and over time is however found, indicating improvement potentials. In the Skagerrak and Kattegat, shifting from demersal trawling to Danish seine/other gear types would lower fisheries greenhouse gas emissions considerably, while this potential is smaller in the western Baltic Sea. This partly reflects different targeting patterns, where cod is the main target species in the western Baltic Sea, while it is more a by-catch in crustacean fisheries in the other fishing areas. When results are compared with other fisheries targeting the same species, Danish plaice fisheries are associated with considerably lower fuel use relative to other fisheries for plaice. Results for Danish herring and cod vary depending on fishery, with some fisheries being less efficient than found elsewhere. The outcome for Danish fisheries is in part reflecting the different gears used but could also indicate different stock status, in particular for cod, and different methodological approaches. More detailed analysis, with collection of actual fuel use data for these fisheries instead of using modelled data, would be of interest to allow for further understanding of drivers as well as validation of results.
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| 3. |
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| 4. |
- Nielsen, Rasmus J., et al.
(författare)
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Integrated ecological–economic fisheries models—Evaluation, review and challenges for implementation
- 2018
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Ingår i: Fish and Fisheries. - : Wiley. - 1467-2960 .- 1467-2979. ; 19:1, s. 1-29
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Forskningsöversikt (refereegranskat)abstract
- Marine ecosystems evolve under many interconnected and area-specific pressures. To fulfil society's intensifying and diversifying needs while ensuring ecologically sustainable development, more effective marine spatial planning and broader-scope management of marine resources is necessary. Integrated ecological–economic fisheries models (IEEFMs) of marine systems are needed to evaluate impacts and sustainability of potential management actions and understand, and anticipate ecological, economic and social dynamics at a range of scales from local to national and regional. To make these models most effective, it is important to determine how model characteristics and methods of communicating results influence the model implementation, the nature of the advice that can be provided and the impact on decisions taken by managers. This article presents a global review and comparative evaluation of 35 IEEFMs applied to marine fisheries and marine ecosystem resources to identify the characteristics that determine their usefulness, effectiveness and implementation. The focus is on fully integrated models that allow for feedbacks between ecological and human processes although not all the models reviewed achieve that. Modellers must invest more time to make models user friendly and to participate in management fora where models and model results can be explained and discussed. Such involvement is beneficial to all parties, leading to improvement of models and more effective implementation of advice, but demands substantial resources which must be built into the governance process. It takes time to develop effective processes for using IEEFMs requiring a long-term commitment to integrating multidisciplinary modelling advice into management decision-making.
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| 5. |
- van Beest, Floris M, et al.
(författare)
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Classifying grey seal behaviour in relation to environmental variability and commercial fishing activity -a multivariate hidden Markov model
- 2019
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Classifying movement behaviour of marine predators in relation to anthropogenic activity and environmental conditions is important to guide marine conservation. We studied the relationship between grey seal (Halichoerus grypus) behaviour and environmental variability in the southwestern Baltic Sea where seal-fishery conflicts are increasing. We used multiple environmental covariates and proximity to active fishing nets within a multivariate hidden Markov model (HMM) to quantify changes in movement behaviour of grey seals while at sea. Dive depth, dive duration, surface duration, horizontal displacement, and turning angle were used to identify travelling, resting and foraging states. The likelihood of seals foraging increased in deeper, colder, more saline waters, which are sites with increased primary productivity and possibly prey densities. Proximity to active fishing net also had a pronounced effect on state occupancy. The probability of seals foraging was highest <5 km from active fishing nets (51%) and decreased as distance to nets increased. However, seals used sites <5 km from active fishing nets only 3% of their time at sea highlighting an important temporal dimension in seal-fishery interactions. By coupling high-resolution oceanographic, fisheries, and grey seal movement data, our study provides a scientific basis for designing management strategies that satisfy ecological and socioeconomic demands on marine ecosystems.
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