| 1. |
- Lunneryd, Sven Gunnar, et al.
(författare)
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A large-mesh salmon trap: a way of mitigating seal impact on a coastal fishery
- 2003
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Ingår i: ICES Journal of Marine Science. - : Oxford Journals. - 1054-3139 .- 1095-9289. ; 60:6, s. 1194-1199
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Tidskriftsartikel (refereegranskat)abstract
- A new design for a salmon trap aimed at minimizing damage to catch and gear caused by grey seals was tested. The traditional trap design used in the northern Baltic permits an efficient hunting strategy by seals, whereby chased fish entangle themselves in the side panels and can then easily be taken, with associated damage to the net. The side panels of the test trap (excluding the fish chamber) are made of large-mesh (400 mm) netting compared to ≤200 mm in traditional traps. This should allow seal-chased and panicking salmon to pass through, while less stressed individuals should still be guided efficiently towards the fish chamber. Trials with the two trap types were performed at the mouth of the river Indal (northern Sweden) in a comparative test programme. Catches of salmon and trout in the test trap were larger than in the standard trap. We estimated that 65% of the potential catch was lost in the standard trap owing to seal predation, while escape rate through the large meshes in the test trap was 52%. The standard trap had a total of 269 holes owing to seal damage, while only six holes were found in the test trap. Seal activity in and around the standard trap was up to 16 times higher compared with the test trap and decreased considerably during the following year when only large-meshed traps were used in the area. We suggest that seals are difficult to deter from fishing gear as long as they get a reward in terms of food and propose that a strategy that deprives seals of a reward will make the gear uninteresting to them and may have long-term mitigation effects.
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| 2. |
- Alexander, Karen A., et al.
(författare)
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Investigating the recent decline in gadoid stocks in the west of Scotland shelf ecosystem using a foodweb model
- 2015
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 72:2, s. 436-449
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Tidskriftsartikel (refereegranskat)abstract
- Abundance and biomass of cod, haddock, and whiting in the waters off of the west coast of Scotland (wcoS) have undergone large changes in recent years, most notably a recent decline. These three species contribute a considerable part of Scottish demersal landings from this area and as such it is important to understand why these stocks are behaving the way they are. A number of explanations for the decline have been proposed, including: seal predation, pressure from Nephrops trawls, and fishing pressure more generally. We used an ecosystem model of the wcoS continental shelf (<200 m depth) to investigate whether these proposed explanations for declining gadoid stocks are feasible. Results suggest that the rise in the grey seal population over recent years has not led to the decline in gadoid stocks; there is insufficient bycatch by the Nephrops fleet to have a large impact on gadoid stocks; however, fishing, as a key driver of the west of Scotland shelf ecosystem, has impacted stocks and by decreasing fishing levels to maximum sustainable yield cod biomass may increase slightly though not returning to previous levels. Although this means we are little further forward in understanding the cause of recent gadoid declines in the area, the development of this model has enabled us to further our knowledge and understanding of aspects of trophic structure and the impacts of fishing on the wcoS.
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| 3. |
- Andersen, K. H., et al.
(författare)
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How community ecology links natural mortality, growth, and production of fish populations
- 2009
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1095-9289 .- 1054-3139. ; 66:9, s. 1978-1984
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Tidskriftsartikel (refereegranskat)abstract
- Andersen, K. H., Farnsworth, K. D., Pedersen, M., Gislason, H., and Beyer, J. E. 2009. How community ecology links natural mortality, growth, and production of fish populations. - ICES Journal of Marine Science, 66: 1978-1984.
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| 4. |
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| 5. |
- Arias, Anna, et al.
(författare)
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Trophic interactions and diel feeding rhythms of microzooplankton in a productive Swedish Fjord
- 2020
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 77:7-8, s. 2718-28
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Tidskriftsartikel (refereegranskat)abstract
- Microzooplankton play a pivotal role in the energy transfer between lower and upper trophic levels in marine planktonic food webs. While laboratory data suggest that microzooplankton exhibit higher feeding rates during the daytime, evidence from the field is scarce and contradictory. In this study, we first characterized the nano- and microplanktonic communities of the Gullmar Fjord (Sweden) and its environmental conditions during July and August 2017. Then, we explored the grazing impact of microzooplankton on the phytoplankton community of this ecosystem and assessed their diel grazing activity using the dilution technique. Finally, we evaluated the impact of mesozooplankton at natural concentrations during the experiments. Microzooplankton removed 26% of the phytoplankton standing stock and 96% of the primary production daily, while mesozooplankton did not exert a significant impact on microplankton activity. We did not detect significant diel microzooplankton grazing rhythms during the first experimental period; however, during the second part of the study, after an upwelling event, grazing rates were significantly higher during the night. Therefore, the microzooplankton grazing rhythm in natural systems may vary according to the species composition and abundances of both microzooplankton and prey communities.
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| 6. |
- Axenrot, Thomas, et al.
(författare)
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Multifrequency discrimination of fish and mysids
- 2009
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 66:6, s. 1106-1110
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Tidskriftsartikel (refereegranskat)abstract
- The opossumshrimp (Mysis relicta) is common in many lakes in the northernparts of Eurasia and North America. The shrimp is often an importantlink in the foodweb for fish, either throughout life or in earlylife stages. Generally, quantitative measurements of mysidsin large volumes of water are difficult to obtain with traditionalsampling methods. In this pilot study, measurements of volume-backscatteringstrength (Sv) at 38, 120, and 200 kHz were used to separatebackscattering from fish and mysids. Mysids were sampled withtrawls. Where mysids were caught, the correlations between mysidbiomass (dry weight) and mean Sv at 120 and 200 kHz were positive(r2 = 0.89 and 0.81, respectively). Where mysids were abundant,the Sv exhibited a characteristic frequency response. This wasnot found where mysids were scarce or absent. Therefore, areaswith great abundances of mysids can be identified, and theirbiomasses estimated from data collected during ecosystem monitoring.
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| 7. |
- Bartolino, Valerio
(författare)
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'Adaptation science' is needed to inform the sustainable management of the world's oceans in the face of climate change
- 2022
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 79, s. 457-462
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Tidskriftsartikel (refereegranskat)abstract
- The global response to the challenge of increasingly rapid and severe climate change is shifting from a focus on mitigation and remediation of impacts to a pragmatic adaptation framework. Innovative adaptive solutions that transform the way in which we manage the world's oceans and, particularly, the harvesting of marine resources in a sustainable manner, are urgently needed. In that context, ICES Journal of Marine Science solicited contributions to the themed article set (TS), "Exploring adaptation capacity of the world's oceans and marine resources to climate change". We summarize the contributions included in this TS that provide examples of emerging climate change impacts, assess system risks at subnational and international scales, prove and evaluate different adaptation options and approaches, and explore societal and stakeholder perceptions. We also provide some "food for thought" on possible future developments in a transdisciplinary "adaptation science" working at the interface between ecology, socio-economics, and policy-governance, and that will have to provide concrete solutions to the challenges represented by climate-change and anthropogenic activity. Success will depend on the extent to which new knowledge and approaches can be integrated into the decision-making process to support evidence-based climate policy and ecosystem-based management. This includes testing their effectiveness in real systems, but also consider how social acceptance of adaptive measures will/will not support their full implementation.
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| 8. |
- Bartolino, Valerio
(författare)
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Debating the effectiveness of marine protected areas
- 2018
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 75, s. 1156-1159
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Annan publikation (refereegranskat)abstract
- Increasing the size and number of marine protected areas (MPAs) is widely seen as a way to meet ambitious biodiversity and sustainable development goals. Yet, debate still exists on the effectiveness of MPAs in achieving ecological and societal objectives. Although the literature provides significant evidence of the ecological effects of MPAs within their boundaries, much remains to be learned about the ecological and social effects of MPAs on regional and seascape scales. Key to improving the effectiveness of MPAs, and ensuring that they achieve desired outcomes, will be better monitoring that includes ecological and social data collected inside and outside of MPAs. This can lead to more conclusive evidence about what is working, what is not, and why. Eight authors were asked to write about their experiences with MPA effectiveness. The authors were instructed to clearly define "effectiveness" and discuss the degree to which they felt MPAs had achieved or failed to be effective. Essays were exchanged among authors and each was invited to write a shorter "counterpoint." The exercise shows that, while experiences are diverse, many authors found common ground regarding the role of MPAs in achieving conservation targets. This exchange of perspectives is intended to promote reflection, analysis, and dialogue as a means for improving MPA design, assessment, and integration with other conservation tools.
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| 9. |
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| 10. |
- Bartolino, Valerio, et al.
(författare)
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Sidney Holt, a giant in the history of fisheries science who focused on the future: his legacy and challenges for present-day marine scientists
- 2021
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 78, s. 2182-2192
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Tidskriftsartikel (refereegranskat)abstract
- Sidney J. Holt (1926-2019) was more than a founding father of quantitative fisheries science, and the man who "helped save the great whales." His accomplishments, over a career spanning seven decades, run deeper: he was a champion of reductionism (i.e. able to identify the factors essential for management) and a systemic thinker who inspired scientists to think critically about marine conservation and management. This article draws on first-hand experiences with Sidney over the last 15years, when he regularly collaborated with scholars of the ICES Working Group on the History of Fish and Fisheries and the Oceans Past Initiative. Four main themes emerged from our reflections on Sidney's life and legacy, which constitute ongoing scientific challenges: (1) the suitability of maximum sustainable yield as a target reference point for fisheries management; (2) the future of marine mammal conservation; (3) successful implementation of ecosystem-based marine management; and (4) the value of historical perspectives for conservation and management. We consider Sidney's work across these themes, in which he readily collaborated, focused on evidence-based solutions, and, where evidence was lacking, he advocated for the "precautionary principle." We posit there is much that we, and future generations of scientists, can learn from his example.
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