Periodic Reporting for period 3 - MEESO (Ecologically and economically sustainable mesopelagic fisheries)
Période du rapport: 2022-09-01 au 2024-02-29
MEESO’s overall goal is to quantify the spatio-temporal distributions of biomass, production and ecosystem role of mesopelagic resources and to assess sustainable management options for their exploitation. To achieve this, MEESO has established new knowledge and data on the mesopelagic community, its biodiversity, drivers of its biomass, its role in carbon sequestration, and its interactions with the overlying epipelagic communities which include important commercial fish stocks. MEESO has developed and implemented new acoustic and trawling technologies needed for obtaining data from this remote and poorly understood marine ecosystem zone. MEESO also evaluated the potential for mesopelagic biomass to be used in the production of sustainable products for the human food chain. Combining, for the first time, leading experts in science, engineering, fisheries, and governance, MEESO has developed commercial fishing and processing technologies and mapping of contaminant and nutrient contents to explore the basis for a viable fishery and job creation. With the new tools and technologies at hand, as well as assessment and management roadmaps, MEESO has assessed the trade-offs between exploitation, sustainability, and viability of the resource, and identified options for its governance.
In MEESO we have developed and tested new submersible platforms with acoustic and optical technologies and new fine-meshed trawl designs. A review of their use, including a summary of standard sampling techniques, has been written as a protocol for future mesopelagic surveys. During MEESO cruises we have used new technologies to provide new estimates of mesopelagic diversity, biomass and individual size. One of the trawls is now used as standard equipment on Norwegian and Icelandic ecosystem surveys.
We have investigated three different commercial midwater trawls with different mesh sizes focusing on catch efficiency and homogeneity of the catch. Furthermore, we investigated which processing methods would be suitable for mesopelagic species. The most commonplace processes all proved applicable and are hypothesised to be the most likely with commercial viability. Biotechnological development of the mesopelagic catch was also performed with experimental identification of different compounds with potential use in biotechnological applications such as nutraceutical or pharmacological.
Field campaigns were conducted in the North Atlantic, covering large areas with both acoustic surveys and net sampling down to 1000 m depth. Regional maps of acoustic abundance were created and estimates of biomass in the mesopelagic were improved. The influence of hydrographical parameters on the vertical distribution of key fish species has been studied and new insights into trophic interactions and pathways of carbon flow revealed. Demographic parameters essential for understanding the population dynamics of key fish species in the mesopelagic layers were produced.
We have delivered new biomass and key demographic parameter estimates for B. glaciale and M. muelleri. We have identified spatial growth and mortality variations and estimated MSY and associated reference points, indicating high productivity but uncertainty regarding sustainable fishing. An ensemble of population and ecosystem models was used to explore resilience to future harvesting and climate change. Projections suggest fluctuating MSYs and climate vulnerability for M. muelleri, suggesting theoretical feasibility but practical challenges for sustainable harvesting, especially amid climate change uncertainties.
Based on technical and economic insights gained through stakeholder workshops and interviews and various databases, bioeconomic models were developed to evaluate management strategies and to perform a cost-benefit analysis including monetised climate impacts. Stakeholder workshops, a survey, a behavioural experiment, and automated contents analysis (ACA) of social media posts were carried out to analyse public understanding of mesopelagic fisheries. Observational field work on research vessels and ACA of scientific abstracts analysed the role of scientific practices in forming frames and perceptions of the mesopelagic zone.
MEESO studied the governance of mesopelagic fishery sustainability. Analyzing 2700+ policy documents, it found few policies protecting mesopelagic fish. Policies for climate, biodiversity, and fish tend to be isolated, hindering integrated ecosystem management. Interviews revealed gaps in governance but highlighted collaboration opportunities with RFMO, High Seas treaty, area-based management, impact assessment, and ecosystem-based fisheries management. Deep uncertainty analysis showed tradeoffs between fishing and preserving climate services, with potential costs outweighing benefits. Geographical analysis revealed governance challenges for species-level management, such as migratory stocks and trans-boundary effects beyond national jurisdiction.
For capacity building and promoting new techniques, methods, models and key knowledge to the public, external stakeholders and governance bodies, MEESO has published over 5 e-learning courses and webinars on key models and new methods. Additionally, 2 public videos on best surveying and fishing practices were released for general and future use, and 14 workshops for feedback were conducted. The project results have been disseminated through more than 35 papers in high ranking scientific peer reviewed journals and in 4+ popular science publications.
We have investigated three different commercial midwater trawls with different mesh sizes focusing on catch efficiency and homogeneity of the catch. Furthermore, we investigated which processing methods would be suitable for mesopelagic species. The most commonplace processes all proved applicable and are hypothesised to be the most likely with commercial viability. Biotechnological development of the mesopelagic catch was also performed with experimental identification of different compounds with potential use in biotechnological applications such as nutraceutical or pharmacological.
Field campaigns were conducted in the North Atlantic, covering large areas with both acoustic surveys and net sampling down to 1000 m depth. Regional maps of acoustic abundance were created and estimates of biomass in the mesopelagic were improved. The influence of hydrographical parameters on the vertical distribution of key fish species has been studied and new insights into trophic interactions and pathways of carbon flow revealed. Demographic parameters essential for understanding the population dynamics of key fish species in the mesopelagic layers were produced.
We have delivered new biomass and key demographic parameter estimates for B. glaciale and M. muelleri. We have identified spatial growth and mortality variations and estimated MSY and associated reference points, indicating high productivity but uncertainty regarding sustainable fishing. An ensemble of population and ecosystem models was used to explore resilience to future harvesting and climate change. Projections suggest fluctuating MSYs and climate vulnerability for M. muelleri, suggesting theoretical feasibility but practical challenges for sustainable harvesting, especially amid climate change uncertainties.
Based on technical and economic insights gained through stakeholder workshops and interviews and various databases, bioeconomic models were developed to evaluate management strategies and to perform a cost-benefit analysis including monetised climate impacts. Stakeholder workshops, a survey, a behavioural experiment, and automated contents analysis (ACA) of social media posts were carried out to analyse public understanding of mesopelagic fisheries. Observational field work on research vessels and ACA of scientific abstracts analysed the role of scientific practices in forming frames and perceptions of the mesopelagic zone.
MEESO studied the governance of mesopelagic fishery sustainability. Analyzing 2700+ policy documents, it found few policies protecting mesopelagic fish. Policies for climate, biodiversity, and fish tend to be isolated, hindering integrated ecosystem management. Interviews revealed gaps in governance but highlighted collaboration opportunities with RFMO, High Seas treaty, area-based management, impact assessment, and ecosystem-based fisheries management. Deep uncertainty analysis showed tradeoffs between fishing and preserving climate services, with potential costs outweighing benefits. Geographical analysis revealed governance challenges for species-level management, such as migratory stocks and trans-boundary effects beyond national jurisdiction.
For capacity building and promoting new techniques, methods, models and key knowledge to the public, external stakeholders and governance bodies, MEESO has published over 5 e-learning courses and webinars on key models and new methods. Additionally, 2 public videos on best surveying and fishing practices were released for general and future use, and 14 workshops for feedback were conducted. The project results have been disseminated through more than 35 papers in high ranking scientific peer reviewed journals and in 4+ popular science publications.
To achieve its main goal MEESO has used technology and methods that are state-of-the-art, and beyond, in five themes: Technology, Knowledge acquisition, Management, Governance and Capacity building. We have set new standards for measuring and quantifying mesopelagic resources by deploying submersed wideband echosounders and larger fine-meshed trawls. We have also progressed the on-board and on-land processing of mesopelagic biomass.
Our analysis of growth rates, natural mortality, asymptotic size, maturity, and length-weight relationships of Mueller´s pearlside and glacier lanternfish has revealed high natural mortality rate estimates. Our suite of novel population and ecosystem models is functional and has been used in assessments of harvest strategies and climate change scenarios. The bioeconomic models developed have enabled researchers to evaluate sustainable management strategies for the mesopelagic zone, and to quantify the various trade-offs. The cost-benefit analysis for mesopelagic fishing is the first that considers the impact of mesopelagic fisheries on the global climate through reduced vertically migrating stocks. Stakeholder consultations have yielded a comprehensive overview of public concerns that determine public legitimacy of mesopelagic fisheries. Despite the paucity of existing governance options, we identified opportunities for area-based management and environmental impact assessment, and collaboration with RFMOs to protect the mesopelagic. We also identified the potential value of carbon services of the mesopelagic under main area-based management scenarios that were identified during policy analyses. MEESO has contributed to capacity building for the public, stakeholders, and governance bodies by publishing more than 5 e-learning courses and webinars on key models and methods, 2 public videos on best surveying and fishing practices, and more than 35 papers in peer reviewed journals.
Our analysis of growth rates, natural mortality, asymptotic size, maturity, and length-weight relationships of Mueller´s pearlside and glacier lanternfish has revealed high natural mortality rate estimates. Our suite of novel population and ecosystem models is functional and has been used in assessments of harvest strategies and climate change scenarios. The bioeconomic models developed have enabled researchers to evaluate sustainable management strategies for the mesopelagic zone, and to quantify the various trade-offs. The cost-benefit analysis for mesopelagic fishing is the first that considers the impact of mesopelagic fisheries on the global climate through reduced vertically migrating stocks. Stakeholder consultations have yielded a comprehensive overview of public concerns that determine public legitimacy of mesopelagic fisheries. Despite the paucity of existing governance options, we identified opportunities for area-based management and environmental impact assessment, and collaboration with RFMOs to protect the mesopelagic. We also identified the potential value of carbon services of the mesopelagic under main area-based management scenarios that were identified during policy analyses. MEESO has contributed to capacity building for the public, stakeholders, and governance bodies by publishing more than 5 e-learning courses and webinars on key models and methods, 2 public videos on best surveying and fishing practices, and more than 35 papers in peer reviewed journals.