Periodic Reporting for period 4 - SUMMER (Sustainable management of mesopelagic resources)
Okres sprawozdawczy: 2023-09-01 do 2024-08-31
The objective of SUMMER was to establish a protocol to accurately estimate mesopelagic fish biomass, quantify the ecosystem services provided by the mesopelagic community and develop a decision support tool to quantitatively balance the trade-offs between the different services for any given exploitation scenario.
SUMMER has provided a guide of “how to” estimate the biomass of this sea layer, using a combination of different acoustic and e-DNA methodologies. This combination has been applied to different contrasting sites obtaining that the biomass in the mesopelagic layer represents around 87% of the total epipelagic one. Of this biomass, 44% of the organisms perform a daily excursion to the epipelagic zone during the night and back to the mesopelagic during the day. These excursions provide a carbon transfer that seems to be relevant for climate regulation. With 1.3PgCY-1 transferred, this ecosystem service outweighs other ecosystem services such as the provision of fishmeal or fish oil. It was found that commercial viability is limited due to the fish's wide and thin distribution and the need for transformation into fishmeal and fish oil. Unique biochemical traits of mesopelagic microbial communities were highlighted as promising sources for new pharmaceutical products.
The research emphasized the critical ecological role of mesopelagic fish in carbon sequestration and food webs, highlighting significant risks of overfishing from the social perspective. Legal and regulatory frameworks are not yet in place, with the new Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction expected to influence and collaborate with a future regional fisheries management organization for mesopelagic species. This is, however, in the event a fishery is deemed sustainable, where the BBNJ treaty can contribute to sustainable management practices, most specifically within the context of the development of potential area-based management tools including potential marine protected areas and environmental impact assessments for other activities that may have an impact on a potential mesopelagic fishery.
SUMMER has provided a guide of “how to” estimate the biomass of this sea layer, using a combination of different acoustic and e-DNA methodologies. This combination has been applied to different contrasting sites obtaining that the biomass in the mesopelagic layer represents around 87% of the total epipelagic one. Of this biomass, 44% of the organisms perform a daily excursion to the epipelagic zone during the night and back to the mesopelagic during the day. These excursions provide a carbon transfer that seems to be relevant for climate regulation. With 1.3PgCY-1 transferred, this ecosystem service outweighs other ecosystem services such as the provision of fishmeal or fish oil. It was found that commercial viability is limited due to the fish's wide and thin distribution and the need for transformation into fishmeal and fish oil. Unique biochemical traits of mesopelagic microbial communities were highlighted as promising sources for new pharmaceutical products.
The research emphasized the critical ecological role of mesopelagic fish in carbon sequestration and food webs, highlighting significant risks of overfishing from the social perspective. Legal and regulatory frameworks are not yet in place, with the new Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction expected to influence and collaborate with a future regional fisheries management organization for mesopelagic species. This is, however, in the event a fishery is deemed sustainable, where the BBNJ treaty can contribute to sustainable management practices, most specifically within the context of the development of potential area-based management tools including potential marine protected areas and environmental impact assessments for other activities that may have an impact on a potential mesopelagic fishery.
Review and compilation of existing knowledge has been complemented with new data and analytical outputs. This includes establishing the main predator species and preys of mesopelagic species. Results show that mesopelagic fish species can feed on a high diversity of resources, and numerous trophic interspecific segregations appear to structure oceanic food webs. Species that appear to be close taxonomically or morphologically appear to have adopted different feeding strategies. It has been further obtained how all top predators depend to varying degrees on mesopelagic resources.
Reducing the uncertainty of the biomass estimations will require the combination of different methods. A “How to estimate mesopelagic biomass” guide has been produced. Using models, an estimation of the global biomass gives us a result that is 10-fold lower than previous estimations.
We have presented the first direct comparison of three key components of the Biological Carbon Pump at contrasting sites. Regarding these active fluxes it has been obtained that migratory mesopelagic fish are responsible for 9-28% of the total export of carbon to the twilight zone.
Novel insights into the identity and biogeography of potential microbial omega-3 producers has been developed based on metagenomic data mining. However, the exact products of the putative omega-3 biosynthetic gene clusters identified should be assessed further to verify their ability to produce these fatty acids. Most of the identified candidates remain uncultured, which implies that this is not a short-term route to obtain microbial PUFA suppliers. The mesopelagic layer is an interesting niche to find novel bioactive compounds. Furthermore, the gut microbiome of some mesopelagic fish species is dominated by potential omega-3 fatty acid producers, which could represent alternatives for omega-3 production relevant in the fields of nutraceuticals and aquaculture. Finally, we obtained how although technically feasible, financially processing fishmeal and oil or hydrolysates from mesopelagic fishes seems complex.
An economic analysis of whether it is worth exploiting or not the OTZ has been performed.
Through a literature review it has been screened the potential regulatory framework of fishing mesopelagics, both under the scope of RFMOs, high seas treaties, and under the EU fishing regulatory framework.
SUMMER partners have published 90 peer-reviewed articles. 103 data resources were published complying with the FAIR approach, including georeferenced data archived, genetic resources, and data and code. A school in which new scientists were trained in all aspects of the SUMMER research program, from data obtention to data treatment, including different techniques and on producing advice. In addition to the normal dissemination procedures through social media, we released the “Metropelagic” exhibition. At different metro stations in Bilbao, pictures of the mesopelagic diversity were exhibited. A symposium was organized, in where the main outputs of SUMMER were presented. A workshop with the industry was held in which interesting discussions around a potential mesopelagic fishery took place.
Reducing the uncertainty of the biomass estimations will require the combination of different methods. A “How to estimate mesopelagic biomass” guide has been produced. Using models, an estimation of the global biomass gives us a result that is 10-fold lower than previous estimations.
We have presented the first direct comparison of three key components of the Biological Carbon Pump at contrasting sites. Regarding these active fluxes it has been obtained that migratory mesopelagic fish are responsible for 9-28% of the total export of carbon to the twilight zone.
Novel insights into the identity and biogeography of potential microbial omega-3 producers has been developed based on metagenomic data mining. However, the exact products of the putative omega-3 biosynthetic gene clusters identified should be assessed further to verify their ability to produce these fatty acids. Most of the identified candidates remain uncultured, which implies that this is not a short-term route to obtain microbial PUFA suppliers. The mesopelagic layer is an interesting niche to find novel bioactive compounds. Furthermore, the gut microbiome of some mesopelagic fish species is dominated by potential omega-3 fatty acid producers, which could represent alternatives for omega-3 production relevant in the fields of nutraceuticals and aquaculture. Finally, we obtained how although technically feasible, financially processing fishmeal and oil or hydrolysates from mesopelagic fishes seems complex.
An economic analysis of whether it is worth exploiting or not the OTZ has been performed.
Through a literature review it has been screened the potential regulatory framework of fishing mesopelagics, both under the scope of RFMOs, high seas treaties, and under the EU fishing regulatory framework.
SUMMER partners have published 90 peer-reviewed articles. 103 data resources were published complying with the FAIR approach, including georeferenced data archived, genetic resources, and data and code. A school in which new scientists were trained in all aspects of the SUMMER research program, from data obtention to data treatment, including different techniques and on producing advice. In addition to the normal dissemination procedures through social media, we released the “Metropelagic” exhibition. At different metro stations in Bilbao, pictures of the mesopelagic diversity were exhibited. A symposium was organized, in where the main outputs of SUMMER were presented. A workshop with the industry was held in which interesting discussions around a potential mesopelagic fishery took place.
Attempts to model the dynamics of mesopelagic food webs and fishing effects have been hampered by lack of empirical data on the trophic links and energy flow mediated by mesopelagic organisms within the vertically integrated food web. In SUMMER a combination of historical data and analyses of stomach contents, lipid composition, stable isotopes, and morphological functional diversity of samples collected has help on assessing the trophic role of mesopelagic taxa. These complementary approaches indicate that, far from being a homogeneous whole, mesopelagic fish species can feed on a high diversity of resources and occupy a broad range of isotopic niches
It has obtained new insight in terms of biodiversity of this sea layer, carbon fluxes and therefore the role of the mesopelagic zone in the carbon sequestration, and specifically of the diel vertical migration of mesopelagic fishes. We confirmed how mesopelagics represents approximately 87% of the pelagic biomass), and that far from being a homogeneous whole, mesopelagic fish species can feed on a high diversity of resources, and numerous trophic interspecific segregations appear to structure oceanic food webs. Species that appear to be close taxonomically or morphologically adopt different feeding strategies. We also have learnt how their slow metabolism makes their productivity low and highly vulnerable to fishing.
A tradeoff analysis of the ecosystem services currently provided by the mesopelagic layer and their potential under exploitation has been performed. Methods to estimate abundance of biomasses of mesopelagic fishes have been tested and assessed. Based on that the two main objectives of SUMMER are fulfilled: How to estimate biomass has been achieved producing a guide. The answer to the question of fishing or not is more inclined towards protecting then than exploiting them, at least from the fishing perspective. It is acknowledged that results are still under big uncertainties, but SUMMER has produced the tools to reduce this uncertainty in future research avenues.
It has obtained new insight in terms of biodiversity of this sea layer, carbon fluxes and therefore the role of the mesopelagic zone in the carbon sequestration, and specifically of the diel vertical migration of mesopelagic fishes. We confirmed how mesopelagics represents approximately 87% of the pelagic biomass), and that far from being a homogeneous whole, mesopelagic fish species can feed on a high diversity of resources, and numerous trophic interspecific segregations appear to structure oceanic food webs. Species that appear to be close taxonomically or morphologically adopt different feeding strategies. We also have learnt how their slow metabolism makes their productivity low and highly vulnerable to fishing.
A tradeoff analysis of the ecosystem services currently provided by the mesopelagic layer and their potential under exploitation has been performed. Methods to estimate abundance of biomasses of mesopelagic fishes have been tested and assessed. Based on that the two main objectives of SUMMER are fulfilled: How to estimate biomass has been achieved producing a guide. The answer to the question of fishing or not is more inclined towards protecting then than exploiting them, at least from the fishing perspective. It is acknowledged that results are still under big uncertainties, but SUMMER has produced the tools to reduce this uncertainty in future research avenues.