NECCTON: Report on all 16 model coupling developments (D7.2)

The overall objective of NECCTON is to enable the Copernicus Marine Service to deliver products that inform marine biodiversity conservation and food resources management, by fusing ocean ecosystem models and data. Marine higher trophic level products, including those related to marine fish, have, as of now, not been available in the Copernicus portfolio. The outcomes of the higher trophic level (HTL) model developments described in this report aligns with UN Sustainable Development Goal 14 (SDG Life below water: fishes and marine mammals) and support fish-stock assessments for the Common Fisheries Policy Regulation (CFP). This report synthesizes the model developments of HTL model capabilities as described in task 7.2. This includes description of HTL models, coupling to LTL models and presenting results from model evaluation.

In NECCTON, the HTL products are prepared for different Copernicus Marine Service regions by developing a range of models of different complexity and type. The models fall into three categories, marine ecosystem biomass models (FEISTY - Petrik et al 2019, Denderen et al 2021; Ecospace - Libralato and Solidoro 2009; EcoOcean - Coll et al. 2020; MIZER - Bruggeman 2021; E2E - Daewel et al. 2019; SPF - Gkanasos et al., 2021), Species Distribution Models (SS-DBEM multi-species - Wilson et al. 2021; ESD-Med species -  von Schuckmann et al. 2021; NAWH-cetaceans -  Romagosa et al 2019), and Species Population Models (DEB-IBM small pelagics - Bueno-Pardo et al., 2020; Menu et al., 2023; Ev-OSMOSE - Morell et al. 2023; SEAPODYM – Lehodey et al 2008; Senina et al 2020). These models were selected to enable an ensemble approach for certain regions and gain insights into the suitability and readiness of various existing modelling approaches to provide operational HTL products for Copernicus Marine Service in the future.

The report shows that NECCTON has advanced the field of marine higher trophic level modelling by better integrating higher and lower trophic levels with improving fishing representations and better representation of spatial and temporal scales. Models now feature improved trophic coupling (including two-way links, consumption constrained to primary/secondary production, benthic–pelagic coupling), finer spatial resolution and movement/migration schemes, and seasonal to decadal variability. For some model spatially dynamic fishing is included, which is a prerequisite for related management scenarios. Functionally, coverage spans small pelagics, demersals, invertebrates, and marine mammals across regions, including the Mediterranean, Black Sea, Atlantic and Arctic Ocean, and Bay of Biscay, yielding outputs from biomass maps to decision-support tools. Together these advances deliver a more integrated, spatially explicit suite of models needed to deliver management relevant products for HTL in the context of Copernicus Marine Service.