Mixed Fisheries model for the North Sea

The FLBEIA model (Garcia et al. 2017) is used by ICES to provide mixed-fisheries advice for the North Sea. The model used to provide advice was further developed during the ECOMAN project.

This web application is summarising the results by stock, by fleet and shows the analysis of potential choke species for each of the fleets - you can navigate to these results from the top of the page. The presented information is dynamic, you can chose the stocks or fleets from the menus in the left of each page. Potential implementation of recent gear developments in the Danish fleet or all fleets in the greater North Sea are explored. The medium term forecasts are presented for three different scenarios.

Included stocks

The model includes 10 fish stocks shown below. Additionally, 10 Norway lobster functional units from the greater North Sea area are included.

Stock code Species name Area
COD-NS Cod North Sea and Skagerrak
HAD Haddock North Sea, West of Scotland and Skagerrak
PLE-EC Plaice English Channel
PLE-NS Plaice North Sea
POK Saithe North Sea, Rockall and West of Scotland, Skagerrak, and Kattegat
SOL-EC Sole English Channel
SOL-NS Sole North Sea
TUR Turbot North Sea
WHG-NS Whiting North Sea
WIT Witch flounder North Sea, Skagerrak, Kattegat and English Channel


The goal of this study was to analyze if developments can reduce the choke species issues for Danish fisheries in the North Sea and Skagerrak. The European Maritime and Fisheries Fund (EMFF) and National Fisheries Agency grant number 39809 (UnCod), focuses on analyzing data from Danish gear technology developments. These results were used to estimate significant changes in TR1 and TR2 gear catchability compared to the current gears used in the Danish fishery (TR1= trawl gear >=100mm and TR2=trawl gear 70-100 mm TR1 is usually used for fish stocks and TR2 for Nephrops)

Here, we present a 10-year forecast (2021-2030) of three different effort scenarios and three gear development scenarios described below.

Scenario code Description Notes
max For each fleet, fishing stops when the TAC quota has been filled for all stocks This option causes overfishing of the single-stock advice possibilities of most stocks
min For each fleet, fishing stops when the TAC quota is filled for one of the stocks This option causes underutilization of the TAC for the other stocks, compared to the single-stock advice. This scenario can is useful to identify potential “choke species”
sq Status quo effort: the effort of each fleet during the projection period is equal to that in the most recent year for which landings and discard data are available
Baseline Current gear selectivity
DK Danish fleets changes to new gears
All All fleets change to the new gears

Fleet information

<10 Beam Beam <24 Beam >=24 Beam >=40 Beam24-40 DSeine FDF Nets Otter Otter <10 Otter <24 Otter >=24 Otter >=40 Otter10-40 Otter24-40 Pelagic Seine Static