The product, developed by Deltares in cooperation with the Dutch Ministry of Infrastructure and Transport, identifies areas suitable for reef habitats in the North Sea based on four key species occurrences and environmental variables such as bathymetry, grain size distribution, temperature and salinity.
The aim of this project was to predict as accurately as possible where four reef-building species in the North Sea: Sabellaria spinulosa, Modiolus modiolus, Lanice conchilega and Ostrea edulis can develop stable populations, given the environmental gradients and the gradients in human use of the North Sea. This report documents the compilation of a habitat suitability map.
For the three species that currently have stable populations in the North Sea (Sabellaria, Modiolus and Lanice), spatial distribution data were derived from EMODnet Biology. In addition, for Sabellaria and Modiolus data of macrobenthic bycatch in fishing trawls of Wageningen Marine Research were used. Lanice was too sparsely distributed in these data to be considered reliable. For Ostrea edulis, historic data on the distribution in the nineteenth and early twentieth century in Dutch, German and Belgian waters was used from literature sources. Environmental data were derived from a recent compilation in the literature, and in addition from Deltares physical modelling.
Figure 1. EMODnet Mapviewer Screenshot Sabellaria spinulosa habitat suitability in the North Sea
The presence/absence of the species was regressed on the environmental data using two regression models: logistic regression and random forest regression. The results of both models were in close agreement for all species. The random forest models gave the finest- grained predictions and are taken as the final product of the project.
The product was developed by Deltares in cooperation with the Dutch Ministry of Infrastructure and Transport and is developed further from an earlier use case.
The product is available via the EMODnet catalogue and EMODnet Map Viewer and the EMODnet GitHub hosts the repository for the code and workflow used to create this product.
