Juvenile fish habitat across the inner Danish waters: Habitat association models and habitat growth models for European plaice, flounder and common sole informed by a targeted survey

The management of coastal fisheries and coastal marine areas both require information on the use and importance of coastal marine habitats for marine species. This information is certainly pertinent for exploited species dependent on these coastal habitats for specific life-history stages. This study uses two different measures of habitat suitability to build Habitat Association Models (HAMs) and Habitat Growth Models (HGMs) for juveniles of three commercially and recreationally important fish species (Pleuronectes platessa, Platichthys flesus, and Solea solea) of the Inner Danish Waters (IDW). A large scale, one-off juvenile survey was used to collect juvenile fish and directly observed environmental data. The survey informed Generalised Linear (Mixed) Models (GLMs and GLMMs), which were fit and run through repeated random sub-sampling cross-validation before being utilised to build interpolative maps of both prediction and model uncertainty. The limitations of this approach are discussed in reference to the future works required to complement and improve such static habitat suitability maps. These results can be used to inform marine spatial planning and future work into the role of juvenile habitats in supporting fishery species.