Towards high resolution modelling of potential sandeel habitat in regional seas of the north-east Atlantic

As a vital component in marine food webs, sandeels Ammodytes spp. are an important food source for a range of vulnerable birds, mammals and commercial fish species. Sandeels have a very specific sediment composition preference: >15% particles 0.25-2 mm diameter (medium and coarse sand), as demonstrated from research in the North Sea. Policy makers now recognise the necessity to protect not only seabird breeding sites but also their food species and foraging grounds. Using seabed sediment samples and underwater video from the Northern Ireland inshore zone, this study characterised habitat suitable for sandeel in the area. This was compiled with various environmental variables to inform 3 random forest habitat prediction models. Model evaluation and independent data demonstrated that the resultant habitat suitability models showed significant discrimination ability and can identify areas suitable for sandeel habitation. Equipped with this knowledge, policy makers can now target protection of such habitat to enhance conservation of internationally protected seabirds and cetaceans that rely on sandeels for continued breeding success. Further use and development of these techniques is vital in providing policy makers with the tools to formulate management strategies which properly consider and protect forage species, which in turn can provide better breeding success and persistence of threatened and endangered species.