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Species Distribution Models are commonly used with surface dynamic environmental variables as proxies for prey distribution to characterise marine top predator habitats. For oceanic species that spend lot of time at depth, surface variables might not be relevant to predict deep-dwelling prey distributions. We hypothesised that descriptors of deep-water layers would better predict the deep-diving cetacean distributions than surface variables. We combined static variables and dynamic variables integrated over different depth classes of the water column into Generalised Additive Models to predict the distribution of sperm whales Physeter macrocephalus and beaked whales Ziphiidae in the Bay of Biscay, eastern North Atlantic. We identified which variables best predicted their distribution. Although the highest densities of both taxa were predicted near the continental slope and canyons, the most important variables for beaked whales appeared to be static variables and surface to subsurface dynamic variables, while for sperm whales only surface and deep-water variables were selected. This could suggest differences in foraging strategies and in the prey targeted between the two taxa. Increasing the use of variables describing the deep-water layers would provide a better understanding of the oceanic species distribution and better assist in the planning of human activities in these habitats.

Hosted by the Flanders Marine Institute, the Joint ICES/OSPAR/HELCOM Working Group on Seabirds met in Ostende, Belgium, 1–5 October 2018. The meeting was co-chaired by Morten Frederiksen, Ian Mitchell and Volker Dierschke, and was attended by 15 members representing 11 countries. Following the tradition of the preceding meetings, the objectives of the meeting were to develop and implement indicators for seabirds under the Marine Strategy Framework Directive (MSFD), as well as to review and discuss seabird-related issues relevant for human uses of the sea. The meeting con-sisted of a series of interconnected workshops, where subgroups with floating mem-bership discussed Terms of Reference. Report chapters were drafted by Term of Reference leads and collated by the chairs. Further refinements of the existing indictor for breeding productivity in OSPAR were discussed. The suggested approach uses matrix population models to assess the impact of the observed level of breeding productivity on population growth rate, and relates the projected growth rate to IUCN criteria for species red-listing. Links between trends in population abundance (HELCOM) and potential drivers were explored. Preliminary results are complex and require further interpretation. A combined mid-winter aerial survey of the offshore Baltic was carried out in early 2016. The data have been collated, but results are not ready yet. The group discussed integration rules for GES assessments of birds under MSFD, both within and across species. ICES workshops in 2018 resulted in advice on these rules. JWGBIRD mostly agree with this advice, but propose a few changes. JWGBIRD reviewed the UK national assessment of seabirds under MSFD, and made suggestions for further development of indicators. A reporting template for the periodic assessments of OSPAR Threatened and/or De-clining Species and Habitats was tested for the black-legged kittiwake. The gro