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Classifying movement behaviour of marine predators in relation to anthropogenic activity and environmental conditions is important to guide marine conservation. We studied the relationship between grey seal (Halichoerus grypus) behaviour and environmental variability in the southwestern Baltic Sea where seal-fishery conflicts are increasing. We used multiple environmental covariates and proximity to active fishing nets within a multivariate hidden Markov model (HMM) to quantify changes in movement behaviour of grey seals while at sea. Dive depth, dive duration, surface duration, horizontal displacement, and turning angle were used to identify travelling, resting and foraging states. The likelihood of seals foraging increased in deeper, colder, more saline waters, which are sites with increased primary productivity and possibly prey densities. Proximity to active fishing net also had a pronounced effect on state occupancy. The probability of seals foraging was highest

The ICES Benchmark Workshop on Baltic Cod Stocks (WKBALTCOD), chaired by External Chair Jean-Jacques Maguire, Canada and ICES Chair Marie Storr-Paulsen, Denmark, and attended by two invited external experts Verena Trenkel, France and Meaghan Bryan, USA met in Rostock, Germany, 2–6 March 2015 with 39 participants and six countries represented. The objective of WKBALTCOD was to evaluate the appropriateness of data and methods to determine stock status and investigate meth-ods appropriate to use in the single-stock assessment for the cod stock in SD 22–24 and cod in SD 25–32 in the Baltic. Participants in the workshop were a large group with diverse backgrounds representing the industry, fisheries, NGOs, managers and scientists.The single-stock analytic assessment of the eastern Baltic stock was not accepted by the assessment working group (WGBFAS) in 2014 due to severe problems with the input data. The advice for the eastern Baltic cod was, therefore, based on the ICES approach for data-limited stocks. As an outcome ICES decided to establish a bench-mark for both cod stocks and to scope an integrated assessment for the Baltic cod stocks. The first meeting (WKSIBCA) was therefore meant to introduce the interces-sional work conducted since the assessment working group in April 2014, and to reach some conclusions on how to proceed both in the short term (Benchmark in March 2015) and longer term (2–3 years) and was seen as a data compilation work-shop, there is produced a separate report from this workshop. The WKBALTCOD was the 2nd meeting in the benchmark process and was intended to come up with a final stock assessment method, stock annex and input data for both stocks. As it was not possible to reach conclusive decision on the final model to be used for the east Baltic cod stock during the benchmark meeting and as more work on the preferable models was needed, it was decided by the ACOM leadership to prolong the bench-mark process until the assessment working group me

The Greifswalder Bodden (GWB) is considered to be the most important spawning and nursery area for the western Baltic spring-spawning herring. However, the biotic and abiotic reasons for this are still unclear. Consequently, we investigated larval growth conditions in the GWB and in the Kiel Canal (KC), another nursery and spawning area of Baltic herring. We investigated prey quantity and quality [copepod abundance and essential fatty acid (EFA) concentration] as well as biochemically derived growth rates and fatty acid content of larval herring in spring 2011. A significant correlation between larval growth and larval EFA concentration could be observed in the GWB. The highest growth rates and EFA concentrations in the larval herring coincided with high food quality. Compensating effects of food quality on food quantity and vice versa could be observed in both the GWB and the KC. While larval growth rates in the KC were high early in the season, highest growth rates in the GWB were achieved late in the season. In conclusion, neither area was superior to the other, indicating similar growth conditions for larval herring within the region.