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The European eel hatches in the Sargasso Sea and migrates across the Atlantic Ocean toward Europe. At the continental shelf, larvae metamorphose into glass eels and then recruit to coastal habitats and estuaries. Among other cues, glass eels orient in situ using lunar cues, but what role this lunar compass plays in their recruitment to the coast is unknown. To assess this, we incorporated empirical in situ observations of glass eel swimming and lunar‐driven orientation into a biophysical advection model. We simulated dispersal of glass eels drifting with the North Atlantic Current to test the hypothesis that lunar‐driven swimming and orientation behavior affects recruitment to North Sea coasts. Particles were released from the continental slope north of Scotland, an obligate passage for migrating eel larvae. Four numerical experiments were conducted: one with passive drift and three including glass eel swimming speeds (ranging from 3 to 12 cm/s) and lunar‐driven orientation. With a speed of 3 cm/s, the lunar compass increased recruitment to the North Sea coasts of Southwestern Norway and Scotland by 34%–40%. Conversely, orientation behavior decreased recruitment to northern areas like Iceland (−46%), the Faroe Islands (−39%) and Northern Norway (−49%). Behavior affected the timing of recruitment to Southwestern Norway, causing peaks of abundance in May–June, but not to other regions. These results show that lunar‐driven orientation and swimming behavior observed in glass eels substantially increases their recruitment to North Sea coasts. Results agree with the distribution of eel in northern Europe, which decreases in abundance with increasing latitude. [ABSTRACT FROM AUTHOR]

The common minke whale (Balaenoptera acutorostrata) is the most abundant mammalian top predator in Icelandic continental shelf waters. Here, an account is given on the first systematic research programme into the feeding ecology of common minke whales in Icelandic waters based on an analysis of minke whale stomach contents data collected in Icelandic waters during 2003–2007. The results show pronounced spatial and temporal variation in the diet. The temporal changes include a decrease in the proportion of sandeel in the diet over the study period and a corresponding increase in herring (Clupea haerengus) and haddock (Melanogrammus aeglefinus), particularly in the southern area. The diet also differed markedly from the previously available, limited data from Icelandic waters with less krill and the cold water species capelin (Mallotus villosus) and more gadoids and herring in the more recent period. These changes in diet composition are consistent with recent changes in the Icelandic continental shelf ecosystem, including increased sea surface and bottom temperatures and changes in distribution and abundance of several fish species, including sandeel (Ammodytidae) and capelin. Although natural fluctuations cannot be ruled out at this stage, these dietary changes, together with decreased abundance in coastal waters, may reflect the responses of minke whales to a changed environment possibly driven by global warming. [ABSTRACT FROM AUTHOR]