Biologging, remotely-sensed oceanography and the continuous plankton recorder reveal the environmental determinants of a seabird wintering hotspot

Marine environments are greatly affected by climate change, and understanding how this perturbation affects marine vertebrates is a major issue. In this context, it is essential to identify the environmental drivers of animal distribution. Here, we focused on the little auk (Alle alle), one of the world’s most numerous seabirds and a major component in Arctic food webs. Using a multidisciplinary approach, we show how little auks adopt specific migratory strategies and balance environmental constraints to optimize their energy budgets. Miniature electronic loggers indicate that after breeding, birds from East Greenland migrate >2000 km to overwinter in a restricted area off Newfoundland. Synoptic data available from the Continuous Plankton Recorder (CPR) indicate that this region harbours some of the highest densities of the copepod Calanus finmarchicus found in the North Atlantic during winter. Examination of large-scale climatic and oceanographic data suggests that little auks favour patches of high copepod abundance in areas where air temperature ranges from 0°C to 5°C. These results greatly advance our understanding of animal responses to extreme environmental constraints, and highlight that information on habitat preference is key to identifying critical areas for marine conservation

A survey on energy efficiency in metal wire deposition processes

Additive manufacturing (AM), which includes different technologies, allows free-form parts to be produced flexibly by selectively depositing material layer after layer. Among the various AM processes, metal wire deposition (MWD), which uses a metal wire melted by a high-energy source as feedstock, has been found to be suitable for the manufacturing of low-complexity,medium-to-large components at relatively high deposition rates. Some industrial applications have been identified, despite the quality of the as-deposited surfaces, which usually require further finishing operations. Several researches have been focused on process optimization. However, there is still a lack of consolidated knowledge concerning the environmental impact and the energy efficiency of MWD, aspects that are critically surveyed in this paper. First, the unit process level is considered, and an analysis of the needed specific energy input, while the wire flow rate and the deposited materials are varied, is carried out. Second, a framework is proposed to assess the energy requirements under a cradle-to-gate perspective

Deleterious Effects of Litter on Marine Life

In this review we report new findings concerning interaction between marine debris and wildlife. Deleterious effects and consequences of entanglement, consumption and smothering are highlighted and discussed. The number of species known to have been affected by either entanglement or ingestion of plastic debris has doubled since 1997, from 267 to 557 species among all groups of wildlife. For marine turtles the number of affected species increased from 86 to 100 % (now 7 of 7 species), for marine mammals from 43 to 66 % (now 81 of 123 species) and for seabirds from 44 to 50 % of species (now 203 of 406 species). Strong increases in records were also listed for fish and invertebrates, groups that were previously not considered in detail. In future records of interactions between marine debris and wildlife we recommend to focus on standardized data on frequency of occurrence and quantities of debris ingested. In combination with dedicated impact studies in the wild or experiments, this will allow more detailed assessments of the deleterious effects of marine debris on individuals and populations