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The great auk was once abundant and distributed across the North Atlantic. It is now extinct, having been heavily exploited for its eggs, meat, and feathers. We investigated the impact of human hunting on its demise by integrating genetic data, GPS-based ocean current data, and analyses of population viability. We sequenced complete mitochondrial genomes of 41 individuals from across the species' geographic range and reconstructed population structure and population dynamics throughout the Holocene. Taken together, our data do not provide any evidence that great auks were at risk of extinction prior to the onset of intensive human hunting in the early 16th century. In addition, our population viability analyses reveal that even if the great auk had not been under threat by environmental change, human hunting alone could have been sufficient to cause its extinction. Our results emphasise the vulnerability of even abundant and widespread species to intense and localised exploitation.

Southwest Greenland constitutes an internationally important wintering area for seabirds, including Thick-billed Murres (Uria lomvia (Linnaeus, 1758)), but their prey may be affected by the general warming of this sub-Arctic region. We compared murre diet collected in winter in the 1990s and in the 2010s around Nuuk, Greenland. Fish made up 36% of the diet (wet mass) and crustaceans 63% in the 1990s, changing to 22% and 78% in the 2010s, respectively. Capelin (Mallotus villosus (Muller, 1776)) was the dominant fish species, and the smaller contribution in the 2010s coincided with declining densities of capelin around Nuuk. The crustaceans were dominated by two krill species (Meganyctiphanes norvegica (M. Sars, 1857) and Thysanoessa inermis (Kroyer, 1846)). However, M. norvegica was only important in the 2010s (51% wet mass), while T. inermis was dominating the 1990s with 62% wet mass and only 23% in the 2010s. The dominance of M. norvegica in the 2010s confirmed our expectations of a gradual 'borealization' of this region due to the generally warming sub-Arctic. The smaller contribution of fish in the diet may also support the hypothesis of deteriorating winter conditions for murres. Apart from the diet, plastic was found in 15% of the birds and 53% had parasitic nematodes. Key words: seabird winter diet, Thick-billed Murre, Uria lomvia, southwest Greenland, borealization, krill, capelin, Mallotus villosus. Si le sud-ouest du Groenland constitue une aire d'hivernage d'importance internationale pour les oiseaux marins, incluant le guillemot de Brunnich (Uria lomvia (Linnaeus, 1758)), le rechauffement general de cette region subarctique pourrait avoir une incidence sur leurs proies. Nous comparons les regimes alimentaires hivernaux de guillemots durant les annees 1990 et 2010 dans les environs de Nuuk (Groenland). Les poissons constituaient 36 % (masse humide) de leur alimentation et les crustaces, 63 %, dans les annees 1990, ces proportions passant a 22 % et 78 %, respectivement, durant les annees 2010. Le capelan (Mallotus villosus (Muller, 1776)) etait l'espece de poisson dominante, et le plus faible pourcentage de poissons dans les annees 2010 coincide avec des densites de capelans reduites aux environs de Nuuk. Parmi les crustaces consommes, deux especes de krill (Meganyctiphanes norvegica (M. Sars, 1857) et Thysanoessa inermis (Kroyer, 1846)) dominaient. Toutefois, M. norvegica n'etait important que dans les annees 2010 (51 % masse humide), alors que T. inermis etait dominant dans les annees 1990 (62 % masse humide, contre seulement 23 % durant les annees 2010). La predominance de M. norvegica dans les annees 2010 confirme nos predictions d'une <> progressive de cette region decoulant du rechauffement general de la region subarctique. La diminution de la proportion des poissons dans l'alimentation pourrait egalement appuyer l'hypothese de la deterioration des conditions hivernales pour les guillemots. Du plastique a egalement ete retrouve dans 15 % des oiseaux, et 53 % etaient parasites par des nematodes. [Traduit par la Redaction] Mots-cles: alimentation hivernale des oiseaux marins, guillemot de Brunnich, Uria lomvia, sud-ouest du Groenland, borealisation, krill, capelan, Mallotus villosus., Introduction For migratory bird populations, the non-breeding season represents a very long and usually challenging period of their annual cycle, and their survival and subsequent breeding performance are highly dependent [...]

Vertebrate populations are often monitored as part of broader assessments of ecosystem status, where they are expected to provide information on the ability of the ecosystem to support higher‐level predators. However, because many vertebrates are long‐lived and often only subsets of their populations can be monitored, abundance may not be sufficiently responsive to ecosystem status to provide early warnings of impending changes. Marine birds are often used as indicators of ecosystem status but, due to their long lifespan and delayed recruitment to the breeding population, changes in abundance are generally slow and often difficult to interpret. Their breeding productivity is, however, also widely monitored and much more responsive to ecosystem status, but the relevance of variation in productivity may be difficult to assess. We propose a model‐based indicator that integrates monitoring of abundance and breeding productivity through demographic matrix models. The metric of the proposed indicator is the expected population growth rate, given the observed level of breeding productivity. This expected growth rate is then compared with a threshold derived from the criteria employed for red‐listing of threatened species by the International Union for the Conservation of Nature. We demonstrate the suggested approach using data from Black‐legged Kittiwakes Rissa tridactyla in the Greater North Sea region, Northwest Europe. The proposed indicator shows that the current level of breeding productivity is expected to lead to a population decline of 3–4% per year, which is equivalent to a red‐list status as Endangered for the species in this region. Our indicator approach is used in OSPAR's Quality Status Report 2023 and is expected to be used by European Union member states for reporting under the Marine Strategy Framework Directive in 2024. Our approach represents a major step forward in assessing the status of marine bird populations; the ideal next step would be to develop a coherent Integrated Population Modelling (IPM) framework that would allow inclusion of all data on population abundance and demography collected across the large and diverse marine ecosystems involved. [ABSTRACT FROM AUTHOR]

This paper explores modes of expectation among care‐experienced young people when navigating educational success. Luhmann's theoretical framework is used to conceptualise experiences of educational success and the role of uncertainty. We identify three modes of expectation: trust, risk and danger. To illustrate these modes, we draw on selected examples from an interview study with 28 care‐experienced young people focusing on their experiences of support and aftercare while transitioning out of care. The trust mode of expectation is based in a confidence that the future entails a positive outcome—in the case of this study, regarding educational success. This expectation is characterised by the young person's feelings of belonging, underpinned by a safety net of unconditionally supportive caregivers. The risk mode of expectation is characterised by the young person's feeling of being overwhelmed and burdened by the complexity of the educational system in combination with unknown future circumstances when leaving care. The battle against child welfare services to keep supportive measures increases levels of uncertainty. The danger mode of expectation emerges when educational success is disrupted by the interference of child welfare services. The system is seen as unpredictable and powerful, making the young person withdraw from formal support. We conclude that educational success for care‐experienced young people is closely linked to their mode of expectation with regard to managing the uncertainty of the future and that their mode is highly dependent on their social, institutional and biographical contexts. [ABSTRACT FROM AUTHOR]

In the present work, we employed a customised electrolyser test cell to quantify the electrocatalytic activity of a high-performing Co–Co(OH) 2 /nickel foam electrocatalyst, towards the hydrogen evolution reaction (HER) under industrial-relevant alkaline electrolysis conditions. The Co–Co(OH) 2 electrocatalyst was synthesized by a wet chemical deposition route followed by thermal decomposition, fully covering the nickel foam support. In conventional 3-electrode tests, the synthesized Co–Co(OH) 2 electrocatalyst revealed a 78 mV overpotential at 10 mA cm−2 exhibiting a promising performance compared to the 290 mV measured for pristine nickel foam. Further testing under industrial-relevant conditions with a customised electrolyser cell configuration proves that the electrocatalysts lower the cell potential by 200 mV at 200 mA cm−2 compared to pristine nickel foam after 118 h of electrochemical measurements at 80 °C using a 30 wt% KOH electrolyte solution. These findings indicate that the high performance achieved for the Co–Co(OH) 2 electrocatalyst could potentially be translated to industrial-relevant environments. [Display omitted] • Electrolysis cell for testing at industrial conditions (30 wt% KOH, 80 °C) is employed. • Cobalt hydroxycarbonate nanowire arrays are converted to Co–Co(OH) 2 on a nickel foam (NF) support. • Co–Co(OH) 2 /NF shows low HER overpotential of 78 mV at 10 mA cm−2 at 1 M KOH, RT. • Co–Co(OH) 2 /NF electrolyser tested at industrial conditions shows increased stability compared to NF. • Co–Co(OH) 2 /NF electrolyser needs 1.9 V to deliver 200 mA cm−2 at industrial conditions. [ABSTRACT FROM AUTHOR]