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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.

Climate change is impacting marine ecosystems throughout the circumpolar Arctic, altering seasonal habitats and the food bases for fishes, seabirds, and marine mammals. Arctic and Subarctic regions provide resources for resident species and for species that migrate to the north from more southerly regions. Changes in northerly latitudes thus impact endemic as well as non-endemic animals. Herein, we review what is known about climate-driven changes in the migration patterns of Arctic and Subarctic marine vertebrates, including: 1) Arctic residents with seasonal movements – those fishes, seabirds, and marine mammals that complete their entire life cycle within the Arctic but exhibit seasonal movements; 2) Breeding migrants – many seabirds enter the Arctic to breed and subsequently migrate south in the fall; and 3) Summer visitors for feeding – certain species of boreal fishes, seabirds and marine mammals arrive during the northern summer to feed on abundant prey though they breed elsewhere. Migratory movements are often driven by the timing and extent of sea ice, which defines suitable habitat for some animals and limits access to open water and prey for others. Longer open-water seasons, warmer ocean temperatures, and stronger winds have resulted in earlier production blooms in spring and often, extended open-ocean plankton blooms into late summer, resulting in altered prey types and distributions. A common thread among taxa is that shifts in distribution and timing of migrating animals indicate they are traveling farther north, or shifting longitudinally, and migrations are occurring over longer seasonal time frames. Species performing multiple lifetime migrations or long-distance migrants may need to adjust migration timing or routing iteratively to match changes in marine productivity. Altered animal distributions or phenology, and reduced sea ice, affects access to animals that are critical nutritional, economical, and cultural components of Indigenous people's lives in the Arctic. Ongoing changes challenge the resilience and adaptability of Arctic people and ecosystems, and will require adaptive research and management approaches. [ABSTRACT FROM AUTHOR]

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]