High Resolution Spatial Mapping of Human Footprint across Antarctica and Its Implications for the Strategic Conservation of Avifauna

Assessment of marine litter on the Fields Peninsula, King George Island, Antarctica

The study presents the results of the survey of beached litter on the two opposite shores of the Fields Peninsula (King George Island) conducted during the austral summer seasons of 2022 and 2023, as part of the 67th and 68th Russian Antarctic expeditions. Beaches situated on the coast of the Drake Passage were much more polluted compared to the beaches on the Maxwell Bay side. Plastic accounted for 86 % of all found items on the shores of the Drake Passage, with the majority of items related to fisheries or shipping. On the Maxwell Bay beaches, only 36 % of litter was plastic, with other categories like wood and metal dominating the total number. The average density of marine litter is 0.32 items/m (0.017 items/m2), comparable to other similar surveys conducted on Antarctic islands; however, this is at least 15-20 times lower than beach litter densities in the Arctic.

Human infrastructures correspond to higher Adélie penguin breeding success and growth rate

Anthropogenic activities generate increasing disturbance in wildlife especially in extreme environments where species have to cope with rapid environmental changes. In Antarctica, while studies on human disturbance have mostly focused on stress response through physiological and behavioral changes, local variability in population dynamics has been addressed more scarcely. In addition, the mechanisms by which breeding communities are affected around research stations remain unclear. Our study aims at pointing out the fine-scale impact of human infrastructures on the spatial variability in Adélie penguin (Pygoscelis adeliae) colonies dynamics. Taking 24 years of population monitoring, we modeled colony breeding success and growth rate in response to both anthropic and land-based environmental variables. Building density around colonies was the second most important variable explaining spatial variability in breeding success after distance from skua nests, the main predators of penguins on land. Building density was positively associated with penguins breeding success. We discuss how buildings may protect penguins from avian predation and environmental conditions. The drivers of colony growth rate included topographical variables and the distance to human infrastructures. A strong correlation between 1-year lagged growth rate and colony breeding success was coherent with the use of public information by penguins to select their initial breeding site. Overall, our study brings new insights about the relative contribution and ecological implications of human presence on the local population dynamics of a sentinel species in Antarctica.

Patient safety culture and satisfaction in Ghana: a facility-based cross-sectional study

BACKGROUND

Globally, one of the measures of high performing healthcare facilities is the compliance of patient safety culture, which encompasses the ability of health institutions to avoid or drastically reduce patient harm or risks. These risks or harm is linked with numerous adverse patient outcomes such as medication error, infections, unsafe surgery and diagnosis error.

OBJECTIVES

The general objective of this study was to investigate into the impact of patient safety culture practices experienced on patient satisfaction among patients who attend the Kwesimintsim Government Hospital in the Takoradi municipality.

METHODS

This study was a descriptive cross-sectional study and a consecutive sampling technique was used to select 336 respondents for the study. Data was collected using a structured questionnaire and processed using Statistical Package for Social Sciences, V.21. Both descriptive and inferential statistics were carried out and result were presented using figures and tables.

RESULTS

The study found that the overall patient safety compliance level observed by the respondents was poor (29.2%). The prevalence of adverse events experienced among the respondents was high (58%). The leading adverse events mentioned were medication errors, followed by wrong prescriptions and infections. The consequences of these adverse events encountered by the respondents were mentioned as increased healthcare costs (52%), followed by hospitalisation (43%), worsening of health conditions (41%) and contraction of chronic health conditions (22%). Patient safety cultural practices such as teamwork (β=0.17, p=0.03), response to error (β=0.16, p=0.005), communication openness (β=0.17, p=0.003) and handoffs and information exchange (β=0.17, p=0.002) were found to positively influence patient satisfaction.

CONCLUSION

The poor general compliance of the patient safety culture in the facility is unfortunate, and this can affect healthcare outcomes significantly. The study therefore entreats facility managers and various stakeholders to see patient safety care as an imperative approach to delivering quality essential healthcare and to act accordingly to create an environment that supports it.

Biogeographic survey of soil bacterial communities across Antarctica

BACKGROUND

Antarctica and its unique biodiversity are increasingly at risk from the effects of global climate change and other human influences. A significant recent element underpinning strategies for Antarctic conservation has been the development of a system of Antarctic Conservation Biogeographic Regions (ACBRs). The datasets supporting this classification are, however, dominated by eukaryotic taxa, with contributions from the bacterial domain restricted to Actinomycetota and Cyanobacteriota. Nevertheless, the ice-free areas of the Antarctic continent and the sub-Antarctic islands are dominated in terms of diversity by bacteria. Our study aims to generate a comprehensive phylogenetic dataset of Antarctic bacteria with wide geographical coverage on the continent and sub-Antarctic islands, to investigate whether bacterial diversity and distribution is reflected in the current ACBRs.

RESULTS

Soil bacterial diversity and community composition did not fully conform with the ACBR classification. Although 19% of the variability was explained by this classification, the largest differences in bacterial community composition were between the broader continental and maritime Antarctic regions, where a degree of structural overlapping within continental and maritime bacterial communities was apparent, not fully reflecting the division into separate ACBRs. Strong divergence in soil bacterial community composition was also apparent between the Antarctic/sub-Antarctic islands and the Antarctic mainland. Bacterial communities were partially shaped by bioclimatic conditions, with 28% of dominant genera showing habitat preferences connected to at least one of the bioclimatic variables included in our analyses. These genera were also reported as indicator taxa for the ACBRs.

CONCLUSIONS

Overall, our data indicate that the current ACBR subdivision of the Antarctic continent does not fully reflect bacterial distribution and diversity in Antarctica. We observed considerable overlap in the structure of soil bacterial communities within the maritime Antarctic region and within the continental Antarctic region. Our results also suggest that bacterial communities might be impacted by regional climatic and other environmental changes. The dataset developed in this study provides a comprehensive baseline that will provide a valuable tool for biodiversity conservation efforts on the continent. Further studies are clearly required, and we emphasize the need for more extensive campaigns to systematically sample and characterize Antarctic and sub-Antarctic soil microbial communities. Video Abstract.

Breaking the Ice: A Review of Phages in Polar Ecosystems

Bacteriophages, or phages, are viruses that infect and replicate within bacterial hosts, playing a significant role in regulating microbial populations and ecosystem dynamics. However, phages from extreme environments such as polar regions remain relatively understudied due to challenges such as restricted ecosystem access and low biomass. Understanding the diversity, structure, and functions of polar phages is crucial for advancing our knowledge of the microbial ecology and biogeochemistry of these environments. In this review, we will explore the current state of knowledge on phages from the Arctic and Antarctic, focusing on insights gained from -omic studies, phage isolation, and virus-like particle abundance data. Metagenomic studies of polar environments have revealed a high diversity of phages with unique genetic characteristics, providing insights into their evolutionary and ecological roles. Phage isolation studies have identified novel phage-host interactions and contributed to the discovery of new phage species. Virus-like particle abundance and lysis rate data, on the other hand, have highlighted the importance of phages in regulating bacterial populations and nutrient cycling in polar environments. Overall, this review aims to provide a comprehensive overview of the current state of knowledge about polar phages, and by synthesizing these different sources of information, we can better understand the diversity, dynamics, and functions of polar phages in the context of ongoing climate change, which will help to predict how polar ecosystems and residing phages may respond to future environmental perturbations.

Gender-based roles, psychosocial variation, and power relations during delivery and postnatal care: a qualitative case study in rural Ethiopia

Introduction

The World Health Organization (WHO) strongly encouraged men to support women in receiving maternal healthcare. However, especially in developing countries, maternal healthcare has traditionally been viewed as an issue in women, with men making little or no contribution, even though sexuality and children are shared products. The study aims to understand how gender-based roles, psychosocial variation, and power relations are related to child delivery and postnatal care (PNC) services.

Methods

The study was conducted in three rural districts of Oromia regional state, Jimma Zone, Ethiopia. An in-depth interview and focus group discussion were held with carefully chosen health professionals, health extension workers, community health development armies, and religious leaders. The data was collected, translated, and transcribed by experienced men and women qualitative researchers. For data analysis, ATLAS.ti version 9 was used. The data were coded and categorized concerning delivery and PNC service utilization. Independent and shared gender-based roles were identified as a means to improve maternal healthcare service delivery.

Results

The result obtained three categories, namely, gender-based roles, psychosocial variation, and power relations. Men can persuade pregnant women to use delivery services and PNC. The place of delivery is determined by the levels of gender-based power relations at the household level, but women are usually the last decision-makers. The belief of the community that giving birth in a health facility makes women look clean and neat, as opposed to home delivery, increases their intention to use maternal healthcare services.

Discussion

The study contributes that the role of a man as a husband is crucial in mobilizing others to carry pregnant women to health facilities, contributing to early intervention during labor. The decision-making capacity of women has improved over time, with men accepting their right to make decisions about their health and fetuses. Home delivery and men not being present during delivery are perceived as signs of backwardness, whereas giving birth in health institutes is seen as a sign of modernization and the rights of women.

Positive Organizational Psychology Factors as Serial Multiple Mediators of the Relationship between Organization Support and Job Satisfaction Among Peer Support Specialists

BACKGROUND

Research has demonstrated the effectiveness of peer support specialists in helping people with severe mental illness increase community tenure, decrease hospitalization, boost treatment satisfaction, improve social functioning, and increase quality of life.

OBJECTIVE

The purpose of the present study was to evaluate positive organizational psychology constructs as serial multiple mediators of the relationships between perceived organizational support and job satisfaction among peer support specialists.

METHODS

One hundred and twenty-one peer support specialists from the Texas statewide peer certification training programs and the National Association of Peer Supporters participated in the present study. These peer support specialists completed an online survey composed of self-report measures related to perceived organizational support, positive organizational psychology factors, and job satisfaction. A serial multiple mediation (SMMA) analysis was conducted to evaluate autonomous motivation to work, work engagement, and organizational commitment as mediators of the relationship between perceived organizational support and job satisfaction.

RESULTS

The SMMA model accounted for 49% of the variation in job satisfaction scores (R2 =. 49, f2 = 0.96 [> 0.35], a large effect size). Autonomous motivation to work, work engagement, and organizational commitment were significantly associated with job satisfaction after controlling for the effect of perceived organizational support.

CONCLUSIONS

Perceived organizational support increased autonomous motivation to work, work engagement, organizational commitment, and job satisfaction. Peer support specialists are integral members of the interdisciplinary mental health treatment team. Leaders of community-based mental health and rehabilitation agencies who are committed to hire and retain peer support specialists must provide strong organizational support and develop interventions to increase peer support specialists' autonomous motivation to work, work engagement, and organizational commitment as a job retention and career development strategy.

Untangling unexpected terrestrial conservation challenges arising from the historical human exploitation of marine mammals in the Atlantic sector of the Southern Ocean

Intensive human exploitation of the Antarctic fur seal (Arctocephalus gazella) in its primary population centre on sub-Antarctic South Georgia, as well as on other sub-Antarctic islands and parts of the South Shetland Islands, in the eighteenth and nineteenth centuries rapidly brought populations to the brink of extinction. The species has now recovered throughout its original distribution. Non-breeding and yearling seals, almost entirely males, from the South Georgia population now disperse in the summer months far more widely and in higher numbers than there is evidence for taking place in the pre-exploitation era. Large numbers now haul out in coastal terrestrial habitats in the South Orkney Islands and also along the north-east and west coast of the Antarctic Peninsula to at least Marguerite Bay. In these previously less- or non-visited areas, the seals cause levels of damage likely never to have been experienced previously to fragile terrestrial habitats through trampling and over-fertilisation, as well as eutrophication of sensitive freshwater ecosystems. This increased area of summer impact is likely to have further synergies with aspects of regional climate change, including reduction in extent and duration of sea ice permitting seals access farther south, and changes in krill abundance and distribution. The extent and conservation value of terrestrial habitats and biodiversity now threatened by fur seal distribution expansion, and the multiple anthropogenic factors acting in synergy both historically and to the present day, present a new and as yet unaddressed challenge to the agencies charged with ensuring the protection and conservation of Antarctica's unique ecosystems.

Environment-triggered demographic changes cascade and compound to propel a dramatic decline of an Antarctic seabird metapopulation

While seabirds are well-known for making a living under some of the harshest conditions on the planet, their capacity to buffer against unfavourable conditions can be stretched in response to ecosystem change. During population increases, overlap between conspecifics can limit population growth through competition for breeding or feeding resources. What is less well understood is the role that intrinsic processes play during periods of population decline or under a changing environment. We interrogate key demographic parameters and their biophysical drivers to understand the role of intrinsic and extrinsic drivers during a recent near halving of a large Adélie penguin (Pygoscelis adeliae) metapopulation. The loss of 154,000 breeding birds along the 100-km East Antarctic coastline centred around 63°E over the last decade diverges from a sustained increase over preceding decades and is contrary to recent models that predict a continued increase. The decline was initially triggered by changed environmental conditions: more extensive near-shore sea ice caused a reduction in breeding success. The evidence suggests this decline was exacerbated by feedback processes driving an inverse density-dependent decrease in fledgling survival in response to smaller cohort size. It appears that the old adage of safety in numbers may shape the fledgling penguins' chances of survival and, if compromised over multiple years, could exacerbate difficulties during population decline or if feedback processes arise. The likely interplay between demographic parameters meant that conditions were more unfavourable and negative effects more rapid than would be expected if demographic processes acted in isolation or independently. Failure to capture both intrinsic and extrinsic drivers in predictive population models may mean that the real impacts of climate change on species' populations are more severe than projections would lead us to believe. These results improve our understanding of population regulation during periods of rapid decline for long-lived marine species.

Rhamnolipid-Coated Iron Oxide Nanoparticles as a Novel Multitarget Candidate against Major Foodborne E. coli Serotypes and Methicillin-Resistant S. aureus

Surface-growing antibiotic-resistant pathogenic bacteria such as Escherichia coli and Staphylococcus aureus are emerging as a global health challenge due to dilemmas in clinical treatment. Furthermore, their pathogenesis, including increasingly serious antimicrobial resistance and biofilm formation, makes them challenging to treat by conventional therapy. Therefore, the development of novel antivirulence strategies will undoubtedly provide a path forward in combatting these resistant bacterial infections. In this regard, we developed novel biosurfactant-coated nanoparticles to combine the antiadhesive/antibiofilm properties of rhamnolipid (RHL)-coated Fe3O4 nanoparticles (NPs) with each of the p-coumaric acid (p-CoA) and gallic acid (GA) antimicrobial drugs by using the most available polymer common coatings (PVA) to expand the range of effective antibacterial drugs, as well as a mechanism for their synergistic effect via a simple method of preparation. Mechanistically, the average size of bare Fe3O4 NPs was ~15 nm, while RHL-coated Fe3O4@PVA@p-CoA/GA was about ~254 nm, with a drop in zeta potential from -18.7 mV to -34.3 mV, which helped increase stability. Our data show that RHL-Fe3O4@PVA@p-CoA/GA biosurfactant NPs can remarkably interfere with bacterial growth and significantly inhibited biofilm formation to more than 50% via downregulating IcaABCD and CsgBAC operons, which are responsible for slime layer formation and curli fimbriae production in S. aureus and E. coli, respectively. The novelty regarding the activity of RHL-Fe3O4@PVA@p-CoA/GA biosurfactant NPs reveals their potential effect as an alternative multitarget antivirulence candidate to minimize infection severity by inhibiting biofilm development. Therefore, they could be used in antibacterial coatings and wound dressings in the future. IMPORTANCE Antimicrobial resistance poses a great threat and challenge to humanity. Therefore, the search for alternative ways to target and eliminate microbes from plant, animal, and marine microorganisms is one of the world's concerns today. Furthermore, the extraordinary capacity of S. aureus and E. coli to resist standard antibacterial drugs is the dilemma of all currently used remedies. Methicillin-resistant S. aureus (MRSA) and vancomycin-resistant S. aureus (VRSA) have become widespread, leading to no remedies being able to treat these threatening pathogens. The most widely recognized serotypes that cause severe foodborne illness are E. coli O157:H7, O26:H11, and O78:H10, and they display increasing antimicrobial resistance rates. Therefore, there is an urgent need for an effective therapy that has dual action to inhibit biofilm formation and decrease bacterial growth. In this study, the synthesized RHL-Fe3O4@PVA@p-CoA/GA biosurfactant NPs have interesting properties, making them excellent candidates for targeted drug delivery by inhibiting bacterial growth and downregulating biofilm-associated IcaABCD and CsgBAC gene loci.

The beneficial effects of omega-3 polyunsaturated fatty acids on controlling blood pressure: An umbrella meta-analysis

Several meta-analyses have revealed that n-3 PUFAs can lower blood pressure, but the findings are conflicting. In this regard, the present umbrella meta-analysis aimed was performed to clarify whether n-3 PUFAs have effects on blood pressure. PubMed, Scopus, Embase, Web of Science, and Google Scholar were used as international databases from inception to May 2022. To examine the effects of n-3 PUFA supplementation on blood pressure, a random-effects model was applied. The leave-one-out method was performed for the sensitivity analysis. The pooled estimate of 10 meta-analyses with 20 effect sizes revealed significant reductions in both systolic (ES = -1.19 mmHg; 95% CI: -1.76, -0.62, p < 0.001) and diastolic blood pressure (ES = -0.91 mmHg, 95% CI: -1.35, -0.47; p < 0.001) following n-3 PUFAs supplementation. In studies with a sample size of ≤ 400 participants and a mean age over 45, SBP and DBP were found to be substantially reduced. Overall, this umbrella meta-analysis indicates that n-3 PUFAs supplementation might play a role in improving DBP and SBP.

Metals and metalloids in Antarctic krill and water in deep Weddell Sea areas

The study on the concentration of trace elements in Antarctic krill and in water in the deep areas of the Atlantic sector of the Antarctic was performed. Concentrations of 22 trace elements were studied to determine their spatial distribution in krill, and to assess the accumulation ability of the krill against 8 of them. The trace elements concentration in krill diminished in the following order: Fe > Cu > Zn > Bа > B > Se > As > Cr > Ni > Ag > Li > Mn > V > Mo > Cd > Co > Hg > Be. Concentrations of Pb, Ti, Tl, Sb were below their detection limits. Concentration factors of trace elements by krill varied from n × 10² to n × 10⁴. The Cu and As concentrations in dry krill exceeded their MPC. Concentrations of all trace elements in wet mass of krill were not exceeded established regulative values.

What are the real environmental impacts of Antarctic tourism? Unveiling their importance through a comprehensive meta-analysis

Human activities in Antarctica were increasing before the COVID-19 pandemic, and tourism was not an exception. The growth and diversification of Antarctic tourism over the last few decades have been extensively studied. However, environmental impacts associated with this activity have received less attention despite an increasing body of scholarship examining environmental issues related to Antarctic tourism. Aside from raising important research questions, the potential negative effects of tourist visits in Antarctica are also an issue discussed by Antarctic Treaty Consultative Parties. This study presents the results of a meta-analysis of scholarly publications that synthesizes and updates our current knowledge of environmental impacts resulting from Antarctic tourism. A first publication database containing 233 records that focussed on this topic was compiled and subjected to a general bibliometric and content analysis. Further, an in-depth content analysis was performed on a subset of 75 records, which were focussed on showing specific research on Antarctic tourism impacts. The main topic, methods, management proposals, and research gaps highlighted by the respective authors of these 75 publications were assessed. The range of research topics addressed, the methods used - including the application of established research designs from the field of environmental impact assessment -, and the conclusions reached by the study authors are discussed. Interestingly, almost one third of the studies did not detect a direct relationship between tourism and significant negative effects on the environment. Cumulative impacts of tourism have received little attention, and long-term and comprehensive monitoring programs have been discussed only rarely, leading us to assume that such long-term programs are scarce. More importantly, connections between research and policy or management do not always exist. This analysis highlights the need for a comprehensive strategy to investigate and monitor the environmental impacts of tourism in Antarctica. A first specific research and monitoring programme to stimulate a debate among members of the Antarctic scientific and policy communities is proposed, with the ultimate goal of advancing the regulation and management of Antarctic tourism collaboratively.

Recent Reports on Redox Stress-Induced Mitochondrial DNA Variations, Neuroglial Interactions, and NMDA Receptor System in Pathophysiology of Schizophrenia

Schizophrenia (SZ) is a chronic psychiatric disorder affecting several people worldwide. Mitochondrial DNA (mtDNA) variations could invoke changes in the OXPHOS system, calcium buffering, and ROS production, which have significant implications for glial cell survival during SZ. Oxidative stress has been implicated in glial cells-mediated pathogenesis of SZ; the brain comparatively more prone to oxidative damage through NMDAR. A confluence of scientific evidence points to mtDNA alterations, Nrf2 signaling, dynamic alterations in dorsolateral prefrontal cortex (DLPFC), and provocation of oxidative stress that enhance pathophysiology of SZ. Furthermore, the alterations in excitatory signaling related to NMDAR signaling were particularly reported for SZ pathophysiology. Current review reported the recent evidence for the role of mtDNA variations and oxidative stress in relation to pathophysiology of SZ, NMDAR hypofunction, and glutathione deficiency. NMDAR system is influenced by redox dysregulation in oxidative stress, inflammation, and antioxidant mediators. Several studies have demonstrated the relationship of these variables on severity of pathophysiology in SZ. An extensive literature search was conducted using Medline, PubMed, PsycINFO, CINAHL PLUS, BIOSIS Preview, Google scholar, and Cochrane databases. We summarize consistent evidence pointing out a plausible model that may elucidate the crosstalk between mtDNA alterations in glial cells and redox dysregulation during oxidative stress and the perturbation of NMDA neurotransmitter system during current therapeutic modalities for the SZ treatment. This review can be beneficial for the development of promising novel diagnostics, and therapeutic modalities by ascertaining the mtDNA variations, redox state, and efficacy of pharmacological agents to mitigate redox dysregulation and augment NMDAR function to treat cognitive and behavioral symptoms in SZ.

Research sites get closer to field camps over time: Informing environmental management through a geospatial analysis of science in the McMurdo Dry Valleys, Antarctica

As in many parts of the world, the management of environmental science research in Antarctica relies on cost-benefit analysis of negative environmental impact versus positive scientific gain. Several studies have examined the environmental impact of Antarctic field camps, but very little work looks at how the placement of these camps influences scientific research. In this study, we integrate bibliometrics, geospatial analysis, and historical research to understand the relationship between field camp placement and scientific production in the McMurdo Dry Valleys of East Antarctica. Our analysis of the scientific corpus from 1907-2016 shows that, on average, research sites have become less dispersed and closer to field camps over time. Scientific output does not necessarily correspond to the number of field camps, and constructing a field camp does not always lead to a subsequent increase in research in the local area. Our results underscore the need to consider the complex historical and spatial relationships between field camps and research sites in environmental management decision-making in Antarctica and other protected areas.

Prognostic and Clinicopathologic Significance of Discoidin Domain Receptors in Different Human Malignancies: A Meta-Analysis

Background

Discoidin domain receptors (DDRs) belong to the receptor tyrosine kinases family and are activated by different types of collagens, which play roles in various physiological processes. An abnormal expression of DDRs is reported in different types of cancers. Despite many reports about the association and roles of high DDR expression levels in cancers, the prognostic values of DDRs are still unclear. This meta-analysis was performed to evaluate the prognostic effect of DDRs in different tissue cancers.

Method

A literature search was performed in several related databases to find eligible English articles. Based on our research, 20 appropriate studies with 2,602 patients were selected till October 5, 2020. The pooled hazard ratio (HR) with a corresponding 95% confidence interval (CI) was computed to evaluate the strength of correlation between DDRs and survival of cancer patients.

Result

Pooling results showed that a high DDR expression was significantly associated with poorer overall survival (OS) (HR = 1.304, 95% CI 1.007-1.69, p = 0.04). Subgroup analysis based on cancer type revealed a significant link between a high DDR expression level and poor OS both in gastrointestinal (pooled HR = 1.78, 95% CI 1.214-2.624, p = 0.003) and urological cancers (pooled HR = 1.42, 95% CI 1.062-1.82, p = 0.018).

Conclusion

Our meta-analysis results suggest that high DDRs expression has the potential to be used as a biomarker of poor prognosis in cancers.

Mercury Levels in Feathers of Penguins from the Antarctic Peninsula Area: Geographical and Inter-Specific Differences

Polar regions, symbols of wilderness, have been identified as potential sinks of mercury coming from natural and anthropogenic sources at lower latitudes. Changes in ice coverage currently occurring in some areas such as the Antarctic Peninsula could enhance these phenomena and their impacts on local biota. As long-lived species at the top of food chains, seabirds are particularly sensitive to this highly toxic metal with the capacity to be biomagnified. Specifically, their feathers can be useful for Hg monitoring since they mainly accumulate its most toxic and persistent form, methyl-Hg. To that end, feathers of gentoo (Pygoscelis papua), chinstrap (P. antarcticus), and Adélie penguins (P. adeliae) (n = 108) were collected by passive sampling in seven different locations throughout the Antarctic Peninsula area and analyzed by ICP-MS after microwave-digestion. More than 93% of the samples showed detectable Hg levels (range: 6.3–12,529.8 ng g⁻¹ dry weight), and the highest ones were found in the feathers of chinstrap penguins from King George Island. Hg bioconcentration and biomagnification seem to be occurring in the Antarctic food web, giving rise to high but non-toxic Hg levels in penguins, similar to those previously found in Arctic seabirds.

Pitfalls and advances in morphometric sexing: insights from the Adélie penguin Pygoscelis adeliae

Sexing weakly/criptically dimorphic birds requires invasive techniques or molecular analysis. Alternatively, sexing can be based upon morphometric analysis, which remains invaluable in remote field conditions such as Polar regions. Nevertheless, discriminatory power may be affected by methodological issues hampering comparison between/within studies, e.g. considering alternative analytical techniques or measurements taken by different researchers. We investigated the sexing potential of bill length, bill depth and body mass in adult Adélie penguins Pygoscelis adeliae of known sex. We performed discriminant analysis on a large dataset of measurements (237 males; 264 females) taken from penguins marked between 1994 and 2001, at Edmonson Point (Ross Sea, Antarctica). In a second step, we accounted for measurements collected by different researchers through permuted discriminant analysis. We found moderate support for sex discrimination through bill measurements (77%). Considering body mass did not improve classification power substantially (78.2%), possibly because of confounding inter/intra-annual oscillations in body condition. Discriminant rate decreased when controlling the researcher effect (72.7% and 71.4%, respectively). Results were also confirmed by logistic (mixed) models. Simulations showed that reduction in sample size markedly increased uncertainty in classification power. Differences with previous studies achieving a slightly greater classification power for sexing Adélie penguins through morphometrics could be related to (i) our higher sample size and/or (ii) geographical, population-specific differences, e.g. lower degree of sexual dimorphism. Our work emphasises key-factors influencing performance of morphometric sexing in avian species, advocating population-specific validation with large sample size as well as the necessity to account for the researcher effect prior to apply morphometric sexing.

Adaptive Management of Sustainable Tourism in Antarctica: A Rhetoric or Working Progress?

Growth and diversification of tourism activities in Antarctica have not been matched by proactive strategies for planning or management. Recognizing that the adaptive management approach has been effectively implemented in managing tourism in protected areas, we examine to what extent this approach has been incorporated into the Antarctic tourism research and management, and what constraints exist for its implementation. To better understand the extent of literature contributions, we conducted an appraisal of 72 peer-reviewed journal articles published from 1992 to 2020 and Antarctic management documents. From a scientific perspective, researchers have been advocating for adaptive management approaches to Antarctic tourism and have applied different elements, particularly ecological assessments, design of management measures, monitoring, and regulatory mechanisms. However, these contributions have not been necessarily translated into management policy and regulations. We acknowledge that full implementation of an adaptive management approach is not easily achievable due to the unique Antarctic regime. However, we argue that comprehensive site-specific and regional adaptive management models could be applied as the first step for a more systematic implementation. This incremental approach could contribute to enhanced stakeholder participation and improved decision-making processes, ultimately leading to a more proactive and effective management of Antarctic tourism, essential for the conservation of the continent.

Local Drivers of Change in Southern Ocean Ecosystems: Human Activities and Policy Implications

Local drivers are human activities or processes that occur in specific locations, and cause physical or ecological change at the local or regional scale. Here, we consider marine and land-derived pollution, non-indigenous species, tourism and other human visits, exploitation of marine resources, recovery of marine mammals, and coastal change as a result of ice loss, in terms of their historic and current extent, and their interactions with the Southern Ocean environment. We summarise projected increases or decreases in the influence of local drivers, and projected changes to their geographic range, concluding that the influence of non-indigenous species, fishing, and the recovery of marine mammals are predicted to increase in the future across the Southern Ocean. Local drivers can be managed regionally, and we identify existing governance frameworks as part of the Antarctic Treaty System and other instruments which may be employed to mitigate or limit their impacts on Southern Ocean ecosystems.

Microbial Communities in Permafrost Soils of Larsemann Hills, Eastern Antarctica: Environmental Controls and Effect of Human Impact

Although ice-free areas cover only about 0.1% of Antarctica and are characterized by harsh environmental conditions, these regions provide quite diverse conditions for the soil-forming process, having various physical and geochemical properties, and also assuring different conditions for living organisms. This study is aimed to determine existing soil microbial communities, their relationship with soil parameters and the influence of anthropogenic activity in Larsemann Hills, Eastern Antarctica. The soil microbiome was investigated at different locations using 16S rRNA gene pyrosequencing. The taxonomic analysis of the soil microbiomes revealed 12 predominant bacterial and archaeal phyla—Proteobacteria, Actinobacteria, Acidobacteria, Chloroflexi, Gemmatimonadetes, Verrucomicrobia, Planctomycetes, Bacteroidetes, Armatimonadetes, Firmicutes, Cyanobacteria, Thaumarchaeota. Some specific phyla have been also found in sub-surface horizons of soils investigated, thus providing additional evidence of the crucial role of gravel pavement in saving the favorable conditions for both soil and microbiome development. Moreover, our study also revealed that some bacterial species might be introduced into Antarctic soils by human activities. We also assessed the effect of different soil parameters on microbial community in the harsh environmental conditions of Eastern Antarctica. pH, carbon and nitrogen, as well as fine earth content, were revealed as the most accurate predictors of soil bacterial community composition.

Ecological impacts of human-induced animal behaviour change

A growing body of literature has documented myriad effects of human activities on animal behaviour, yet the ultimate ecological consequences of these behavioural shifts remain largely uninvestigated. While it is understood that, in the absence of humans, variation in animal behaviour can have cascading effects on species interactions, community structure and ecosystem function, we know little about whether the type or magnitude of human-induced behavioural shifts translate into detectable ecological change. Here we synthesise empirical literature and theory to create a novel framework for examining the range of behaviourally mediated pathways through which human activities may affect different ecosystem functions. We highlight the few empirical studies that show the potential realisation of some of these pathways, but also identify numerous factors that can dampen or prevent ultimate ecosystem consequences. Without a deeper understanding of these pathways, we risk wasting valuable resources on mitigating behavioural effects with little ecological relevance, or conversely mismanaging situations in which behavioural effects do drive ecosystem change. The framework presented here can be used to anticipate the nature and likelihood of ecological outcomes and prioritise management among widespread human-induced behavioural shifts, while also suggesting key priorities for future research linking humans, animal behaviour and ecology.

Assessing distribution shifts and ecophysiological characteristics of the only Antarctic winged midge under climate change scenarios

Parts of Antarctica were amongst the most rapidly changing regions of the planet during the second half of the Twentieth Century. Even so, today, most of Antarctica remains in the grip of continental ice sheets, with only about 0.2% of its overall area being ice-free. The continent's terrestrial fauna consists only of invertebrates, with just two native species of insects, the chironomid midges Parochlus steinenii and Belgica antarctica. We integrate ecophysiological information with the development of new high-resolution climatic layers for Antarctica, to better understand how the distribution of P. steinenii may respond to change over the next century under different IPCC climate change scenarios. We conclude that the species has the potential to expand its distribution to include parts of the west and east coasts of the Antarctic Peninsula and even coastal ice-free areas in parts of continental Antarctica. We propose P. steinenii as an effective native sentinel and indicator species of climate change in the Antarctic.

Invasive non-native species likely to threaten biodiversity and ecosystems in the Antarctic Peninsula region

The Antarctic is considered to be a pristine environment relative to other regions of the Earth, but it is increasingly vulnerable to invasions by marine, freshwater and terrestrial non-native species. The Antarctic Peninsula region (APR), which encompasses the Antarctic Peninsula, South Shetland Islands and South Orkney Islands, is by far the most invaded part of the Antarctica continent. The risk of introduction of invasive non-native species to the APR is likely to increase with predicted increases in the intensity, diversity and distribution of human activities. Parties that are signatories to the Antarctic Treaty have called for regional assessments of non-native species risk. In response, taxonomic and Antarctic experts undertook a horizon scanning exercise using expert opinion and consensus approaches to identify the species that are likely to present the highest risk to biodiversity and ecosystems within the APR over the next 10 years. One hundred and three species, currently absent in the APR, were identified as relevant for review, with 13 species identified as presenting a high risk of invading the APR. Marine invertebrates dominated the list of highest risk species, with flowering plants and terrestrial invertebrates also represented; however, vertebrate species were thought unlikely to establish in the APR within the 10 year timeframe. We recommend (a) the further development and application of biosecurity measures by all stakeholders active in the APR, including surveillance for species such as those identified during this horizon scanning exercise, and (b) use of this methodology across the other regions of Antarctica. Without the application of appropriate biosecurity measures, rates of introductions and invasions within the APR are likely to increase, resulting in negative consequences for the biodiversity of the whole continent, as introduced species establish and spread further due to climate change and increasing human activity.

Antarctic environmental change and biological responses

Antarctica and the surrounding Southern Ocean are facing complex environmental change. Their native biota has adapted to the region's extreme conditions over many millions of years. This unique biota is now challenged by environmental change and the direct impacts of human activity. The terrestrial biota is characterized by considerable physiological and ecological flexibility and is expected to show increases in productivity, population sizes and ranges of individual species, and community complexity. However, the establishment of non-native organisms in both terrestrial and marine ecosystems may present an even greater threat than climate change itself. In the marine environment, much more limited response flexibility means that even small levels of warming are threatening. Changing sea ice has large impacts on ecosystem processes, while ocean acidification and coastal freshening are expected to have major impacts.

Human-mediated dispersal of terrestrial species between Antarctic biogeographic regions: A preliminary risk assessment

The distribution of terrestrial biodiversity within Antarctica is complex, with 16 distinct biogeographic regions (Antarctic Conservation Biogeographic Regions) currently recognised within the Antarctic continent, Peninsula and Scotia Arc archipelagos of the Antarctic Treaty area. Much of this diversity is endemic not only to Antarctica as a whole, but to specific regions within it. Further complexity is added by inclusion of the biodiversity found on the islands located in the Southern Ocean north of the Treaty area. Within Antarctica, scientific, logistic and tourism activities may inadvertently move organisms over potentially long distances, far beyond natural dispersal ranges. Such translocation can disrupt natural species distribution patterns and biogeography through: (1) movement of spatially restricted indigenous species to other areas of Antarctica; (2) movement of distinct populations of more generally distributed species from one area of Antarctica to another, leading to genetic homogenisation and loss of assumed local patterns of adaptation; and (3) further dispersal of introduced non-native species from one area of Antarctica to another. Species can be moved between regions in association with people and cargo, by ship, aircraft and overland travel. Movement of cargo and personnel by ship between stations located in different biogeographic regions is likely to present one of the greatest risks, particularly as coastal stations may experience similar climatic conditions, making establishment more likely. Recognising that reducing the risk of inter-regional transfer of species is a priority issue for the Antarctic Treaty Consultative Meeting, we make practical recommendations aimed at reducing this risk, including the implementation of appropriate biosecurity procedures.

Soil features in rookeries of Antarctic penguins reveal sea to land biotransport of chemical pollutants

The main soil physical-chemical features, the concentrations of a set of pollutants, and the soil microbiota linked to penguin rookeries have been studied in 10 selected sites located at the South Shetland Islands and the Antarctic Peninsula (Maritime Antarctica). This study aims to test the hypothesis that biotransport by penguins increases the concentration of pollutants, especially heavy metals, in Antarctic soils, and alters its microbiota. Our results show that penguins do transport certain chemical elements and thus cause accumulation in land areas through their excreta. Overall, a higher penguin activity is associated with higher organic carbon content and with higher concentrations of certain pollutants in soils, especially cadmium, cooper and arsenic, as well as zinc and selenium. In contrast, in soils that are less affected by penguins’ faecal depositions, the concentrations of elements of geochemical origin, such as iron and cobalt, increase their relative weighted contribution, whereas the above-mentioned pollutants maintain very low levels. The concentrations of pollutants are far higher in those penguin rookeries that are more exposed to ship traffic. In addition, the soil microbiota of penguin-influenced soils was studied by molecular methods. Heavily penguin-affected soils have a massive presence of enteric bacteria, whose relative dominance can be taken as an indicator of penguin influence. Faecal bacteria are present in addition to typical soil taxa, the former becoming dominant in the microbiota of penguin-affected soils, whereas typical soil bacteria, such as Actinomycetales, co-dominate the microbiota of less affected soils. Results indicate that the continuous supply by penguin faeces, and not the selectivity by increased pollutant concentrations is the main factor shaping the soil bacterial community. Overall, massive penguin influence results in increased concentrations of certain pollutants and in a strong change in taxa dominance in the soil bacterial community.