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1.
Proc Biol Sci ; 291(2026): 20232915, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38981519

RESUMO

Archaeological studies of pre-historic Arctic cultures are often limited to artefacts and architecture; such records may be incomplete and often do not provide a continuous record of past occupation. Here, we used lake sediment archives to supplement archaeological evidence to explore the history of Thule and Dorset populations on Somerset Island, Nunavut (Canada). We examined biomarkers in dated sediment cores from two ponds adjacent to abandoned Thule settlements (PaJs-3 and PaJs-13) and compared these to sediment cores from two ponds without past human occupation. Coprostanol and epicoprostanol, δ15N measurements, sedimentary chlorophyll a and the ratio of diatom valves to chrysophyte cysts were elevated in the dated sediment profiles at both sites during Thule and Dorset occupations. Periods of pronounced human impact during the Thule occupation of the site were corroborated by 14C-dated caribou bones found at both sites that identified intense caribou hunting between ca 1185 and 1510 CE. Notably, these sediment core data show evidence of the Dorset occupation from ca 200 to 500 CE at sites where archaeological evidence was heretofore lacking. We highlight the utility of lake sediments in assisting archaeological studies to better establish the timings, peak occupations and even lifestyle practices of the Dorset and Thule Arctic peoples.


Assuntos
Arqueologia , Biomarcadores , Osso e Ossos , Sedimentos Geológicos , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Regiões Árticas , Osso e Ossos/química , Animais , Humanos , Biomarcadores/análise , Nunavut , Rena , Lagos/química
2.
Glob Chang Biol ; 30(2): e17193, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38380447

RESUMO

The Arctic is the fastest warming biome on the planet, and environmental changes are having striking effects on freshwater ecosystems that may impact the regional carbon cycle. The metabolic state of Arctic lakes is often considered net heterotrophic, due to an assumed supply of allochthonous organic matter that supports ecosystem respiration and carbon mineralization in excess of rates of primary production. However, lake metabolic patterns vary according to regional climatic characteristics, hydrological connectivity, organic matter sources and intrinsic lake properties, and the metabolism of most Arctic lakes is unknown. We sampled 35 waterbodies along a connectivity gradient from headwater to downstream lakes, on southern Victoria Island, Nunavut, in an area characterized by low precipitation, organic-poor soils, and high evaporation rates. We evaluated whether lakes were net autotrophic or heterotrophic during the open water period using an oxygen isotopic mass balance approach. Most of the waterbodies were autotrophic and sites of net organic matter production or close to metabolic equilibrium. Autotrophy was associated with higher benthic primary production, as compared to its pelagic counterpart, due to the high irradiance reaching the bottom and efficient internal carbon and nutrient cycling. Highly connected midstream and downstream lakes showed efficient organic matter cycling, as evidenced by the strong coupling between gross primary production (GPP) and ecosystem respiration, while decoupling was observed in some headwater lakes with significantly higher GPP. The shallow nature of lakes in the flat, arid region of southern Victoria Island supports net autotrophy in most lakes during the open water season. Ongoing climate changes that lengthen the ice-free irradiance period and increase rates of nutrient evapoconcentration may further promote net autotrophy, with uncertain long-term effects for lake functioning.


Assuntos
Ecossistema , Lagos , Nunavut , Canadá , Processos Autotróficos , Ciclo do Carbono , Carbono/metabolismo , Água
3.
Med Vet Entomol ; 37(4): 656-664, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37220211

RESUMO

The North has experienced unprecedented rates of warming over the past few decades, impacting the survival and development of insects and the pathogens that they carry. Since 2019, Arctic foxes from Canada (Nunavut) have been observed with fur loss inconsistent with natural shedding of fur. Adult lice were collected from Arctic foxes from Nunavut (n = 1) and Svalbard (n = 2; Norway) and were identified as sucking lice (suborder Anoplura). Using conventional PCR targeting the mitochondrial cytochrome c oxidase subunit 1 gene (cox1), lice from Canada and Svalbard were 100% similar (8 pooled samples from Nunavut and 3 pooled samples from Svalbard), indicating that there is potential gene flow between ectoparasites on Scandinavian and North American Arctic fox populations. The cox1 sequences of Arctic fox lice and dog sucking lice (Linognathus setosus) had significant differences (87% identity), suggesting that foxes may harbour a cryptic species that has not previously been recognised. Conventional PCR targeting the gltA gene for Bartonella bacteria amplified DNA from an unknown gammaproteobacteria from two pooled louse samples collected from Svalbard foxes. The amplified sequences were 100% identical to each other but were only 78% like Proteus mirabilis reported in GenBank (CP053614), suggesting that lice on Arctic foxes may carry unique microorganisms that have yet to be described.


Assuntos
Anoplura , Parasitos , Animais , Cães , Svalbard , Raposas/parasitologia , Nunavut , Noruega , Canadá , Regiões Árticas
4.
Scand J Public Health ; 51(7): 1023-1026, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36803095

RESUMO

In Canada, there are vast differences between the state of accommodation/housing, health, social inequalities, education and economic conditions for people in the northern and southern regions of the country. Overcrowding in Inuit Nunangat is a direct result of the promises made by past government policy that led to Inuit people settling in sedentary communities in the North on the understanding that they would be provided with social welfare. However, these welfare programmes proved to be either insufficient or non-existent for Inuit people. Therefore, Inuit are living in overcrowded homes in Canada, resulting in a severe housing shortage, poor-quality housing and homelessness. This has led to the spread of contagious diseases, mould, mental-health issues, gaps in education for children, sexual and physical violence, food insecurity and adverse challenges for the youth of Inuit Nunangat. This paper proposes several actions to ease the crisis. First, funding should be stable and predictable. Next, there should be ample construction of transitional homes which could be used to accommodate people before moving them into proper public housing. Policies regarding staff housing should be amended, and if possible, these vacant staff houses could provide shelter to eligible Inuit people, which could help lessen the housing crisis. The advent of COVID-19 has made the issue of affordable and safe housing more serious because without safe housing, the health, education and well-being of the Inuit people in Inuit Nunangat are in peril. This study focuses on how the governments of Canada and Nunavut are dealing with this issue.


Assuntos
Habitação , Criança , Adolescente , Humanos , Nunavut/epidemiologia , Canadá/epidemiologia , Fatores Socioeconômicos , Escolaridade
5.
Scand J Public Health ; 51(7): 1027-1032, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37042670

RESUMO

BACKGROUND: In Nunavut, where 70% of children are food insecure, many households rely on school breakfast or community food programmes for nourishment. The COVID-19 pandemic and resulting policies to reduce the spread of the disease have the potential to exacerbate existing issues, including increasing food insecurity in households. Funding programmes were implemented to limit the impact of public-health measures on household and community food security. The overall effects of the actions are not yet understood. METHODS: This project used a qualitative approach to examine the determinants of food security and sovereignty and the impact of the COVID-19 pandemic policy responses on these determinants in Arviat and Iqaluit. Narrative analysis applied within a relational epistemology was used to describe the experiences of community members in Iqaluit and Arviat during the COVID-19 pandemic. RESULTS: Seven participants were interviewed in Iqaluit (n=3) and Arviat (n=4). Key themes included the importance of decolonisation for food sovereignty, the importance of food sharing to communities and the resilience of communities during COVID-19. Community members wished to see greater support and strengthening of the country (locally harvested) food economy to increase knowledge of food and harvesting skill, and for communities to find ways to reach residents who may fall through the cracks during times of need or crisis. CONCLUSIONS: This study is one of the first to document Nunavummiut experiences and perspectives of food security and sovereignty in Arviat and Iqaluit during the COVID-19 pandemic.


Assuntos
COVID-19 , Pandemias , Criança , Humanos , Nunavut , Abastecimento de Alimentos , Inuíte , COVID-19/epidemiologia , Segurança Alimentar
6.
Oecologia ; 198(2): 393-406, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35066670

RESUMO

Seabirds breeding in the high Arctic contend with variable annual sea ice conditions, with important consequences depending on a species' unique reproductive and foraging ecology. We assessed the influence of sea ice extent and phenology on seabird breeding biology using monitoring data collected for northern fulmar (Fulmarus glacialis), glaucous gull (Larus hyperboreus), black-legged kittiwake (Rissa tridactyla), and thick-billed murre (Uria lomvia) breeding at Prince Leopold Island, Nunavut, Canada over 4 decades. We expected that years of later sea ice break-up and greater ice cover around the colony would create greater challenges to foraging and could result in delayed nest initiation, decreased colony attendance, and lower nesting success, but with distinct responses from each species. We also tested for time-lagged effects of ice conditions, where sea ice in a given year could impact food availability or juvenile recruitment in later years. Ice conditions around the colony exhibited no significant overall temporal trends or changepoints over the past 50 years (1970-2021), while counts of kittiwakes and murres increased over the study period 1975-2013. No trends were evident in counts of fulmars or gulls or in egg-laying dates or nest success for any species. However, three species (all but glaucous gulls) exhibited unique responses between breeding metrics and sea ice, highlighting how breeding decisions and outcomes may differ among species under the same environmental conditions in a given year. Time-lagged effects were only detected for kittiwake nest counts, where the date of spring ice break-up around the colony was negatively associated with counts at a 5-year lag. Greater distances to open water were associated with lower colony attendance by fulmars and later nest initiation by kittiwakes and murres. Our analyses provide additional insights to effects of sea ice on high-Arctic seabird breeding ecology, which will be useful in predicting and planning for the complex effects of a changing climate and changing human pressures on this high-latitude ecosystem and for the management of high-Arctic marine-protected areas.


Assuntos
Charadriiformes , Poluentes Ambientais , Animais , Regiões Árticas , Aves/fisiologia , Canadá , Ecossistema , Monitoramento Ambiental , Poluentes Ambientais/análise , Humanos , Camada de Gelo , Nunavut
7.
BMC Pregnancy Childbirth ; 22(1): 870, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36434515

RESUMO

BACKGROUND: The Qanuinngitsiarutiksait study aimed to develop detailed profiles of Inuit health service utilization in Manitoba, by Inuit living in Manitoba (approximately 1,500) and by Inuit from the Kivalliq region of Nunavut who travel to Manitoba to access care not available in Nunavut (approximately 16,000 per year). METHODS: We used health administrative data routinely collected in Manitoba for all services provided and developed an algorithm to identify Inuit in the dataset. This paper focused on health services used by Inuit from the Kivalliq for prenatal care and birthing. RESULTS: Our study found that approximately 80 percent of births to women from the Kivalliq region occur in Manitoba, primarily in Winnipeg. When perinatal care and birthing are combined, they constitute one third of all consults happening by Kivalliq residents in Manitoba. For scale, hospitalizations for childbirths to Kivalliq women about to only 5 percent of all childbirth-related hospitalizations in Manitoba. CONCLUSIONS: The practice of evacuating women from the Kivalliq for perinatal care and birthing is rooted in colonialism, rationalized as ensuring that women whose pregnancy is at high risk have access to specialized care not available in Nunavut. While defendable, this practice is costly, and does not provide Inuit women a choice as to where to birth. Attempts at relocating birthing to the north have proven complex to operationalize. Given this, there is an urgent need to develop Inuit-centric and culturally appropriate perinatal and birthing care in Manitoba.


Assuntos
Inuíte , Parto , Gravidez , Feminino , Humanos , Manitoba/epidemiologia , Nunavut/epidemiologia , Parto Obstétrico
8.
BMC Public Health ; 22(1): 1042, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614429

RESUMO

BACKGROUND: Nunavut, the northernmost Arctic territory of Canada, experienced three community outbreaks of the coronavirus disease 2019 (COVID-19) from early November 2020 to mid-June 2021. We sought to investigate how non-pharmaceutical interventions (NPIs) and vaccination affected the course of these outbreaks. METHODS: We used an agent-based model of disease transmission to simulate COVID-19 outbreaks in Nunavut. The model encapsulated demographics and household structure of the population, the effect of NPIs, and daily number of vaccine doses administered. We fitted the model to inferred, back-calculated infections from incidence data reported from October 2020 to June 2021. We then compared the fit of the scenario based on case count data with several counterfactual scenarios without the effect of NPIs, without vaccination, and with a hypothetical accelerated vaccination program whereby 98% of the vaccine supply was administered to eligible individuals. RESULTS: We found that, without a territory-wide lockdown during the first COVID-19 outbreak in November 2020, the peak of infections would have been 4.7 times higher with a total of 5,404 (95% CrI: 5,015-5,798) infections before the start of vaccination on January 6, 2021. Without effective NPIs, we estimated a total of 4,290 (95% CrI: 3,880-4,708) infections during the second outbreak under the pace of vaccination administered in Nunavut. In a hypothetical accelerated vaccine rollout, the total infections during the second Nunavut outbreak would have been 58% lower, to 1,812 (95% CrI: 1,593-2,039) infections. Vaccination was estimated to have the largest impact during the outbreak in April 2021, averting 15,196 (95% CrI: 14,798-15,591) infections if the disease had spread through Nunavut communities. Accelerated vaccination would have further reduced the total infections to 243 (95% CrI: 222-265) even in the absence of NPIs. CONCLUSIONS: NPIs have been essential in mitigating pandemic outbreaks in this large, geographically distanced and remote territory. While vaccination has the greatest impact to prevent infection and severe outcomes, public health implementation of NPIs play an essential role in the short term before attaining high levels of immunity in the population.


Assuntos
COVID-19 , Vacinas , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Canadá , Controle de Doenças Transmissíveis , Surtos de Doenças/prevenção & controle , Humanos , Nunavut/epidemiologia , SARS-CoV-2 , Vacinação
9.
Clin Infect Dis ; 72(12): 2187-2195, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293676

RESUMO

BACKGROUND: In the last decade, tuberculosis (TB) incidence among Inuit in the Canadian Arctic has been rising. Our aim was to better understand the transmission dynamics of TB in this remote region of Canada using whole-genome sequencing. METHODS: Isolates from patients who had culture-positive pulmonary TB in Iqaluit, Nunavut, between 2009 and 2015 underwent whole-genome sequencing (WGS). The number of transmission events between cases within clusters was calculated using a threshold of a ≤3 single nucleotide polymorphism (SNP) difference between isolates and then combined with detailed epidemiological data using a reproducible novel algorithm. Social network analysis of epidemiological data was used to support the WGS data analysis. RESULTS: During the study period, 140 Mycobacterium tuberculosis isolates from 135 cases were sequenced. Four clusters were identified, all from Euro-American lineage. One cluster represented 62% of all cases that were sequenced over the entire study period. In this cluster, 2 large chains of transmission were associated with 3 superspreading events in a homeless shelter. One of the superspreading events was linked to a nonsanctioned gambling house that resulted in further transmission. Shelter to nonshelter transmission was also confirmed. An algorithm developed for the determination of transmission events demonstrated very good reproducibility (κ score .98, 95% confidence interval, .97-1.0). CONCLUSIONS: Our study suggests that socioeconomic factors, namely residing in a homeless shelter and spending time in a gambling house, combined with the superspreading event effect may have been significant factors explaining the rise in cases in this predominantly Inuit Arctic community.


Assuntos
Mycobacterium tuberculosis , Canadá/epidemiologia , Genoma Bacteriano , Humanos , Inuíte , Epidemiologia Molecular , Mycobacterium tuberculosis/genética , Nunavut/epidemiologia , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes
10.
Emerg Infect Dis ; 27(6): 1718-1722, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34013864

RESUMO

We assessed antimicrobial resistance (AMR) in Neisseria gonorrhoeae in Nunavut, Canada, using remnant gonorrhea nucleic acid amplification test-positive urine specimens. This study confirms the feasibility of conducting N. gonorrhoeae AMR surveillance and highlights the diversity of gonococcal sequence types and geographic variation of AMR patterns in the territory.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Antibacterianos/farmacologia , Canadá , Farmacorresistência Bacteriana , Gonorreia/tratamento farmacológico , Humanos , Inuíte , Testes de Sensibilidade Microbiana , Nunavut
11.
Appl Environ Microbiol ; 87(7)2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33452030

RESUMO

Wastewater management in the Canadian Arctic is challenging due to climate extremes, small population sizes, and lack of conventional infrastructure for wastewater treatment. Although many northern communities use waste stabilization ponds (WSPs) as their primary form of wastewater treatment, few studies have explored WSP microbial communities and assessed effluent impacts on receiving waters from a microbiological perspective. Here, we used 16S rRNA gene and metagenome sequencing to characterize WSP and receiving water microbial communities for two time points bracketing the spring WSP thaw in Baker Lake (Nunavut) and compared these results to other Nunavut WSPs in Cambridge Bay and Kugluktuk. Most amplicon sequence variants (ASVs) recovered from these WSP samples belonged to the phylum Proteobacteria, with considerable variation between the three locations and only six ASVs shared among the WSPs at >0.2% relative abundance. Wastewater indicator ASVs for the Baker Lake WSP were identified, and few indicator ASVs were detected in samples originating from other upstream or downstream sites. The metagenomic data revealed a strong enrichment of antibiotic resistance genes for WSP samples relative to downstream and reference samples, especially for genes associated with macrolide resistance. Together, our results provide a baseline characterization for WSP microbial communities, demonstrate how indicator ASVs can be used to monitor attenuation and dilution of effluent microorganisms, and reveal that WSPs can serve as hot spots for antibiotic resistance genes.IMPORTANCE Given that the microbial communities of Arctic waste stabilization ponds (WSPs) are poorly studied to date, our characterization of multiple WSP systems and time points provides important baseline data that will assist with ongoing monitoring of effluent impacts on downstream aquatic ecosystems in the Arctic. This research also identifies indicator amplicon sequence variants (ASVs) of WSPs that will be helpful for future monitoring for WSP effluent attenuation and demonstrates that WSP microbial communities are enriched in antibiotic resistance genes. Given operational and infrastructure changes anticipated for wastewater treatment systems in the Arctic, baseline data such as these are essential for further development of safe and effective wastewater treatment systems.


Assuntos
Bactérias/genética , Farmacorresistência Bacteriana/genética , Metagenoma , Eliminação de Resíduos Líquidos , Águas Residuárias/microbiologia , Bactérias/efeitos dos fármacos , Microbiota , Nunavut , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Análise de Sequência de RNA
12.
BMC Public Health ; 21(1): 280, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536003

RESUMO

BACKGROUND: Tuberculosis (TB) is an important public health problem in Inuit communities across Canada, with an annual incidence rate in 2017 that was nearly 300 times higher than in Canadian-born non-Indigenous individuals. Social and behavioral factors that are prevalent in the North, such as commercial tobacco use, excessive alcohol use, food insecurity and overcrowded housing put individuals at higher risk for TB morbidity and mortality. We examined the potential impact of mitigation strategies for these risk factors, in reducing TB burden in this setting. METHODS: We created a transmission model to simulate the epidemiology of TB in Nunavut, Canada. We then used a decision analysis model to assess the potential impact of several evidence-based strategies targeting tobacco use, excessive alcohol use, food insecurity and overcrowded housing. We predicted TB incidence, TB-related deaths, quality adjusted life years (QALYs), and associated costs and cost-effectiveness over 20 years. All costs were expressed in 2018 Canadian dollars. RESULTS: Compared to a status quo scenario with no new interventions for these risk factors, the reduction strategy for tobacco use was most effective and cost-effective, reducing TB incidence by 5.5% (95% uncertainty range: 2.7-11%) over 20 years, with an estimated cost of $95,835 per TB case prevented and $49,671 per QALY gained. The addition of the food insecurity reduction strategy reduced incidence by a further 2% (0.5-3%) compared to the tobacco cessation strategy alone, but at significant cost. CONCLUSIONS: Strategies that aim to reduce commercial tobacco use and improve food security will likely lead to modest reductions in TB morbidity and mortality. Although important for the communities, strategies that address excess alcohol use and overcrowding will likely have a more limited impact on TB-related outcomes at current scale, and are associated with much higher cost. Their benefits will be more substantial with scale up, which will also likely have important downstream impacts such as improved mental health, educational attainment and food security.


Assuntos
Tuberculose , Canadá/epidemiologia , Análise Custo-Benefício , Humanos , Inuíte , Nunavut/epidemiologia , Comportamento de Redução do Risco , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
13.
Qual Health Res ; 31(14): 2602-2616, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34605697

RESUMO

In this article, we present a case study of sewing as a strategy for arts-based inquiry in health research, situated within a broader project that highlighted Nunavut Inuit women's childbirth experiences. Five focus groups were hosted as sewing sessions with pregnant women (N = 19) in Iqaluit, Nunavut (2017-2018). Women's reflections on the sessions, and the significance of sewing to Inuit, were integrated with researchers' critical reflections to examine the value of sewing as a strategy for arts-based inquiry within a focus group method: results related to the flexibility of the sessions; how collective sewing created space for voicing, sharing, and relating; sewing as a tactile and place-specific practice tied to Inuit knowledge and tradition; and lessons learned. Our results underscore the possibilities of arts-based approaches, such as sewing, to enhance data gathering within a focus group method and to contribute to more locally appropriate, place-based methods for Indigenous health research.


Assuntos
Inuíte , Pesquisa , Feminino , Grupos Focais , Humanos , Nunavut , Gravidez
14.
Mol Ecol ; 29(20): 3830-3840, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32810895

RESUMO

Polymorphisms within the prion protein gene (Prnp) are an intrinsic factor that can modulate chronic wasting disease (CWD) pathogenesis in cervids. Although wild European reindeer (Rangifer tarandus tarandus) were infected with CWD, as yet there have been no reports of the disease in North American caribou (R. tarandus spp.). Previous Prnp genotyping studies on approximately 200 caribou revealed single nucleotide polymorphisms (SNPs) at codons 2 (V/M), 129 (G/S), 138 (S/N), 146 (N/n) and 169 (V/M). The impact of these polymorphisms on CWD transmission is mostly unknown, except for codon 138. Reindeer carrying at least one allele encoding for asparagine (138NN or 138SN) are less susceptible to clinical CWD upon infection by natural routes, with the majority of prions limited to extraneural tissues. We sequenced the Prnp coding region of two caribou subspecies (n = 986) from British Columbia, Saskatchewan, Yukon, Nunavut and the Northwest Territories, to identify SNPs and their frequencies. Genotype frequencies at codon 138 differed significantly between barren-ground (R. t. groenlandicus) and woodland (R. t. caribou) caribou when we excluded the Chinchaga herd (p < .05). We also found new variants at codons 153 (Y/F) and 242 (P/L). Our findings show that the 138N allele is rare among caribou in areas with higher risk of contact with CWD-infected species. As both subspecies are classified as Threatened and play significant roles in North American Indigenous culture, history, food security and the economy, determining frequencies of Prnp genotypes associated with susceptibility to CWD is important for future wildlife management measures.


Assuntos
Cervos , Príons , Rena , Doença de Emaciação Crônica , Animais , Colúmbia Britânica , Cervos/genética , Genótipo , Territórios do Noroeste , Nunavut , Proteínas Priônicas/genética , Príons/genética , Rena/genética , Saskatchewan , Doença de Emaciação Crônica/genética
15.
Glob Chang Biol ; 26(2): 840-850, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31465583

RESUMO

Climate-driven sea ice loss has led to changes in the timing of key biological events in the Arctic, however, the consequences and rate of these changes remain largely unknown. Polar bears (Ursus maritimus) undergo seasonal changes in energy stores in relation to foraging opportunities and habitat conditions. Declining sea ice has been linked to reduced body condition in some subpopulations, however, the specific timing and duration of the feeding period when bears acquire most of their energy stores and its relationship to the timing of ice break-up is poorly understood. We used community-based sampling to investigate seasonality in body condition (energy stores) of polar bears in Nunavut, Canada, and examined the influence of sea ice variables. We used adipose tissue lipid content as an index of body condition for 1,206 polar bears harvested from 2010-2017 across five subpopulations with varying seasonal ice conditions: Baffin Bay (October-August), Davis Strait and Foxe Basin (year-round), Gulf of Boothia and Lancaster Sound (August-May). Similar seasonal patterns were found in body condition across subpopulations with bears at their nadir of condition in the spring, followed by fat accumulation past break-up date and subsequent peak body condition in autumn, indicating that bears are actively foraging in late spring and early summer. Late season feeding implies that even minor advances in the timing of break-up may have detrimental effects on foraging opportunities, body condition, and subsequent reproduction and survival. The magnitude of seasonal changes in body condition varied across the study area, presumably driven by local environmental conditions. Our results demonstrate how community-based monitoring of polar bears can reveal population-level responses to climate warming in advance of detectable demographic change. Our data on the seasonal timing of polar bear foraging and energy storage should inform predictive models of the effects of climate-mediated sea ice loss.


Assuntos
Mudança Climática , Ursidae , Animais , Regiões Árticas , Canadá , Camada de Gelo , Nunavut , Estações do Ano
16.
Environ Sci Technol ; 54(4): 2192-2201, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31961665

RESUMO

Access to clean and safe drinking water is a perpetual concern in Arctic communities because of challenging climatic conditions, limited options for the transportation of equipment and process chemicals, and the ongoing effects of colonialism. Water samples were gathered from multiple locations in a decentralized trucked drinking water system in Nunavut, Canada, over the course of one year. The results indicate that point of use drinking water quality was impacted by conditions in the source water and in individual buildings and strongly suggest that lead and copper measured at the tap were related to corrosion of onsite premise plumbing components. Humic-like substances were the dominant organic fraction in all samples, as determined by regional integration of fluorescence data. Iron and manganese levels in the source water and throughout the water system were higher in the winter and lower in the summer months. Elevated concentrations of copper (>2000 µg L-1) and lead (>5 µg L-1) were detected in tap water from some buildings. Field flow fractionation coupled with inductively coupled plasma mass spectrometry and ultraviolet-visible spectrometry was used to demonstrate the link between source water characteristics (high organics, iron and manganese) and lead and copper in point of use drinking water.


Assuntos
Água Potável , Poluentes Químicos da Água , Canadá , Corrosão , Nunavut , Qualidade da Água , Abastecimento de Água
17.
Philos Trans A Math Phys Eng Sci ; 378(2181): 20190354, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32862818

RESUMO

Models incorporating seasonality are necessary to fully assess the impact of global warming on Arctic communities. Seasonal migrations are a key component of Arctic food webs that still elude current theories predicting a single community equilibrium. We develop a multi-season model of predator-prey dynamics using a hybrid dynamical systems framework applied to a simplified tundra food web (lemming-fox-goose-owl). Hybrid systems models can accommodate multiple equilibria, which is a basic requirement for modelling food webs whose topology changes with season. We demonstrate that our model can generate multi-annual cycling in lemming dynamics, solely from a combined effect of seasonality and state-dependent behaviour. We compare our multi-season model to a static model of the predator-prey community dynamics and study the interactions between species. Interestingly, including seasonality reveals indirect interactions between migrants and residents not captured by the static model. Further, we find that the direction and magnitude of interactions between two species are not necessarily accurate using only summer time-series. Our study demonstrates the need for the development of multi-season models and provides the tools to analyse them. Integrating seasonality in food web modelling is a vital step to improve predictions about the impacts of climate change on ecosystem functioning. This article is part of the theme issue 'The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.


Assuntos
Migração Animal , Cadeia Alimentar , Modelos Biológicos , Tundra , Animais , Regiões Árticas , Arvicolinae , Biomassa , Raposas , Gansos , Aquecimento Global , Nunavut , Estações do Ano , Estrigiformes
18.
J Cross Cult Gerontol ; 35(2): 133-153, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32409899

RESUMO

This paper explores perspectives of Inuit elders on the relationships between aging, health and place. Their views are important to consider in the context of a growing proportion and number of older people in Arctic communities, a new sociological condition. Developing policies and programs to promote healthy aging in Inuit communities is challenging as there is little known about the social and living conditions that promote healthy aging in the Arctic. In this study twenty Inuit aged between 50 to 86, from one community in Nunavut, participated to in-depth qualitative interviews. Themes discussed included aging and health, housing conditions, community conditions, land-based activities, medical and leisure travel outside of the community, and mobility and accessibility. Preliminary analyses of the qualitative data were validated in the community through a focus group with four participants and an interpreter. Interviews and the focus group transcripts were analysed using thematic content analyses and NVivo 12 qualitative data analysis program (QSR International Pty Ltd. 2017). Participants reported that spending time with children, having social support, living in houses adapted to aging health conditions, having access to community activities and services, and time spent on the land were the main resources supporting their health. Several factors limited the availability of these resources. These include: lack of accessibility to resources; structural factors impacting their availability; and natural and social changes in interpersonal relationships. Participants also stressed the importance of being able to grow old in their own community. Knowledge generated in this project contributes to policies and programs targeting housing and community conditions to support healthy aging, and aging in place, in Inuit Nunangat.


Assuntos
Envelhecimento/psicologia , Envelhecimento Saudável/psicologia , Vida Independente/psicologia , Inuíte/psicologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Grupos Focais , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Nunavut , Pesquisa Qualitativa , Determinantes Sociais da Saúde , Apoio Social
19.
CMAJ ; 191(20): E552-E558, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113784

RESUMO

BACKGROUND: Household food insecurity, a measure of income-related problems of food access, is a pressing public health problem in Canada's North, especially in Nunavut. We aimed to assess the impact of Nutrition North Canada, a food retail subsidy intended to improve food access and affordability in isolated communities, on household food insecurity in Nunavut. METHODS: Using data from 3250 Nunavut households sampled in the annual components of the Canadian Community Health Survey (2007 to 2016), we conducted interrupted time series regression analyses to determine whether the introduction of Nutrition North Canada was associated with changes in the rates of self-reported food insecurity, according to a validated instrument. We used propensity score weighting to control for several sociodemographic characteristics associated with food insecurity. RESULTS: Food insecurity affected 33.1% of households in 2010 (the year before the launch of Nutrition North Canada), 39.4% of households in 2011 (the year of the launch) and 46.6% of households in 2014 (the year after full implementation). After controlling for several covariates, we found the rate of food insecurity increased by 13.2 percentage points (95% confidence interval [CI] 1.7 to 24.7) after the full implementation of the subsidy program, and the increase in food insecurity first occurred in 2011 (9.6 percentage points, 95% CI 2.7 to 16.4), the year Nutrition North Canada was launched. INTERPRETATION: Food insecurity was a pervasive problem in Nunavut before Nutrition North Canada, but it has become even more prevalent since the program was implemented. Given the important health consequences of food insecurity, more effective initiatives to address food insecurity in Canada's North are urgently needed.


Assuntos
Assistência Alimentar/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Comércio/estatística & dados numéricos , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nunavut , Estado Nutricional , Fatores Socioeconômicos , Adulto Jovem
20.
Environ Sci Technol ; 53(18): 10753-10762, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31412696

RESUMO

The delivery of perfluoroalkyl substances (PFAS) from snowpacks into Lake Hazen, located on Ellesmere Island (Nunavut, Canada, 82° N) indicates that annual atmospheric deposition is a major source of PFAS that undergo complex cycling in the High Arctic. Perfluoroalkyl carboxylic acids (PFCA) in snowpacks display odd-even concentration ratios characteristic of long-range atmospheric transport and oxidation of volatile precursors. Major ion analysis in snowpacks suggests that sea spray, mineral dust, and combustion aerosol are all relevant to the fate of PFAS in the Lake Hazen watershed. Distinct drifts of light and dark snow (enriched with light absorbing particles, LAPs) facilitate the study of particle loads on the fate of PFAS in the snowpack. Total PFAS (ΣPFAS, ng m-2) loads are lower in snowpacks enriched with LAPs and are attributed to reductions in snowpack albedo combined with enhanced post-depositional melting. Elevated concentrations of PFCA are observed in the top 5 m of the water column during snowmelt periods compared to ice-covered or ice-free periods. PFAS concentrations in deep waters of the Lake Hazen water column were consistent between snowmelt, ice-free, and ice-covered periods, which is ascribed to the delivery of dense and turbid glacier meltwaters mixing PFAS throughout the Lake Hazen water column. These observations highlight the underlying mechanisms in PFAS cycling in High Arctic Lakes particularly in the context of increased particle loads and melting.


Assuntos
Fluorocarbonos , Lagos , Regiões Árticas , Canadá , Monitoramento Ambiental , Nunavut
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