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1.
Ecol Evol ; 14(8): e11581, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39114172

ABSTRACT

Piping plovers (Charadrius melodus sp.) rank among North America's most endangered shorebird species, facing compounding environmental challenges that reduce habitat availability and suppress recruitment and survival rates. Despite these challenges, research on the direct effects of climate variability and extremes on their breeding ecology remains limited. Here, we employ a spatiotemporal modelling approach to investigate how location, nest timing and weather conditions influence reproductive success rates in a small breeding population of C. m. melodus in Prince Edward Island (PEI), Canada from 2011 to 2023. Analysis of 40 years of monitoring records from a subset of nesting sites revealed that flooding and predation have been persistent sources of reproductive failures in this population, with unexplained losses increasing in recent years. Contrary to our hypotheses, our modelled results did not support a negative impact of extreme high temperatures and strong precipitation events on reproductive outcomes. Instead, we identified a positive effect of T MAX and no effect of strong precipitation, perhaps due to limited exposure to extreme high temperatures (>32°C) and context-specific risks associated with precipitation-induced flooding. However, trends in regional climate change are likely to increase exposure to-and the influence of-such factors in the near future. Our models also identified spatiotemporal variability in apparent hatch success over the study period, as well as worse hatch outcomes across popular beachgoing regions and for delayed nesting attempts. While our results offer preliminary insights into factors affecting breeding success in this population, further research will be imperative to enhance understanding of constraints on recruitment. To this end, we encourage the collection and analysis of additional time-series data of prey populations, human activities, fine-scale weather data and predator/flood risks associated with each nest on PEI.

2.
Vet Med Sci ; 10(4): e1530, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38979670

ABSTRACT

AIM: This study aimed to summarize the frequency and the antimicrobial susceptibility profiles of the Salmonella serotypes identified from the specimens of companion animals, livestock, avian, wildlife and exotic species within Atlantic Canada. MATERIALS AND METHODS: The retrospective electronic laboratory data of microbiological analyses of a selected subset of samples from 03 January 2012 to 29 December 2021 submitted from various animal species were retrieved. The frequency of Salmonella serotypes identified, and their antimicrobial susceptibility results obtained using the disk diffusion or broth method were analysed. The test results were interpreted according to the Clinical and Laboratory Standards Institute standard. The Salmonella serotypes were identified by slide agglutination (Kauffman-White-Le-Minor Scheme) and/or the Whole Genome Sequencing for the Salmonella in silico Serovar Typing Resource-based identification. RESULTS: Of the cases included in this study, 4.6% (n = 154) had at least one Salmonella isolate, corresponding to 55 different serovars. Salmonella isolation was highest from exotic animal species (n = 40, 1.20%), followed by porcine (n = 26, 0.78%), and canine (n = 23, 0.69%). Salmonella subsp. enterica serovar Typhimurium was predominant among exotic mammals, porcine and caprine samples, whereas S. Enteritidis was mostly identified in bovine and canine samples. S. Typhimurium of porcine origin was frequently resistant (>70.0%) to ampicillin. In contrast, S. Typhimurium isolates from porcine and caprine samples were susceptible (>70.0%) to florfenicol. S. Oranienburg from equine samples was susceptible to chloramphenicol, but frequently resistant (>90.0%) to azithromycin. In avian samples, S. Copenhagen was susceptible (>90.0%) to florfenicol, whereas Muenchen was frequently resistant (>90.0%) to florfenicol. S. subsp. diarizonae serovar IIIb:61:k:1,5 of ovine origin was resistant (50.0% isolates) to sulfadimethoxine. No significant changes were observed in the antibiotic resistance profiles across the study years. CONCLUSIONS: This report provides data for surveillance studies, distribution of Salmonella serotypes and their antimicrobial resistance among veterinary specimens of Atlantic Canada.


Subject(s)
Salmonella Infections, Animal , Salmonella , Serogroup , Animals , Retrospective Studies , Salmonella/drug effects , Salmonella/isolation & purification , Salmonella/genetics , Salmonella/classification , Salmonella Infections, Animal/microbiology , Salmonella Infections, Animal/epidemiology , Animals, Wild/microbiology , Canada/epidemiology , Livestock/microbiology , Anti-Bacterial Agents/pharmacology , Pets/microbiology , Birds/microbiology , Microbial Sensitivity Tests/veterinary
3.
Mar Pollut Bull ; 202: 116352, 2024 May.
Article in English | MEDLINE | ID: mdl-38604080

ABSTRACT

Artificial light at night (ALAN) is becoming a widespread stressor in coastal ecosystems, affecting species that rely on natural day/night cycles. Yet, studies examining ALAN effects remain limited, particularly in the case of sessile species. This study assessed the effects of ALAN upon the feeding activity and two molecular indicators in the widespread plumose sea anemone Metridium senile. Anemones were exposed to either natural day/night or ALAN conditions to monitor feeding activity, and tissue samples were collected to quantify proteins and superoxide dismutase (SOD) enzyme concentrations. In day/night conditions, sea anemones showed a circadian rhythm of activity in which feeding occurs primarily at night. This rhythm was altered by ALAN, which turned it into a reduced and more uniform pattern of feeding. Consistently, proteins and SOD concentrations were significantly lower in anemones exposed to ALAN, suggesting that ALAN can be harmful to sea anemones and potentially other marine sessile species.


Subject(s)
Light , Sea Anemones , Superoxide Dismutase , Animals , Sea Anemones/physiology , Superoxide Dismutase/metabolism , Feeding Behavior , Circadian Rhythm
4.
Cancers (Basel) ; 15(19)2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37835419

ABSTRACT

Globally, cutaneous melanoma (CM) incidence is increasing, with sun exposure identified as a key modifiable risk factor. The Atlantic provinces of Canada display varied CM incidence rates: New Brunswick aligns with the national average, while Nova Scotia and Prince Edward Island exceed it, and Newfoundland and Labrador fall below this benchmark. We investigated the relationship between sun exposure and CM in these provinces. Twenty-two focus groups encompassing 95 Atlantic Canada residents were conducted and transcribed. A thematic analysis was conducted in MAXQDA using the social-ecological model as a framework. Residents of high-CM incidence provinces demonstrated greater sun exposure awareness, consulting UV indices, and using sunscreen and sun-protective clothing. However, they received greater UV exposure due to warmer climates and outdoor work and cultural activities. Conversely, those in low-incidence provinces used sunscreen and sun-protective clothing less often, engaged in occupations and hobbies affording less sun exposure, and lived in cooler climates. Our data supports a possible "sunscreen paradox", whereby increased sunscreen use is correlated with augmented sun exposure, leading to a deceptive sense of security. Public health initiatives in Atlantic Canada promoting sun safety must address this paradox while integrating community-specific behaviors and norms in order to develop tailored campaigns.

5.
J Theor Biol ; 561: 111378, 2023 03 21.
Article in English | MEDLINE | ID: mdl-36584747

ABSTRACT

During the COVID-19 pandemic, some countries, such as Australia, China, Iceland, New Zealand, Thailand, and Vietnam successfully implemented an elimination strategy, enacting strict border control and periods of lockdowns to end community transmission. Atlantic Canada and Canada's territories implemented similar policies, and reported long periods with no community cases. In Newfoundland and Labrador (NL), Nova Scotia, and Prince Edward Island a median of 80% or more of daily reported cases were travel-related from July 1, 2020 to May 31, 2021. With increasing vaccination coverage, it may be appropriate to exit an elimination strategy, but most existing epidemiological frameworks are applicable only to situations where most cases occur in the community, and are not appropriate for regions that have implemented an elimination strategy. To inform the pandemic response in regions that are implementing an elimination strategy, we extend importation modelling to consider post-arrival travel restrictions, and pharmaceutical and non-pharmaceutical interventions in the local community. We find that shortly after the Omicron variant had begun spreading in Canada, the expected daily number of spillovers, infections spread to NL community members from travellers and their close contacts, was higher than any time previously in the pandemic. By December 24, 2021, the expected number of spillovers was 44% higher than the previous high, which occurred in late July 2021 shortly after travel restrictions were first relaxed. We develop a method to assess the characteristics of potential future community outbreaks in regions that are implementing an elimination strategy. We apply this method to predict the effect of variant and vaccination coverage on the size of hypothetical community outbreaks in Mount Pearl, a suburb of the St. John's metropolitan area in NL. Our methodology can be used to evaluate alternative plans to relax public health restrictions when vaccine coverage is high in regions that have implemented an elimination strategy. This manuscript was submitted as part of a theme issue on "Modelling COVID-19 and Preparedness for Future Pandemics".


Subject(s)
COVID-19 , Humans , COVID-19/epidemiology , COVID-19/prevention & control , SARS-CoV-2 , Pandemics/prevention & control , Travel , Communicable Disease Control , Travel-Related Illness
6.
Mar Pollut Bull ; 184: 114147, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36152494

ABSTRACT

The influence of artificial light at night (ALAN) is becoming evident in marine sandy beaches. These habitats are dominated by species reliant on natural daylight/night regimes, making the identification of biological indicators a priority. We assessed the applicability of hemocyanin, an oxygen-transport protein in the hemolymph of many invertebrates, as an indicator of ALAN-related stress. Unlike total proteins, hemocyanins signal metabolic function and stress, so we expected them to increase in response to ALAN. We adapted spectrophotometry protocols to describe spatial variation in hemocyanins and total proteins in four populations of the talitroid amphipod Americorchestia longicornis. Then, a two-week experiment tested for changes in response to ALAN. Hemocyanin levels increased by 17 % and 40 % with respect to experimental controls after 7 and 14 d, respectively, and were higher than any measurements conducted in the field. These results suggest good prospects for hemocyanin as an indicator of ALAN effects.


Subject(s)
Amphipoda , Animals , Hemocyanins , Environmental Biomarkers , Light Pollution , Oxygen , Carrier Proteins , Light
7.
Emerg Infect Dis ; 28(6): 1292-1294, 2022 06.
Article in English | MEDLINE | ID: mdl-35608954

ABSTRACT

In July 2021, a PCR-confirmed case of locally acquired Babesia microti infection was reported in Atlantic Canada. Clinical features were consistent with babesiosis and resolved after treatment. In a region where Lyme disease and anaplasmosis are endemic, the occurrence of babesiosis emphasizes the need to enhance surveillance of tickborne infections.


Subject(s)
Anaplasma phagocytophilum , Anaplasmosis , Babesia microti , Babesiosis , Borrelia burgdorferi , Ixodes , Lyme Disease , Anaplasmosis/diagnosis , Anaplasmosis/drug therapy , Anaplasmosis/epidemiology , Animals , Babesiosis/diagnosis , Babesiosis/drug therapy , Babesiosis/epidemiology , Canada/epidemiology , Lyme Disease/diagnosis , Lyme Disease/epidemiology
8.
Vet Sci ; 9(4)2022 Mar 25.
Article in English | MEDLINE | ID: mdl-35448657

ABSTRACT

Bacterial infection and antimicrobial resistance are important constraints in the production and sustainability of farmed salmonids. This retrospective study aimed to describe the frequency of bacterial isolates and antimicrobial resistance profiles in salmonid aquaculture in Atlantic Canada. Bacterial isolates and antimicrobial susceptibility testing (AST) results assessed by disk diffusion testing were summarized for 18,776 Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) samples from 2291 unique cases submitted to the Atlantic Veterinary College, Aquatic Diagnostic Services Bacteriology Laboratory from 2000 to 2021. Kidney was the most commonly submitted tissue (60.29%, n = 11,320), and these specimens were mostly submitted as swabs (63.68%, n = 11,957). The most prevalent pathogens detected in these cases were Yersinia ruckeri type 1 (5.54%, n = 127), Renibacterium salmoninarum (2.10%, n = 48), Aeromonas salmonicida (atypical) (1.66%, n = 38), and Pseudomonas fluorescens (1.22%, n = 28). Most bacterial isolates tested (n = 918) showed resistance to florfenicol, oxytetracycline, ormetoprim-sulfadimethoxine, and trimethoprim-sulfamethoxazole, but not to enrofloxacin. This report provides baseline data for antimicrobial surveillance programs that investigate emerging antimicrobial resistance trends in salmonid aquaculture in Atlantic Canada.

9.
J Fish Dis ; 45(6): 919-930, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35397120

ABSTRACT

An incursion of infectious salmon anaemia virus (ISAV) was detected in 2020 in southern Newfoundland, Canada. This resulted in an outbreak affecting four marine farms stocking Atlantic salmon (Salmo salar L.) vaccinated against ISAV. This study provides the first description of epidemiologic characteristics of an ISAV outbreak in 2020 and 2021, and detected ISAV variants at the population level. Fish kidneys were screened for ISAV by real-time RT-PCR and non-negative samples were submitted for genotyping and further diagnostic testing. Nine distinct ISAV variants were identified: five European and three North American (NA) HPRΔ ISAV, and one NA-HPR0 ISAV variant. A notable finding was the concurrent detection of both an HPR0 and an HPRΔ ISAV variant in one individual fish. In two farms, both European and NA variants were simultaneously detected, while in the other two farms either NA or European variants were identified, but not both together. Generally, mortality increases followed rises in ISAV prevalence and cycle threshold values on RT-PCR decreased with time. Epidemiologic descriptions of ISAV outbreaks in Atlantic Canada contributes to the understanding of local disease dynamics and identification of changes thereof. Such insights are essential for the strengthening of disease management plans.


Subject(s)
Fish Diseases , Isavirus , Orthomyxoviridae Infections , Salmo salar , Animals , Canada , Fish Diseases/epidemiology , Isavirus/genetics , Newfoundland and Labrador , Orthomyxoviridae Infections/epidemiology , Orthomyxoviridae Infections/veterinary , Phylogeny
10.
Front Sociol ; 6: 655880, 2021.
Article in English | MEDLINE | ID: mdl-34746294

ABSTRACT

Researchers, policymakers, and the public often claim that "extreme" political views have become increasingly commonplace and that polarization on issues of race and immigration has become a central dilemma for contemporary politics. The popular narrative of political polarization captures tensions that many are noticing and experiencing. However, there is also significant confusion around the concept, as well as gaps between popular perceptions and empirical findings on the different forms of polarization and their prevalence across regions. It is unclear to what extent polarization describes a global phenomenon, as its national and subnational manifestations vary considerably, produced from distinct local histories as well as diffuse transnational forces. While the United States is often treated as ground zero for political polarization, nearby Canada does not appear to be experiencing polarization to nearly the same degree. Using data from a 2019 survey on Atlantic Canadians' political views and perceptions of change, this paper examines whether underlying forms of political polarization are manifesting in the region. We assess whether mass ideological polarization and partisan sorting can be found in Atlantic Canada, looking at socio-cultural and economic dimensions of political values. We also examine perceptions of polarization in the region, using Multiple Correspondence Analysis to observe underlying associations between perceptions, extreme or polarized views, and partisanship. This mapping approach provides insight into latent patterns often missed by more traditional methods.

11.
Healthcare (Basel) ; 9(10)2021 Oct 10.
Article in English | MEDLINE | ID: mdl-34683024

ABSTRACT

This research aims to identify the influence of woman leadership on improving the traditional man-dominated scientific-political communication towards positive COVID-19-driven public health interventions. Across Canada, dual-gendered leadership (women chief medical officers and men prime minister/premiers) at both federal and provincial levels illustrated a positive approach to "flatten the curve" during the first and second waves of COVID-19. With the four provinces of New Brunswick, Newfoundland and Labrador, Nova Scotia, and Prince Edward Island, Atlantic Canada formed the "Atlantic Bubble", which has become a great example domestically and internationally of successfully mitigating the pandemic while maintaining societal operation. Three provinces have benefitted from this complementary dual-gendered leadership. This case study utilized a scoping media coverage review approach, quantitatively examining how gender-inclusive scientific-political cooperation supported effective provincial responses in Atlantic Canada during the first two waves of COVID-19. This case study discovers that (1) at the provincial government level, woman leadership of mitigation, advocating, and coordination encouraged provincial authorities to adapt science-based interventions and deliver consistent and supportive public health information to the general public; and (2) at the community level, this dual-gendered leadership advanced community cohesion toward managing the community-based spread of COVID-19. Future studies may apply a longitudinal, retrospective approach with Canada-wide or cross-national comparison to further evaluate the strengths and weaknesses of dual-gendered leadership.

12.
Soc Sci Med ; 279: 113947, 2021 06.
Article in English | MEDLINE | ID: mdl-33991791

ABSTRACT

INTRODUCTION: Indigenous communities across Canada report that transformations in Indigenous health research are needed, where the benefits of research shift intentionally, collaboratively, and with transparency from the researchers directly to Indigenous communities and partners. Despite its challenges and potential for harm, research, if done ethically and with respect and partnership, can be a force for change and will strengthen the efficacy of data on Indigenous Peoples' health and wellbeing. PURPOSE: To characterize the nature, range, and extent of Indigenous health research in Atlantic Canada, and to identify gaps. METHODS: Eleven databases were searched using English-language keywords that signify Indigeneity, geographic regions, health, and Indigenous communities in Atlantic Canada between 2001 and May 2020. All references were reviewed independently by two reviewers. Of the 9056 articles identified, 211 articles were retained for inclusion. Data were extracted using a collaboratively developed data charting form. RESULTS: Indigenous health research in Atlantic Canada has increased over time, covering a diverse range of health topics. The main areas of research included climate change, child and youth health, and food and water security, with the majority of research deriving from Newfoundland and Labrador. Rates of reported community engagement remain relatively low and steady between 2001 and 2020, however there was an increase in researchers seeking Indigenous ethics approvals for such engagement. CONCLUSIONS: This scoping review synthesizes 20 years of Indigenous health research in Atlantic Canada. The results indicate that although there are increases in Indigenous ethics approvals, there is more work needed to ensure that Indigenous Peoples lead, design, and benefit from research conducted in their homelands.


Subject(s)
Indigenous Peoples , Population Groups , Adolescent , Canada , Child , Humans , Newfoundland and Labrador , Surveys and Questionnaires
13.
Front Sociol ; 6: 578647, 2021.
Article in English | MEDLINE | ID: mdl-33869545

ABSTRACT

In Canada, interprovincial labor migration is a common form of mobile work that is significant for rural communities especially in Atlantic Canada. Unique to this form of labor migration is the gendered nature of the phenomenon resulting in men often leaving their wives, families and rural communities behind for employment opportunities in the oil and gas sectors thousands of kilometers away. As men leave their families and communities for employment, women who are left behind become primary caregivers to children in addition to also being the primary caretakers of the family home. The Tale of Two Islands project was a multi-year, cross regional mixed methods research study that examined labor mobility and its impact on families and communities. This paper examines how labor migration has impacted families and rural communities. Drawing upon focus group, conversational and key informant interviews with families impacted by mobile labor and practitioners who serve them, societal perceptions of gendered norms and perceptions of rural life became illuminated. This has contributed to multiple contradictions and role confusion as families adapt and adjust to periods of reunification and separation while striving to remain connected to their rural communities. Men yearn for opportunities to be an active member of their home communities but cannot a result of living away for extended periods of time. In contrast, women who stay behind in rural communities often chose to isolate from community activities as a result of perceived judgments that are attributed to traditional views of rural life and family roles.

14.
Mar Pollut Bull ; 163: 111928, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33418341

ABSTRACT

Human growth has caused an unprecedented increase in artificial light at night (ALAN). In coastal habitats, many species rely on day/night cycles to regulate various aspects of their life history and these cycles can be altered by this stressor. This study assessed the influence of ALAN on the early (cyprid) and late (spat) settlement stages of the acorn barnacle Semibalanus balanoides, a species widely distributed in natural and man-made coastal habitats of the North Atlantic. A newly designed settlement plate, originally for studies in rocky intertidal habitats in the southeast Pacific, was adapted to measure settlement rates on man-made habitats -wharf seawalls- located in Atlantic Canada. Plates equipped with a small LED diode powered by an internal battery (ALAN plates) were used to quantify settlement rates in comparison to plates lacking a light source (controls). These plates were deployed for 6 d in the mid-intertidal levels, where adult barnacles were readily visible. ALAN and control plates collected large number of settlers and showed to be suitable for this type of man-made habitats. The number of early settlers (cyprids) did not differ between plates but the number of late settlers (spat) was significantly lower in ALAN plates than in controls. These results suggest that light pollution has little influence on the early stages of the acorn barnacle settlement but is clearly detrimental to its late stages. As barnacles dominate in many natural and man-made hard substrates, it is likely that ALAN also has indirect effects on community structure.


Subject(s)
Thoracica , Animals , Canada , Ecosystem , Environmental Pollution , Humans , Light , Seafood
15.
J Assoc Med Microbiol Infect Dis Can ; 6(3): 213-220, 2021 Sep.
Article in English | MEDLINE | ID: mdl-36337757

ABSTRACT

Background: Jamestown Canyon virus (JCV) and snowshoe hare virus (SSHV) are wide-ranging mosquito-borne arboviruses in the California serogroup viruses (CSGV) that are known to circulate in New Brunswick. Despite potential for debilitating central nervous system manifestations, the prevalence of human exposure to these viruses in New Brunswick is unknown. The goal of this study was to quantify rates of human exposure in New Brunswick to these neglected arboviruses. Methods: A retrospective, anonymized provincial serosurvey was performed using a stratified random sample of residual sera submitted between May 2015 and August 2016. To determine the seroprevalence of JCV and SSHV, competitive enzyme-linked immunosorbent assay-positive samples were confirmed positive using plaque-reduction neutralization testing (PRNT). Results: A total of 452 serum samples were screened. The seroprevalence of antibodies against CSGV was estimated to be 31.6% (95% CI 27.4% to 36.1%) with 143 positive samples. PRNT results indicated that most single virus exposures were due to JCV (38 of 143; 26.6%) rather than SSHV (3 of 143; 2.1%). The species of CSGV, to which the remaining 102 seropositive people were exposed, could not be precisely determined. Conclusions: The prevalence of human exposure to CSGV is high but comparable to rates observed in other Atlantic Canadian jurisdictions. Studies such as this provide important baseline epidemiological data regarding the risk of exposure to these neglected arboviruses. SSHV and JCV should be considered in the differential diagnosis for undiagnosed febrile and neuroinvasive illness during mosquito season, particularly when testing for common aetiologies is negative or inconclusive.


Historique : Le virus de Jamestown Canyon (VJC) et le virus du lièvre d'Amérique (VLA) sont des arbovirus à grande portée transmis par des moustiques des virus du sérogroupe Californie (VSGC) qui circulent au Nouveau-Brunswick (NB). Malgré le risque de manifestations débilitantes du système nerveux central, on ne connaît pas la prévalence d'exposition humaine à ces virus au NB. La présente étude visait à quantifier le taux d'exposition humaine à ces arbovirus négligés au NB. Méthodologie : Les chercheurs ont réalisé une enquête sérologique rétrospective provinciale anonymisée au moyen d'un échantillon randomisé stratifié de sérum résiduel soumis entre mai 2015 et août 2016 au dépistage systématique. Ils ont stratifié le processus de sélection selon l'âge, le sexe et la zone de santé régionale afin de garantir un échantillonnage proportionné. Pour déterminer la séroprévalence du VJC et du VLA, ils ont confirmé la positivité des résultats d'échantillons positifs au test ELISA au moyen de tests de séroneutralisation par réduction des plaques (TSRP). Résultats : Au total, 452 échantillons de sérum ont fait l'objet d'un dépistage. Au NB, la séroprévalence des anticorps anti-VSGC était évaluée à 31,6 % (IC à 95 %, 27,4 % à 36,1 %), pour 143 échantillons positifs. Selon les résultats du TSRP, la plupart des expositions à un seul virus étaient causées par le VJC (38 cas sur 143, 26,6 %) plutôt qu'au VLA (trois cas sur 143, 2,1 %). Les espèces de VSGC, auxquelles les 102 autres personnes séropositives ont été exposées, n'ont pas pu être établies avec précision. Conclusions : La prévalence d'exposition humaine au VSGC est élevée, mais comparable aux taux observés dans d'autres régions des provinces de l'Atlantique. Des études comme celle-ci fournissent des données épidémiologiques de référence importantes à l'égard du risque d'exposition humaine à ces arbovirus négligés. Il faut tenir compte du VLA et du VJC dans le diagnostic différentiel de maladie fébrile et neuro-invasive pendant la saison des moustiques, notamment lorsque les tests pour dépister d'autres étiologies courantes sont négatifs ou non concluants.

16.
Ecol Evol ; 8(15): 7334-7345, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30151153

ABSTRACT

Insect outbreaks are major natural disturbance events that affect communities of forest birds, either directly by affecting the food supply or indirectly by changing the vegetation composition of forest canopies. An examination of correlations between measures of bird and insect abundance across different spatial scales and over varying time lag effects may provide insight into underlying mechanisms. We developed a hierarchical Bayesian model to assess correlations between counts of eight warbler species from the Breeding Bird Survey in eastern Canada, 1966 to 2009, with the presence of spruce budworm (Choristoneura fumiferana Clem.) at immediate local scales and time-lagged regional scales, as measured by extent of defoliation on host tree species. Budworm-associated species Cape May warbler (Setophaga tigrina), bay-breasted warbler (Setophaga castanea), and Tennessee warbler (Oreothlypis peregrina) responded strongly and positively to both local and regional effects. In contrast, non-budworm-associated species, Blackburnian warbler (Setophaga fusca), magnolia warbler (Setophaga magnolia), Canada warbler (Cardellina canadensis), black-throated blue warbler (Setophaga caerulescens), and black-throated green warbler (Setophaga virens), only responded to regional effects in a manner that varied across eastern Canada. The complex responses by forest birds to insect outbreaks involve both increased numerical responses to food supply and to longer term responses to changes in forest structure and composition. These effects can vary across spatial scales and be captured in hierarchical population models, which can serve to disentangle common trends from data when examining drivers of population dynamics like forest management or climate change.

17.
Mar Pollut Bull ; 127: 160-164, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29475649

ABSTRACT

Tethering assays, or the physical restraint of test organisms, has been used in the past to measure selected organisms' response to stressors while removing the observer from the experimental setting. Although informative for monitoring and hypothesis testing, these assays often used microfilaments that have been found to be too invasive or prone to biases given their effects on test organisms' behavior. Here, we describe a new variation of tethering using American oysters (Crassostrea virginica) and illustrate its use in the study of their mortality rates as a result of two stressors: siltation and predation by a non-indigenous species. Our protocol identified a resistant (non-toxic) glue that could be used to attach oysters to stone slabs, thus partially mimicking the natural cementation of the shell to natural substrates. This variation of tethering was harmless and maintained oysters' body position and natural ability to filter feed. Using tethered oysters in separate two-week field cage experiments, we also show how siltation and predation by a non-indigenous species (the European green crab, Carcinus maenas), caused a gradual, easily measurable increase in oyster mortality rates. We argue that this variation of tethering is a cost-effective and advantageous way to monitor or test the effects of these and other stressors on oysters and similar species.


Subject(s)
Behavior, Animal/physiology , Crassostrea/physiology , Environmental Monitoring/methods , Introduced Species , Restraint, Physical/physiology , Stress, Physiological , Animals , Brachyura/physiology , Crassostrea/growth & development , Predatory Behavior/physiology , Survival Analysis , United States
18.
J Fish Dis ; 41(3): 421-430, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28782809

ABSTRACT

The infectious salmon anaemia virus (ISAV) is an important viral disease of farmed Atlantic salmon that has caused considerable financial losses for salmon farmers around the world, including Atlantic Canada. It is listed as a notifiable disease by the World Organization for Animal Health, and to this day, culling of infected cages or farms remains the current practice in many countries to mitigate the spread of the virus. In Atlantic Canada, ISAV was first detected in 1996 and continues to be detected. While some outbreaks seemed to have arisen from isolated infections of unknown source, others were local clusters resulting from horizontal spread of infection. This study provides a description of the detected ISAV isolates in Atlantic Canada between 2012 and 2016, and explores the phylogenetic relatedness between these ISAV isolates. A key finding is the detection for the first time of a North American-HPR0 ISAV subtype, which was predicted to exist for many years. Through phylogenetic analysis, a scenario emerges with at least three separate incursions of ISAV in Atlantic Canada. An initial ISAV introduction follows a genotypic separation between North America and Europe which resulted in the NA and EU genotypes known today; this separation predates the salmon aquaculture industry. The second incursion of ISAV from Europe to North America led to a sublineage in Atlantic Canada consisting of EU-HPR∆ isolates detected in Nova Scotia and New Brunswick, and the predominant form of ISAV-HPR0 (EU). Finally, we observed what could be the third and most recent incursion of ISAV in Newfoundland, in the form of an isolate highly similar to ISAV EU-HPR0 isolates found in the Faroe Islands and the one isolate from Norway.


Subject(s)
Fish Diseases/virology , Genotype , Isavirus/physiology , Orthomyxoviridae Infections/veterinary , Salmon , Viral Proteins/genetics , Amino Acid Sequence , Animals , Canada , Isavirus/classification , Isavirus/genetics , Orthomyxoviridae Infections/virology , Phylogeny , Phylogeography , Sequence Alignment , Viral Proteins/chemistry , Viral Proteins/metabolism
19.
Can Liver J ; 1(3): 107-114, 2018.
Article in English | MEDLINE | ID: mdl-35991321

ABSTRACT

Background: Despite growing awareness of the significant burden of disease caused by hepatitis C virus (HCV) infection worldwide, understanding of the epidemiology and demographic distribution of HCV infection in Canada, specifically in Atlantic Canada, is limited. Currently, data on the demographic and clinical profile of HCV-infected individuals in Newfoundland and Labrador is limited. The aim of this study is to address this knowledge gap. Methods: A retrospective cohort study of HCV-positive individuals referred for specialized care in St. John's, Newfoundland, between 1996 and 2014, was conducted. Descriptive data were obtained through chart review and access to a database consisting of individuals referred for specialized HCV care in St. John's. Results: During the study period, 767 individuals were referred for specialized HCV care, of whom 714 were included in our analysis. These individuals represent 57.5% of HCV-positive cases identified by the province's public health department during the same time frame. HCV infection was more common among men (68.2%) and urban dwellers (74.8%). The majority of cases were HCV genotype 1 (52.1%). Intravenous and intranasal drug use were the most common self-reported risk factors for HCV transmission. High loss-to-follow-up rates were found among those referred from the province's correctional system. Conclusions: This study provides important insights into the demographic and clinical profile of individuals referred for HCV-related care in Newfoundland and Labrador and fills a gap in the current understanding of HCV-positive individuals in this Atlantic province. These findings can help inform future directions for HCV-related health policy, resource allocation, and clinical care initiatives in Newfoundland and Labrador and across Canada.

20.
J Environ Manage ; 201: 252-259, 2017 Oct 01.
Article in English | MEDLINE | ID: mdl-28672197

ABSTRACT

Electricity generation from wind energy has proliferated throughout North America and will continue to grow. Given Canada's expected increase in wind energy capacity, consideration of the potential adverse impacts to bird and bat populations is prudent given their sensitivity to these projects. The province of Ontario, Canada is currently the leading jurisdiction for wind energy development, and for provincial guidance on pre- and post-construction monitoring. With uniform monitoring guidance in Ontario, wind energy proponents, and third-party consultants, have developed post-construction monitoring protocols that meet provincial guidance, while also providing standardized reporting. In Atlantic Canada, post-construction guidelines vary between provinces, depending mostly on guidance from the Environment Canada Canadian Wildlife Service and relevant provincial agencies. To ensure quality post-construction monitoring results in Atlantic Canada and other provinces, it is imperative that all Canadian provinces adopt similar approaches to those employed in Ontario. This paper reviews major causes of bird and bat mortalities; reviews Canadian federal and Ontario provincial bird and bat monitoring guidelines to elucidate gaps between environmental assessment (EA) theory and application; summarizes post-construction monitoring protocols from eight bird and bat post-construction monitoring programs used in Ontario; and, proposes recommendations to support future wind development opportunities across Canada and specifically in Atlantic Canada.


Subject(s)
Chiroptera , Energy-Generating Resources , Wind , Animals , Birds , Canada , Environmental Policy , North America , Ontario
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