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- OPEN ACCESSThe use of fossil moth wing scales has recently been introduced as a new method to reconstruct population histories of lepidopterans and provide a proxy for insect disturbance. We investigated the potential for using wing-scale ultrastructure to distinguish between the five most common outbreak species of moth pests in eastern North America: spruce budworm (Choristoneura fumiferana Clemens), hemlock looper (Lambdina fiscellaria Guenée), forest tent caterpillar (Malacosoma disstria Hübner), blackheaded budworm (Acleris variana Fernie), and jack pine budworm (Choristoneura pinus Freeman). Using scanning electron images of scales, we made qualitative and quantitative comparisons of morphological traits at the ultrastructural level. We found that hemlock looper and eastern blackheaded budworm scales could be categorically separated from each other and from the three other species. We developed a quadratic discriminant function using measurements of ultrastructure traits that distinguishes scales of the three remaining species with an overall accuracy of 66%. We found that forest tent caterpillar could be well separated based on these traits, but we were less confident in distinguishing the closely related jack pine and spruce budworm. Our method offers potential advantages in scale identification for future studies in paleoecology, while providing the additional advantage of not requiring intact, unfolded, and undamaged scales.
- OPEN ACCESSThe objective is to support development of a nutritional intervention for Chinese immigrants with diabetes by defining current deficiencies and identifying modifiable factors and mechanisms of change. Semi-structured interviews conducted with 13 ethnic Chinese with type 2 diabetes identified modifiable problems related to culturally relevant diabetes resources and low cultural acceptability of recommended diets. These factors could be addressed through creation of resources developed in partnership with Chinese-speaking health care professionals and persons with diabetes.
- OPEN ACCESSThe 31 March 2018 closure of the National Research Universal reactor marked the end of over 70 years of materials research using neutron beams from major neutron sources at the Chalk River Laboratories in Chalk River, Ontario, Canada. This closure will have a major impact on the Canadian materials research community, including researchers in the physics, chemistry, and engineering of materials. After a brief review of the history of neutron beams at the Chalk River Laboratories, we present the results of a bibliometric study of the scientific output of the research with neutron beams. In this study, we compiled a complete bibliographic record of the research papers beginning with the first neutron scattering experiments at the National Research Experimental reactor in 1947, analyzed the citations from 1980 onward, and benchmarked the results against major neutron beam facilities in other countries and against other major research facilities in Canada. We also conducted a broader bibliometric analysis of the use of neutron scattering data among all Canadians, regardless of where the data were taken. The results provide a useful metric of the size of the Canadian neutron scattering community and places into context the importance of access to this research tool.
- OPEN ACCESS
- Kim-Ly Thompson,
- Nikkita Reece,
- Nicole Robinson,
- Havana-Jae Fisher,
- Natalie C. Ban, and
- Chris R. Picard
Researchers and government agencies are increasingly embracing Indigenous knowledge to inform ecological monitoring. However, there are few detailed accounts of designing monitoring methods based in Indigenous knowledge to meet Indigenous objectives. This research details the design of a program initiated by the Gitga’at First Nation to document the knowledge and observations of their harvesters as a contemporary monitoring initiative. We, Gitga’at and academic researchers, first conducted informal interviews with knowledge holders to gauge interest and to establish community objectives. We then convened community meetings and workshops to design methods to document harvesters’ knowledge and observations. We tested and revised these methods (a post-harvest season interview guide, and a logbook to be completed by harvesters) over the course of two harvest seasons. Semi-structured interviews were more successful than the logbooks in meeting multiple community monitoring objectives. However, we were encouraged by younger participants’ suggestions to develop a digital app based on the logbook to encourage future participation. Our work can serve as a guide to other Indigenous peoples and collaborators who wish to leverage the knowledge of their land and (or) sea users, and the methods we develop are available to adapt to other cultural, social-ecological, and political contexts. - OPEN ACCESSAquaculture is one of the world’s fastest growing food production sectors and presents an opportunity for rural community development that can support coastal livelihoods. An ecosystem approach to aquaculture (EAA) has been recommended to facilitate socially and environmentally sustainable development, yet there remains a need to better involve people in planning and operational aspects. Community-based management may help to implement principles of the EAA; however, context-specific research is needed to understand its potential application and suitability. This research explores opportunities for community-based marine aquaculture (CBMA) for nonfinfish in the context of Nova Scotia, Canada, through a series of stakeholder interviews. Results suggest that all stakeholder groups interviewed were positive about the potential for CBMA to support sustainable aquaculture growth in the province; however, key questions around operationalizing CBMA remain. The aquaculture industry is on a continual path for growth worldwide and, therefore, it becomes increasingly important to proactively examine strategies such as CBMA that can help to facilitate EAA in a way that genuinely puts people at the centre of aquaculture development and governance.
- OPEN ACCESS
- Rosa H. Escobar-Lux,
- David M. Fields,
- Howard I. Browman,
- Steven D. Shema,
- Reidun M. Bjelland,
- Ann-Lisbeth Agnalt,
- Anne Berit Skiftesvik,
- Ole B. Samuelsen, and
- Caroline M.F. Durif
Hydrogen peroxide (H2O2), a pesticide used in salmonid aquaculture, is released directly into the environment where nontarget organisms are at risk of exposure. We determined threshold concentrations for mortality of Calanus spp., the dominant zooplankton species in the North Atlantic, and assessed sublethal effects, focusing on the escape response and oxygen consumption rates (OCRs) as behavioral and physiological assays. One-hour exposure to 170 mg·L−1 (i.e., 10% of the recommended H2O2 treatment) was lethal to copepodite stage V (92% mortality) and adult females (100% mortality). The acute median lethal concentration (1h-LC50) was 214.1 (150.67–277.4) and 48.6 (44.9–52.2) mg·L−1 for copepodite V and adults, respectively. The 25-h LC50 was 77.1 (57.9–96.2) and 30.63 (25.4–35.8) mg·L−1 for copepodite V and adults, respectively. At concentrations of 0.5% and 1% of the recommended treatment level, Calanus spp. showed a decrease in escape performance and lower OCRs with increased concentration. At H2O2 concentrations of 5% of the recommended treatment levels (85 mg·L−1), exposed copepods showed no escape reaction response. These results suggest that sublethal concentrations of H2O2 will increase the risk of predation for Calanus spp. Furthermore, this study provides supporting evidence that theoretical “safe” values, traditionally used for predicting toxicity thresholds, underestimate the impact of H2O2 on the physiological condition of nontarget crustaceans. - OPEN ACCESSFully 37% of species listed under Canada’s Species at Risk Act (SARA) are plants or lichens. The law does not automatically protect species on private land, and it is unknown how many at-risk plants grow mainly on private land. We analyzed official status reports and related documents for 234 plant species at risk to determine land tenure and evaluated differences in threats and changes in status. We also assessed how well plants were represented in two federal programs: the Natural Areas Conservation Program (NACP) and the Habitat Stewardship Program (HSP). Of SARA-listed plant species, 35% have the majority of their known populations on private land while <10% occur mostly on federal land. Species growing mainly on private land were no more or less likely to decline in status over time compared with others. Plant species at risk were less likely than other taxonomic groups to be found on land protected under the NACP. The proportion of HSP projects targeting plants is well below the expected proportion based on the number of listed species. We recommend that policy-makers promote and prioritize actions to increase the representation of plant species in federally funded programs, especially on private lands.
- OPEN ACCESSThe concept of health permeates priorities and policies for managing wild Pacific salmon (Oncorynchus spp.). Regulatory agencies rely largely on salmon abundance and (or) the absence of pathogens to declare if a population is healthy. Our goal was to determine if there was a receptive policy environment within Fisheries and Oceans Canada (DFO) to adopt a cumulative effects perspective of health. We used a previously developed health model along with a multiple streams framework and a narrative review of DFO policy to see how fish health was situated in DFO’s salmon management problems, policy, and politics. We discovered that a cumulative effects perspective was consistent with policy goals and priorities. DFO’s guiding principles and responsibilities for aquatic animal health were spread across multiple policies and regulations. There were no processes or people responsible for integrating information and activities. The use of the word health in policies and planning without a consistent definition meant that DFO could not explicitly assess if it has reached its management target of healthy salmon. An option for transitioning to cumulative effects perspective is to adopt a healthy public policy perspective and processes to integrate the diverse information linked to social and environmental determinants of health.
- OPEN ACCESSObjective: Females continue to participate in sport at lower rates than males. Girls who participate in sport gain many advantages. Even with programs designed to emphasize participation, some females continue with sport participation while others do not. Given the advantages and controversies surrounding testosterone and female sport, it is possible that testosterone may predispose females toward sport participation. Our objective was to determine if the second to fourth digit (2D:4D) ratio, a proxy for prenatal androgen exposure, correlates with sport participation throughout female adolescence and young adulthood. Methods: A cross-sectional analysis of indirect prenatal androgen exposure (i.e., 2D:4D) was completed on 18–30-year-old women (n = 92) using demographics, anthropometrics, sport-specific behaviour tendencies, and retrospective sport participation. Results: 2D:4D was not significantly correlated with total sport participation (TSP) (r = −0.065, p = 0.538). Secondary analyses revealed significant correlations between TSP and maximum hand grip (r = 0.406, p = 0.000) and the Sport Orientation Questionnaire (SOQcomp (r = 0.513475, p = 0.000), SOQgoal (r = 0.253, p = 0.015), SOQwin (r = 0.366, p = 0.000)). Conclusion: Although strength and competitiveness are strongly correlated with female sport participation, the impact of prenatal androgen exposure (i.e., 2D:4D) remains to be determined given its weak and negative association with female sport participation. Given that females participate in sport at lower rates than males, continuing to determine what factors influence sport participation is an important goal.
- OPEN ACCESS
An analysis of threats and factors that predict trends in Canadian vertebrates designated as at-risk
The identification of factors that predict trends in population abundance is critical to formulate successful conservation strategies. Here, we explore population trends of Canadian vertebrates assessed as “at-risk” by the Committee on the Status of Endangered Wildlife in Canada and the threats affecting these trends using data from the Canadian Living Planet Index. We investigate how threat profiles—the combination of threats for a given species—vary among species and taxonomic groups. We then investigate threat profile as a predictor of temporal trends—both exclusively and in combination with additional biotic and abiotic factors. Species had 5.06 (±2.77) threats listed on average, and biological resource use (BRU) was the most frequently cited. Our analysis also revealed an association between taxonomic group and population trends, as measured by the proportion of annual increases (years with a positive interannual change). By contrast, the predictive power of threat profile was poor. This analysis yielded some useful insight for conservation action, particularly the prioritization of abating BRU. However, the predictive models were not as meaningful as originally anticipated. We provide recommendations on methodological improvements to advance the understanding of factors that predict trends in population abundance for prioritizing conservation action. - OPEN ACCESSHarvest records suggest that the abundance of bobcats (Lynx rufus) has increased and the leading edge of their distribution has spread northward, while the trailing edge of the Canada lynx (Lynx canadensis) range has contracted in Ontario, Canada. There has been a debate about whether these closely related felids might compete in areas of sympatry, but there is little research on sympatric populations of bobcat and lynx. Both species are found on the north shore of Lake Huron in Ontario, Canada, which provided an opportunity to investigate their spatial patterns and habitat use. We surveyed snowmobile routes for snow tracks over three winters and estimated probability of occupancy for the two felid species while accounting for detectability. Bobcat and lynx tracks were never found on the same survey route. Bobcat occupancy increased with habitat heterogeneity, whereas lynx occupancy increased with homogeneity. Our results fit with the common assumption of the generalist and specialist natures of bobcat and lynx, respectively. Our findings suggest that bobcats invaded former lynx territory after these areas became vacant. The story of the bobcat and the lynx is one of the loss of a unique, boreal specialist due to anthropogenic change, and eventual replacement by an adaptable generalist.
- OPEN ACCESSShale-gas production could impact freshwater quality through contamination of the physical and chemical habitat (e.g., fracturing fluids, untreated or treated effluent) or development-related impacts. Despite environmental concerns, information is lacking to support biomonitoring as a diagnostic tool to assess impacts of shale-gas production. We characterized water quality and biota in areas of high shale gas potential (Early Carboniferous bedrock in New Brunswick, Canada) and surrounding geologic areas, and we assessed patterns in benthic macroinvertebrate (BMI) and fish assemblages. Early Carboniferous stations differed primarily based on water chemistry, and BMI were associated with a gradient in conductivity and temperature across geologic classes. Concordance analysis indicated similar classification of stations by both organism groups, though fish were more related to turbidity and nutrients. Concordance among fish and BMI was strongest at high conductivity, Early Carboniferous stations. These results suggest that geology plays a strong role in driving abiotic habitats and biotic communities of streams, even at small spatial scales. Furthermore, they suggest BMI and fish can provide complementary information for biomonitoring in shale-gas development areas, with BMI responding to increased ion concentrations from surface water contamination, and fish responding to changes in nutrients and turbidity resulting from development.
- OPEN ACCESS
- Jenny L. McCune,
- Sheila R. Colla,
- Laura E. Coristine,
- Christina M. Davy,
- D.T. Tyler Flockhart,
- Richard Schuster, and
- Diane M. Orihel
Pollution is a pervasive, albeit often invisible, threat to biodiversity in Canada. Currently, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) relies on expert opinion to assess the scope (i.e., the proportion of a species’ population that may be affected) of pollution to species at risk. Here, we describe a spatially explicit, quantitative method for assessing the scope of pollution as a threat to species at risk in Canada. Using this method, we quantified the geographic co-occurrence of 488 terrestrial and freshwater species and pollution sources and determined that, on average, 57% of the mapped occurrences of each species at risk co-occurred with at least one pollution source. Furthermore, we found a weak correlation between the scope of the threat of pollution as assessed by COSEWIC expert panels and the geographic overlap of species occurrences and pollution sources that we determined with our quantitative method. Experts frequently identified scope of pollution as absent or negligible even for species with extensive co-occurrence with pollution sources, especially vascular plants. Clearly, a quantitative approach is needed to make accurate estimates of the scope of pollution as a threat to species at risk in Canada. - OPEN ACCESS
- R. Drew Carleton,
- Emily Owens,
- Holly Blaquière,
- Stéphane Bourassa,
- Joseph J. Bowden,
- Jean-Noël Candau,
- Ian DeMerchant,
- Sara Edwards,
- Allyson Heustis,
- Patrick M.A. James,
- Alison M. Kanoti,
- Chris J.K. MacQuarrie,
- Véronique Martel,
- Eric R.D. Moise,
- Deepa S. Pureswaran,
- Evan Shanks, and
- Rob C. Johns
Insect outbreaks can cover vast geographic areas making it onerous to cost-effectively monitor populations to address management or ecological questions. Community science (or citizen science), which entails engaging the public to assist with data collection, provides a possible solution to this challenge for the spruce budworm (Choristoneura fumiferana Clemens), a major defoliating pest in North America. Here, we lay out the Budworm Tracker Program, a contributory community science program developed to help monitor spruce budworm moths throughout eastern Canada. The program outsources free pheromone trap kits to volunteers who periodically check and collect moths from their traps throughout the budworm flight period, then return them in a prepaid envelope to the organizers. Over three years, the program engaged an average of 216–375 volunteers and yielded a data return rate of 68%–89%, for a total of 16 311–54 525 moths per year. Volunteer retention among years was 71%–89%. Data from this program offer compelling evidence for the range of long-distance moth dispersal. Although our program was designed for spruce budworm, this template could easily be adapted for forestry, urban forestry, and agricultural systems to monitor any of the numerous organisms for which there is an established trapping method. - OPEN ACCESS
- Andrea Bryndum-Buchholz,
- Faelan Prentice,
- Derek P. Tittensor,
- Julia L. Blanchard,
- William W.L. Cheung,
- Villy Christensen,
- Eric D. Galbraith,
- Olivier Maury, and
- Heike K. Lotze
Under climate change, species composition and abundances in high-latitude waters are expected to substantially reconfigure with consequences for trophic relationships and ecosystem services. Outcomes are challenging to project at national scales, despite their importance for management decisions. Using an ensemble of six global marine ecosystem models we analyzed marine ecosystem responses to climate change from 1971 to 2099 in Canada’s Exclusive Economic Zone (EEZ) under four standardized emissions scenarios. By 2099, under business-as-usual emissions (RCP8.5) projected marine animal biomass declined by an average of −7.7% (±29.5%) within the Canadian EEZ, dominated by declines in the Pacific (−24% ± 24.5%) and Atlantic (−25.5% ± 9.5%) areas; these were partially compensated by increases in the Canadian Arctic (+26.2% ± 38.4%). Lower emissions scenarios projected successively smaller biomass changes, highlighting the benefits of stronger mitigation targets. Individual model projections were most consistent in the Atlantic and Pacific, but highly variable in the Arctic due to model uncertainties in polar regions. Different trajectories of future marine biomass changes will require regional-specific responses in conservation and management strategies, such as adaptive planning of marine protected areas and species-specific management plans, to enhance resilience and rebuilding of Canada’s marine ecosystems and commercial fish stocks. - OPEN ACCESS
- Lauren E. Eckert,
- Nick XEMŦOLTW_ Claxton,
- Cameron Owens,
- Anna Johnston,
- Natalie C. Ban,
- Faisal Moola, and
- Chris T. Darimont
Policy-makers ideally pursue well-informed, socially just means to make environmental decisions. Indigenous peoples have used Indigenous knowledge (IK) to inform decisions about environmental management for millennia. In the last 50 years, many western societies have used environmental assessment (EA) processes to deliberate on industrial proposals, informed by scientific information. Recently EA processes have attempted to incorporate IK in some countries and regions, but practitioners and scholars have criticized the ability of EA to meaningfully engage IK. Here we consider these tensions in Canada, a country with economic focus on resource extraction and unresolved government-to-government relationships with Indigenous Nations. In 2019, the Canadian government passed the Impact Assessment Act, reinvigorating dialogue on the relationship between IK and EA. Addressing this opportunity, we examined obstacles between IK and EA via a systematic literature review, and qualitative analyses of publications and the Act itself. Our results and synthesis identify obstacles preventing the Act from meaningfully engaging IK, some of which are surmountable (e.g., failures to engage best practices, financial limitations), whereas others are substantial (e.g., knowledge incompatibilities, effects of colonization). Finally, we offer recommendations for practitioners and scholars towards ameliorating relationships between IK and EA towards improved decision-making and recognition of Indigenous rights. - OPEN ACCESS
- Aimee Huntington,
- Patricia L. Corcoran,
- Liisa Jantunen,
- Clara Thaysen,
- Sarah Bernstein,
- Gary A. Stern, and
- Chelsea M. Rochman
Microplastics are a globally ubiquitous contaminant, invading the most remote regions, including the Arctic. To date, our understanding of the distribution and sources of microplastics in the Arctic is limited but growing. This study aims to advance our understanding of microplastics in the Arctic. Surface water, zooplankton, sediment, and snow samples were collected from Hudson Bay to north Baffin Bay onboard the CCGS Amundsen from July to August 2017. Samples were examined for microplastics, which were chemically identified via Raman spectroscopy for surface water and zooplankton and Fourier transform infrared spectroscopy for sediment. We found that 90% of surface water and zooplankton samples, and 85% of sediment samples, contained microplastics or other anthropogenic particles. Mean anthropogenic particle concentrations, which includes microplastics, were 0.22 ± 0.23 (per litre) for surface water, 3.51 ± 4.00 (per gram) for zooplankton, and 1.94 ± 4.12 (per gram) for sediment. These concentrations were not related to the human populations upstream, suggesting that microplastic contamination in the Arctic is from long-range transport. Overall, this study highlights the presence of microplastics across the eastern Canadian Arctic, in multiple media, and offers evidence of long-range transport via ocean and atmospheric currents. Further research is needed to better understand sources, distribution, and effects to Arctic ecosystems. - OPEN ACCESS
- Rebecca K. Dirkes,
- Nathan C. Winn,
- Thomas J. Jurrissen,
- Dennis B. Lubahn,
- Victoria J. Vieira-Potter,
- Jaume Padilla, and
- Pamela S. Hinton
Estrogen receptor-α knockout (ERKO) in female rodents results in bone loss associated with increased osteocyte sclerostin expression; whether this also occurs in males is unknown. Here, we examined the effects of ERKO on femoral cortical geometry, trabecular microarchitecture, and osteocyte sclerostin expression of the femur and lumbar vertebrae. At 14 months of age, male ERKO and wild-type (WT) littermates (n = 6 per group) were sacrificed, and femora and vertebra were collected. Cortical geometry and trabecular microarchitecture were assessed via micro-computed tomography; osteocyte sclerostin expression was assessed via immunohistochemistry. ANCOVA with body weight was used to compare ERKO and WT for cortical geometry; t-tests were used for all other outcomes. Regardless of skeletal site, ERKO mice had greater trabecular bone volume and trabecular number and decreased trabecular separation compared with WT. In the femoral diaphysis, ERKO had lower total area, cortical area, and cortical thickness compared with WT. The percentage of sclerostin+ osteocytes was increased in ERKO animals in cortical bone but not in cancellous bone of the femur or the lumbar vertebrae. In conclusion, ERKO improved trabecular microarchitecture in aged male mice, but negatively altered femoral cortical geometry associated with a trend towards increased cortical sclerostin expression. - OPEN ACCESSWe report on the results of the first mark–recapture survey of freshwater turtles in an isolated urban wetland complex in one of Canada’s fastest growing municipalities. Although we found turtles in every surveyed wetland, the density and assemblage of turtles in smaller wetlands were significantly different than in larger wetland bodies. We also documented two species of turtles that were thought to be absent from this wetland complex, the Northern Map turtle and Eastern Musk turtle. We noted that a wetland that was bisected by a high-traffic road showed a male-skewed sex ratio in the population of Midland Painted turtles but not in the population of Eastern Snapping turtles. As a whole, the sex ratios inside the wetland complex were not skewed. These results reinforce the conclusions of a previous study of a single wetland within this same complex that had found a correlation between road mortality and a male-skewed sex ratio in Midland painted turtles. We discuss population sources and sinks within the complex and the importance of protecting the overland corridors that support the safe turtle movements within this provincially significant wetland complex.
- OPEN ACCESS
- Amy K. Teffer,
- Jonathan Carr,
- Amy Tabata,
- Angela Schulze,
- Ian Bradbury,
- Denise Deschamps,
- Carole-Anne Gillis,
- Eric B. Brunsdon,
- Gideon Mordecai, and
- Kristina M. Miller
Infectious agents are key components of animal ecology and drivers of host population dynamics. Knowledge of their diversity and transmission in the wild is necessary for the management and conservation of host species like Atlantic salmon (Salmo salar). Although pathogen exchange can occur throughout the salmon life cycle, evidence is lacking to support transmission during population mixing at sea or between farmed and wild salmon due to aquaculture exposure. We tested these hypotheses using a molecular approach that identified infectious agents and transmission potential among sub-adult Atlantic salmon at marine feeding areas and adults in three eastern Canadian rivers with varying aquaculture influence. We used high-throughput qPCR to quantify infection profiles and next generation sequencing to measure genomic variation among viral isolates. We identified 14 agents, including five not yet described as occurring in Eastern Canada. Phylogenetic analysis of piscine orthoreovirus showed homology between isolates from European and North American origin fish at sea, supporting the hypothesis of intercontinental transmission. We found no evidence to support aquaculture influence on wild adult infections, which varied relative to environmental conditions, life stage, and host origin. Our findings identify research opportunities regarding pathogen transmission and biological significance for wild Atlantic salmon populations.