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  • OPEN ACCESS
    Wet–dry cycles influence methylmercury concentrations in water in seasonal prairie wetland ponds
    FACETS • Vol. 8 • pp. 1 - 14
    Methylmercury concentrations [MeHg] in whole water were measured in 28 prairie wetland ponds in central Saskatchewan between 2006 and 2012. Ponds fell into four land use categories (established grass, recent grass, traditional cultivated, and certified organic cultivated) and two water level patterns (“Mainly Wet” ponds stayed wet at least until October and “Mainly Dry” ponds dried up each summer). Despite similar atmospheric Hg deposition, average [MeHg] and proportion of total Hg that was MeHg (%MeHg) were higher in water from ponds surrounded with established grass or organic farming; this trend may be driven by high [MeHg] at one Organic site. A stronger relationship was observed with water level patterns. Average [MeHg] and %MeHg were significantly higher in Mainly Wet ponds compared to Mainly Dry ponds. Higher [MeHg] in Mainly Wet ponds were correlated with much higher dissolved organic carbon (DOC) and sulfate (SO4−2) concentrations and higher specific UV absorbance of DOC. We suggest that prairie wetland ponds may not fit the accepted paradigm that wetlands with high [SO4−2] show inhibition of Hg methylation. Our work suggests controls such as the chemical nature of DOC or redox fluctuations in hydrologically dynamic systems may be important in determining net [MeHg] in these sites.
  • OPEN ACCESS
    Structuring forces of intertidal infaunal communities on the northern coast of British Columbia, Canada: assessing the relative importance of top-down, bottom-up, middle-out, and abiotic variables
    FACETS • Vol. 8 • pp. 1 - 14
    While trophic and habitat-related abiotic variables (predation, competition, tolerance, etc.) are known to influence community structure in many ecosystems, some systems appear to be only minimally influenced by these variables. Sampling multiple tidal flat communities in northern BC, Canada, we investigated the relative importance of top-down and middle-out (mesopredators) variables, competition for resources (bottom up), and abiotic variables in structuring an infaunal community (invertebrates living in sediment). Similar to previous studies on mudflats in the Bay of Fundy (also at a north temperate latitude), we determined that these variables accounted for a minor (0%–9%) proportion of the observed variation in this infaunal community, suggesting that these variables play a small role in structuring this community. Based on the results of our study and in combination with previous experiments on infaunal recovery patterns post disturbance, we posit that the main factors influencing these infaunal communities likely operate at a scale of sites (kilometres) and(or) plot (metres or less) but not transects (10–100 m within site). Candidate forces structuring these intertidal communities that need future examination include regional species pools and the variables that affect these pools, sediment biogeochemistry, and disturbance/recovery history of a site. The similarity of our Pacific coast findings to those from the north temperate Atlantic coast suggests some similarity in the processes structuring these distinct infaunal communities.
  • OPEN ACCESS
    A decision framework for the management of established biological invasions
    FACETS • Vol. 8 • pp. 1 - 10
    In some cases, managing an established invasive species may do more harm to an ecosystem than allowing the invader to persist. Given limited resources available to land managers and the realities of conservation triage, we recognized the need for systematic guidance for management decisions made at the “late end” of the invasion curve. We gathered an interdisciplinary group of experts and practitioners to address the question of “under what circumstances is the active management of an established aquatic invasive species warranted?” Our working group identified three key dimensions to this question: (1) the efficacy of available management options; (2) the net benefits of management actions weighed against the null scenario of no control; and (3) the socio-ecological context that defines management goals, a manager’s ability to achieve said goals, and perceptions of management outcomes. These considerations were used to structure a consensus decision tree that supports a multi-criteria approach to decision-making. Our approach promotes interdisciplinarity and systems thinking and emphasizes the need to consider costs and benefits comprehensively, for example by considering the persistence or reversibility of impacts from both the invasive species and from efforts to suppress or eradicate it.
  • OPEN ACCESS
    What is habitat sensitivity? A quantitative definition relating resistance, resilience, and recoverability to environmental impacts
    FACETS • Vol. 9 • pp. 1 - 9
    Habitat sensitivity is a consideration for decision-making under environmental laws in many jurisdictions. However, habitat sensitivity has been variously defined and there is no consistent approach to its quantification, which limits our understanding of how habitat sensitivity varies among systems and in response to different pressures. We review various definitions offered in the scientific literature and policy documents before suggesting a universal framework for habitat sensitivity as (i) a habitat trait that defines the ecological impacts from a given pressure, (ii) which is composed of three components (habitat resistance, resilience, and recoverability), and (iii) which is quantified by measuring the change and recovery in the state of key habitat attributes in response to pressures. In addition, we provide guidance toward a consistent approach to assessing habitat sensitivity, which includes the use of pressure benchmarks and standardized metrics of change in key habitat attributes to create a common scale for comparison among habitat attributes and pressures. Our framework and recommendations should help to standardize the way in which habitat sensitivity is defined and assessed, and could be integrated into decision-making processes to improve ecosystem management in different jurisdictions.
  • OPEN ACCESS
    One informs the other: Unionid species at risk and benthic macroinvertebrate community monitoring data are complementary
    FACETS • Vol. 8 • pp. 1 - 13
    Benthic macroinvertebrate communities, which include unionid freshwater mussels, enhance the health of river ecosystems. Human impacts have driven declines within freshwater mussel communities and due to their complex life cycles, mussel recovery efforts are complex. In Canada, conservation of imperiled species has focused on biodiversity hotspots such as the Sydenham River in the Laurentian Great Lakes Basin. In practice, species conservation and habitat monitoring are siloed between federal agencies and local conservation authorities, limiting the potential for alignment of conservation policy and practice. Here we bring together federal, local, and our own survey data to explore patterns of co-occurrences between mussel species and other macroinvertebrate taxa to explore the extent to which knowledge of one benthic community informs the other. Mussel communities (species richness, community composition) differed between sites where imperiled mussel species were present and/or absent. Benthic macroinvertebrate metrics (e.g., family richness, percent Ephemeroptera, Plecoptera, and Trichoptera taxa) and specific indicator taxa were correlated with mussel species richness and the presence of imperiled mussel species. We show that benthic macroinvertebrate diversity indicators provided insight into imperiled species occurrences that warrant further investigation. These findings underscore support for coordinated watershed monitoring efforts and could be crucial for more successful freshwater mussel conservation.
  • OPEN ACCESS
    Community-led non-invasive polar bear monitoring in the Eeyou Marine Region of James Bay, Canada: insights on distribution and body condition during the ice-free season
    FACETS • Vol. 8 • pp. 1 - 12
    Wildlife conservation is informed by detailed understanding of species demographics, habitat use, and interactions with environmental drivers. Challenges to collecting this information, particularly in remote places and on widely ranging species, can contribute to data deficiencies that detract from conservation status assessment and the effectiveness of management actions. Polar bears in James Bay face rapidly changing environmental conditions at the southern edge of their global range, but studying their ecology has been limited by community concerns about the methods typically used in polar bear research. Using a community-led and non-invasive approach, we deployed hair snare and camera trap sampling stations across 400 km of the Eeyou Marine Region in eastern James Bay. Stations collected >100 hair samples and thousands of photographs in one eight-week period that allowed for a novel investigation of this population’s distribution and body condition during the ice-free season. Polar bears were in average to above average body condition, and model selection of detections at stations revealed distance to mainland as a significant predictor of polar bear presence. Given its high potential, we suggest community-based monitoring using this method become a standard protocol to expand the scope and local leadership of polar bear research across the North.
  • OPEN ACCESS
    Shorebirds exhibit niche partitioning on multiple dimensions at a small staging site on the Northumberland Strait, New Brunswick, Canada
    FACETS • Vol. 8 • pp. 1 - 12
    Animal populations take advantage of environmental heterogeneity to partition themselves into microhabitat niches. Such partitioning plays an important role in regulating interspecific competition and community structure by allowing multiple species to coexist. Atlantic Canada has many small coastal staging sites that host southbound migrant shorebirds. However, most shorebird studies in the region have been focused on larger sites in the Bay of Fundy, resulting in limited knowledge about staging ecology at these small sites, which often host more diverse shorebird assemblages. We examined niche partitioning by shorebirds on the Northumberland Strait, New Brunswick, Canada, to better understand how small coastal staging sites support diverse shorebird populations. We found evidence of partitioning on three niche dimensions: space, foraging behaviour, and diet. Most species specialized in at least one dimension, with foraging constraints based on bill morphology and habitat access based on species size likely driving segregation. Environmental heterogeneity at sites on the Northumberland Strait created multiple dimensions for segregation and fulfilled the niche requirements of diverse shorebird species during migratory staging. These findings broaden our understanding of staging ecology of multispecies flocks and suggest that conservation of small coastal sites is important for success of migratory shorebirds in Atlantic Canada.
  • OPEN ACCESS
    Dynamic vegetation cover and decline in common eider breeding numbers in Nova Scotia, Canada
    FACETS • Vol. 8 • pp. 1 - 12
    The American common eider (Somateria mollissima dresseri) is a colonially nesting sea duck breeding on islands in the coastal regions of Atlantic Canada. Declines in colony size have been pronounced in some parts of its range, notably in Nova Scotia, and may be attributable to a variety of interconnected factors including changes in habitat conditions. Using surveys collected two decades apart, we compared nesting habitat types, availability, and use by breeding eiders on 16 islands that supported >1600 eider nests in 1992–1993, but 830 nests in 2013. While general patterns of eider nesting habitat use remained consistent (e.g., nesting preferences exhibited for Low Shrubland and Grassland habitats, and avoidance of forest or beach habitats), overall vegetation cover declined, but relative habitat changes were inconsistent across islands. Three of the islands with the greatest change in vegetation had cormorant (Phalacrocorax spp.) colonies in 2013 that were not there in the earlier years. We suggest that changes in vegetation, in some cases facilitated by cormorant colony formation, influenced susceptibility of nesting females to predators, and these interconnected factors may be contributing to local population declines.
  • OPEN ACCESS
    Multiple impacts of invasive species on species at risk: a case study in British Columbia, Canada
    FACETS • Vol. 8 • pp. 1 - 13
    Invasive species are a leading cause of biodiversity loss and species extinctions across ecosystems on a global scale. The historical and ongoing focus on single-species management of invasive species and species at risk contributes to inefficiencies in management strategies that present an obstacle to achieving desired outcomes. A holistic approach that consolidates and maps linkages between the broader collective of invasive species and species at risk in an area provides a more appropriate entry point for issue-based, rather than species-based, management planning. We present a case study of this approach from British Columbia, Canada, which synthesized the identity, mechanisms of impact, mechanisms of spread, and magnitude of impacts across 782 unique pairs of invasive species and federally listed species at risk, based on a literature review of species at risk documentation. The resulting dataset was used to summarize the nature of interactions across species pairs and taxonomic groups to help guide the development of invasive species response strategies that make the best use of limited management resources. As species invasions and extinctions become increasingly interconnected, holistic approaches rooted in cumulative effects assessment and ecosystem-based management can provide a stronger foundation for reducing or mitigating this growing threat.
  • OPEN ACCESS
    Niche partitioning of bobcat and Canada lynx near their distribution contact zone
    FACETS • Vol. 9 • pp. 1 - 11
    Canada lynx (Lynx canadensis) are keystone predators. However, contact with congenerics, like the bobcat (Lynx rufus), could alter lynx trophic ecology and destabilize boreal food webs. We set out to describe the trophic niches of these species in allopatry and sympatry to assess how resources are partitioned among them and project whether the northward expansion of the bobcats’ range will lead to the displacement of lynx. To quantify the trophic niche, we measured stable isotopes of carbon and nitrogen in muscle and liver samples of bobcat and lynx. Our results indicate that both bobcat and lynx consumed snowshoe hare as their primary prey. However, lynx specialized on hare throughout our study, whereas bobcats foraged as generalists in sympatry with lynx and hare-specialists in allopatry. Our results highlight the contrasting ecological strategies of two congeneric felids and underscore the potential relevance of foraging efficiency in shaping the trophic niche of consumers in competitive environments.
  • OPEN ACCESS
    Conducting community-led research using trail cameras to develop baseline wandering domestic cat local abundance estimates
    FACETS • Vol. 9 • pp. 1 - 14
    Assessing cat local abundance provides information on where wandering cat numbers are highest and what habitats or factors are associated with wandering cats. A variety of stakeholders can lead this research and then use the findings to make scientifically informed decisions to guide the physical locations of cat management actions. Here, we document a framework that engages community members, uses minimal equipment (six trail cameras), and provides scientifically derived information for interested parties to inform, direct, or test the effectiveness of cat management practices. Using these methods in Gatineau, Quebec, Canada, we demonstrate how we estimated cat population size and cat local abundances across a variety of co-variates while accounting for non-perfect detection by using 55 trail camera sites and N-mixture models. Urban areas had three-fold higher local wandering cat abundances than parkland areas, and neighbourhoods below the median income had the highest local abundances of wandering cats. We estimated there are between 8905 and 48,419 (mean 21,298) wandering cats in Gatineau, with 18%–73% of those cats being unowned. These findings can be used to identify locations for future cat management. If estimates of cat abundance are repeated, they can assess the effectiveness of management actions.
  • OPEN ACCESS
    Graduate student experiences and perspectives related to conducting thesis research within long-term ecological projects
    FACETS • Vol. 9 • pp. 1 - 12
    Long-term ecological research (LTER) projects are considered valuable training grounds for graduate student researchers, yet student voices are largely absent from discussions of LTER merits in the literature. We aimed to identify benefits and challenges encountered by current and former graduate students in conducting graduate research within LTER projects. To explore graduate student experiences and perspectives, we conducted a survey comprising both closed-ended questions (i.e., multiple choice and Likert scale) and open-ended questions. From the responses, we identified emergent categories related to positive and negative experiences using sentiment analysis. We found agreement with purported benefits in areas including networking and access to established field sites and protocols. However, participants also identified data accessibility, authorship decisions, communication, and interpersonal conflicts as significant sources of challenges. We synthesized survey results with existing literature to provide actionable recommendations for principal investigators in four main areas (data, authorship, communication, and management) through an LTER lens. In addition to providing longitudinal data, LTER projects offer graduate students both physical and methodological infrastructure that can serve as the scaffold for new research questions to be developed. However, the likelihood of success of student research, as well as the success of the students themselves, can be improved when the needs of graduate students are prioritized.
  • OPEN ACCESS
    Social media-based community science for turtle nest monitoring and conservation
    FACETS • Vol. 9 • pp. 1 - 7
    In late 2020, a private volunteer group operating through a Facebook group approached Toronto and Region Conservation Authority (TRCA) with an interest in participating in the Citizen Science Nest Protection and Monitoring Volunteer Program. During the 2021 season, TRCA staff virtually trained volunteers in turtle nest detection, protection, and monitoring due to COVID-19 social constraints, and provided necessary supplies and equipment. In 2021 volunteers and staff detected 181 turtle nests and were able to protect 75 nests with simple predator-exclusion devices, while in 2022, 165 nests were detected, and 155 were protected. The volunteers also collected data, including nesting location, date, and species in addition to the number of successful hatchlings (2021 only). In 2021, the 75 protected nests yielded 81 Midland Painted Turtle and 665 Snapping Turtle hatchlings. Five Midland Painted Turtle’s eggs were also recovered from an injured turtle, and 44 Snapping Turtle eggs were recovered from a partially predated nest, transported to the Ontario Turtle Conservation Centre, incubated, hatched, and overwintered, and then released back into the local wetlands. The partnership with a local community group proved effective, and we would recommend this practice to other conservation organizations interested in turtle nest protection.
  • OPEN ACCESS
    Characterizing contemporary evolutionary change in a recently isolated population of threespine stickleback (Gasterosteus aculeatus L.)
    FACETS • Vol. 9 • pp. 1 - 16
    The parallel evolution of lateral plates and body shape in the threespine stickleback (Gasterosteus aculeatus) is an iconic example of adaptation. We test a case of contemporary evolutionary transition in a recently isolated population of marine G. aculeatus in British Columbia, Canada. We investigate Ectodysplasin (Eda) genotypes, plate counts, neutral genetic divergence, and whole-body phenotypes to determine the genetic and phenotypic distance between this population and nearby comparative populations. Our focal population is in the process of adapting both genetically and phenotypically to a freshwater environment, and we provide an example of the genetic basis for parallel evolution on a contemporary timescale. The frequency of Eda genotypes and lateral plate phenotypes in our focal population is not consistent with those of marine or fully freshwater populations. Although our focal population is genetically distinct from nearby marine populations, these fish still more closely resemble marine populations in overall body shape while demonstrating an intriguing intermediate phenotype. Eda frequency and lateral plate phenotype change faster than body shape in response to freshwater conditions, suggesting that the pace of adaptation differs across traits in response to the same environmental conditions. Our results further bolster the case for G. aculeatus as a key model of contemporary evolution.
  • OPEN ACCESS
    Management practices benefit endangered Poweshiek skipperling (Oarisma poweshiek) in Manitoba tall grass prairie
    FACETS • Vol. 9 • pp. 1 - 12
    Poweshiek skipperling (Oarisma poweshiek Parker, 1870) populations have declined precipitously in the past few decades, and their global range is now restricted to two isolated regions, one of which is the managed Manitoba tall grass prairie in Canada. In this paper, we used a decade of survey data from 2010 to 2019 to understand how habitat features, management practices, and extreme weather impact Poweshiek skipperling abundance in Manitoba. The strongest predictor of abundance was the density of black-eyed Susans (Rudbeckia hirta L.), a primary nectar plant for adults. Poweshiek skipperling abundance also had a negative relationship with both the number of years since a burn occurred and the number of years since grazing occurred. Cumulative precipitation during their active period (May–June) had a negative relationship with skipperling abundance, whereas warm early springs and cool temperatures during the active period had positive relationships. These results suggest that management actions that maintain tall grass prairie habitat in an early successional stage (burning and grazing) and maintain important nectar sources benefit this population. In contrast, extreme weather events had varying effects on Poweshiek skipperling abundance. Results from this study inform ongoing management practices in the Manitoba tall grass prairie to support this endangered population.
  • OPEN ACCESS
    Spatial and seasonal determinants of arthropod community composition across an agro-ecosystem landscape
    FACETS • Vol. 9 • pp. 1 - 15
    We used Malaise traps to sample arthropod community composition at biweekly intervals across an agroecosystem landscape in southern Ontario, Canada, to evaluate the relative impact of site spacing, seasonal timing, weather conditions, local plant community attributes, and agricultural extent across the local landscape on spatial and temporal variation in arthropod community composition. The 15 field sites sampled spanned a wide gradient of agricultural extent that in isolation had a strong impact on spatial variation in arthropod community composition. DNA metabarcoding of the samples identified >10 000 different arthropod biodiversity index numbers. Local variation in plant community composition and canopy cover best explained variation in arthropod community dissimilarity. Weather variables followed closely in explanatory power, driven primarily by seasonal variation in temperature. Significant effects of time remained after accounting for environmental variables, with little independent effect of spatial distance. The proportion of agricultural land at the landscape scale had little detectable effect after controlling for the influence of the other environmental variables. Our results suggest that plant community composition, cover, weather conditions, and seasonality structured the arthropod community to considerable degree.
  • OPEN ACCESS
    A comparison of approaches to quantify carbon for ecosystem service assessments through time
    FACETS • Vol. 9 • pp. 1 - 13
    Monitoring of global climate regulation ecosystem services is needed to inform national accounts, meet emission targets, and evaluate nature-based climate solutions. As carbon monitoring is context-dependent, the most useful methodological approach will depend on the spatial extent and resolution, temporal frequency, baseline, available data, funding, and dominant drivers of change, all of which will impact results and interpretation. Here, focusing on above and belowground carbon storage and sequestration, we review four groups of methods for estimating trends in carbon over time: (1) field-based measurements, (2) land cover maps with reference carbon values by land cover type, (3) statistical and machine learning models linking field measurements to remotely sensed data, and (4) mass balance models representing key carbon pools and flows between them. We discuss strengths, limitations, and best practices for each method to assist researchers in implementing an approach or critically evaluating whether an existing carbon dataset can be used for a different project. The best methods often account for spatial variability of carbon, ecosystem interconnections, and temporal stability of carbon stocks against future environmental changes. Effective carbon monitoring can help determine optimal conservation, restoration, and/or land management interventions with win-win outcomes for both conservation and nature-based climate solutions.
  • OPEN ACCESS
    Survey of rice (Oryza sativa L.) production ecosystems in northern Ghana confirms low risk of exposure to potential toxic elements from local grain consumption
    FACETS • Vol. 9 • pp. 1 - 7
    Expanding local rice production to meet consumer demand is a priority action under the Government of Ghana’s Planting for Food and Jobs initiative. While studies on yield-enhancing interventions abound, fewer studies focus on food safety issues (e.g., the potential toxic element status of the production ecosystems). This study was, therefore, conducted to bridge the knowledge gap. Chemical analyses were conducted on water, soil, and rice grain samples from different production ecosystems in the Northern and Upper East regions of Ghana. Statistical analysis of the data showed that soil and rice grain arsenic concentrations were significantly higher (P < 0.001) in the Upper East region. In the Northern region, mean cadmium concentration in rice grains from the irrigated lowland fields (0.023±0.003 mg/kg) was significantly higher than in grains from the rainfed fields. All recorded concentrations of rice grain arsenic, cadmium, and lead were, however, within permissible limits, indicating a low risk of dietary exposure. The observed differences in concentrations within and between regions suggest that soil texture and other geogenic factors could influence the potential toxic element status of the rice production ecosystems. Regular monitoring is, therefore, recommended to maintain the safety of Ghana’s locally produced rice for human consumption.
  • OPEN ACCESS
    A toolkit for greater equity, diversity, and inclusion in early-career ecology funding
    FACETS • Vol. 9 • pp. 1 - 9
    Funding is critical in ecology and related fields, as it enables research and sustains livelihoods. However, early-career researchers (ECRs) from diverse backgrounds are disproportionately underrepresented as funding recipients. To help funding programs self-evaluate progress towards increasing equity, diversity, and inclusion (EDI) in their funding opportunities, we introduce the Stage-based Assessments of Grants for EDI (SAGE) Toolkit. Developed using existing literature, semi-structured interviews, and coauthors’ experiences, the toolkit considers how each funding stage (Advertisement, Application, Review, Awarding) interacts with applicants from racialized and other underrepresented backgrounds. The toolkit offers specific criteria and recommendations, with explanations and examples from funding agencies, to support applicants who have been historically marginalized in ecology and are often left out of equitable funding consideration. Changes in funding mechanisms alone will not reverse the marginalization of communities and peoples in the field of ecology, but advancing EDI must include action throughout the grant process. Efforts to increase EDI must be sustained, and the toolkit allows for additional considerations and evolving best practices. With the SAGE Toolkit, efforts to increase EDI can help to transition away from a transactional dynamic between funder and applicant to instead supportive community and collaboration. The SAGE Toolkit is available online at bit.ly/ediSAGEtoolkit.
  • OPEN ACCESS
    Now is the time for academics to think and act beyond academia
    FACETS • Vol. 9 • pp. 1 - 3
    Despite the challenges posed by climate change and the biodiversity crisis, most academic research continues to stay within academia and the gaps between conservation science, policy, and practice remain intact. We need to improve the exchange of evidence between researchers and conservation practitioners and focus on solutions-oriented, interdisciplinary science and co-developed research. As we continue to break climate records and lose record numbers of species every year, now is the time for academics to think and act beyond their institutions.