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  • OPEN ACCESS
    Winter diet of five sympatric ungulates in west-central Alberta, Canada—inference from DNA metabarcoding of fecal pellets
    FACETS • Vol. 10 • pp. 1 - 13
    Diet is one of the determinants of ungulate ecology. However, there have been few studies of the diet of sympatric ungulates in western Canada. We used DNA metabarcoding of fecal samples to evaluate the winter diet of white-tailed deer (Odocoileus virginianus), mule deer (O. hemionus), moose (Alces americanus), elk (Cervus canadensis), and caribou (Rangifer tarandus caribou) in west-central Alberta. We found that forbs comprised 53%–82% of the reads from plant DNA, while mosses, sedges, grasses, and shrubs made up relatively little of each ungulate’s diet. There was considerable overlap in the winter diet of the five ungulates (Horn-Morisita index = 42%–64% overlap; Bray-Curtis index = 20%–45% overlap). Moose had the most distinct diet, while elk and caribou had the least distinct. However, our analysis was restricted to a coarse taxonomic resolution (family). Lichen species were not identifiable, beyond their fungal component and a number of taxonomic assignments were difficult to rationalise given our knowledge of the diet of the five ungulate species and the ecology of west-central Alberta, Canada. DNA metabarcoding of fecal samples is efficient, but apparent limitations with the technique restrict the description and quantification of diet of the five species of ungulate that we studied.
  • OPEN ACCESS
    The effect of nutrient transport downstream on food web stability in an experimental freshwater meta-ecosystem
    FACETS • Vol. 10 • pp. 1 - 15
    Recent spatial nutrient transport theory suggests that accumulation of nutrients downstream in riverine systems can amplify the magnitude of phytoplankton and zooplankton blooms and/or lead to competitive replacement of phytoplankton by less edible species, such as cyanobacteria. We used an experimentally controlled three-node network of freshwater mesocosms with green algae, cyanobacteria, and Daphnia magna to test these hypotheses. Nutrients and detritus accumulated significantly downstream, reaching maximum values in the terminal nodes, resulting in small increases in abundance for green algae and D. magna populations. Stability analysis from the Lotka–Volterra competition model for green algae and cyanobacteria did not provide evidence of complete competitive exclusion, but cyanobacteria projected to equilibrate at densities 50% higher than those of green algae in all nodes. Our results support the theoretical prediction that unidirectional flow in riverine systems contributes to accumulation of nutrients downstream and increased heterotrophic bacterial activity, but these changes were of insufficient magnitude to produce variance- or mean-driven destabilization of food web relationships downstream in our experimental system.
  • OPEN ACCESS
    No evidence of migration in a 4-year study of an at-risk migratory fish—the centenarian bigmouth buffalo (Ictiobus cyprinellus) of Saskatchewan
    FACETS • Vol. 10 • pp. 1 - 10
    The bigmouth buffalo (Ictiobus cyprinellus, Valenciennes 1844) is a long-lived freshwater fish native to North America that is listed as a species of special concern in its Saskatchewan-Nelson range. Little is known about their ecology and behavior, especially in the Saskatchewan Qu'Appelle River system where it faces multiple threats such as habitat fragmentation and competition with invasive species. In this study, we used acoustic telemetry to track the movements of 44 bigmouth buffalo throughout the Qu'Appelle River system in 2017–2019, and 2021, to monitor migration patterns from spring to fall and investigate if any of the five dams were impeding their ability to access either breeding or overwintering grounds. We found that bigmouth buffalo demonstrated minimal use of the river during this 4-year study, instead staying within the confines of a single lake year-round. Our results suggest that bigmouth buffalo in the Qu'Appelle River do not exhibit migratory behavior during nonflooding years. Considering their extended lifespan (>125 years), this could be attributed to their potential bet-hedging strategy for spawning primarily during flood years. The results indicate that bigmouth buffalo voluntarily remained within Buffalo Pound Lake throughout the study period. Whether this behavior was natural or was influenced by modifications to the system’s hydrology requires further investigation.
  • OPEN ACCESS
    The many pathways of climate change affecting coastal ecosystems: a case study of western Vancouver Island, Canada
    FACETS • Vol. 10 • pp. 1 - 18
    Climate change threatens marine ecosystems with known effects on marine life, including changes in metabolic rates, survival, and community structure. Based on a structured literature review, we developed a conceptual “pathways of effects” model that summarizes how three stressors associated with climate change (warming, acidification, and storms) affect functional species groups on the West Coast of Vancouver Island, Canada. We identified 155 distinct pathways from the three stressors through 12 categories of biological effects ranging from changes in the biochemistry of individual organisms to effects on community composition. Most species groups were affected by several climate stressors and via many pathways, although individual studies generally considered only a small fraction of relevant pathways. These effects depended on the species of interest and geographical location, highlighting the importance of local research. Climate change stressors exert complex, sometimes contradictory effects that vary across ecological scales. For example, some stressors that adversely affected a species in laboratory studies appeared beneficial in community-scale field studies. Pathways of effects models are helpful tools to summarize scientific studies across ecological scales. Compiling them in standardized databases would allow researchers and practitioners to search across species and regions to better support ecosystem-based management and environmental impact assessment.
  • OPEN ACCESS
    Does selenium offset methylmercury toxicity across trophic levels in a primary producer, Auxenochlorella pyrenoidosa, and a detritovore, Aeolosoma variegatum?
    FACETS • Vol. 10 • pp. 1 - 13
    Methylmercury ([CH3Hg]+ or MeHg) is a potent neurotoxin that impairs functioning of the nervous system, and selenium (Se) is known to provide a protective effect against MeHg. Experiments were run to investigate the expected offsetting of MeHg toxicity by Se across trophic levels at the base of the aquatic food chain. An algal primary producer, Auxenochlorella pyrenoidosa, was exposed to MeHg (2 µg L−1) in the presence or absence of varying levels of Se (0 µg L−1, 2 µg L−1, and 5 µg L−1). Results showed that MeHg decreased the maximum density of Auxenochlorella, which Se did not offset. Equal amounts (8 mg) of the algal biomass produced under exposure conditions were subsequently fed to a detritovore, Aeolosoma variegatum (a small freshwater annelid worm). When consuming dietary Se in MeHg contaminated water, or when consuming dietary Se with dietary MeHg, Aeolosoma populations experienced a rescue effect against MeHg, i.e., they achieved greater final population density. Understanding safe levels of dietary Se that provide population level protection against MeHg is a critical step towards managing mercury in contaminated ecosystems.
  • OPEN ACCESS
    Evaluation of a decade of management of a North American aquatic invasive species (Nitellopsis obtusa) highlights scale-dependent effectiveness and monitoring gaps
    FACETS • Vol. 10 • pp. 1 - 14
    Nitellopsis obtusa (starry stonewort) is an invasive macroalga subject to substantial control efforts in the Midwestern United States; however, there has not been systematic evaluation of treatment effectiveness. We synthesized management approaches and outcomes using monitoring performed over a decade-long period across 38 lakes in Indiana, Wisconsin, and Minnesota. Copper-based algaecide treatments were the primary means of control, followed by physical removal methods or combination treatments. Control efforts and associated monitoring data varied by spatial scale, as did surveyors’ N. obtusa sampling methods. At the largest (whole-lake) scale, we found no evidence that algaecide treatments were slowing expansion or reducing abundance of N. obtusa within infested lakes. At smaller, within-lake scales, we found that algaecide and physical treatments could reduce N. obtusa frequency and biomass, but outcomes were highly variable. At the smallest scales, hand pulling was an effective containment strategy for small, localized populations that were detected early. These results highlight the need to set realistic goals for N. obtusa control and develop improved management techniques. There were also critical gaps in monitoring that limited our ability to evaluate treatment effectiveness. In particular, increased monitoring of unmanaged reference lakes and untreated areas within managed lakes is needed.
  • OPEN ACCESS
    Investigating the potential uptake of microplastic-derived carbon into a boreal lake food web using carbon-13 labelled plastic
    FACETS • Vol. 10 • pp. 1 - 9
    Microplastics degrade slowly over time, leaching carbon (C) that could be subsequently incorporated into aquatic food webs. Current estimates of microplastic degradation vary, and little is known about microplastic-derived C fate under natural environmental conditions. To investigate whether microplastics leach C that is subsequently incorporated into aquatic food webs, we added isotopically enriched microplastics to Lake 378 at the Experimental Lakes Area in Ontario, Canada. In an ∼1100 L limnocorral (in situ open-bottom enclosure), we added 99% 13C-labelled polystyrene (8–216 µm in longest dimension) at a nominal concentration of 3268 particles/L. A second limnocorral without microplastics served as a negative control. Monthly measurements of δ13C-DIC and δ13C-DOC in filtered water revealed no detectable leaching of 13C from the plastic. Compound-specific isotope analysis of δ13C in amino acids of bulk plankton and periphyton revealed a slight (0.5‰) enrichment in 13C, within the range of natural variability for these organisms. Under the natural conditions of temperate oligotrophic lakes, degradation of microplastics is likely a very slow process that was not possible to detect in this 4-month experiment. Future studies should focus on assessing degradation of microplastics under realistic field scenarios to improve estimates of degradation pathways and associated time scales.
  • OPEN ACCESS
    Data and knowledge needs for improving science and policy for peatlands in Canada in a changing world: insights from Global Peatlands Initiative Workshop, June 2023
    FACETS • Vol. 10 • pp. 1 - 19
    Knowledge and data on the current function, future threats, and benefits of peatlands in Canada are required to support evidence-based decision-making to ensure they continue to provide critical ecosystem services. This is particularly relevant for Canada, given the large expanse of relatively intact peatland area. There is a need, not only to standardize protocols, but also to prioritize types of information and knowledge that can best meet conservation and management goals. This was the challenge posed to the participants of the Global Peatlands Initiative workshop in June 2023 in Quebec City, Quebec, Canada. Participants were composed of researchers using primarily Western science approaches that use peatland data for carbon accounting, policy or sustainable land use, reclamation/restoration, conservation, wildlife, and water resources applications. For seven peatland data categories (hydrometeorological and environmental sensing; peat coring and depth; greenhouse gas monitoring; biodiversity; vegetation, woody debris, and litter; Traditional Knowledge; water quality), three priority measurements were identified and recommendations for their collection were discussed. The key recommendations from the workshop were to (1) create standardized, yet flexible protocols; (2) coordinate field data collection where possible; (3) weave more Traditional Knowledge into understanding of peatlands; (4) create an atlas of existing peatland information; (5) scope opportunities to create a network of peatland “super sites”.
  • OPEN ACCESS
    Anthropogenic impacts on seagrass habitat connectivity: a model to explore potential links between human activity and marine invertebrate metapopulation persistence
    FACETS • Vol. 10 • pp. 1 - 15
    Coastal ecosystems face numerous stressors from anthropogenic activities. Furthermore, local stressors that directly impact ecological processes in one location can scale up to have indirect regional consequences. In the case of dispersing marine invertebrates, human activity may impact dispersal and survival rates, which can then alter connectivity patterns and metapopulation dynamics across the seascape. Here, we developed a framework to model metapopulation persistence of seagrass-associated invertebrates in the Salish Sea, focusing primarily on British Columbia, Canada. We combined a biophysical model of dispersal with metrics of habitat naturalness to model how local human activities that may impact dispersal can alter habitat connectivity patterns and potentially impact regional metapopulation persistence. We found that human activities that potentially impact dispersal can reduce population persistence across a region, although the effect varied based on location, population dynamics, and severity of the impacts modeled. The majority of populations, however, remained persistent, suggesting that there are robust and redundant pathways of dispersal that can maintain population connectivity in the face of local disturbances. This study highlights the importance of understanding human impacts and connectivity together in a regional context which could have implications for future marine spatial planning and the effective management of biodiversity.
  • OPEN ACCESS
    Correction: Spatial and seasonal determinants of arthropod community composition across an agro-ecosystem landscape
    FACETS • Vol. 10 • pp. 1 - 7
  • 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
    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.