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  • OPEN ACCESS
    Julie Morand-Ferron retrospective (1977–2022) for FACETS
    FACETS • Vol. 9 • pp. 1 - 4
  • 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 riffle restoration on the recovery of endangered Nooksack Dace (Rhinichthys cataractae sp. cataractae)
    FACETS • Vol. 9 • pp. 1 - 15
    The Nooksack Dace (Rhinichthys cataractae sp. cataractae) is a federally endangered riffle specialist endemic to the lower Fraser Valley of British Columbia, Canada, with historic population declines associated with riffle loss from stream dredging, channelization, and excessive sediment inputs. To assess the effectiveness of riffle restoration as a recovery strategy, gravel and cobble riffles were constructed in two replicate tributaries of the Nooksack River as a before-after-control-impact experiment, measuring dace abundance, substrate composition, and invertebrate biomass before and one year after restoration. Nooksack Dace density increased significantly in cobble (but not gravel) treatments relative to control riffles. Dace abundance was strongly associated with increased availability of interstitial refuges rather than substrate effects on invertebrate prey abundance, suggesting that interstitial space limits adult dace abundance. Young-of-the-year dace were not observed in one of the two restored streams despite riffle restoration, indicating increased dace density due to aggregation in higher-quality restored riffles. This recruitment limitation indicates persistence of a population bottleneck at an early life history stage that is not addressed by successful restoration of adult riffle habitat.
  • OPEN ACCESS
    Seasonal movement and habitat use of Bull Trout (Salvelinus confluentus) near the northern geographic range extent
    FACETS • Vol. 9 • pp. 1 - 15
    The movement ecology of Bull Trout (Salvelinus confluentus) in watersheds at the northern geographic range extent is not well understood. We implanted 54 Bull Trout with acoustic transmitters in the Prairie Creek watershed, Northwest Territories, Canada and tracked fish from July 2011 to October 2012 using 19 stationary hydrophones. Bull Trout movement patterns generally corresponded to two groups, as a result of individual variation within and across seasons. The first group exhibited seasonal variations in movement and habitat use, moving most (range 11.7–115.9 km) and occupying the largest home ranges in summer and autumn, while exhibiting little movement during winter and spring. The second group made negligible movements within seasons and resided in localized areas. Restricted movement in winter resulted in a severe range contraction. The average distance moved within a season was 11.5 km (range 0.3–64.9 km per fish). The unusually high prevalence of stationarity in this watershed suggest fish can complete all life processes (spawning, feeding, and rearing) in short reaches (<10 km) of Prairie Creek and tributaries. We encourage researchers to replicate our work in other northern watersheds to determine if the life history we describe represents a regional divergence from more southerly populations.
  • OPEN ACCESS
    Effects of acute suspended sediment exposure on the swimming and schooling performance of imperilled Redside Dace (Clinostomus elongatus)
    FACETS • Vol. 9 • pp. 1 - 10
    Urbanization is a widespread threat to freshwater ecosystems. After rainfall, urban streams often experience unnaturally fast water flows and acute increases in suspended sediment due to the high degree of adjacent impervious land surface. Suspended sediments may negatively affect fishes by impairing respiration, and reduced water clarity may also affect social behaviours such as schooling that are dependent on visual cues. Given these two mechanisms of harm, suspended sediments may therefore exacerbate the difficulty of swimming at high water velocities. We tested this idea using imperilled Redside Dace (Clinostomus elongatus) to examine the consequences of suspended sediment on swimming performance and schooling behaviour. Using individual fish, we assayed swimming performance (standard critical swim speed test) and tail beat frequency and amplitude under a range of ecologically relevant sediment concentrations. Next, we measured the impact of sediment on the cohesion and polarization of schools. Swimming performance of individual fish was not affected by suspended sediment levels we examined. School polarization was positively correlated with water flow overall and at the fastest flows we tested; schools were more polarized when exposed to sediment. School cohesion decreased with increasing flows and was unaffected by the suspended sediment levels we examined. Our results collectively suggest that swimming performance of Redside Dace may be resilient to ecologically relevant acute suspended sediment exposure.
  • OPEN ACCESS
    Bull kelp (Nereocystis luetkeana) growth rates as climate stress indicators for Canada’s Pacific coast
    FACETS • Vol. 9 • pp. 1 - 19
    Primary producers’ growth rates are ideal bioindicators of changing climate due to their sensitivity to environmental conditions. On the Central Coast of British Columbia, we assessed growth rates of Nereocystis luetkeana, a canopy-forming annual kelp, by assessing baseline variability in growth rates and their response to environmental conditions of over 600 individuals and across three sites (2016–2019). Optimal growth rates for blades and stipes (∼13–14 cm/day) occurred within a narrow range of local environmental conditions. Growth decreased at temperatures > 10 °C, below 1 µm/L nitrate concentration, and surface light availability reduced blade growth at low and high levels (daily light integral or DLI <20 and >40 mol/m2/day). Spatiotemporal variability in these environmental drivers co-occurred with differences in growth rates, suggesting that local conditions strongly influenced growth. In particular, temperature and nutrients were un-coupled seasonally in this region, with more variable responses in growth over the primary growing season (May to September). Overall, the sensitivity of the growth rates of this annual kelp to changing climatic conditions suggests that it is a useful bioindicator for management and marine planning efforts (e.g., restoration and aquaculture) across its species range and provides a feasible metric for monitoring.
  • OPEN ACCESS
    Bigmouth Buffalo (Ictiobus cyprinellus) migratory behaviour and seasonal home range overlap are functions of geographic space in a fragmented riverscape
    FACETS • Vol. 9 • pp. 1 - 17
    In temperate rivers, where environmental conditions vary seasonally, many fishes migrate among summer, spawning, and winter habitats. Dams disrupt these migrations, limiting access to habitat and potentially affecting populations. Bigmouth Buffalo (Ictiobus cyprinellus) is a species of fish with at-risk populations in central Canada. The impact of dams on the extent of Bigmouth Buffalo migration and the overlap between summer and winter home ranges is unknown. Here, we assessed the migratory history of 80 Bigmouth Buffalo tagged with acoustic transmitters in the Red River (USA and Canada), a large binational waterway regulated by semi-passable dams. We sought to understand when and why Bigmouth Buffalo migrate, and how river use varies seasonally. Following more than 6 years of data collection, we found that the degree and probability of overlap between winter and summer home ranges varied by river section between barriers. Importantly, overlap was lowest in the longest continuous river section where well-defined migratory behaviours were observed. The results of this study reveal previously unknown details about Bigmouth Buffalo migration, demonstrate the consequences of river fragmentation on geographic space use, and highlight the importance of river connectivity to fish migration.
  • 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
    Marine ecozones represent a major gap in Canadian DNA barcoding efforts
    FACETS • Vol. 9 • pp. 1 - 11
    Because of Canada’s large size, it is impractical to obtain a comprehensive perspective on biotic change through morphological approaches. DNA metabarcoding offers a potential path, but its application requires access to a well-parameterized DNA barcode reference library. This study presents the current state of DNA barcode coverage for Canadian animals, highlighting progress, identifying gaps, and providing recommendations for future research. Our analysis indicates that many of the known species (100 000 terrestrial and 6000 marine) in the Canadian fauna possess DNA barcode coverage, but there are important gaps geographically and taxonomically. We summarize DNA barcode coverage for the species in freshwater, marine, and terrestrial environments by ecoregion, finding that 95.6% of the 2.3 million Canadian barcode records derive from terrestrial ecosystems. Although the density of barcode records per 100 km² is 13x higher for terrestrial than aquatic environments (22.4 vs. 1.7), coverage for 58% of marine species is available (54% for annelids, 52% for arthropods, 88% for chordates, 39% for echinoderms, and 46% for molluscs). By revealing data-deficient areas and taxonomic groups, this study offers a roadmap for expanding the DNA barcode library for the Canadian fauna as an essential foundation for the scalable biosurveillance initiatives that inform biodiversity conservation efforts.
  • OPEN ACCESS
    The changing agricultural landscape in Canada’s Mixedwood Plains Ecozone (2011–2022) and the implications for biodiversity
    FACETS • Vol. 9 • pp. 1 - 11
    The prairies and savannahs historically found in the Mixedwood Plains Ecozone have been largely converted into farmland, the dominant present-day land cover. Consequently, many species native to these grasslands have shifted to inhabiting suitable agricultural lands. More recently, agricultural intensification has led to the conversion of pastures and hay fields to annual crops, further removing habitat suitable for the persistence of grassland species. We quantified the shift from pasture and forage to annual crops as well as the dynamics among agricultural lands and other land covers in the Mixedwood Plains Ecozone, predicting biodiversity implications by providing a case study on Eastern Meadowlark (Sturnella magna (Linnaeus, 1758)). The total agricultural land area changed little over the study period, but area of pasture and forage decreased while row crop area increased. The loss of agricultural lands to urbanization was partly offset by the conversion of forests and wetlands; however, the farmland gained was of lesser agricultural quality than the farmland lost. Declines in Eastern Meadowlark abundance correlated significantly with carrying capacity loss, suggesting that habitat availability is a limiting factor for this species. We highlight the importance of land management policies to minimize the impacts of land conversion on biodiversity and agricultural production.
  • OPEN ACCESS
    Weaving ways of knowing in practice: a collaborative approach to prioritizing community knowledge and values in wildlife camera monitoring with Magnetawan First Nation
    FACETS • Vol. 9 • pp. 1 - 17
    There is not one singular way to weave together Indigenous and Western knowledges; creating meaningful cross-cultural collaborations requires a foundation of relationships rooted in the context of specific people and place. As interest in working across knowledge systems increases, our goal is to provide an example of respectful and appropriate cross-cultural collaboration within environmental practice. We demonstrate our collaborative, mixed-methods approach to developing a community-based wildlife monitoring program with Magnetawan First Nation that prioritizes community knowledge and values. Through community interviews and a youth sharing circle, participants highlighted values (respect, interconnection, reciprocity, collaboration, and relationship) as well as research priorities, providing examples of what each may look like in practice, to inform our monitoring approach. These examples, paired with reflections from the research team, are shared to explore the process of weaving together knowledge and values to co-create a community-based wildlife monitoring program, applying wildlife cameras as much more than simply a tool for data collection. This research provides tangible examples of weaving together knowledges and values in the context of environmental monitoring, helping guide future cross-cultural collaboration to ensure this work is being done in a good way.
  • 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
    Multifacets in silico study of Plant Defensin 1.1 protein (PDF1.1) in Brassica rapa (turnip)
    FACETS • Vol. 10 • pp. 1 - 16
    Brassica rapa (turnip) belongs to the Brassicaceae family. Due to the diseases caused by fungal pathogens such as Erysiphe cruciferarum, Alternaria japonica, and Alternaria brassicae, the yield of B. rapa was reduced in many Asian and European countries. Plant defensins (PDFs) are proteins that have antifungal properties. This research aimed to comprehend the key attributes of B. rapa PDF 1.1s by incorporating a wide range of in silico approaches. Initially, we explored orthologues of PDF 1.1 in B. rapa through Blastp in Phytozome v.13 which highlighted fourteen different orthologues. Afterward, by using Mega X, the homology of B. rapa PDF1.1 proteins with Arabidopsis thaliana PDF1.1 proteins was also inferred. While, the results of NCBI CD show that these proteins possessed a common domain, i.e., gamma-thionin. The major findings of this study included the crucial characteristics of PDF1.1 proteins that were explored by utilizing the PANZZER2 web server and BlastKOALA, which proposed that these proteins possessed degradation ability of pathogen’s cells and were also found to be involved in a mitogen-activated protein kinase signaling pathway. Overall, this research provided a better understanding of the crucial contribution of B. rapa PDFs 1.1 under biotic stress specifically, the pathogenic fungal attack.
  • 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
    American lobster (Homarus americanus) hepatopancreas transcriptome reveals the significance of chitin-related genes during impoundment shell disease
    FACETS • Vol. 9 • pp. 1 - 10
    American lobsters (Homarus americanus) stored in open tidal pounds can develop impoundment shell disease (ISD), resulting in decreased marketability of the lobsters on the live market. Little is known about ISD or the immunological responses of lobsters exhibiting this disease. The objective of this project was to identify genes from H. americanus hepatopancreas that are differentially expressed in response to ISD. Lobsters were separated into asymptomatic, moderately symptomatic, and severely symptomatic groups, which represent animals with 0%, 5%–20%, and >20% lesion coverage of the carapace, respectively. RNA-seq analysis found that 134 genes were differentially expressed between groups (false discovery rate (FDR) < 0.05). Most, 80, of these genes were found exclusively in the comparison between moderately symptomatic and asymptomatic groups. All animals clustered in their proposed groups based on the expression of the differently expressed genes (DEGs), and the asymptomatic group clustered as an out-group. The expression of most DEGs was higher in the asymptomatic group than the others, which could be related to a stronger response against the disease or differences in individual resistance against ISD development. Among these genes, we highlight eight chitin-related genes, one α-2-macroglobulin-like gene, one acute phase serum amyloid A gene, one pseudohaemocyanin gene, and one trypsin-1-like gene.
  • OPEN ACCESS
    Bat handlers, bat bites, and rabies: vaccination and serological testing of humans at risk
    FACETS • Vol. 9 • pp. 1 - 11
    Globally, bats provide critical ecosystem services. Rabies, caused by rabies virus and related lyssaviruses, is one of the most significant zoonoses associated with bats. Bat biologists study bats in the laboratory and the field. To minimize the risk of disease, all bat handlers should be vaccinated against rabies and undergo routine serological testing to measure their rabies virus neutralizing antibody levels. They should use best practices to avoid exposures, such as personal protective equipment, especially gloves appropriate to the size of the bat(s) being handled. Attention to such details will prevent unnecessary exposures and avoid some of the accompanying negative perceptions that endanger bats on a global level. The small body sizes of many bats (<50 g, many <20 g) and small teeth makes their defensive bites easy to overlook. Breaks in the skin, however small, may result in exposure to lyssaviruses in the animals’ saliva. Exposure to blood-feeding bats is less common because these species are geographically restricted to the Neotropics and are the only species whose natural feeding behavior could involve transmission of rabies virus. Understanding viral transmission, preventing exposures, and responding appropriately to bites will minimize the consequences of this deadly zoonosis.
  • 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”.