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  • OPEN ACCESS
    Heliocaminiform structures: plant organs that function as microgreenhouses
    FACETS • Vol. 9 • pp. 1 - 20
    Plant structures that enclose trapped air are morphologically and taxonomically diverse. They range from pubescence (trichomes) on various parts of plants to flowers, inflorescences, stems, culms (above-ground jointed stems of grasses), petioles, peduncles, scapes, fruits, bracts, leaves, galls, algal pneumatocysts, moss sporophytes, lichen podetia, and fungal fruiting bodies. Despite being familiar, such structures have not been studied systematically until recently when their complex thermodynamic functionality as microgreenhouses has been recognized. We propose the term “heliocaminiform” (Greco-Latin origin for “sun-room”) provides an umbrella term that describes form and function. Almost all the hollow structures we have examined have elevated internal temperatures of several degrees C above the surrounding air in sunshine, but those are abolished under cloud or at night. The potential importance for the additional heat is presumed to be in growth, maturation, reproduction, sexual function, and overall fitness of the plants. There seem to be no experimental studies on those effects even though they may help explain aspects of plants’ responses to climate change and to phenological mismatches with symbionts (mutualists and herbivores) as ecologically co-dependent partners. Our review and observations opens a remarkably new and hitherto surprisingly neglected avenue in botany which we hope others will explore.
  • OPEN ACCESS
    Integrative adaptive management to address interactions between biological invasions and protected area connectivity: a Canadian perspective
    FACETS • Vol. 8 • pp. 1 - 12
    Expanding and creating protected area networks has become a central pillar of global conservation planning. In the management and design of protected area networks, we must consider not only the positive aspects of landscape connectivity but also how that connectivity may facilitate the spread of invasive species, a challenge that has become known as the connectivity conundrum. Here, we review key considerations for landscape connectivity planning for protected area networks, focusing on interactions between network connectivity and the management of invasive species. We propose an integrative adaptive management framework for protected area network planning with five main elements, including monitoring, budgeting considerations, risk assessment, inter-organizational coordination, and local engagement. Protected area planners can address the dynamic aspects of the connectivity conundrum through collaborative and integrative adaptive management planning.
  • OPEN ACCESS
    Ideal free distributions form across a regulatory boundary in the Northwest Atlantic Fisheries Organization (NAFO) Division 4X and 5Z groundfish fisheries
    FACETS • Vol. 9 • pp. 1 - 9
    We used isodars, developed from the ideal free distribution (IFD), to predict the distribution of fishing effort across regulatory boundaries in the south-western Scotian Shelf’s haddock fishery. Our analysis was focused around the boundary between Northwest Atlantic Fisheries Organization’s Divisions 4X and 5Z. While effort within 4X was related to the standardized catch value and effort experienced along the 4X–5Z boundary, most effort predictions across the boundary were also accurate. Accuracy of these cross-boundary isodars suggests that a high degree of movement across the boundary meets the IFD assumption of free movement and thus, effort on one side of the boundary is related to fishing success on the other side of the boundary. Fisheries management strategies should adopt a broad view that encompasses adjacent regulatory regions to understand where vessels may choose to fish when multiple regulatory regions are accessible. In fisheries where isodars describe effort distributions across a regulatory boundary, the relative abundance of the underlying fish population could be better indicated by effort distribution among regulatory regions than by catch rates.
  • OPEN ACCESS
    Evaluating the design of the first marine protected area network in Pacific Canada under a changing climate
    FACETS • Vol. 9 • pp. 1 - 18
    Marine protected area (MPAs) networks can buffer marine ecosystems from the impacts of climate change by allowing species to redistribute as conditions change and by reducing other stressors. There are, however, few examples where climate change has been considered in MPA network design. In this paper, we assess how climate change considerations were integrated into the design of a newly released MPA network in the Northern Shelf Bioregion in British Columbia, Canada, and then evaluate the resulting network against projected physical and biogeochemical changes and biological responses. We found that representation, replication, and size and spacing recommendations integrated into the design phase were met in most cases. Furthermore, despite varying degrees of projected changes in temperature, dissolved oxygen, and aragonite saturation across the MPA network, suitable habitat for demersal fish species is projected to remain in the network despite some redistribution among sites. We also found that mid-depth MPAs are particularly important for persistence, as fish are projected to move deeper to avoid warming in shallower areas. Our results highlight that a representative MPA network with adequate replication, that incorporates areas of varying climate change trajectory, should buffer against the impacts of climate change.
  • OPEN ACCESS
    Estimating size-at-harvest from Indigenous archaeological clamshell assemblages in Coastal British Columbia
    FACETS • Vol. 9 • pp. 1 - 15
    Shellfish have supported Indigenous lifeways on the Pacific Coast of North America for millennia. Despite the ubiquity of clamshells in archaeological sites, shell size measurements are rarely reported due to a lack of applicable basis for generating size estimates from fragmentary remains. We present a linear regression-based method for determining shell length from hinge and umbo measurements of littleneck (Leukoma staminea; n = 239), butter (Saxidomus gigantea; n = 274), and horse (Tresus nuttallii; n = 92) clams using both contemporary and archaeological shells collected from three regions in coastal British Columbia, Canada. We examine the accuracy of these size estimations, which indicate that 83%–97% of the variability in dorsal shell length is predicted by umbo thickness and hinge length. Hinge length generated higher R2 values yet exhibited greater intra- and inter-observer error. While the predicted dorsal length for each species differed by region, this size difference was smaller than intra- and inter-observer error, suggesting broad applicability for these simple measurements. We applied these formulae to a Tseshaht First Nation archaeological clamshell assemblage (n = 488) on western Vancouver Island spanning 3000 years and observed profiles that resemble contemporary legal size limits, which suggests the sustained use and maintenance of local shellfisheries. The accuracy of these regression models for determining shell length from fragments highlights the utility of this approach as a basis for assessing past shellfish management practices.
  • OPEN ACCESS
    Burrow nests fall below critical temperatures of threatened seabirds but offer thermal refuge during extreme cold events
    FACETS • Vol. 9 • pp. 1 - 11
    Climate change is altering the severity and intensity of extreme weather events. Occupying microhabitats that buffer extreme weather may help species avoid harsh environmental conditions. We describe the thermal microclimate of Atlantic Puffin (Fratercula arctica) and Leach’s Storm-petrel (Hydrobates leucorhous) burrows and quantify whether burrows are thermal refuges during extreme cold weather events. We further test for the effect of weather conditions and burrow characteristics on nest microclimate and buffering capacity during extreme cold weather. We find that both species actively breed in burrow microclimates that are below their lower critical temperatures, which may impose significant thermoregulatory costs. However, burrows do act as thermal refuges because nests are kept 7.4–8.0 °C warmer than ambient temperatures during extreme cold weather events. Overall, external temperature and wind speed were strong drivers of burrow temperature, but burrow and habitat characteristics did not explain the variability in burrow buffering capacity during extreme cold weather. Our results suggest that burrows may provide a direct line of defence for seabird chicks against cold events. Given the complex responses of burrow microclimates to extreme events, quantifying how changes in environmental conditions will impact burrow-nesting seabirds in the future is key.
  • OPEN ACCESS
    The long-term effects of water resource development on blood mercury levels and the trophic ecology of Namew (lake sturgeon, Acipenser fulvescens)
    FACETS • Vol. 9 • pp. 1 - 13
    Water resource development can alter the movement and ecology of sturgeons. We studied total (THg) and methylmercury concentrations in whole blood sampled non-lethally from namew (Moose Cree L-dialect, lake sturgeon, Acipenser fulvescens), an endangered and culturally important subsistence fish. Namew were sampled from two tributaries within the Moose Cree Homeland: the Lower Mattagami River (an impacted system with four hydroelectric generating stations) and the North French River (a reference system that is free-flowing system with no development). Results indicated namew from the North French River had higher blood [THg] than those from the Mattagami River. Further modeling showed that trophic position was the primary driver of these differences, with North French namew having the highest nitrogen isotope ratios. Based on further isotope modeling, crayfish were major components of namew diet at all sites, while other prey items differed between sites. Specifically, namew with unobstructed access to the lower watershed had notably more enriched isotope values when compared to the freshwater benthic macroinvertebrates sampled, implying that other prey not captured herein may contribute to their diets and [THg]. Overall, we found differences in namew’s trophic ecology but no elevation in blood mercury levels at a site impacted by hydroelectric operations 60+ years post-impoundment.
  • OPEN ACCESS
    A pilot bioavailable strontium isotope baseline map of Southern British Columbia, Canada
    FACETS • Vol. 9 • pp. 1 - 11
    Strontium isotopes are used for provenience and mobility studies in archaeology, ecology, and forensic studies, and rely on accurate baseline maps that are used to compare and interpret human and animal strontium ratios. Here, we present a bioavailable 87Sr/86Sr map, also called an isoscape, for southern British Columbia derived from modern plant samples’ 87Sr/86Sr ratios. We sampled 67 medium root depth plants over a 900 km transect from the southern BC coast to inland BC to capture the natural 87Sr/86Sr ratios of plants along the four major geological belts in British Columbia. Non-parametric Kruskal–Wallis and pairwise Wilcox tests were used to examine whether the geological belts had statistically significant mean differences. It was found that the province could be effectively divided into east and west, with the Coastal–Intermontane and Omineca–Foreland regions having statistically different means from each other. 87Sr/86Sr ratios had statistically significant relationships with salt deposition, volcanic deposition, and mean age of the underlying lithology. Generally, 87Sr/86Sr ratios increased with distance from the coast as the atmospheric input of radiogenic strontium from marine-derived rainwater decreased and the input of radiogenic strontium isotopes from the underlying geology of the Rockies in the far east of the province increased.
  • 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
    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
    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.