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  • OPEN ACCESS
    Julie Morand-Ferron retrospective (1977–2022) for FACETS
    FACETS • Vol. 9 • pp. 1 - 4
  • 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
    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
    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.