Genomic Evaluation of the Genus Coltivirus Indicates Genetic Diversity among Colorado Tick Fever Virus Strains and Demarcation of a New Species

The type species of the genus Coltivirus, Colorado tick fever virus (CTFV), was discovered in 1943 and is the most common tick-borne viral infection in the Western US. Despite its long history, very little is known about the molecular diversity of viruses classified within the species Colorado tick fever coltivirus. Previous studies have suggested genetic variants and potential serotypes of CTFV, but limited genetic sequence information is available for CTFV strains. To address this knowledge gap, we report herein the full-length genomes of five strains of CTFV, including Salmon River virus and California hare coltivirus (CTFV-Ca). The sequence from the full-length genome of Salmon River virus identified a high genetic identity to the CTFV prototype strain with >90% amino acid identity in all the segments except segment four, suggesting Salmon River virus is a strain of the species Colorado tick fever coltivirus. Additionally, analysis suggests that segment four has been associated with reassortment in at least one strain. The CTFV-Ca full-length genomic sequence was highly variable from the prototype CTFV in all the segments. The genome of CTFV-Ca was most similar to the Eyach virus, including similar segments six and seven. These data suggest that CTFV-Ca is not a strain of CTFV but a unique species. Additional sequence information of CTFV strains will improve the molecular surveillance tools and provide additional taxonomic resolution to this understudied virus.

Food web incorporation of marine-derived nutrients after the reintroduction of endangered inner Bay of Fundy Atlantic salmon (Salmo salar)

Inner Bay of Fundy Atlantic salmon (Salmo salar) are endangered anadromous fish that have the potential to provide marine-derived nutrients (MDNs) to freshwater ecosystems depending on their population abundance. Salmon have been reintroduced to the Upper Salmon River, but not the adjacent Point Wolfe River, in Fundy National Park, New Brunswick, Canada. This study determined whether stocking of adult salmon increased the productivity of the river. To examine the incorporation of MDNs, biofilm, leaf litter, Perlidae, Heptageniidae and brook trout (Salvelinus fontinalis) were sampled pre- and post-spawning in 2015-2017 from down- and up-stream of a natural barrier in both rivers and analyzed for carbon (δ13C) and nitrogen (δ15N) isotopes. After salmon spawning in each year, all organisms at the downstream site of the stocked river increased in δ13C and δ15N, with the greatest enrichment in brook trout (δ13C -23.97 to -21.10‰, δ15N +6.36 to +10.73‰). The proportion of MDNs in brook trout after salmon spawning (2015: 23.4%, 2016: 40.7%, 2017: 37.4%) also increased with higher numbers of released adult salmon. Results support the importance of salmon restoration for increasing the proportion of MDNs and productivity in rivers in Atlantic Canada.

Supplemental Material: Evolution of the Late Cretaceous Nanaimo Basin, British Columbia, Canada: Definitive provenance links to northern latitudes

<div>Item A: Summary of Nanaimo Group Detrital Zircon Samples (A1-A2). Item B: Biostratigraphic Age Control on Samples (B1-B10). Item C: Nanaimo Group Detrital Zircon Data (C1-C77). Item D: Nanaimo Group Conglomerate Clast Detrital Zircon Data (D1-D7). Item E: Nanaimo Group Muscovite Ar-Ar Geochronology (E1-E7). Item F: Nanaimo Group Lu-Hf Isotopic Data (F1-F7). Item G: Modern Salmon River Detrital Zircon Data (G1-G3).<br></div>

Supplemental Material: Evolution of the Late Cretaceous Nanaimo Basin, British Columbia, Canada: Definitive provenance links to northern latitudes

<div>Item A: Summary of Nanaimo Group Detrital Zircon Samples (A1-A2). Item B: Biostratigraphic Age Control on Samples (B1-B10). Item C: Nanaimo Group Detrital Zircon Data (C1-C77). Item D: Nanaimo Group Conglomerate Clast Detrital Zircon Data (D1-D7). Item E: Nanaimo Group Muscovite Ar-Ar Geochronology (E1-E7). Item F: Nanaimo Group Lu-Hf Isotopic Data (F1-F7). Item G: Modern Salmon River Detrital Zircon Data (G1-G3).<br></div>

Distribution, Drivers, and Threats of Aluminum in Groundwater in Nova Scotia, Canada

Increased rates of acid deposition derived from the burning of fossil fuels over the last century have resulted in the acidification and increase in aluminum (Al) levels in freshwaters and soils in sensitive areas. While the acidification of surface waters such as lakes and rivers has been extensively studied, the acidification status and resulting Al concentrations in groundwater are poorly understood. Here we aim to describe the distribution of Al in groundwater across the province of Nova Scotia, Canada. We investigate the hydrogeological conditions that influence Al concentrations in groundwater and compare Al concentrations to legislated threshold levels for human and aquatic health. We found groundwater Al concentrations to be highest in areas underlain by plutonic and metamorphic bedrock types as well as surficial aquifers, with pH and organic carbon concentrations having the strongest correlation with groundwater Al concentrations. Few samples exceed the maximum acceptable concentration of 2900 µg/L released by Health Canada (2021), but these exceedances are important to highlight given the challenges with respect to Al treatment in private domestic wells and our evolving understanding of Al impacts to human health. High concentrations of Al in groundwater may also be exported to surface waters such as rivers and lakes, where they can be harmful to aquatic populations such as Atlantic salmon (Salmo salar). We recommend that private well owners test their water supplies for Al, and that further studies on Al export from groundwater to surface water be carried out in the most high-risk areas coincident with important Atlantic salmon river watersheds.

A conflict between traditional flood measures and maintaining river ecosystems. A case study in river Lærdal, Norway

&lt;p&gt;Floods are among the most damaging natural disasters which are likely to increase with the effects of climate change and changes in land use. Therefore, rivers have been the focus of engineering for establishing structural flood mitigation measures. Traditional flood infrastructure, such as levees and dredging have threatened floodplains and river ecosystems and during the last decade, sustainable reconciliation of freshwater ecosystems is increasing. However, we still find many areas where these traditional measures are proposed and it is challenging to find tools for evaluations of different measures and quantification of the possible impacts. We propose the use of hydraulic modelling and remote sensing data for evaluation of different flood strategies and quantification of changes in hydraulic parameters in an ecological scale. This is applied in L&amp;#230;rdal River, in Norway, a national salmon river specially recognized by its environment for Atlantic salmon, where the Norwegian Water Resources and Energy Directorate (NVE) has proposed l flood measures that include confinement with walls and dredging in the riverbed. Results show that the constructing a higher wall could avoid dredging in the river bed resulting in a most cost-effective solution. Dredging could improve hydraulic conditions for juvenile salmon if applied as river restoration measure but channelization of the river would have big impacts in the river ecosystem.&lt;/p&gt;

Chinook salmon exhibit long-term rearing and early marine growth in the Fraser River, B.C., a large urban estuary

Estuaries represent a transition zone for salmon migrating from freshwater to marine waters, yet their contribution to juvenile growth is poorly quantified. Here, we use genetic stock identification and otolith analyses to quantify estuarine habitat use by Chinook salmon (<i>Oncorhynchus tshawytscha</i>) – the Pacific salmon species considered most reliant on this habitat – in Canada’s most productive salmon river, the Fraser. Two years of sampling revealed subyearling migrant (“ocean-type”) Chinook from the Harrison River to be the estuary’s dominant salmon population throughout the emigration period. These Chinook salmon were caught predominantly in the estuary’s brackish marshes but shifted to more saline habitats as they grew. Otolith analyses indicated that these Chinook salmon have wide-ranging entry timing (from February to May), and longer estuarine residency (weeks to months, mean 41.8 days) than estimated by prior studies, but similar daily growth rates (mean 0.57 mm +/- 0.13 SD) across entry dates and residency periods, implying sufficient foraging opportunities throughout the emigration period and habitats. Together, these results suggest that estuarine habitat is more important for early marine growth of subyearling migrant Chinook salmon than previously recognized.