Faculty & Staff Research

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Browsing Faculty & Staff Research by Subject "Forestry and Environmental Management"

Now showing 1 - 4 of 4
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    Genomic population structure of Striped Bass (Morone saxatilis) from the Gulf of St. Lawrence to Cape Fear River
    (Wiley Open Access, 2020-07-14) LeBlanc, Nathalie M.; Gahagan, Benjamin I.; Andrews, Samuel N.; Avery, Trevor S.; Puncher, Gregory N.; Reading, Benjamin J.; Buhariwalla, Colin F.; Curry, R. Allen; Whiteley, Andrew R.; Pavey, Scott A.
    Striped Bass, Morone saxatilis (Walbaum, 1792), is an anadromous fish species that supports fisheries throughout North America and is native to the North American Atlantic Coast. Due to long coastal migrations that span multiple jurisdictions, a detailed understanding of population genomics is required to untangle demographic patterns, understand local adaptation, and characterize population movements. This study used 1,256 single nucleotide polymorphism (SNP) loci to investigate genetic structure of 477 Striped Bass sampled from 15 locations spanning the North American Atlantic coast from the Gulf of St. Lawrence, Canada, to the Cape Fear River, United States. We found striking differences in neutral divergence among Canadian sites, which were isolated from each other and US populations, compared with US populations that were much less isolated. Our SNP dataset was able to assign 99% of Striped Bass back to six reporting groups, a 39% improvement over previous genetic markers. Using this method, we found (a) evidence of admixture within Saint John River, indicating that migrants from the United States and from Shubenacadie River occasionally spawn in the Saint John River; (b) Striped Bass collected in the Mira River, Cape Breton, Canada, were found to be of both Miramichi River and US origin; (c) juveniles in the newly restored Kennebec River population had small and nonsignificant differences from the Hudson River; and (d) tributaries within the Chesapeake Bay showed a mixture of homogeny and small differences among each other. This study introduces new hypotheses about the dynamic zoogeography of Striped Bass at its northern range and has important implications for the local and international management of this species.
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    Movements of juvenile and sub-adult striped bass Morone saxatilis in the Saint John River, New Brunswick, Canada
    (Inter-Research, 2020-11-05) Andrews, S.N.; Linnansaari, T.; Leblanc, N.M.; Pavey, S.A.; Curry, R.A.
    Juvenile striped bass (age-1) of distinct genetic ancestry were re-discovered in the Saint John River, New Brunswick in 2014 after a 35 yr hiatus of recognition. These juveniles were determined to be highly genetically divergent from all possible source populations, hypothesized to be of Saint John River ancestry, and thus considered evidence of the continued existence of the native stock. Successful recruitment of strong year classes of striped bass within the Saint John River, however, appears to be infrequent. We acoustically tagged and tracked juvenile and sub-adult striped bass (n = 37; age 2-4) in the Saint John River in both 2015 and 2016, and identified summer feeding and overwintering habitats that established an in-river residency. Following decades of poor or no recruitment of the native striped bass stock, it is now imperative that managers quickly include monitoring of juvenile and sub-adult striped bass and protection of their habitats in the conservation and recovery efforts for Saint John River striped bass.
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    Native Woods of New Brunswick - An Historical Glimpse of Canadian Forestry
    (2000-03-22) Savidge, Rodney, Arthur
    An artifact in book form of wood specimens produced from the Acadian Forest in 1861 is described and considered in relation to tree and shrub diversity within New Brunswick. Specimen names in this ‘wood book’ reveal problems in species nomenclature and classification that continue to affect forest management practices in Canada. Analysis of the historical setting prompted reflections about conservation, physiological diversity, silviculture, forestry education and tree science in relation to sustaining future survival fitness in trees.
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    The effects of taxonomy, diet, and ecology on the microbiota of riverine macroinvertebrates
    (Wiley Open Access, 2020-12-29) Kroetsch, Shawn A.; Kidd, Karen A.; Monk, Wendy A.; Culp, Joseph M.; Compson, Zacchaeus G.; Pavey, Scott A.
    Freshwater macroinvertebrates play key ecological roles in riverine food webs, such as the transfer of nutrients to consumers and decomposition of organic matter. Although local habitat quality drives macroinvertebrate diversity and abundance, little is known about their microbiota. In most animals, the microbiota provides benefits, such as increasing the rate at which nutrients are metabolized, facilitating immune system development, and defending against pathogenic attack. Our objectives were to identify the bacteria within aquatic invertebrates and determine whether their composition varied with taxonomy, habitat, diet, and time of sample collection. In 2016 and 2017, we collected 264 aquatic invertebrates from the mainstem Saint John (Wolastoq) River in New Brunswick, Canada, representing 15 orders. We then amplified the V3-V4 hypervariable region of the 16S rRNA gene within each individual, which revealed nearly 20,000 bacterial operational taxonomic units (OTUs). The microbiota across all aquatic invertebrates were dominated by Proteobacteria (69.25% of the total sequence reads), but they differed significantly in beta diversity, both among host invertebrate taxa (genus-, family-, and order-levels) and temporally. In contrast to previous work, we observed no microbiota differences among functional feeding groups or traditional feeding habits, and neither water velocity nor microhabitat type structured microbiota variability. Our findings suggest that host invertebrate taxonomy was the most important factor in modulating the composition of the microbiota, likely through a combination of vertical and horizontal bacterial transmission, and evolutionary processes. This is one of the most comprehensive studies of freshwater invertebrate microbiota to date, and it underscores the need for future studies of invertebrate microbiota evolution and linkages to environmental bacteria and physico-chemical conditions.