The Canadian Field-Naturalist (E-Journal)
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Diet of cisco (Coregonus spp.) in Algonquin Park region lakes: variation among forms
Efforts to conserve cisco (Coregonus spp.) diversity in Canadian lakes have been impeded by the unresolved taxonomy of North American ciscoes. When a strictly taxonomic-based approach is not possible, conservation units of infraspecific diversity can be identified using biological, morphological, ecological, and genetic evidence. Distinct cisco forms have been reported from deep oligotrophic lakes within boundaries of the historical outflow of glacial Lake Algonquin. In this study, we described the diet of three cisco forms netted from eight lakes located in or adjacent to Algonquin Provincial Park, Ontario. Opossum Shrimp (Mysis diluviana) was the dominant prey of benthic, low gill raker count forms in Trout and White Partridge Lakes, and of a large-bodied, high gill raker count form in Hogan Lake. Zooplankton was the most important prey item of small-bodied, pelagic forms in White Partridge Lake, and Cisco (Coregonus artedi) collected from five other Algonquin Park lakes. The diet of Trout Lake Cisco was a broader mix of prey items, including chironomid pupae, Opossum Shrimp, phantom midges (Chaboridae spp.), and zooplankton. Our study provides strong dietary evidence of the special ecological context occupied by cisco forms in White Partridge Lake, and moderate evidence for Trout Lake. Past reports of Shortjaw Cisco (Coregonus zenithicus) in six of the study lakes were not supported by our sampling, because low gill raker count forms were not captured
Litter-dwelling terrestrial molluscs of Nepisiguit Protected Natural Area and Mount Carleton Provincial Park, north-central New Brunswick
No comprehensive study of the terrestrial gastropod fauna of northern New Brunswick has previously been undertaken. Most terrestrial gastropod molluscs are tiny and generally live unnoticed under debris, in leaf litter, and among other dead and living vegetation. Sifting and sorting collected samples of leaf litter are effective in sampling snails. In June–July 2015 and August 2016, 43 samples of forest leaf litter were collected in Nepisiguit Protected Natural Area and Mount Carleton Provincial Park. These samples yielded 22 species of terrestrial gastropods. Seven species are reported from New Brunswick for the first time.Il n’y a pas eu d’étude exhaustive de la faune gastéropode terrestre du nord du Nouveau-Brunswick. La plupart des mollusques gastéropodes terrestres sont minuscules et vivent généralement inaperçus sous les débris, dans la litière de feuilles et d’autres végétaux morts et vivants. Le tamisage et le tri des échantillons prélevés de litière de feuilles sont efficaces pour échantillonner les escargots. En juin–juillet 2015 et en août 2016, 42 échantillons de litière de feuilles forestières ont été prélevés dans l’zone naturelle protégée Nepisiguit et le parc provincial Mont-Carleton. Ces échantillons ont donné 22 espèces de gastéropodes terrestres. Sept espèces sont rapportées au Nouveau-Brunswick pour la première fois
Recent records of myxomycetes from New Brunswick, Canada
Studies of the diversity of myxomycetes or plasmodial slime moulds (Amoebozoa) in New Brunswick are lagging behind those of many other groups of terrestrial organisms. Here, we summarize the myxomycetes of the province as documented by recently collected specimens held by the New Brunswick Museum (NBM). Between 2007 and 2019, 264 specimens were collected, representing 80 species in 29 genera. Most of these records result from targetted searching during NBM-led biodiversity surveys (the BiotaNB project) in provincial protected natural areas between 2014 and 2019 and a mycological foray on Campobello Island in 2016. Previously, only seven species had been reported for the province. Consistent with their worldwide distributions and abundance, Arcyria cinerea, Fuligo septica, Ceratiomyxa fruticulosa, and Lycogala epidendrum were the most collected species, whereas the globally rare species Paradiacheopsis microcarpa has been collected in New Brunswick six times. Forty-two species were found only once, and five of these (Comatricha mirabilis, Fuligo laevis, Hemitrichia chrysospora, Lepidoderma neoperforatum, Listerella paradoxa) are rare worldwide