The Canadian Field-Naturalist (E-Journal)
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Diversity and conservation status of lichens and allied fungi in the Greater Toronto Area: results from four years of the Ontario BioBlitz
Get PDFBioblitzes are typically 24-hour biological surveys of a defined region carried out by taxonomic specialists, citizen scientists, and the general public. The largest in Canada is the Ontario BioBlitz, an annual event held in the Greater Toronto Area (GTA). Between 2013 and 2016, we examined the feasibility of including lichens and allied fungi in the Ontario BioBlitz. These taxa are often overlooked, understudied, and taxonomically difficult. We completed a bioblitz in each of the four major watersheds in the GTA and recorded 138 species in 72 genera which, combined with all previous collections, totals 180 species in 88 genera in the area. Thirteen of the species we collected are provincially ranked as S1 (critically imperilled), S2 (imperilled), or S3 (vulnerable). We collected Lecanora carpinea for the first time in Ontario. Our results provide a baseline list of GTA lichens that can be used for monitoring. This is one of the first detailed lichen surveys of a major North American urban area and it demonstrates that rapid bioblitz surveys are proficient in capturing lichen diversity despite their inconspicuous nature and the advanced microscopy and chemical analyses required for their identification.
Distribution and taxonomy of Isoetes tuckermanii subsp. acadiensis, comb. nov. (Isoetaceae) in North America
Get PDFIsoetes acadiensis is an emergent aquatic lycophyte of freshwater shores found in a narrow range along the Atlantic coast of northeastern North America where it frequently coexists with Isoetes tuckermanii (sensu stricto [s. str.]). Apparently fertile plants with intermediate morphology occur commonly in mixed populations. No sterile hybrids between the two taxa have been detected. Although I. acadiensis maintains a distinctive geographic distribution (within and smaller than that of I. tuckermanii [s. str.]), exhibits molecular evidence of genetic distinctiveness, and has morphologically distinctive features in most populations, the weight of evidence suggests it is not distinct from I. tuckermanii at a species level. Accordingly, I. tuckermanii subsp. acadiensis, comb. nov. is proposed as the appropriate designation for this biogeographically important Acadian endemic
A practical technique for preserving specimens of duckmeal, Wolffia (Araceae)
Get PDFMaking identifiable herbarium vouchers of the minute aquatic vascular plant duckmeal, Wolffia (Lemnoideae; Araceae) has typically required plants to be preserved in transparent, space-consuming vials that are fragile, difficult to work with, and labourious to prepare. An alternative technique for dry-mounting Wolffia within a layer of transparent, acid-free glue presents a promising alternative. Although the largely water-filled individual plants still compress substantially, this preparation technique results in specimens that retain their colour, size, and, most important, their shape. This greatly enhances the possibility of confident identification and simplifies both specimen preparation and storage
Japanese Chaff-flower, Achyranthes japonica (Amaranthaceae), on the Erie islands, an invasive plant new to Canada
Get PDFJapanese Chaff-flower, Achyranthes japonica (Miquel) Nakai (Amaranthaceae) was found growing on two islands in western Lake Erie: East Sister Island and Middle Island. These are the first documented reports for this species in Canada, and these locations are approximately 300 km north of the nearest reported observations in southern Ohio. Japanese Chaff-flower is a non-native plant from Asia, which is highly invasive in the United States and has the potential to become so in Canada
"The Birds at My Table: Why We Feed Wild Birds and Why It Matters" by Darryl Jones, 2018. [book review]
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"Mammal Tracks and Sign: A Guide to North American Species. Second Edition" by Mark Elbroch with contributions by Casey McFarland, 2019. [book review]
Get PDFSpring food habits of Wolverine (Gulo gulo) in the Colville River watershed, Alaska
Get PDFWolverines (Gulo gulo) are relatively abundant on the North Slope of Alaska, an Arctic ecosystem dominated by tundra habitats that run north from the Brooks Range across a wide coastal plain to the Beaufort Sea. The region contains a range of potential Wolverine prey species, including ungulates (Caribou [Rangifer tarandus], Moose [Alces americanus]), Arctic Ground Squirrel (Urocitellus parryii), and both Soricidae and Cricetidae species. The seasonal composition of these, and other prey species, in the Wolverines’ diet is not well understood. We collected Wolverine scats during spring (March–May) on the North Slope while tracking animals from snowmobiles and with helicopters that visited areas identified as of interest during ground surveys or using global positioning system collared animals. We analyzed prey remains in 48 scat samples based on hair, bone, and other prey fragments. We then calculated frequency of occurrence, percentage of occurrence, and weighted percent volume for each major prey category detected. We confirmed species identity of scats as Wolverine by amplifying the control region of the mitochondrial DNA. We estimated spring diet diversity and richness based on nine major prey categories detected in scats. Ungulates and cricetids together constituted 69% of the Wolverines’ spring diet, with Snowshoe Hare (Lepus americanus) constituting 9%, fox (Vulpes spp.) 6%, Arctic Ground Squirrel 2%, birds 2%, American Beaver (Castor canadensis) less than 1%, and unknown 6%
Body mass as an estimate of female body condition in a hibernating small mammal
Get PDFIn hibernating squirrels, the amount of energy stored as fat may influence several important demographic traits, but is difficult to quantify in living animals. Thus, several non-destructive indices of body condition are used, including simple indices that use body mass and scaled indices that correct body mass for structural size. However, the accuracy of these indices for hibernating squirrels is poorly known. We used measurements of total body electrical conductivity (TOBEC) from adult female Golden-mantled Ground Squirrels (Callospermophilus lateralis) to characterize body composition (lean mass versusfat mass) and condition (fat stores) at multiple stages in the circannual cycle. Body mass explained a high proportion of the variation in fat mass during the emergence and pre-hibernation stages, but less during the reproduction stage. Contrary to expectation, correcting for structural size did not markedly improve the condition index. Our results suggest that body mass is a good estimate of body condition during the periods of emergence and pre-hibernation fattening, and therefore may be useful to predict important components of fitness such as reproductive success and overwinter survival