The Canadian Field-Naturalist (E-Journal)
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Additions to the lichens, allied fungi, and lichenicolous fungi of the Ottawa region in Ontario and Quebec, with reflections on a changing biota
Get PDFThe inventory of lichens, allied fungi, and their parasites in the Ottawa region has grown from 391 in 1988 to 543 today, almost entirely because of the discovery of species overlooked in previous years and the inclusion of fungal parasites. In addition, almost 140 names have changed with reclassifications and re-identifications. These changes are presented here together with a list of synonyms updating the 1988 list. Vouchers are cited for all new records, and notes are presented for many species neither described nor keyed out in easily accessible literature. Reference is made to the new, complete list of lichens and lichenicolous fungi available online. The new checklist includes one species new for North America (Tremella christiansenii); five species and one variety new for Canada (Caloplaca parvula, Caloplaca reptans, Cladonia petrophila, Enchylium tenax var. ceranoides, Leprocaulon adhaerens, and Merismatium peregrinum); four new for Ontario (Caloplaca reptans, Kiliasia tristis, Lempholemma chalazanum, and Rinodina fimbriata); and nine new for Quebec (Arthonia helvola, Arthonia hypobela, Caloplaca parvula, Cladonia petrophila, Lempholemma chalazanum, Leprocaulon adhaerens, Merismatium peregrinum, Rimularia badioatra, and Tremella christiansenii). Although the climate of the region is warming, especially with higher minimum temperatures in winter, the lichen biota has not increased as a result but, in fact, may be threatened by the effects of climate change on the health of the forests and the trees that support lichens. Air quality has improved in recent decades, allowing numerous lichens to again become established in urban areas. Local areas of especially rich lichen diversity can be found on both the Ontario and Quebec sides of the region, and some of these “hot-spots” are mentioned. Other factors influencing the decrease or increase of lichen cover are also discussed
Vocal repertoire, harmonic structure, and behavioural context in Red-throated Loon (Gavia stellata)
Get PDFAmong the five loon species (Gaviidae), Red-throated Loon (Gavia stellata) is the oldest lineage and is the most divergent in morphology and vocalizations. We substantially expand earlier description of calls for a nesting pair and non-breeding birds on Haida Gwaii, British Columbia, Canada. Three major calls used by the nesting pair (Quack, Wail, Plesiosaur) were all low frequency (700–3000 Hz) with multiple harmonics, calls that were also used by non-breeding birds without territories that overnight on freshwater lakes. Call duetting in the Wail and Plesiosaur, as well as sexually dimorphic frequencies and structure within the duets, typically occur in territorial display or pair interactions. The nesting pair used several calls audible only at short distances (Coo, Extended Coo, Staccato, Soft Raack) that were low frequency (200–1200 Hz), graded in behavioural intensity and that resulted in chick responses, including feeding or return to nest. A high amplitude Loud Raack was used by the female and is associated with flight incentives for pre-fledged chicks. Vocalizations of chicks, usually feeding solicitations to the adults, develop from simple chirps in the first week following hatch to more complex calls resembling the Wail and the Plesiosaur calls just prior to fledging. Although the majority of our acoustical descriptions are limited to a single nesting pair where sexes could be differentiated, these represent the first quantification of sound frequency, harmonic structure, and duration, most often associated with context-specific responses, and are suggestive of syntactical content to the vocal repertoire of this basal taxon
Predation of a brown bat (Vespertilionidae) by a Green Frog (Lithobates clamitans) in Ontario, Canada
Get PDFOn 31 July 2019, a Green Frog (Lithobates clamitans) was observed consuming a Big Brown Bat (Eptesicus fuscus) at Meux Creek, Neustadt, Ontario. The bat was likely roosting at a nearby undercut bank when it was predated by the frog, which required nearly 90 min to consume its prey. This is the first record of a Green Frog consuming a bat species in Canada
Salt marsh width positively affects the occurrence of Least and Pectoral Sandpipers in the St. Lawrence River Estuary during fall migration
Get PDFSalt marshes are vulnerable to climate change-associated sea-level rise and storm-induced surges. Their degradation will likely affect shorebirds relying on this ecosystem. Least Sandpiper (Calidris minutilla) and Pectoral Sandpiper (Calidris melanotos) migrating along coastline habitats typically use salt marshes to rest and replenish their body reserves. Our objective was to test if width of the different vegetation zones within salt marshes affects the occurrence of Least and Pectoral Sandpipers stopping along the St. Lawrence River Estuary, Quebec, Canada, during fall migration. We established 26 survey sites, each 600 m in length, along the shoreline. Shorebird surveys were conducted in 2011 and 2012. We characterized salt marshes by measuring the width of each vegetation zone (lower marsh and upper marsh). We analyzed shorebird presence/not detected data with generalized estimating equations to test the predictions that occurrence of Least Sandpipers and Pectoral Sandpipers increases with width of both the lower and upper marsh. Upper marsh width was positively associated with probability of occurrence in each species. Our results highlight the importance of protecting the integrity of salt marshes for these two species. In the St. Lawrence River Estuary, where landward migration of salt marshes is no longer possible (coastal squeeze), effective management of shorelines is much needed. Otherwise, salt marshes and these two species could be locally jeopardized
"Yellowstone Wolves: Science and Discovery in the World’s First National Park" edited by Douglas W. Smith, Daniel R. Stahler, and Daniel R. MacNulty, 2020. [book review]
Get PDFNesting ecology and reuse of nest burrows by Bank Swallow (Riparia riparia) in southern Yukon
Get PDFBank Swallow (<i>Riparia riparia</i>) is a declining insectivorous bird that nests colonially in near-vertical surfaces, including natural banks along waterways as well as those created by industrial excavation. Several threats are likely contributing to the population decline, conservation measures have been recommended, and monitoring methods have been developed. However, little is known of this species in the extensive boreal portion of its breeding range. To assess whether recommendations developed in southern areas are likely to be effective in a more northerly region, we investigated aspects of the nesting ecology of Bank Swallow in southern Yukon during 2013–2017. Nesting activity occurred between 20 May and 21 August. We found an exceptional abundance of nest burrows in natural riverbanks along 46 km of the Yukon River near Whitehorse (326 burrows/km), but relatively low percent burrow occupancy in both natural and artificial habitats compared to studies from other regions. Year-to-year persistence of nest burrows and rates of reuse of burrows were high compared to other studies. We highlight the potential importance of the boreal region for recovery of Bank Swallow in Canada, and the importance of using region-specific estimates of percent occupancy when monitoring Bank Swallow using burrow counts. Further study is needed to determine whether unoccupied burrows contribute to nesting success, and whether there are situations in which Bank Swallow burrows should be protected year-round instead of only during nesting
