Abundance and occupancy of the western yellow-billed cuckoo (Coccyzus americanus) in Sonora, Mexico
Canadian Journal of Zoology, Ahead of Print. Unveiling factors that determine abundance and distribution of endangered wildlife species has important implications for their conservation across international boundaries. For instance, the Western Distinct Population (as defined by the U.S. Fish and Wildlife Service) of the yellow-billed cuckoo Coccyzus americanus (Linnaeus, 1758) has disappeared in most of the species ’ range across western United States and southwestern Canada but little is known about the conservation status at the southern edge of its breeding distribution in Mexico. To fill this information gap, we est...
Source: Canadian Journal of Zoology - April 20, 2023 Category: Zoology Authors: Alberto Mac ías-Duarte Edwin Ju árez Eduardo S ánchez Murrieta E. Leonel Perales-Hoeffer Carmen I. Ortega Rosas Source Type: research
Disease ecology of bats —the Canadian scene
Canadian Journal of Zoology, Ahead of Print. Bats are hosts to a range of pathogens, which include zoonotic pathogens and pathogens of conservation concern. Brock Fenton ’s research on bat ecology has always balanced clear communication of potential health risks associated with bats and the need to communicate these risks precisely to avoid unnecessary persecution of bats. Here, we integrate Brock’s work in the field of disease ecology with that of his students and collaborators and consider the potential advantages of studying disease ecology of bats within the Canadian context. The broad distribution of a few common ...
Source: Canadian Journal of Zoology - April 17, 2023 Category: Zoology Authors: Christina M. Davy Craig K.R. Willis Source Type: research
Relationship between food grinding and gut microbiota in Brandt's voles
Canadian Journal of Zoology, Ahead of Print. Food grinding is an abnormal behavior in rodents and its influencing factors are unknown. Our study investigated the potential relationships between gut microbiota and food grinding in Brandt's voles (Lasiopodomys brandtii (Radde, 1861)) by comparing the differences between groups with different degrees of food grinding. The strong food-grinding group showed more relative food ground, higher ratio of ground food to food consumption, and lower percentage of time spent in the central area. The structure of fecal microbiota community differed between the strong and weak food-grindi...
Source: Canadian Journal of Zoology - April 12, 2023 Category: Zoology Authors: Qiu-Yi Shen Jia-Yi Shi Ke-Han Gu Wan-Hong Wei Sheng-Mei Yang Xin Dai Source Type: research
A new species of Astyanax (Characiformes, Characidae) from the rio Apiac ás, rio Teles Pires basin, with a discussion on its phylogenetic position
Canadian Journal of Zoology, Ahead of Print. A new species of Astyanax Baird& Girard, 1854 is described from the rio Apiac ás, a tributary of the rio Teles Pires, rio Tapajós basin, Mato Grosso state, Brazil. The new taxon can be distinguished from all congeners, except those belonging to the Astyanax bimaculatus species group and to the Astyanax orthodus species group, by the presence of a horizontally elongated to r ounded humeral blotch. The new taxon can be readily distinguished from all species belonging to the A. bimaculatus species group and to the A. orthodus species group by presenting a distinct morphology ...
Source: Canadian Journal of Zoology - April 10, 2023 Category: Zoology Authors: Katiane M. Ferreira Fl ávio C.T. Lima Alexandre C. Ribeiro Nelson Flausino Junior Francisco A. Machado Juan Marcos Mirande Source Type: research
Marine and freshwater centrohelid heliozoans (Haptista: Centroplasthelida) in Canada, including taxonomic revisions and descriptions of 22 new species and subspecies
Canadian Journal of Zoology, Ahead of Print. Canadian coastal waters of the Pacific Ocean and the Atlantic Ocean as well as inland freshwater habitats in Ontario were sampled for centrohelid heliozoans (free-living heterotrophic single-celled organisms) over a period of nearly five decades. More than 60 species and subspecies were revealed, including 1 Triangulopteris, 1 Raphidocystis, 2 Pseudoraphidocystis, 3 Raineriophrys, 4 Pseudoraphidiophrys, 12 Choanocystis, 15 Pterocystis, and 25 Acanthocystis taxa. Of these, 22 were officially named and described as new to science based primarily on the morphology of the siliceous ...
Source: Canadian Journal of Zoology - March 27, 2023 Category: Zoology Authors: Kenneth H. Nicholls Source Type: research
Functional histology of the integument of the thin-spined porcupine, Chaetomys subspinosus
This study examines the functional histology of the thin-spined porcupine's (Chaetomys subspinosus (Olfers, 1818)) quills and integument, and compares them with the North American porcupine (Erethizon dorsatum (Linnaeus, 1758)) equivalents. Erethizon quills disseminate warnings to potential predators. An olfactory warning is generated by sebaceous glands of the lower back, disseminated by osmetrichial specializations of lower-back quills. Chaetomys skin lacks functional sebaceous glands, and generates no warning odor. Erethizon quills also carry a visual warning, effective even in dim light. Chaetomys quills carry no warni...
Source: Canadian Journal of Zoology - March 22, 2023 Category: Zoology Authors: David M. Chapman Gast ón Andrés Fernandez Giné Uldis Roze Source Type: research
A new species of Cambeva (Siluriformes: Trichomycteridae) from an area of high anthropogenic impacts in the headwaters of Rio Igua çu, Southern Brazil
Canadian Journal of Zoology, Ahead of Print. Cambeva piraquara, sp. nov., a restricted-range and rare species last collected from over 20 years ago, is described from the Rio Piraquara, upper Rio Igua çu basin, Rio Paraná (La Plata) system. The new species is distinguished from all congeners by having two conspicuous dark-brown longitudinal stripes on the inner skin layer of body over a plain yellowish background: a conspicuous wide and well-defined dark-brown longitudinal mid-lateral stripe ex tending from the opercular patch of odontodes to the first third of caudal-fin rays and a dorso-sagittal stripe comprising large...
Source: Canadian Journal of Zoology - March 20, 2023 Category: Zoology Authors: Renan B. dos Reis Wolmar B. Wosiacki Juliano Ferrer Laura M. Donin Weferson J. da Gra ça Source Type: research
Western Rattlesnake (Crotalus oreganus) spring migration in British Columbia: a comparative study of juveniles and adults
We examined and compared spring outbound migratory movements of juveniles and adults at a site in southern British Columbia, Canada, using radiotelemetry data collected between 2011 and 2016 (adult snakes) and in 2021 (juvenile snakes). We found that compared with adult rattlesnakes, juveniles displayed similar directional orientation, direction of vertical migration, and path sinuosity, but initiated spring migrations later and exhibited shorter movements in terms of distances and rates. For example, juvenile straight-line migration distance (262 ± 90 m) was significantly shorter than that for adults (1069 ± 134 m; P&...
Source: Canadian Journal of Zoology - March 17, 2023 Category: Zoology Authors: Chloe R. Howarth Christine A. Bishop Karl W. Larsen Source Type: research
Ultrastructure of an opecoelid daughter sporocyst, Podocotyle sp. (Digenea: Opecoelidae): comparative analysis of the somatic tissues and new insights into the organization of the nervous system
Canadian Journal of Zoology, Ahead of Print. Digenea is a group of widespread parasitic flatworms with a complex life cycle including a successive change of parthenogenetic and hermaphroditic generations. Daughter sporocysts are among the least studied parthenitae in terms of the ultrastructure of their body wall and nervous system. Here we present an ultrastructural and immunocytochemical study of Podocotyle sp. daughter sporocyst (Opecoelidae), parasitizing in Littorina obtusata Linnaeus, 1758 from the White Sea. Our results focus on the structure of the body wall, birth pore, excretory and nervous systems, and include n...
Source: Canadian Journal of Zoology - March 16, 2023 Category: Zoology Authors: Sofia A. Denisova Natalia N. Shunatova Vladimir V. Lebedenkov Sergei V. Shchenkov Source Type: research
Of mice, ticks, and fleas: host behaviour and co-occurring parasites
This study suggests that co-occurring parasite species (ticks and fleas) may differentially affect their host's behaviour depending on the presence/absence of the other parasite on the host. Alternatively, host behaviour may differentially affect individual susceptibility to being infested with ticks, fleas, or both. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - March 16, 2023 Category: Zoology Authors: Merlin Caron-L évesque Vincent Careau Source Type: research
The evolution of sanguivory in vampire bats: origins and convergences
Canadian Journal of Zoology, Ahead of Print. Blood-feeding (sanguivory) has evolved more than two dozen times among birds, fishes, insects, arachnids, molluscs, crustaceans, and annelids; however, among mammals, it is restricted to the vampire bats. Here, the authors revisit the question of how it evolved in that group. Evidence to date suggests that the ancestors of phyllostomids were insectivorous, and that carnivory, omnivory, and nectarivory evolved among phyllostomids after vampire bats diverged. Frugivory likely also evolved after vampire bats diverged, but the phylogeny is ambiguous on that point. However, vampire...
Source: Canadian Journal of Zoology - March 13, 2023 Category: Zoology Authors: Daniel K. Riskin Gerald G. Carter Source Type: research
Prehibernation swarming in temperate bats: a critical transition between summer activity and hibernation
Canadian Journal of Zoology, Ahead of Print. In this contribution to Dr. Brock Fenton's Festschrift, we briefly reflect on Dr. Fenton's seminal works examining bat swarming behaviour in Ontario and use these reflections as a launch pad to conduct a global review on autumn swarming in bats, and underlying hypotheses to explain this behaviour. Our review frames the swarming period as a time of critical transitions, during which bats must balance multiple life history trade-offs, and we consider how various intrinsic and extrinsic factors may contribute to inter- and intraspecific differences in autumn behaviour. We discuss t...
Source: Canadian Journal of Zoology - February 28, 2023 Category: Zoology Authors: Erin E. Fraser Liam P. McGuire Source Type: research
Are riparian habitats always more diverse than nonriparian? A case study with small mammals in a rainforest environment
Canadian Journal of Zoology, Ahead of Print. Riparian environments are characterized by a gradient of environmental factors perpendicular to the watercourse, as the habitat changes from terrestrial to aquatic. These areas are highly diverse in comparison with adjacent ecosystems specially in arid and semi-arid regions, a pattern that may not be as marked in other climates where humidity and nutrient gradients are not so abrupt. We aimed to evaluate the diversity of small mammals in riparian and nonriparian environments in an area of Atlantic Forest, as well as the association between habitat structure and small mammal asse...
Source: Canadian Journal of Zoology - February 17, 2023 Category: Zoology Authors: Rodrigo Paulo da Cunha Ara újo Maron Galliez Helena Godoy Bergallo Source Type: research
First account of apparent alloparental care of a long-finned pilot whale calf (Globicephala melas) by a female killer whale (Orcinus orca)
Canadian Journal of Zoology, Ahead of Print. Interactions between killer whales (Orcinus orca (Linnaeus, 1758)) and long-finned pilot whales (Globicephala melas (Traill, 1809)) have been documented on numerous occasions, usually involving predation events and pursuits. Here, the first documented account of a long-finned pilot whale calf seen in echelon position with one killer whale in a group of three killer whales is described, along with one further interaction of the same killer whale group with other long-finned pilot whales. Behavioral, locational, and photographic data were recorded and analyzed for killer whales be...
Source: Canadian Journal of Zoology - February 17, 2023 Category: Zoology Authors: Marie-Th érèse Mrusczok Elizabeth Zwamborn Menja von Schmalensee Sara Rodr íguez Ramallo Robert A. Stefansson Source Type: research
Two new species of miniature tetras of the fish genus Priocharax from the Rio Juru á drainage, Acre, Brazil (Teleostei: Characiformes: Characidae)
We describe a remarkable sexual dimorphism of the pelvic girdle of Priocharax toledopizae in which the pelvic musculature is enlarged forming a pedicel for the fin in mature males. Most localities where these species were found suffer from significant degradation mainly due to litter accumul ation and suppression of the riparian forest, raising concerns about their conservation status. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - February 10, 2023 Category: Zoology Authors: George M.T. Mattox Ralf Britz Camila S. Souza Andr é L.S. Casas Fl ávio C.T. Lima Claudio Oliveira Source Type: research
