Challenges in fish aging: the role of otolith preparation technique and experience level in aging lake whitefish (Coregonus clupeaformis)
Canadian Journal of Zoology, Ahead of Print. Lake whitefish (Coregonus clupeaformis (Mitchill, 1818)) is an important commercial and recreational species in the Great Lakes. Precise age estimates are important for management, and two widely used techniques for otolith preparation are thin-section and crack-and-burn, which have not been compared for lake whitefish. Sagittal otoliths were collected from 92 lake whitefish in Green Bay and Lake Michigan and aged using thin-section and crack-and-burn techniques. Otoliths were aged independently by three individuals (two novices and one expert) to assess repeatability in estimat...
Source: Canadian Journal of Zoology - September 26, 2022 Category: Zoology Authors: Madeline N. McKeefry Stefan R. Tucker Andrew L. Ransom Timothy G. Kroeff Patrick S. Forsythe Source Type: research
Petroleum-based and biodegradable microplastics alter tissue structure and fecundity in the eastern mudsnail (Ilyanassa obsoleta)
Canadian Journal of Zoology, Ahead of Print. Microplastics are hazardous to aquatic life. Most experiments focus on the effects of a single type of microbead, while in the environment, organisms are exposed to irregularly shaped fragments belonging to several chemical groups. The effects of biodegradable plastics are unknown. We tested the effects of mixed-source (MS) petroleum-based and biodegradable (polylactic acid, PLA) microplastics on the intertidal eastern mudsnail, Ilyanassa obsoleta (Say, 1822), a benthic grazer. MS plastics were collected from local coastal areas (polystyrene, polyethylene, polypropylene, polyvin...
Source: Canadian Journal of Zoology - September 22, 2022 Category: Zoology Authors: Ben Hewins Glenys Gibson Source Type: research
Are external head measurements a reliable predictor of brain size in the Common Quail (Coturnix coturnix)?
Canadian Journal of Zoology, Ahead of Print. Comparative research conducted during the past two decades revealed ecological and evolutionary consequences of interspecies differences in relation to brain size. However, relatively much fewer studies have focused on intraspecific variation in brain sizes. This may arise from the lack of a reliable and universal methodology to estimate brain size that can be employed in wild populations in vivo and in a minimally invasive manner. Here, we assessed whether variation in brain mass of Common Quails (Coturnix coturnix (Linnaeus, 1758)) was predicted by external measurements of the...
Source: Canadian Journal of Zoology - September 21, 2022 Category: Zoology Authors: Joanna T. Bialas Valeria Marasco Leonida Fusani Gianni Pola Marcin Tobolka Source Type: research
Space use and resource selection of Wood Turtles (Glyptemys insculpta) in the northeastern part of its range
Canadian Journal of Zoology, Ahead of Print. The threats that affect a species often vary within its geographic range. Wood Turtles (Glyptemys insculpta (Le Conte, 1830), formerly Clemmys insculpta (Le Conte, 1830)) are a species of concern due to widespread decline from anthropogenic threats. We studied two populations of Wood Turtles from June to September 2019 and 2020 to evaluate how landscape features and vegetative structure influenced space and habitat use and to identify potential risks in the remote, northern parts of its range. We hypothesized that space use would vary due to regional, landscape, and sex-specific...
Source: Canadian Journal of Zoology - September 20, 2022 Category: Zoology Authors: Sierra R. Latham Alexej P.K. Sir én Leonard R. Reitsma Source Type: research
Morphological and molecular characterization of the ciliate parasite Tetrahymena rostrata infecting the renal organ of the dusky slug (Arion fuscus)
Canadian Journal of Zoology, Ahead of Print. The histophagous ciliate Tetrahymena rostrata (Kahl, 1926) is a facultative parasite of the renal organ of land snails and slugs. The possibility of transovum transmission and the lack of heteroparental sex make T. rostrata an interesting model for studying host specificity and distribution patterns in pathogenic ciliates. We recorded mass Tetrahymena infection in the dusky slug (Arion fuscus (O.F. M üller, 1774)) collected in Slovakia, Central Europe. Based on the mitochondrial 16S rRNA gene and barcoding cytochrome c oxidase subunit I (COI) sequences, Slovak isolates belong t...
Source: Canadian Journal of Zoology - September 20, 2022 Category: Zoology Authors: Tengyue Zhang Peter V ďačný Source Type: research
Ecology and conservation of avian aerial insectivores
Canadian Journal of Zoology, Ahead of Print. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - September 19, 2022 Category: Zoology Authors: Kevin J. Kardynal Tara L. Imlay Source Type: research
Linking sexual size dimorphism to trophic niche partitioning in a generalist predator
Canadian Journal of Zoology, Ahead of Print. Sexual size dimorphism is a common phenomenon in mammals, and researchers have been trying to demonstrate the evolutionary causes leading to sexual dimorphism. Two main hypotheses emerged: (1) the sexual selection hypothesis and (2) the sexual competition hypothesis (also called resource partitioning hypothesis). Here, we attempted to link sexual dimorphism in fishers (Pekania pennanti (Erxleben, 1777)) with their fall diet using stable isotope profiling and body and skull measurements . We used the carcasses of 39 fishers which were caught in eastern Québec during fall 2014...
Source: Canadian Journal of Zoology - September 8, 2022 Category: Zoology Authors: J érôme Laliberté Ève Rioux R émi Lesmerises Martin-Hugues St-Laurent Source Type: research
Effects of physical restraint and endogenous adrenocorticotropin challenges on corticosterone levels and immunological indexes in the Broad-snouted Caiman (Caiman latirostris)
Canadian Journal of Zoology, Ahead of Print. In the wild, vertebrates face numerous unpredictable and harmful stressors such as storms, fires, earthquakes, tsunamis, and others. A typical physiological response to a perceived stressor is the increased secretion of glucocorticoids. Such a response is adaptive in the short term and could modulate the cellular immune response. Our purpose in this study was to examine the effect of stimulation with adrenocorticotropin (ACTH) injection and physical restraint (PR) on plasma corticosterone (CORT) levels, and total and differential white blood cell counts in the Broad-snouted Caim...
Source: Canadian Journal of Zoology - August 25, 2022 Category: Zoology Authors: Mar ía Soledad Moleón Pablo Fernando Cuervo Mar ía Virginia Parachú Marcó Elisa Olivia Pietrobon Graciela Alma Jahn Pablo Ariel Siroski Source Type: research
Co-roosting within an enclosed space: are Chimney Swifts (Chaetura pelagica) disturbed by sharing a roost chimney with Rock Pigeons (Columba livia)
We report co-roosting of Chimney Swifts (Chaetura pelagica (Linnaeus, 1758)) and Rock Pigeons (Columba livia J.F. Gmelin, 1789) in a Sault Ste Marie, Ontario, Canada, chimney. We predicted that life history and behavioural differences between the two species would lead to disturbance in Chimney Swifts, but not Pigeons. Of two chimneys examined, Swifts exited earlier in the morning in the chimney with co-roosting than in the chimney where they roosted alone. While Pigeons appeared undisturbed by moving Swifts unless Swifts landed on them, Swifts were sensitive to Pigeon activity. In the evening, Pigeon movements caused Swif...
Source: Canadian Journal of Zoology - August 25, 2022 Category: Zoology Authors: Jennie Pearce Jennifer Foote Source Type: research
Habitat preferences of young-of-year spotted gar (Lepisosteus oculatus) in Rondeau Bay, Lake Erie
Canadian Journal of Zoology, Ahead of Print. The young-of-year (YOY) habitat of many fishes listed under the Species at Risk Act (SARA) is poorly described, yet identifying critical habitat is essential to ensure species recovery. Past research on the Endangered spotted gar (Lepisosteus oculatus Winchell, 1864) in Canada has focused on the habitat use of adults and juveniles, but little is known about the occurrence and habitat use of YOY. Dip net and aquatic habitat sampling were performed in nearshore (lakefront, agricultural drain), mid-channel (agricultural drain), and offshore sites within Rondeau Bay to determine the...
Source: Canadian Journal of Zoology - August 22, 2022 Category: Zoology Authors: Keith McAllister D. Andrew R. Drake Michael Power Source Type: research
Strategy of spawning in the tropical squid Lolliguncula diomedeae females: allocation of energy, senescence, and influence of Aggregata coccidians
Canadian Journal of Zoology, Ahead of Print. Although the squid Lolliguncula diomedeae (Hoyle, 1904) is of commercial and ecological importance in the Gulf of Tehuantepec (southeastern Mexico), this is the first study to examine female spawning strategy. Information on reproductive indicators was used to assess the impact of spawning behavior on growth rates and the condition of somatic tissue, since energy for reproduction is derived mainly from somatic tissue and consumed food. Additionally, oocyte storage patterns were examined to determine the type of spawning that characterizes this species. A total of 1347 females, r...
Source: Canadian Journal of Zoology - August 19, 2022 Category: Zoology Authors: Mar ía del Carmen Alejo-Plata Miguel del Rio Portilla Adri án F. González-Acosta Sairi Sarai Le ón Guzmán Source Type: research
Nest defense by Mountain Bluebirds (Sialia currucoides) is related to their sex and brood characteristics but not morphological attributes
Canadian Journal of Zoology, Ahead of Print. Within species, bird parents defend their nests with different levels of intensity. Previous studies have examined several hypotheses for this variation by looking at factors such as morphological characteristics of the parents and the characteristics of the brood, but few have controlled for multiple factors simultaneously. Here we examined a broad range of factors that may influence the nest defense behaviour of Mountain Bluebirds (Sialia currucoides (Bechstein, 1798)), including the adult's morphology (sex, age, plumage colour, body size, and body condition) and characteristi...
Source: Canadian Journal of Zoology - August 18, 2022 Category: Zoology Authors: Simon P. Tkaczyk Douglas P. Chivers Karen L. Wiebe Source Type: research
Body size of raccoons (Procyon lotor) introduced in west-central Hokkaido, Japan: evaluation using two spatial scales
In this study, we evaluated the body size of adult raccoons (Procyon lotor (Linnaeus, 1758)) inhabiting Hokkaido, Japan, by comparing populations from different latitudes. Second, we examined the contribution of anthropogenic food (i.e., residential areas, crop field areas, and livestock farm density) to variations in body size in our study area in west-central Hokkaido. Using body mass as an index of body size, we found that body size did not change along latitudinal clines. Thus, the body mass of omnivorous carnivores may be unaffected by climatic variations. On a regional scale, anthropogenic food did not affect the bod...
Source: Canadian Journal of Zoology - August 17, 2022 Category: Zoology Authors: Saya Yamaguchi Mayumi Ueno Source Type: research
Prehistoric perspectives can help interpret the present: 14 000 years of moose (Alces alces) in the Western Arctic
Canadian Journal of Zoology, Ahead of Print. Rapidly changing climate at high latitudes has triggered a search for bellwethers of ecological change there. If the initial signs of change can be identified, perhaps we can predict where these changes will lead. Large-bodied, terrestrial herbivores are potential candidates for bellwether taxa because of the key roles they play in some ecological communities. Here, we assembled historical, archaeological, and paleontological records of moose (Alces alces (Linnaeus, 1758)) from the western Arctic and subarctic. The results showed that rather than having recently invaded tundra r...
Source: Canadian Journal of Zoology - August 11, 2022 Category: Zoology Authors: P. Groves D.H. Mann M.L. Kunz Source Type: research
Migratory connectivity and timing for an at-risk Canadian landbird, Eastern Whip-poor-will (Antrostomus vociferus), from two geographically distant breeding areas
Canadian Journal of Zoology, Ahead of Print. Determining the year-round spatial distributions of at-risk avian migratory species is critical for effective conservation. High-precision tracking enables the identification of distant breeding and nonbreeding areas and their connectivity, as well as migratory routes and associated threats. We GPS-tracked two groups of Eastern Whip-poor-wills (Antrostomus vociferus (A. Wilson, 1812)) that breed near the northern edge of their range, in Manitoba and northwestern Ontario ( “west”), and in southern Ontario (“east”), Canada. The western-breeding birds were also ∼5° of la...
Source: Canadian Journal of Zoology - August 8, 2022 Category: Zoology Authors: Alicia M. Korpach Christina M. Davy Alex Mills Kevin C. Fraser Source Type: research
