Diet reveals potential for competition and coexistence among coyotes (Canis latrans), red foxes (Vulpes vulpes), and gray foxes (Urocyon cinereoargenteus)
Canadian Journal of Zoology, Ahead of Print. Species can alleviate competition by reducing diet overlap. Non-native coyotes (Canis latrans Say, 1823) and historically native gray foxes (Urocyon cinereoargenteus (Schreber, 1775)) have expanded their ranges and may compete with native red foxes (Vulpes vulpes (Linnaeus, 1758)). To examine potential competition among canids in Maine, USA, we compared δ13C and δ15N from muscle and hair samples to assess relative resource use, and we compared frequency of occurrence of prey items from stomach contents to assess diets. For these species, red foxes consumed anthropogenically ba...
Source: Canadian Journal of Zoology - November 23, 2021 Category: Zoology Authors: Henry M. Masters Christine R. Maher Source Type: research
Comparing the population structure of the specialist Butler ’s Gartersnake (Thamnophis butleri) and the generalist Eastern Gartersnake (Thamnophis sirtalis sirtalis) in Ontario (Canada) and Michigan (USA)
Canadian Journal of Zoology, Ahead of Print. Species differing in life-history attributes vary in their responses to features within a shared landscape. We evaluated genetic structure of sympatric gartersnake species in southwestern Ontario (Canada) and southeastern Michigan (USA), where habitat fragmentation is high due to agriculture and urbanization. We surveyed genetic structure of a habitat specialist, Butler ’s Gartersnake (Thamnophis butleri (Cope, 1889)), and a habitat generalist, Eastern Gartersnake (Thamnophis sirtalis sirtalis (Linnaeus, 1758)), using DNA microsatellites. Bayesian clustering, discriminant analys...
Source: Canadian Journal of Zoology - November 15, 2021 Category: Zoology Authors: Megan Snetsinger Jeffrey R. Row Megan E. Hazell Dennis Plain Stephen C. Lougheed Source Type: research
Comparing the population structure of the specialist Butler ’s Gartersnake (Thamnophis butleri) and the generalist Eastern Gartersnake (Thamnophis sirtalis sirtalis) in Ontario (Canada) and Michigan (USA)
Canadian Journal of Zoology, Ahead of Print. Species differing in life-history attributes vary in their responses to features within a shared landscape. We evaluated genetic structure of sympatric gartersnake species in southwestern Ontario (Canada) and southeastern Michigan (USA), where habitat fragmentation is high due to agriculture and urbanization. We surveyed genetic structure of a habitat specialist, Butler ’s Gartersnake (Thamnophis butleri (Cope, 1889)), and a habitat generalist, Eastern Gartersnake (Thamnophis sirtalis sirtalis (Linnaeus, 1758)), using DNA microsatellites. Bayesian clustering, discriminant anal...
Source: Canadian Journal of Zoology - November 15, 2021 Category: Zoology Authors: Megan Snetsinger Jeffrey R. Row Megan E. Hazell Dennis Plain Stephen C. Lougheed Source Type: research
Avian eggshell coloration predicts shell-matrix protoporphyrin content
Canadian Journal of Zoology, Ahead of Print. Avian eggshell pigmentation may provide information about a female ’s physiological condition, in particular her state of oxidative balance. Previously we found that female House Wrens (Troglodytes aedon Vieillot, 1809) with lighter, less-maculated, and redder ground-colored shells were older and produced heavier offspring than females laying more-maculated and b rowner eggs. The strong pro-oxidant protoporphyrin is responsible for this species’ eggshell pigmentation, so differences in pigmentary coloration may be related to eggshell protoporphyrin content and reflect female...
Source: Canadian Journal of Zoology - November 12, 2021 Category: Zoology Authors: Charles F. Thompson Kara E. Hodges Nathan T. Mortimer Alysia D. Vrailas-Mortimer Scott K. Sakaluk Mark E. Hauber Source Type: research
Wing plastic response to temperature variation in two distantly related Neotropical Drosophila species (Diptera, Drosophilidae)
Canadian Journal of Zoology, Ahead of Print. Phenotypic plasticity has been described for morphological and life-history traits in many organisms. In Drosophila, temperature drives phenotypic change in several traits, but few Neotropical species have been studied and whether the phenotypic variation associated with plasticity is adaptive remains unclear. Here, we studied the phenotypic response to temperature variation in the distantly related Neotropical species Drosophila mercatorum Patterson and Wheeler, 1942 and Drosophila willistoni Sturtevant, 1916. We evaluate if wing shape variation follows that observed in the Neo...
Source: Canadian Journal of Zoology - November 11, 2021 Category: Zoology Authors: Waira S. Machida Rosana Tidon Julia Klaczko Source Type: research
Rapid advancement of spring migration and en route adjustment of migration timing in response to weather during fall migration in Vaux’s Swifts (Chaetura vauxi)
Canadian Journal of Zoology,Volume 100, Issue 1, Page 56-63, January 2022. Climate change has generated earlier springs, later falls, and different weather patterns. These changes may prove challenging to migratory species if they are unable to adjust their migratory timing. We analyzed changes in migratory timing of Vaux ’s Swifts (Chaetura vauxi (J.K. Townsend, 1839)) by examining first arrivals (date the first swift arrived) and peak roost occupancy (date the maximum number of swifts were observed) at migratory roosts in both spring and fall from the citizen science organization Vaux’s Happening. First arrival s and pea...
Source: Canadian Journal of Zoology - November 9, 2021 Category: Zoology Authors: E.D. Prytula A.E. McKellar L. Schwitters M.W. Reudink Source Type: research
Rapid advancement of spring migration and en  route adjustment of migration timing in response to weather during fall migration in Vaux’s Swifts (Chaetura vauxi)
Canadian Journal of Zoology, Ahead of Print. Climate change has generated earlier springs, later falls, and different weather patterns. These changes may prove challenging to migratory species if they are unable to adjust their migratory timing. We analyzed changes in migratory timing of Vaux ’s Swifts (Chaetura vauxi (J.K. Townsend, 1839)) by examining first arrivals (date the first swift arrived) and peak roost occupancy (date the maximum number of swifts were observed) at migratory roosts in both spring and fall from the citizen science organization Vaux’s Happening. First arrival s and peak occupancy date in Vauxâ€...
Source: Canadian Journal of Zoology - November 9, 2021 Category: Zoology Authors: E.D. Prytula A.E. McKellar L. Schwitters M.W. Reudink Source Type: research
Intraspecific structure of the Coregonus lavaretus complex in water bodies of Siberia: a case of postglacial allopatric origin of Yukagirian whitefish
Canadian Journal of Zoology, Ahead of Print. The results of morphological and genetic analyses of forms/species of the Coregonus lavaretus pidschian (Gmelin, 1789) complex from the Indigirka and Kolyma river basins are presented in the context of there being recent postglacial speciation events. It has been found that the studied whitefishes belong to the sparsely rakered and low lateral-line forms and have previously been described as Coregonus lavaretus pidschian n. Â jucagiricus Drjagin (Berg), 1932. Based on these characters, this whitefish does not differ from most Arctic whitefish populations (in particular from Core...
Source: Canadian Journal of Zoology - November 5, 2021 Category: Zoology Authors: Nickolai A. Bochkarev Elena I. Zuykova Lyudmila A. Pestryakova Lena A. Ushnitskaya Evgeny S. Zakharov Dmitry V. Politov Karl B. Andree Mikhail M. Solovyev Source Type: research
Evidence of dispersal between the Yenisei and the Lena river basins during the late Pleistocene within the whitefish (Coregonus lavaretus pidschian) complex
Canadian Journal of Zoology, Ahead of Print. The Coregonus lavaretus (Linnaeus, 1758) complex is a morphologically and genetically diverse group of whitefish. Its taxonomic structure has been controversial for almost a century. At least 25 forms of C. lavaretus have been described in Siberia, but there is still no consensus on their intraspecific structure and taxonomy. Coregonus lavaretus pidschian (Gmelin, 1789) was described as a subspecies of C. lavaretus. Recently, it was assumed that this subspecies is also a complex. The purpose of this study was to compare the distributions of pidschian-like whitefish haplotypes in...
Source: Canadian Journal of Zoology - November 5, 2021 Category: Zoology Authors: Nickolay A. Bochkarev Elena I. Zuykova Alexey V. Katokhin Karl B. Andree Mikhail M. Solovyev Source Type: research
Investigating factors that set the lower elevational limit of Canada Jays (Perisoreus canadensis) on Vancouver Island, British Columbia, Canada
Canadian Journal of Zoology, Ahead of Print. The biotic and abiotic factors responsible for determining ranges of most species are poorly understood. The Canada Jay (Perisoreus canadensis (Linnaeus, 1766)) relies on perishable cached food for over-winter survival and late-winter breeding and the persistence of cached food could be a driver of range limits. We confirmed that the Canada Jay ’s lower elevational limit on Vancouver Island, British Columbia, Canada, matches that of the subalpine zone (900 m) and then conducted simulated caching experiments to examine the influence of antimicrobial properties of subalpine tre...
Source: Canadian Journal of Zoology - November 4, 2021 Category: Zoology Authors: Nathaniel J. Quarrell Dan Strickland D. Ryan Norris Source Type: research
Estimating abundance, temporary emigration, and the pattern of density dependence in a cyclic snowshoe hare (Lepus americanus) population in Yukon, Canada
Canadian Journal of Zoology, Ahead of Print. Estimates of demographic parameters based on capture –mark–recapture (CMR) methods may be biased when some individuals in the population are temporarily unavailable for capture (temporary emigration). We estimated snowshoe hare abundance, apparent survival, and probability of temporary emigration in a population of snowshoe hares (Lepus americanus Erxleben, 1777) in the Yukon (Canada) using Pollock’s robust design CMR model, and population density using spatially explicit CMR models. Survival rates strongly varied among cyclic phases, seasons, and across five population cy...
Source: Canadian Journal of Zoology - October 27, 2021 Category: Zoology Authors: Madan K. Oli Alice J. Kenney Rudy Boonstra Stan Boutin Vratika Chaudhary James E. Hines Charles J. Krebs Source Type: research
Physiological parameters of a plover during nonbreeding and breeding seasons in Patagonia, Argentina
Canadian Journal of Zoology, Ahead of Print. Migratory shorebirds are the most threatened avian species due to the effects of human activities and climate change. Physiological parameters are useful to evaluate the health status of free-living animals. Here we investigated lymphocytes, heterophils, heterophils/lymphocytes, and glucose for female and male Two-banded Plovers (Charadrius falklandicus Latham, 1790) during nonbreeding (body moult) and breeding (incubation) seasons in coastal areas of northern Patagonia, Argentina. We also measured corticosterone for the first time for this species during the breeding season. No...
Source: Canadian Journal of Zoology - October 27, 2021 Category: Zoology Authors: Ver ónica L. D’Amico Glenda D. Hevia Brian Walker Patricia M. Gonz ález Marcelo Bertellotti Source Type: research
Signals from predators, injured conspecifics, and pesticide modify the swimming behavior of the gregarious tadpole of the Dorbigny ’s Toad, Rhinella dorbignyi (Anura: Bufonidae)
This study evaluated the swimming activity of Dorbigny ’s Toad (Rhinella dorbignyi (Duméril and Bibron, 1841)) tadpoles exposed to chemical signals, including cues from a predator fish, the marbled swamp eel (Synbranchus marmoratus Bloch, 1795), and an injured conspecific; sublethal concentration of insecticide cypermethrin; and their combination. Sw imming behavior (total distance moved, mean speed, global activity, number of contacts between tadpoles) was evaluated in an individual (1) and groups of different size (3, 5, 7, and 10 tadpoles) using a video-tracking software tool. Predator exposure modified behavioral p...
Source: Canadian Journal of Zoology - October 27, 2021 Category: Zoology Authors: L.M. Curi A.P. Cuzziol Boccioni P.M. Peltzer A.M. Attademo A. Bass ó E.J. Le ón R.C. Lajmanovich Source Type: research
Habitat occupancy by Spruce Grouse (Canachites canadensis) in the south of its range in Quebec, Canada
Canadian Journal of Zoology, Ahead of Print. Studying habitat occupancy at the margins of the distributions of species can be helpful in clarifying the requirements of species and planning management measures. Spruce Grouse (Canachites canadensis (Linnaeus, 1758)), a bird species associated with northern short-needle coniferous forests in North America, has its southeastern range limit where coniferous forests are mixed with temperate deciduous forests and agricultural lands. Some isolated populations are found in these habitats. Using a single-season occupancy modelling approach, we investigated habitat use by Spruce Grou...
Source: Canadian Journal of Zoology - October 26, 2021 Category: Zoology Authors: Clara Casabona i Amat Pierre Blanchette Andr é Desrochers Source Type: research
Sexual dimorphism in the parasitic snail Nanobalcis worsfoldi: a histological and morphometric approach with insights for the family Eulimidae
Canadian Journal of Zoology, Ahead of Print. Sexual dimorphism has long been stressed as a remarkable characteristic of Eulimidae snails. This idea is so common for this family that, even without information on the soft parts, some species were already identified as male or female, as observed in Nanobalcis worsfoldi War én, 1990. Here, we investigated whether larger and smaller individuals of N. worsfoldi are female and male, respectively, and what are the most useful characteristics to differentiate the sexes. We analyzed shell morphology and morphometry, along with coloration of the soft parts of large and small indivi...
Source: Canadian Journal of Zoology - October 23, 2021 Category: Zoology Authors: Licia Sales Vinicius Queiroz Source Type: research
