The effect of a single prerelease exposure to conspecific alarm cue on poststocking survival in three strains of rainbow trout (Oncorhynchus mykiss)
Canadian Journal of Zoology, e-First Articles. Significant resources go toward rearing and stocking fish globally, yet poststocking survival is often low, largely due to high predation rates on hatchery-reared fish. Antipredator behavior has been enhanced in many species through exposure to chemical cues that simulate predation events, but the implementation of such protocols may be logistically challenging. It has been suggested that a single exposure of hatchery fish to chemical cues while en route to stocking locations may be sufficient to enhance antipredator behavior and improve survival. We tested whether a one-time ...
Source: Canadian Journal of Zoology - July 28, 2016 Category: Zoology Authors: Christopher J. Kopack E. Dale Broder Eric R. Fetherman Jesse M. Lepak Lisa M. Angeloni Source Type: research

The short-term impact of abundant fruit upon deer mouse (Peromyscus maniculatus), southern red-backed vole (Myodes gapperi), and woodland jumping mouse (Napaeozapus insignis) populations
Canadian Journal of Zoology, e-First Articles. Fruit has been identified as an important and potentially population-restricting food for southern red-backed voles (Myodes gapperi (Vigors, 1830)), deer mice (Peromyscus maniculatus (Wagner, 1845)), and woodland jumping mice (Napaeozapus insignis (Miller, 1891)). We added domestic dried strawberries (Fragaria × ananassa (Weston) Duchesne ex Rozier (pro sp.)) and European black currants (Ribes nigrum L.), which have native analogues and are preferred foods of these rodents, to white spruce (Picea glauca (Moench) Voss) plantations from May through August 2011 and 2012 to...
Source: Canadian Journal of Zoology - July 28, 2016 Category: Zoology Authors: Evan C. Dracup Daniel M. Keppie Graham J. Forbes Source Type: research

Rocky Mountain bighorn sheep (Ovis canadensis canadensis) winter habitat selection and seasonal movements in an area of active coal mining
We examined winter habitat selection by Rocky Mountain bighorn sheep (Ovis canadensis canadensis Shaw, 1804) where four large, open-pit coal mines are in operation. Sheep in this area generally winter at high elevation on windswept, south-facing native grasslands. We used GPS collars and Resource Selection Function analysis to examine movements and habitat selection. A majority (79%) of the sheep were migratory and fidelity to winter ranges was high (88%). Sheep showed low use ( ∼10%–20%) of mine areas between November and April, followed by increased use peaking at 60%–65% in September–October. Winte...
Source: Canadian Journal of Zoology - July 21, 2016 Category: Zoology Authors: Kim G. Poole Rob Serrouya Irene E. Teske Kevin Podrasky Source Type: research

Differential growth of body segments explains ontogenetic shifts in organ position for the Diamondback Water Snake (Nerodia rhombifer)
Canadian Journal of Zoology,Volume 94, Issue 9, Page 651-660, September 2016. As snakes grow, their organs move anteriorly relative to body size. We explored a developmental explanation for the ontogenetic shift in the relative position of internal organs for snakes using the Diamondback Water Snake (Nerodia rhombifer (Hallowell, 1852)). With age, this water snake ’s heart, liver, small intestine, and right kidney move anteriorly by 2.5–5.0 percentage points of snout–vent length. The number of precaudal vertebrae did not vary due to size or sex. The anterior edge of the heart, liver, small intestine, and ...
Source: Canadian Journal of Zoology - July 12, 2016 Category: Zoology Authors: G.E. Anderson S.M. Secor Source Type: research

Tree Swallow (Tachycineta bicolor) foraging responses to agricultural land use and abundance of insect prey
Canadian Journal of Zoology,Volume 94, Issue 9, Page 637-642, September 2016. Throughout North America, many species of aerial insectivorous birds have exhibited steep declines. The timing of these declines coincides with changes in agriculture, perhaps signaling a causal link. Increased agrochemical use, wetland drainage, and cropping intensity may indirectly influence insectivores by reducing the abundance of insect prey. Our objective was to determine whether changes in insect abundance and biomass on agricultural landscapes in the Canadian Prairies influence the foraging behaviour of breeding Tree Swallows (Tachycineta...
Source: Canadian Journal of Zoology - June 22, 2016 Category: Zoology Authors: R.L. Stanton C.A. Morrissey R.G. Clark Source Type: research

Size-dependent predation alters interactions between parasites and predators
Canadian Journal of Zoology, e-First Articles. Increasing evidence indicates that parasites play an important role within many systems as prey for higher trophic levels. Predation on parasites can decrease their numbers and may affect host infection rates. Cercariae, a free-living infectious stage of trematode parasites, are abundant in freshwater systems and are directly consumed by a number of freshwater predators. However, few studies have tested whether predators exhibit a preference for cercariae when alternative prey are available or how these preferences vary across predator body sizes. We assessed whether dragonfly...
Source: Canadian Journal of Zoology - June 17, 2016 Category: Zoology Authors: S.V.L. Catania J. Koprivnikar S.J. McCauley Source Type: research

Intestinal parasites of gray wolves (Canis lupus) in northern and western Canada
We examined 191 intestines from wolves harvested for other purposes from regions in the Northwest Territories, Br itish Columbia, Saskatchewan, and Manitoba. Adult helminths were collected from intestinal contents for morphological and molecular identification, and for a subset of wolves, fecal samples were also analyzed to detect helminth eggs and protozoan (oo)cysts. Using both detection methods, we found tha t 83% of 191 intestines contained one or more parasite species, including cestodes (Taenia spp., Echinococcus spp., and Diphyllobothrium sp.), nematodes (Uncinaria stenocephala Railliet, 1884, Trichuris spp., Physal...
Source: Canadian Journal of Zoology - June 15, 2016 Category: Zoology Authors: Janna M. Schurer Michael Pawlik Anna Huber Brett Elkin H. Dean Cluff Jodie D. Pongracz Karen Gesy Brent Wagner Brent Dixon Harriet Merks Mandeep S. Bal Emily J. Jenkins Source Type: research

Fluctuating versus constant temperatures: effects on metabolic rate and oxidative damages in freshwater crustacean embryos
Canadian Journal of Zoology, e-First Articles. Rising temperatures will pose a major threat, notably for freshwater ecosystems, in the decades to come. Temperature, a major environmental factor, affects organisms ’ physiology and metabolism. Most studies of temperature effect address constant thermal regime (CTR), whereas organisms are exposed to fluctuating thermal regime (FTR) in their natural environments. In addition, previous works have predominantly addressed issues of thermal tolerance in adults rat her than in early life stages. Therefore, for the first time to our knowledge, we aimed to investigate the influ...
Source: Canadian Journal of Zoology - June 13, 2016 Category: Zoology Authors: Natacha Foucreau Charly Jehan Martin Lawniczak Fr édéric Hervant Source Type: research

Muscle protection during hibernation of Daurian ground squirrels (Spermophilus dauricus): role of atrogin-1, MuRF1, and fiber-type transition
Canadian Journal of Zoology, e-First Articles. We investigated the mechanism of protection from skeletal muscle atrophy in the hind limb extensor digitorum longus (EDL) muscle of hibernating Daurian ground squirrels (Spermophilus dauricus Brandt, 1843). The effects of unrestrained hibernation and 14 day hind limb unloading (HLU) on EDL were studied in three seasons (summer, autumn, and winter). Atrogin-1 and MuRF1 mRNA skeletal muscle expression, wet muscle mass, and muscle to body mass ratios were unchanged during hibernation in all three seasons. EDL mass measurements decreased following HLU and atrogin-1 and MuRF1 mRNA ...
Source: Canadian Journal of Zoology - June 8, 2016 Category: Zoology Authors: Kai Dang Ban Feng Yunfang Gao Naifei Hu Shanfeng Jiang Weiwei Fu Helmut G. Hinghofer-Szalkay Source Type: research

Variation in the intensity and prevalence of macroparasites in migratory caribou: a quasi-circumpolar study
Canadian Journal of Zoology, e-First Articles. Comparative studies across time and geographical regions are useful to improve our understanding of the health of wildlife populations. Our goal was to study parasitism in migratory caribou (Rangifer tarandus (L., 1758)) of North America and Greenland. A total of 1507 caribou were sampled across 12 herds to assess seven of their main helminth and arthropod macroparasites between 1978 and 2010. We sought to determine which factors such as sex, age class, herd size, and season best explained the prevalence and intensity of those parasites. Intensity of warble fly (Hypoderma tara...
Source: Canadian Journal of Zoology - June 8, 2016 Category: Zoology Authors: Alice-Anne Simard Susan Kutz Julie Ducrocq Kimberlee Beckmen Vincent Brodeur Mitch Campbell Bruno Croft Christine Cuyler Tracy Davison Brett Elkin Tina Giroux Allicia Kelly Don Russell Jo ëlle Taillon Alasdair Veitch Steeve D. C ôté Source Type: research

Temperature-independent, seasonal fluctuations in immune function of the Mojave Desert Tortoise (Gopherus agassizii)
Canadian Journal of Zoology, e-First Articles. As long-lived reptiles, Mojave Desert Tortoises (Gopherus agassizii (Cooper, 1861)) are expected to make substantial energetic investments in immune defense. This species also has many adaptations to living in an arid environment characterized by seasonal extremes in temperature and resource availability. By housing G. agassizii at a controlled, constant ambient temperature, we quantified predominantly temperature-independent, seasonal fluctuations in innate immune function and circulating leukocytes in a reptile. We found a decrease in bacteriocidal activity of the blood plas...
Source: Canadian Journal of Zoology - June 8, 2016 Category: Zoology Authors: F.C. Sandmeier K.R. Horn C.R. Tracy Source Type: research

First estimates of the probability of survival in a small-bodied, high-elevation frog (Boreal Chorus Frog, Pseudacris maculata), or how historical data can be useful
Canadian Journal of Zoology, e-First Articles. In an era of shrinking budgets yet increasing demands for conservation, the value of existing (i.e., historical) data are elevated. Lengthy time series on common, or previously common, species are particularly valuable and may be available only through the use of historical information. We provide first estimates of the probability of survival and longevity (0.67 –0.79 and 5–7 years, respectively) for a subalpine population of a small-bodied, ostensibly common amphibian, the Boreal Chorus Frog (Pseudacris maculata (Agassiz, 1850)), using historical data and contemp...
Source: Canadian Journal of Zoology - June 7, 2016 Category: Zoology Authors: E. Muths R.D. Scherer S.M. Amburgey T. Matthews A.W. Spencer P.S. Corn Source Type: research

Timing of nesting of upland-nesting ducks in the Canadian prairies and its relation to spring wetland conditions
Canadian Journal of Zoology, e-First Articles. Timing of breeding varies among waterfowl species and individuals, with strong effects on reproductive success, and may be related to habitat quality. Here, we analyse the start, span, and end of the nesting season for nine upland-nesting duck species at 166 Canadian Prairie –Parkland sites over 34 years to better characterize nesting patterns and test whether and how species respond to May pond abundances. Nesting metrics were compared between single-site versus multiple-site studies over 7 years to evaluate the effects of spatial scale and methodology. Strong, consi st...
Source: Canadian Journal of Zoology - June 2, 2016 Category: Zoology Authors: A.J. Raquel J.H. Devries D.W. Howerter R.T. Alisauskas S.W. Leach R.G. Clark Source Type: research

Stress level, parasite load, and movement pattern in a small-mammal reservoir host for Lyme disease
Canadian Journal of Zoology, e-First Articles. Occurrence of Lyme disease has increased rapidly in Canada in the past 5 years. The emergence of Lyme disease coincides with the range expansion of the primary host, the white-footed mouse (Peromyscus leucopus (Rafinesque, 1818)), in the region. We evaluated the effects of stress level, parasite load, and forest-patch characteristics on P. leucopus movement pattern. We found negative relations between on the one hand the adrenal gland size, a proxy for stress level, and population density, and on the other hand, home-range area and movement rate of mouse individuals, suggestin...
Source: Canadian Journal of Zoology - May 31, 2016 Category: Zoology Authors: J. Gaitan V. Millien Source Type: research

Harbor porpoise (Phocoena phocoena) recovery in the inland waters of Washington: estimates of density and abundance from aerial surveys, 2013–2015
Canadian Journal of Zoology, Volume 94, Issue 7, Page 505-515, July 2016. The harbor porpoise (Phocoena phocoena (L., 1758)) used to be common in Puget Sound, Washington, but virtually disappeared from these waters by the 1970s. We conducted systematic aerial line-transect surveys (17 237 km total effort) for harbor porpoises, with the goal of estimating density and abundance in the inland waters of Washington State. Surveys in Puget Sound occurred throughout the year from 2013 to 2015, and in the Strait of Juan de Fuca and the San Juan Islands (and some adjacent Canadian waters) in April 2015. We used a high-wing, ...
Source: Canadian Journal of Zoology - May 27, 2016 Category: Zoology Authors: Thomas A. JeffersonMari A. SmulteaSarah S. CourbisGregory S. Campbell Source Type: research

Neuronal diversity and their spine density in the hippocampal complex of the House Crow (Corvus splendens), a food-storing bird
Canadian Journal of Zoology, e-First Articles. Hippocampus, one of the parts included in the limbic system, is involved in various functions such as learning, memory, food-storing behavior, and sexual discrimination. Neuronal classes of the hippocampal complex in food-storing birds have been also reported, but the study lacks details pertaining to neuronal characteristics and the spine density of the neurons in different subfields of the hippocampus. Hence, the present study was undertaken with the aim to explore the morphology of neurons and the spines present on their dendrites within the hippocampal complex of the Hous...
Source: Canadian Journal of Zoology - May 26, 2016 Category: Zoology Authors: U.C. Srivastava Durgesh Singh Prashant Kumar Sippy Singh Source Type: research

Trophic biology and migratory patterns of sympatric Dolly Varden (Salvelinus malma) and Arctic char (Salvelinus alpinus)
Canadian Journal of Zoology, e-First Articles. The trophic ecology (diet and head morphology) and migration patterns of two closely related salmonid fishes, Arctic char (Salvelinus alpinus (L., 1758)) and Dolly Varden (Salvelinus malma (Walbaum, 1792)), were examined in tributaries of Lake Aleknagik, southwestern Alaska, to test for differentiation between species. Schoener’s index of proportional overlap and multivariate analyses of diets suggested that these species had significantly different trophic niches. Arctic char and the largest individuals of both species had the most diverse diets, and sockeye salmon (Onc...
Source: Canadian Journal of Zoology - May 26, 2016 Category: Zoology Authors: A.M. DennertS.L. May-McNallyM.H. BondT.P. QuinnE.B. Taylor Source Type: research

Characterizing phenotypic divergence using three-dimensional geometric morphometrics in four populations of threespine stickleback (Gasterosteus aculeatus; Pisces: Gasterosteidae) in Katmai National Park and Preserve, Alaska
We report significant phenotypic differences among all four populations that includes a component of sexual dimorphism. Furthermore, we show evidence of disrupted phenotypic covariance structure among these populations. Taken together, these findings indicate the importance of phenotypic quantification as a key step in elucidating both the ecological processes responsible for rapid adaptive radiations and the role of developmental mechanisms in biasing evolutionary change. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - May 21, 2016 Category: Zoology Authors: A.E. PistoreT.N. BarryE. BowlesR. SharmaS.L. VanderzwanS.M. RogersH.A. Jamniczky Source Type: research

Testing for a predicted decrease in body size in brown bears (Ursus arctos) based on a historical shift in diet
Canadian Journal of Zoology, Volume 94, Issue 7, Page 489-495, July 2016. A recent study found a historical decline in the proportion of meat in the diet of brown bears (Ursus arctos L., 1758) in the Hokkaido Islands, Japan. Because feeding habits are strongly correlated with the body size of animals, the shift in diet should have led to a decrease in the size of these bears. To predict the effects of this dietary shift on the skeletal size in bears, we correlated the femur length in Hokkaido brown bears with the carbon and nitrogen stable isotope values from bone samples and predicted the historical change in their body s...
Source: Canadian Journal of Zoology - May 14, 2016 Category: Zoology Authors: Jun MatsubayashiIchiro TayasuJunko O. MorimotoTsutomu Mano Source Type: research

Amphibian habitat creation on postindustrial landscapes: a case study in a reclaimed coal strip-mine area
Canadian Journal of Zoology, e-First Articles. Although habitat loss is a major driver of amphibian and reptile declines globally, a subset of postindustrial landscapes, reclaimed and restored, are creating habitat for these animals in the United States. In southwestern Indiana, along the southeastern edge of the Illinois Coal Basin, post-SMCRA (Surface Mining Control and Reclamation Act of 1977) grassland restorations are recreating prairies in a region where they occurred naturally as openings (pockets) in deciduous forest, but were destroyed by agricultural activities following Euro-American settlement. Furthermore, it ...
Source: Canadian Journal of Zoology - May 13, 2016 Category: Zoology Authors: Rochelle M. Stiles Jonathan W. Swan Jaimie L. Klemish Michael J. Lannoo Source Type: research

Nest defense and parental investment in Song Sparrows (Melospiza melodia)
Canadian Journal of Zoology, Volume 94, Issue 7, Page 473-477, July 2016. Individual variation in nest defense behaviour is common in altricial birds, but despite clear predictions about why such variation exists, there is no consensus on its causes. We tested for an influence of five predictors of individual variation in nest defense behaviour, including time of season, offspring age, parental age and sex, and clutch size in a well-studied Song Sparrow (Melospiza melodia (A. Wilson, 1810)) population. We recorded parental responses to a standardized human approach and used model selection to assess support for each predic...
Source: Canadian Journal of Zoology - May 13, 2016 Category: Zoology Authors: N. MorrellK.M. JohnsonC.E. TarwaterP. Arcese Source Type: research

North Atlantic humpback whale (Megaptera novaeangliae) hotspots defined by bathymetric features off western Puerto Rico
This study is especially important ahead of possible removal from the Endangered Species list. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - May 7, 2016 Category: Zoology Authors: M.M. MacKayB. WürsigC.E. BaconJ.D. Selwyn Source Type: research

Diurnal? Calling activity patterns reveal nocturnal habits in the aposematic toad Melanophryniscus rubriventris
Canadian Journal of Zoology, Volume 94, Issue 7, Page 497-503, July 2016. In diurnal species with short breeding seasons, an extension of diel activity to the night hours could be favoured to maximize mating opportunities, but individuals must deal with physiological and behavioural constraints. We tested this hypothesis in the Yungas Red-belly Toad (Melanophryniscus rubriventris (Vellard, 1947)). We registered the diel pattern of male calling activity in two localities using automated recording systems, and related it to abiotic factors such as temperature, relative air humidity, and precipitation. The diel pattern of voc...
Source: Canadian Journal of Zoology - May 7, 2016 Category: Zoology Authors: L.C. PereyraM.S. AkmentinsE.A. SanabriaM. Vaira Source Type: research

Structure and population dynamics of the secondary burrower crayfish Procambarus acanthophorus from a tropical Mexican wetland
Canadian Journal of Zoology, Volume 94, Issue 7, Page 479-488, July 2016. Catch size, sex ratio, structure and dynamics, as well as mortality, of a population of the secondary burrower crayfish Procambarus acanthophorus Villalobos, 1948, from tropical wetland La Mixtequilla, Veracruz, Mexico, were examined. Monthly samples were taken from artisanal commercial captures. A total of 2141 individuals were caught. Although the total female:male ratio was 0.86, variation in sex ratios have also been found in monthly catches. Monthly polymodal frequency distributions of cephalothorax length (CL) were analyzed by the Bhattacharya ...
Source: Canadian Journal of Zoology - April 22, 2016 Category: Zoology Authors: J.A. Viccon-PaleP. OrtegaL. Mendoza-VargasP. Castilla-HernándezA. López-CuevasA. Meléndez-HerradaF. Rivera-BecerrilG. Vela-CorreaM. Signoret-Poillon Source Type: research

Using climate, energy, and spatial-based hypotheses to interpret macroecological patterns of North America chelonians
Canadian Journal of Zoology, Volume 94, Issue 7, Page 453-461, July 2016. Our study investigates how factors, such as latitude, productivity, and several environmental variables, influence contemporary patterns of the species richness in North American turtles. In particular, we test several hypotheses explaining broad-scale species richness patterns on several species richness data sets: (i) total turtles, (ii) freshwater turtles only, (iii) aquatic turtles, (iv) terrestrial turtles only, (v) Emydidae, and (vi) Kinosternidae. In addition to spatial data, we used a combination of 25 abiotic variables in spatial regression ...
Source: Canadian Journal of Zoology - April 14, 2016 Category: Zoology Authors: Joshua R. EnnenMickey AghaWilfredo A. MatamorosSarah C. HazzardJeffrey E. Lovich Source Type: research

Challenges and advances in the study of pterosaur flight
Canadian Journal of Zoology, e-First Articles. Pterosaurs have fascinated scientists and nonscientists alike for over 200 years, as one of the three known clades of vertebrates to have evolved flapping flight. The smallest pterosaurs were comparable in size to the smallest extant birds and bats, but the largest pterosaurs were vastly larger than any extant flier. This immense size range, coupled with poor preservation and adaptations for flight unknown in extant vertebrates, have made interpretations of pterosaur flight problematic and often contentious. Here we review the anatomical, evolutionary, and phylogenetic h...
Source: Canadian Journal of Zoology - August 19, 2014 Category: Zoology Tags: article Source Type: research

Antipredator vigilance decreases with food density in staging flocks of Semipalmated Sandpipers (Calidris pusilla)
Canadian Journal of Zoology, e-First Articles. When animals face time constraints, antipredator vigilance is expected to decrease in patches with higher food density. Indeed, sacrifices in safety are worthwhile in rich food patches that allow substantial foraging gains in response to a decrease in vigilance. This prediction has received little empirical attention. I tested this prediction in fall-staging Semipalmated Sandpipers (Calidris pusilla (L., 1766)) using the frequency of looks while foraging as a proxy for vigilance. Fall-staging sandpipers face time constraints, as individuals must accumulate fat rapidly be...
Source: Canadian Journal of Zoology - August 13, 2014 Category: Zoology Tags: article Source Type: research

Seeds of doubt: feeding preferences of white-footed deer mice (Peromyscus leucopus noveboracensis) and woodland deer mice (Peromyscus maniculatus gracilis) on maple (genus Acer) seeds
This study explores foraging choices made by seed predators (white-footed mouse, Peromyscus leucopus noveboracensis (Fischer, 1829), and woodland deer mouse, Peromyscus maniculatus gracilis (LeConte, 1855)) presented with seeds of two dominant tree species (sugar maple, Acer saccharum Marsh., and red maple, Acer rubrum L.). I hypothesized that both species would prefer A. saccharum seeds, as they are larger and ostensibly contain more energy. Although P. l. noveboracensis consumed more seed than P. m. gracilis, there was also a species-specific difference in preference. Peromyscus maniculatus gracilis clearly preferred A. ...
Source: Canadian Journal of Zoology - August 12, 2014 Category: Zoology Tags: article Source Type: research

Cold tolerance performance of westslope cutthroat trout (Oncorhynchus clarkii lewisi) and rainbow trout (Oncorhynchus mykiss) and its potential role in influencing interspecific hybridization
Canadian Journal of Zoology, e-First Articles. Hybridization between rainbow trout (Oncorhynchus mykiss (Walbaum, 1792)) and westslope cutthroat trout (Oncorhynchus clarkii lewisi (Girard, 1856)) occurs commonly when rainbow trout are introduced into the range of westslope cutthroat trout. Typically, hybridization is most common in warmer, lower elevation habitats, but much less common in colder, higher elevation habitats. We assessed the tolerance to cold water temperature (i.e., critical thermal minimum, CTMin) in juvenile rainbow trout and westslope cutthroat trout to test the hypothesis that westslope cutthroat t...
Source: Canadian Journal of Zoology - July 28, 2014 Category: Zoology Tags: article Source Type: research

Habitat use by giant pandas (Ailuropoda melanoleuca) in relation to roads in the Wanglang Nature Reserve, People’s Republic of China
Canadian Journal of Zoology, e-First Articles. The impacts of roads on wildlife and their habitats have been widely recognized. To assess the effects of roads on habitat use of the giant panda (Ailuropoda melanoleuca (David, 1869)), we investigated the giant panda habitats and the roadside habitats in Wanglang Nature Reserve, People’s Republic of China. We found that giant pandas did not use the road-affected habitats, and compared with giant panda habitats, road-affected habitats were characterized by lower bamboo density and grazing disturbances. Therefore, our study demonstrated that roads negatively affecte...
Source: Canadian Journal of Zoology - July 17, 2014 Category: Zoology Tags: article Source Type: research

Modelling skin surface areas involved in water transfer in the Palmate Newt (Lissotriton helveticus)
Canadian Journal of Zoology, e-First Articles. Magnetic resonance imaging (MRI) based 3D reconstructions were used to derive accurate quantitative data on body volume and functional skin surface areas involved in water transfer in the Palmate Newt (Lissotriton helveticus (Razoumovsky, 1789)). Body surface area can be functionally divided into evaporative surface area that interacts with the atmosphere and controls the transepidermal evaporative water loss (TEWL); ventral surface area in contact with the substratum that controls transepidermal water absorption (TWA); and skin surface area in contact with other skin su...
Source: Canadian Journal of Zoology - July 16, 2014 Category: Zoology Tags: article Source Type: research

Diversity of early life-history traits in freshwater eels and the evolution of their oceanic migrations
Canadian Journal of Zoology, e-First Articles. Early life-history traits of all 19 anguillid eel species and subspecies were examined to help understand the evolutionary processes of their oceanic migrations in comparison with their migration distances and the geography of their species ranges. Tropical species were found to have fewer myomeres, greater body depths, higher growth rates, shorter larval durations, and smaller maximum larval sizes than temperate species. The relationships among larval characteristics such as growth rate, age at metamorphosis, and maximum larval size differed among tropical and temperate...
Source: Canadian Journal of Zoology - July 11, 2014 Category: Zoology Tags: article Source Type: research

Population, sex, and ontogenetic differences in the procurrent rays of the caudal fin in threespine sticklebacks (Gasterosteus aculeatus)
We examined D/V width ratios in 105 stained and cleared specimens from 13 additional allopatric lake populations on Haida Gwaii. Eight populations were symmetrical for width of dorsal and ventral rays, while three populations were ventrally biased and two populations were dorsally biased. D/V ratios were best predicted by positive associations with adult body size and negative associations with total number of gill rakers. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - July 8, 2014 Category: Zoology Tags: article Source Type: research

Anthropogenic food use and diet overlap between red foxes (Vulpes vulpes) and arctic foxes (Vulpes lagopus) in Prudhoe Bay, Alaska
This study assessed the importance of anthropogenic foods to the diets of red foxes and arctic foxes (Vulpes lagopus (L., 1758)), and competition for food resources between the two species in Prudhoe Bay. We used stable isotope analysis of fox tissues to infer diet during summer and winter for both red and arctic foxes, and lifetime diet for red fox. While the contribution of anthropogenic foods in late summer for both species’ diets was low (~10% to 15%), the contribution in late winter was higher and varied between species (red foxes = 49%; arctic foxes = 39%). Estimates of lifetime diet in red foxes suggest consis...
Source: Canadian Journal of Zoology - July 1, 2014 Category: Zoology Tags: article Source Type: research

Animal mitochondria: evolution, performance, and plasticity
Canadian Journal of Zoology, Volume 92, Issue 7, Page v-vi, July 2014. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - June 25, 2014 Category: Zoology Tags: article Source Type: research

Partial special issue containing invited papers arising from the symposium “Animal mitochondria: evolution, performance, and plasticity” held during the Canadian Society of Zoologists’ Annual Meeting, University of Guelph, 13–17 May 2013
Canadian Journal of Zoology, Volume 92, Issue 7, Page iii-iii, July 2014. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - June 25, 2014 Category: Zoology Tags: article Source Type: research

Energy metabolism and cytochrome oxidase activity: linking metabolism to gene expression
Canadian Journal of Zoology, e-First Articles. Modification of mitochondrial content demands the synthesis of hundreds of proteins encoded by nuclear and mitochondrial genomes. The responsibility for coordination of this process falls to nuclear-encoded master regulators of transcription. DNA-binding proteins and coactivators integrate information from energy-sensing pathways and hormones to alter mitochondrial gene expression. In mammals, the signaling cascade for mitochondrial biogenesis can be described as follows: hormonal signals and energetic information are sensed by protein-modifying enzymes that in turn regu...
Source: Canadian Journal of Zoology - June 21, 2014 Category: Zoology Tags: article Source Type: research

Anthropogenic food use and diet overlap between red foxes (Vulpes vulpes) and arctic foxes (Vulpes lagopus) in Prudhoe Bay, Alaska
This study assessed the importance of anthropogenic foods to the diets of red foxes and arctic foxes (Vulpes lagopus (L., 1758)), and competition for food resources between the two species in Prudhoe Bay. We used stable isotope analysis of fox tissues to infer diet during summer and winter for both red and arctic foxes, and lifetime diet for red fox. While the contribution of anthropogenic foods in late summer for both species’ diets was low (~10% to 15%), the contribution in late winter was higher and varied between species (red foxes = 49%; arctic foxes = 39%). Estimates of lifetime diet in red foxes suggest consis...
Source: Canadian Journal of Zoology - June 19, 2014 Category: Zoology Tags: article Source Type: research

Habitat use by giant pandas (Ailuropoda melanoleuca) in relation to roads in the Wanglang Nature Reserve, People’s Republic of China
Canadian Journal of Zoology, Volume 92, Issue 8, Page 715-719, August 2014. The impacts of roads on wildlife and their habitats have been widely recognized. To assess the effects of roads on habitat use of the giant panda (Ailuropoda melanoleuca (David, 1869)), we investigated the giant panda habitats and the roadside habitats in Wanglang Nature Reserve, People’s Republic of China. We found that giant pandas did not use the road-affected habitats, and compared with giant panda habitats, road-affected habitats were characterized by lower bamboo density and grazing disturbances. Therefore, our study demonstrated ...
Source: Canadian Journal of Zoology - June 17, 2014 Category: Zoology Tags: article Source Type: research

Daytime declines in rumen–reticulum fill of male white-tailed deer (Odocoileus virginianus) from south Texas
We examined whether there were daytime declines in rumen–reticulum fill in response to high ambient temperatures in free-ranging white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) on a diurnal scale. We hypothesized that to reduce heat-producing digestive processes in the heat of the day, rumen–reticulum fill and digestion in the rumen–reticulum would decline throughout the day. We collected the rumina and reticula of adult males and females across 30 h in two autumns in south Texas, USA. We also measured dry digesta mass, organ mass, and crude protein and acid detergent fiber concentrations of...
Source: Canadian Journal of Zoology - June 13, 2014 Category: Zoology Tags: article Source Type: research

Context dependence of elk (Cervus elaphus) vigilance and wolf (Canis lupus) predation risk
Canadian Journal of Zoology, Volume 92, Issue 8, Page 727-736, August 2014. To assess the relationship between predation risk perceived by elk (Cervus elaphus L., 1758) as evidenced by vigilance, we conducted focal animal observations in elk winter range. We stratified our observations in Glacier National Park, Montana, USA, and Waterton Lakes National Park, Alberta, Canada, in valleys with three wolf (Canis lupus L., 1758) population levels (Saint Mary Valley: no wolf; Waterton Valley: moderate wolf; North Fork Valley: high wolf). Although the lowest elk vigilance occurred in Saint Mary and the highest in the North ...
Source: Canadian Journal of Zoology - June 11, 2014 Category: Zoology Tags: article Source Type: research

Context dependence of elk (Cervus elaphus) vigilance and wolf (Canis lupus) predation risk
Canadian Journal of Zoology, e-First Articles. To assess the relationship between predation risk perceived by elk (Cervus elaphus L., 1758) as evidenced by vigilance, we conducted focal animal observations in elk winter range. We stratified our observations in Glacier National Park, Montana, USA, and Waterton Lakes National Park, Alberta, Canada, in valleys with three wolf (Canis lupus L., 1758) population levels (Saint Mary Valley: no wolf; Waterton Valley: moderate wolf; North Fork Valley: high wolf). Although the lowest elk vigilance occurred in Saint Mary and the highest in the North Fork, our analysis revealed a...
Source: Canadian Journal of Zoology - June 11, 2014 Category: Zoology Tags: article Source Type: research

Effect of habitat use and diet on the gastrointestinal parasite community of an avian omnivore from an urbanized environment
We examined the effect of habitat use and diet on gastrointestinal parasite assemblages of Ring-billed Gulls (Larus delawarensis Ord, 1815) breeding in an urbanized region (Montréal, Quebec, Canada) using three approaches depicting different temporal scales. Birds were fitted with global positioning system data loggers to determine habitat-use patterns during a 2–3 day period. Stomach contents were examined, providing dietary information during the preceding hours. Liver carbon (δ13C) and nitrogen (δ15N) stable isotope signatures served as proxy of nutrient assimilation during the preceding 10 days...
Source: Canadian Journal of Zoology - June 6, 2014 Category: Zoology Tags: article Source Type: research

Large testes and brain sizes in odontocetes (order Cetacea, suborder Odontoceti): the influence of mating system on encephalization
Canadian Journal of Zoology, Volume 92, Issue 8, Page 721-726, August 2014. Little is known about their mating systems, but odontocetes may utilize the same types of mating systems as terrestrial mammals. Species with relatively large testes are likely to be polygynandrous, while species with smaller testes and greater sexual size dimorphism (SSD) are predicted to be polygynous. The “Machiavellian intelligence or sexual conflict” hypothesis predicts that polygynadrous species also evolved larger brains both to coerce conspecifics to mate and to resist mating attempts by undesirable mates. The “costl...
Source: Canadian Journal of Zoology - June 6, 2014 Category: Zoology Tags: article Source Type: research

Timing is the only thing: reproduction in female yellow ground squirrels (Spermophilus fulvus)
Canadian Journal of Zoology, Volume 92, Issue 8, Page 737-747, August 2014. Based on 4-year field observations of yellow ground squirrels (Spermophilus fulvus (Lichtenstein, 1823)), we determined whether female reproductive effort, annual reproductive success, and survival were dependent on age, body condition, time of emergence from hibernation, and previous reproduction. The probability of weaning a litter did not vary with female age, body condition, time of emergence, or previous reproduction. Litter size, litter mass, and offspring survival did not vary with age, whereas individual offspring mass was lower in ye...
Source: Canadian Journal of Zoology - June 6, 2014 Category: Zoology Tags: article Source Type: research