| the elusive source of psittacosis in the arctic. | eskimos and arctic indians have a high incidence of psittacosis antibodies. the following arctic birds were therefore examined in an endeavour to find the reservoir of infection: snow geese in their arctic nesting grounds; migrating geese in the spring and in the fall; ptarmigan, raven, and snow bunting on the arctic circle in the late winter. psittacosis virus was not recovered from any of the birds examined, but a percentage of migrating geese had psittacosis antibodies. the source of human an ... | 1965 | 5844422 |
| [the diurnal activity of starlings (sturnus vulgaris) and snow-buntings (plectrophenax nivalis)]. | starlings (sturnus vulgaris) and snow-buntings (plectrophenax nivalis) were observed during their period of reproduction. the flying-activity at the nest-hole was automatically recorded.the amount of activity of starlings during feedingtime is dependent on the number of nestlings.the activity-pattern of starlings changes in the course of spring and early summer: 1. at pair-time starlings normally arrive at the nest-holes in the early moring, and one steep peak of activity is characteristic for t ... | 1968 | 28306853 |
| the intensity of interference varies with food density: support for behaviour-based models of interference. | dolman (1995) measured the intake rates of snow buntings feeding on seed patches at difference bird densities, for each of two different seed densities. interference occurred in the low food density treatment, with intake rate declining at high bird densities, but did not occur in the high food density treatment. dolman states that existing models of the interference process assume that the intensity of interference is independent of food density. while this statement is true for the model of ha ... | 1996 | 28307860 |
| hormones and territorial behavior during breeding in snow buntings (plectrophenax nivalis): an arctic-breeding songbird. | we examined hormonal profiles and behavior associated with maintaining a single-purpose territory in an arctic-breeding songbird-the snow bunting (plectrophenax nivalis). snow buntings differ from many other arctic-breeding passerines by using nest cavities, an uncommon and defended resource, but not relying upon the surrounding territory for forage. circulating levels of testosterone in males were high when territories were established and then decreased over the breeding season. lh secretion w ... | 1998 | 9571012 |
| the oxidative costs of territory quality and offspring provisioning. | the costs of reproduction are an important constraint that shapes the evolution of life histories, yet our understanding of the proximate mechanism(s) leading to such life-history trade-offs is not well understood. oxidative stress is a strong candidate measure thought to mediate the costs of reproduction, yet empirical evidence supporting that increased reproductive investment leads to oxidative stress is equivocal. we investigated whether territory quality and offspring provisioning increase o ... | 2013 | 24118294 |
| basal and maximal metabolic rates differ in their response to rapid temperature change among avian species. | in birds, acclimation and acclimatization to temperature are associated with changes in basal (bmr), summit (msum) and maximal (mmr) metabolic rates but little is known about the rate at which species adjust their phenotype to short-term temperature variations. our aims were (1) to determine the pattern of metabolic adjustments following a rapid temperature change, (2) to determine whether performance varies at similar rates during exposure to warm or cold environments, and (3) to determine if b ... | 2016 | 27233918 |
| isospora plectrophenaxia n. sp (apicomplexa: eimeriidae), a new coccidian parasite found in snow bunting (plectrophenax nivalis) nestlings on spitsbergen. | faecal samples were collected from four 8 days old snow bunting nestlings from one nest in ny-alesund, spitsbergen, in summer 2006. after sporulation, samples were examined for coccidian parasites using flotation centrifuging. we found isosporan oocysts in three birds, intensity of infection varied between individuals from 35 to 6,000 oocysts per defecation. all oocysts belonged to one species, which is described here as a new species. the spherical or subspherical oocysts (fig. 1) have a browni ... | 2007 | 17701217 |
| contamination of an arctic terrestrial food web with marine-derived persistent organic pollutants transported by breeding seabirds. | at cape vera, devon island (nunavut, canada), a colony of northern fulmars (fulmarus glacialis) concentrates and releases contaminants through their guano to the environment. we determined whether persistent organic pollutants (pops) from seabirds were transferred to coastal food webs. snow buntings (plectrophenax nivalis) were the most contaminated species, with ∑pcb and ∑ddt (mean: 168, 106 ng/g ww) concentrations surpassing environmental guidelines for protecting wildlife. when examined colle ... | 2010 | 20801564 |
| longspurs and snow buntings: phylogeny and biogeography of a high-latitude clade (calcarius). | using complete cytochrome b sequence data, we determined that the genus calcarius, as presently recognized, is paraphyletic. calcarius plus plectrophenax form a highly supported clade composed of two subclades, a "snow bunting" clade comprised of plectrophenax plus calcarius mccownii (formerly in the monotypic genus rhynchophanes), and a "collared" longspur clade of calcarius lapponicus, ornatus, and pictus. contrary to conventional thought, calcarius is not phylogenetically close to either cala ... | 2003 | 12565028 |
| breeding on the extreme edge: modulation of the adrenocortical response to acute stress in two high arctic passerines. | arctic weather in spring is unpredictable and can also be extreme, so arctic-breeding birds must be flexible in their breeding to deal with such variability. unpredictability in weather conditions will only intensify with climate change and this in turn could affect reproductive capability of migratory birds. adjustments to coping strategies are therefore crucial, so here we examined the plasticity of the adrenocorticotropic stress response in two arctic songbird species-the snow bunting (plectr ... | 2015 | 25757443 |
| ultraconserved elements (uces) illuminate the population genomics of a recent, high-latitude avian speciation event. | using a large, consistent set of loci shared by descent (orthologous) to study relationships among taxa would revolutionize among-lineage comparisons of divergence and speciation processes. ultraconserved elements (uces), highly conserved regions of the genome, offer such genomic markers. the utility of uces for deep phylogenetics is clearly established and there are mature analytical frameworks available, but fewer studies apply uces to recent evolutionary events, creating a need for additional ... | 2018 | 30310754 |
| snow buntings (plectrophenax nivealis) as bio-indicators for exposure differences to legacy and emerging persistent organic pollutants from the arctic terrestrial environment on svalbard. | eggs of snow buntings (plectrophenax nivealis) were applied as a bio-indicator to examine differences in exposure to legacy persistent organic pollutants (pops) and perflouroalkyl subtances (pfas) from the terrestrial environment surrounding the settlements of longyearbyen, barentsburg and pyramiden on svalbard, norway. significantly higher concentrations of summed polychlorinated biphenyls (sumpcb7) in eggs collected from barentsburg (2980 ng/g lipid weight (lw)) and pyramiden (3860 ng/g lw) co ... | 2019 | 30833262 |
| whole genome sequencing of an avipoxvirus associated with infections in a group of aviary-housed snow buntings (plectrophenax nivalis). | avipoxvirus infections have been reported in both free-ranging and domestic birds worldwide. fowlpox and canarypox viruses belong to the genus avipoxvirus among the virus family poxviridae. they cause cutaneous lesions with proliferative growths on the unfeathered parts of the skin and/or diphtheritic lesions generally associated with necrosis in the upper respiratory and digestive tracts. in this study, a poxvirus has been identified in wild-caught snow buntings (plectrophenax nivalis) housed i ... | 2020 | 31926510 |
| wintering snow buntings elevate cold hardiness to extreme levels but show no changes in maintenance costs. | abstractresident temperate passerines adjust their phenotypes to cope with winter constraints, with peak performance in metabolic traits typically occurring during the coldest months. however, it is sparsely known whether cold-adapted northern species make similar adjustments when faced with variable seasonal environments. life in near-constant cold could be associated with limited flexibility in traits underlying cold endurance. we investigated this by tracking individual physiological changes ... | 2020 | 33048603 |
| the intensity of interference varies with resource density: evidence from a field study with snow buntings, plectrophenax nivalis. | intake rates of snow buntings feeding on artificial seed patches were measured at different bird densities, for each of two different seed densities. interference occurred in the low seed-density treatment, with intake rates declining at high bird densities. however, interference was not found in the high seeddensity treatment. the finding that the strength of interference may depend on resource density contradicts the hypothesis that the functional response is ratio-dependent (arditi and akçaka ... | 1995 | 28306895 |
| magnetic orientation of snow buntings (plectrophenax nivalis), a species breeding in the high arctic: passage migration through temperate-zone areas | orientation tests were conducted with snow buntings (plectrophenax nivalis) exposed to artificially manipulated magnetic fields, during both spring and autumn migration. experiments were run under clear sunset skies and under simulated complete overcast. the birds closely followed experimental shifts of the magnetic fields during both seasons regardless of whether they had access to celestial cues. clear-sky tests in vertical magnetic fields resulted in a significant bimodal orientation, the dir ... | 1996 | 9319809 |
| orientation of snow buntings (plectrophenax nivalis) close to the magnetic north pole | orientation experiments were performed with first-year snow buntings (plectrophenax nivalis) during their autumn migration in a natural near-vertical geomagnetic field approximately 400 km away from the magnetic north pole. migratory orientation of snow buntings was recorded using two different techniques: orientation cage tests and free-flight release experiments. experiments were performed under clear skies, as well as under natural and simulated complete overcast. several experimental manipul ... | 1998 | 9600868 |
| changes in pituitary and adrenal sensitivities allow the snow bunting (plectrophenax nivalis), an arctic-breeding song bird, to modulate corticosterone release seasonally. | several free-living avian species have recently been shown to seasonally modulate corticosterone release in response to capture and restraint. we examined possible mechanisms underlying seasonal adrenocortical modulation in snow buntings (plectrophenax nivalis), a species that breeds and molts (the energetically costly replacement of feathers) in the alaskan arctic snow buntings dramatically reduced baseline and maximal corticosterone titers during molt compared to the breeding season. this effe ... | 1998 | 9706705 |
| keeping the clock set under the midnight sun: diurnal periodicity and synchrony of avian isospora parasites cycle in the high arctic. | for isospora (protozoa: eimeriidae) parasites of passerine birds, diurnal periodicity of oocyst output is a well-described phenomenon. from the temporal zone to the tropics, oocyst production is correlated with the light-dark cycle, peaking in the afternoon hours. however, nothing is known about the existence of diurnal periodicity of these parasites in the birds of high arctic environments, under permanent light during summer. we sampled free-ranging snow bunting (aves: passeriformes), on svalb ... | 2011 | 21756419 |
| the bird ectoparasite dermanyssus hirundinis (acari, mesostigmata) in the high arctic; a new parasitic mite to spitsbergen, svalbard. | ectoparasites are common on birds and in their nests. amongst these parasites are diverse gamasid mite species that can lead to irritation, disease transmission and blood loss. few studies of the ectoparasites of birds breeding in the high arctic exist. the parasitic mite, dermanyssus hirundinis, was found in nests of snow buntings plectrophenax nivalis nivalis, both natural nests and within nesting boxes, on spitsbergen. densities per nest varied from sporadic to greater than 26,000 individuals ... | 2012 | 23129197 |
| diversification at high latitudes: speciation of buntings in the genus plectrophenax inferred from mitochondrial and nuclear markers. | high-latitude diversification is a process characterized by speciation and extinction due to climatically driven vicariance and dispersal events. mckay's buntings (plectrophenax hyperboreus) are high-latitude island endemic songbirds, and their global range is restricted to beringia. snow buntings (p. nivalis), their closest relatives, are distributed throughout the holarctic, breeding in available habitat surrounding the island range of mckay's buntings. we sequenced 1123 base pairs of mitochon ... | 2010 | 20088885 |
| a phylogenetically controlled test of hypotheses for behavioral insensitivity to testosterone in birds. | in most male birds that exhibit paternal care, extending the spring testosterone (t) peak throughout the breeding season reduces nestling provisioning. however, in some species, this trade-off between high t and expression of paternal care is absent. for example, during some or all of the nestling period, t did not affect paternal behavior in male lapland longspurs (calcarius lapponicus), chestnut-collared longspurs (calcarius ornatus), and great tits (parus major). two ecological constraints ha ... | 2005 | 15664020 |
| interspecific comparison of the fecal microbiota structure in three arctic migratory bird species. | the gut microbiota of birds is known to be characterized for different species, although it may change with feeding items. in this study, we compared the gut microbiota of birds with different feeding behaviors in the same habitat. we collected fecal samples from three arctic species, snow buntings plectrophenax nivalis, sanderlings calidris alba, and pink-footed geese anser brachyrhynchus that are phylogenetically quite distant in different families to evaluate effects of diet on gut microbiota ... | 2020 | 32607176 |
| from svalbard to siberia: passerines breeding in the high arctic also endure the extreme cold of the western steppe. | few species are adapted to high latitudes, and many over-winter in milder climates with migrations involving extensive barrier crossings. by escaping extreme conditions for the majority of the year, physiological and behavioural adaptations presumably need to be less pronounced. the snow bunting plectrophenax nivalis is the most northerly breeding passerine. we tracked the svalbard population using geolocators to reveal that these individuals not only breed in environmental extremes, but also sp ... | 2018 | 30183717 |
| first report of bean common mosaic necrosis potyvirus (bcmnv) infecting common bean in california. | during the 1996 growing season (june to september) an outbreak of bean common mosaic was detected in a navy bean field (cv. snow bunting) in colusa county, ca. early field inspections (august 1996) revealed an incidence of 5 to 10% infection, whereas a late field inspection (september) showed an incidence of 70 to 90% infection. enzyme-linked immunosorbent assay (elisa) was performed on 18 leaf samples from symptomatic plants collected from this field with two monoclonal antibodies (mab): mab i- ... | 1997 | 30861908 |