TitleAbstractYear(sorted ascending)
the ornithodoros (alectorobius) capensis group (acarina: ixodoidea: argasidae) of the palearctic and oriental regions. o. (a.) maritimus: identity, marine bird hosts, virus infections, and distribution in western europe and northwestern 1967, vermeil and marguet described ornithodoros coniceps maritimus from larvae reared from larvae taken from marine birds on dumet island (atlantic ocean), basse bretagne, france. we collected o. (a.) coniceps canestrini, 1890, from the type locality (venice, italy) and determined that the taxons coniceps and maritimus each require full species status. we selected a lectotype and paralectotypes for the taxon maritimus from the original dumet island material. the larva of maritimus is redescr ...1976978368
shell thinning and residues of organochlorines and mercury in seabird eggs, eastern canada, 1970-76.organochlorine and mercury concentrations are reported for 252 eggs of leach's storm-petrel (oceanodroma leucorhoa), double-crested cormorant (phalarocorax auritus), common eider (somateria mollissima), common tern (sterna hirundo), razorbill (alca torda), common murre (uria aalge) black guillemot (cepphus grylle), and atlantic puffin (fratercula arctica) from the bay of fundy, the gulf of st. lawrence, and the open atlantic shore of canada during 1970-76. concentrations of all organochlorines e ...1979117427
a study of the hepatic microsomal monooxygenase of sea birds and its relationship to organochlorine pollutants.1. the levels of hepatic microsomal monooxygenase in sea birds were determined using organochlorine substrates. levels of cytochrome p450 and organochlorine residues were also measured. 2. the razorbill (alca torda) and puffin (fratercula arctica) showed highly variable activities which were resolved into multiple peaks on frequency diagrams. 3. the most active individuals amongst razorbills were early season females with large ovaries. 4. the properties of monooxygenase from individuals of low ...19826128175
hepatic metabolism of cyclodiene insecticides by constitutive forms of cytochrome p-450 from lower vertebrates.1. multiple forms of cytochrome p-450 were separated from the hepatic microsomes of untreated male rats, pigeons (columbia livia), razorbills (alca torda), puffins (fratercula arctica), and rainbow trout (salmo gairdnerii), using anion exchange chromatography and deae-cellulose. 2. in some cases cytochrome p-450 forms were further purified on hydroxylapatite and carboxymethyl-sephadex columns. 3. considerable differences in the distribution of forms between these five species were evident from e ...19872888582
metabolism of [14c]4-chlorobiphenyl by hepatic microsomes isolated from razorbills, pigeons and rats.1. analysis of individual pcb-isomers and congeners in extracts of adipose tissue from n = 12 razorbills suggested that 4-chlorobiphenyl was subjected to metabolism. 2. in vitro metabolism studies using [14c]-4-chlorobiphenyl as substrate showed that razorbills metabolise this substrate to [14c]4-chloro-4'-hydroxybiphenyl at an average rate of 20 pmol/mg microsomal protein/min. for comparison, the metabolism of [14c]-4-chlorobiphenyl by pigeons and rats was also studied, and average rates in the ...19911685399
species differences in avian serum b esterases revealed by chromatofocusing and possible relationships of esterase activity to pesticide toxicity.serum cholinesterase (bche) and carboxylesterase (cbe) activities were investigated in ten species of birds. multiple forms of serum bche and cbe were also separated by chromatofocusing. higher cbe activity and a wider range of cbe and bche forms were present in the sera of omnivorous/herbivorous birds than carnivores. omnivores/herbivores studied were the starling, house sparrow, tree sparrow, pigeon, partridge and magpie. serum cbe activities of these species ranged from 0.46 to 2.93 mumol/min ...19912009098
a lyme borreliosis cycle in seabirds and ixodes uriae ticks.the lyme disease spirochaete, borrelia burgdorferi s.l., is the only borrelia known to infect both mammals and birds. the main vertebrate reservoirs of b. burgdorferi are thought to be various small and intermediate size mammals, but the importance of birds as a reservoir has not been thoroughly explored. in the northern and southern hemispheres the seabird tick, ixodes uriae, is prevalent and closely associated with many species of colony-nesting marine birds. here we report the presence of spi ...19938455718
cytochrome b nucleotide sequence variation among the atlantic alcidae.analysis of cytochrome b nucleotide sequences of the six extant species of atlantic alcids and a gull revealed an excess of adenines and cytosines and a deficit of guanines at silent sites on the coding strand. phylogenetic analyses grouped the sequences of the common (uria aalge) and brünnich's (u. lomvia) guillemots, followed by the razorbill (alca torda) and little auk (alle alle). the black guillemot (cepphus grylle) sequence formed a sister taxon, and the puffin (fratercula arctica) fell ou ...19937916741
phylogeny and evolution of the auks (subfamily alcinae) based on mitochondrial dna sequences.the genetic divergence and phylogeny of the auks was assessed by mitochondrial dna sequence comparisons in a study using 19 of the 22 auk species and two outgroup representatives. we compared more than 500 nucleotides from each of two mitochondrial genes encoding 12s rrna and the nadh dehydrogenase subunit 6. divergence times were estimated from transversional substitutions. the dovekie (alle alle) is related to the razorbill (alca torda) and the murres (uria spp). furthermore, the xantus's murr ...19948058734
dispersal and distribution of the tick ixodes uriae within and among seabird host populations: the need for a population genetic approach.the aim of this study was to characterize the spatial distribution of the tick ixodes uriae within and among populations of its seabird hosts and to consider the potential insight that could be gained by a population genetic approach to the issue of dispersal of this tick. analyses of data collected around the avalon peninsula, newfoundland, indicated that both the prevalence and mean abundance of ticks varied significantly among sample locations. whereas ticks were found on all 4 host species e ...199910219295
genetic diversity and population history of two related seabird species based on mitochondrial dna control region sequences.geographical variation in two related seabird species, the razorbill (alca torda) and common guillemot (uria aalge), was investigated using sequence analysis of mitochondrial dna (mtdna) control regions. we determined the nucleotide sequence of the variable 5' segment of the control region in razorbills and common guillemots from breeding colonies across the atlantic ocean. the ecology and life history characteristics of razorbill and common guillemot are in many respects similar. they are both ...200111703652
mitochondrial control region structure and single site heteroplasmy in the razorbill (alca torda; aves).the primary structure of the alca torda mitochondrial control region was determined and conserved structural features were identified based on sequence comparisons to other bird species. in a population survey using control region analysis, five individuals were found to possess heteroplasmic point mutations at the variable 5' end of the control region. the pattern of variable nucleotide positions among individuals was compared to the distribution of heteroplasmic sites and the heteroplasmic con ...200111409182
nest-site safety predicts the relative investment made in first and replacement eggs by two long-lived seabirds.comparative studies of birds suggest that differences in nest-site characteristics, such as between open-nesting and cavity-nesting species, might ultimately underlie much interspecific variation in clutch size and renesting capacity. the "renesting hypothesis" holds that in species that typically enjoy high breeding success because they nest in safe sites, individuals maximize fitness by laying large first clutches early in the season while withholding few resources for renesting attempts. we t ...200128547602
mitochondrial dna sequence evolution and phylogeny of the atlantic alcidae, including the extinct great auk (pinguinus impennis).the atlantic auk assemblage includes four extant species, razorbill (alca torda), dovekie (alle alle), common murre (uria aalge), and thick-billed murre (u. lomvia), and one recently extinct species, the flightless great auk (pinguinus impennis). to determine the phylogenetic relationships among the species, a contiguous 4.2-kb region of the mitochondrial genome from the extant species was amplified using pcr. this region included one ribosomal rna gene, four transfer rna genes, two protein-codi ...200212200471
sex differences in razorbill alca torda parent-offspring vocal recognition.we investigated differences in parent-offspring vocal recognition between males and females in a natural population of razorbills alca torda, a long-lived and highly social species of auk (family: alcidae). razorbills provide biparental care to their chicks while at the nest site, after which the male is the sole caregiver for an additional period at sea. parent-offspring recognition in razorbills is most challenging once the chick becomes mobile, leaves the nest site and goes to sea with the ma ...200312456694
cadmium, zinc, copper, arsenic, selenium and mercury in seabirds from the barents sea: levels, inter-specific and geographical differences.trace elements cd, zn, cu, as, se and hg were analysed in muscle and liver of brünnich's guillemot, common guillemot, puffin, black guillemot, little auk, razorbill, common eider, king eider, glaucous gull, herring gull, black-legged kittiwake, northern fulmar and arctic tern collected in 1991-1992 at the main breeding colonies in the barents sea. the highest levels of the most toxic elements cd and hg were found in birds nesting north of spitsbergen. extremely high levels of as were detected in ...200312699923
seabirds as indicators of changes in marine ecosystems: ecological monitoring on machias seal island.changes in marine ecosystems can be manifested in many different ways, on different temporal and spatial scales. seabirds are top consumers in marine foodwebs and offer opportunities to detect and assess the biological effects of changes in physical parameters (sea-surface temperature [sst], salinity, depth of thermocline etc.) of the marine ecosystem. we compare six-eight years' of data on the biology (diet, and breeding success) of four species of seabird (arctic tern sterna paradisaea and com ...200314570414
polychlorinated biphenyl (pcb) congener concentrations in seabirds found dead in mortality incidents around the british coast.livers from 121 birds killed in mortality incidents in u.k. coastal waters between 1991 and 1996 were analyzed for 16 pcb congeners (iupac numbers 8, 18, 28, 31, 52, 77, 101, 118, 126, 128, 138, 149, 153, 169, 170, and 180). species analyzed were guillemot (uria aalge), shag (phalacrocorax arisotelis), kittiwake (rissa tridactyla), puffin (fratercula arctica), razorbill (alca torda), fulmar (fulmarus glacialis), gannet (sula bassana), and herring gull (larus argentatus). this is the first report ...200312948183
pathological features in marine birds affected by the prestige's oil spill in the north of spain.a total of 2,465 seabirds, mainly common murres (uria aalge), razorbills (alca torda), and puffins (fratercula arctica) that beached in the northwestern part of spain after the "prestige" oil spill on 19 november 2002 were examined by pathological methods. birds were divided into three groups: dead birds with the body covered (group 1) or uncovered (group 2) by oil and birds recovered alive but which died after being treated at a rescue center (group 3). the main gross lesions were severe dehydr ...200516107672
genetic evidence for the existence of sibling species within contracaecum rudolphii (hartwich, 1964) and the validity of contracaecum septentrionale (kreis, 1955) (nematoda: anisakidae).specimens of contracaecum rudolphii sensu lato (s.l.) (nematoda: anisakidae) from phalacrocorax carbo sinensis from northeastern and central italy were characterised genetically and compared with those from phalacrocorax aristotelis from galician coasts, spain (identified as c. rudolphii a by multilocus enzyme electrophoresis) and with specimens of c. septentrionale from alca torda from the galician coasts, spain. the first (its-1) and second (its-2) internal transcribed spacers (its) of ribosom ...200515928905
swim speeds and stroke patterns in wing-propelled divers: a comparison among alcids and a diving birds, the volume and resulting buoyancy of air spaces changes with dive depth, and hydrodynamic drag varies with swim speed. these factors are important in the dive patterns and locomotion of alcids that use their wings both for aerial flight and underwater swimming and of penguins that use their wings only for swimming. using small data-loggers on free-ranging birds diving to 20-30 m depth, we measured depth at 1 hz and surge and heave accelerations at 32-64 hz of four species of alc ...200616547294
heavy metal and arsenic content in seabirds affected by the prestige oil spill on the galician coast (nw spain).seabirds are top consumers in marine foodchains which offer opportunities to detect and assess the toxicological effects of different inorganic elements on the marine ecosystem. in order to provide baseline data concerning trace element levels in seabird species from nw spain, zinc, copper, arsenic, chromium, lead, cadmium and mercury concentrations were analyzed in liver of three different seabird species (common guillemot, atlantic puffin and razorbill) affected by the prestige oil spill in se ...200616696110
trends in chronic marine oil pollution in danish waters assessed using 22 years of beached bird surveys.beached bird surveys provide an important tool for monitoring the level of oil pollution at sea, which is the most significant observable cause of death for a large number of waterbird species and pose a serious threat to wintering seabird populations. linear regression analyses of oil rates from the danish 22 year dataset show a decline in the oil pollution level in offshore areas of the eastern north sea and skagerrak and in near-shore parts of the kattegat; but a worsening in the offshore are ...200717658558
acetylcholinesterase activity in seabirds affected by the prestige oil spill on the galician coast (nw spain).in november 2002, the tanker prestige broke in two and sank at the bottom of the ocean spilling about 70,000 t of fuel oil, which reached the coast of galicia. it was considered the largest spill in maritime history, greatly affecting marine and related avian species. the spilled fuel oil contained high concentrations of polycyclic aromatic hydrocarbons (pahs). many species were affected and were found dead, although ongoing research is still being carried out on the sublethal effects. in this s ...200717113132
perfluorinated compounds in some terrestrial and aquatic wildlife species from poland.perfluorooctanesulfonate (pfos) at 1.6-39 ng/g ww and 4.8-200 pg/ml, respectively, perfluorooctanoate (pfoa) at 0.06-0.28 ng/g ww and<0.05-1.8 pg/ml, and perfluorodecanoate (pfda) at 0.13-0.57 ng/g ww and 0.05-1.8 pg/ml, were detected in all specimens of european beaver's (castor fiber) liver as well as in whole blood of cod (gadus morhua), velvet scoter (melanitta fusca), eider duck (sommateria mollisima), long-tailed duck (clangula hyemalis), razorbill (alca torda), red-throated diver (gavia s ...200717473997
bioaccumulation of polonium 210po in marine birds.the aim of this work was to determine the 210po content in marine birds which permanently or temporally live in the polish part of the baltic sea. we chose 11 species of sea birds: three species permanently residing at southern baltic sea, four species of wintering birds and three species of migrating birds. the results show that the polonium is non-uniformly distributed in the marine birds. the highest activities of 210po were observed in feathers, muscles and liver and the lowest in skin and s ...200717267081
marine foraging birds as bioindicators of mercury in the gulf of maine.from existing databases, we compiled and evaluated 604 total mercury (hg) levels in the eggs and blood of 17 species of marine foraging birds from 35 gulf of maine islands to provide baseline data and to determine the best tissue, age class, and species for future biomonitoring. while mean hg levels in most species did not exceed adverse effects thresholds, levels in some individual eggs did; for all species arithmetic mean egg hg levels ranged from 0.04 to 0.62 (microg/g, wet weight). piscivoro ...200819277786
mercury concentrations in seabird tissues from machias seal island, new brunswick, canada.mercury is a pervasive environmental contaminant, the anthropogenic portion of which is increasing globally, and in northeastern north america in particular. seabirds frequently are used as indicators of the marine environment, including mercury contamination. we analysed paired samples for total mercury (hg) concentrations in feathers and blood from adult and chick, albumen, and lipid-free yolk of seven seabirds breeding on machias seal island, new brunswick, canada - arctic tern (sterna paradi ...200919419752
toxic element concentrations in the razorbill alca torda (charadriiformes, alcidae) in portugal.the present study provides the first data on inorganic element levels (as, cd, co, cr, cu, hg, mn, pb, se, and zn) in juvenile, immature, and adult razorbills (alca torda) collected along the central coast of portugal. element concentrations were assessed by icp-ms in kidney, liver, muscle, and feathers of 28 razorbills, including 4 juveniles, 17 subadults, and 7 adults. the effect of age and tissue on element accumulation was also assessed. the detected levels in razorbills may indicate a possi ...200918712496
assessment of organochlorine pesticide exposure in a wintering population of razorbills (alca torda) from the southwestern mediterranean.sixteen organochlorine pesticides (oc) were analyzed in several tissue types (abdominal and subcutaneous fat, liver and brain) from juvenile (n=14), immature (n=9), subadult (n=7) and adult (n=20) razorbill (alca torda) collected from the southwestern mediterranean coastline, in the east of spain (la marina, elche, alicante, spain). these razorbills had drowned in fishing nets (most probably) while searching for food. the objective was to assess the exposure to organochlorine pesticide residues ...201020619440
how did the great auk raise its young?the extant auks show three strategies of chick rearing--precocial (chicks leave the nest site when a few days old), intermediate (young raised to a mass of around 20% of adult mass) and semi-precocial (young raised to a mass of around 65% of adult mass). it is not known which strategy the extinct great auk used. in this paper, we investigate this issue by a novel combination of a time and energy budget model and phylogenetic comparison. the first approach indicates that for reasonable estimates ...201020695972
impacts of poor food availability on positive density dependence in a highly colonial seabird.for species with positive density dependence, costs and benefits of increasing density may depend on environmental conditions, but this has seldom been tested. by examining a colonial seabird (common guillemot) over a period of unprecedented poor food availability, we test two contrasting hypotheses suggesting that birds breeding at high density have: (i) greater leeway to increase foraging effort owing to more effective defence of unattended chicks against predators; and (ii) less leeway, owing ...201020335206
influence of wing loading on the trade-off between pursuit-diving and flight in common guillemots and razorbills.species of bird that use their wings for underwater propulsion are thought to face evolutionary trade-offs between flight and diving, leading to the prediction that species with different wing areas relative to body mass (i.e. different wing loadings) also differ in the relative importance of flight and diving activity during foraging trips. we tested this hypothesis for two similarly sized species of alcidae (common guillemots and razorbills) by using bird-borne devices to examine three-dimensi ...201020228337
razorbill (alca torda) feathers as an alternative tool for evaluating exposure to organochlorine pesticides.the aim of this study was to explore the usefulness of feathers as a biomonitoring tool for organochlorine pesticides (oc) in a razorbill population (alca torda). fifteen oc were analyzed in feathers, including α-, β- and δ-hexachlorocyclohexane, lindane, aldrin, dieldrin, endrin, endosulfan i and ii, endosulfan sulfate, p,p'-ddt, ddd, dde, heptachlor and its epoxide. the geometric mean concentrations observed in this study were ∑ddt 67.40 ng/g, ∑hch 62.88 ng/g, ∑heptachlor 61.75 ng/g, ∑endosulf ...201221894567
razorbills (alca torda) as bioindicators of mercury pollution in the southwestern mediterranean.levels of mercury (hg) were analyzed in the tissues of 50 razorbills (alca torda), from the mediterranean area, which had drowned in fishing nets. the mercury distribution pattern in tissues was similar to those of other studies (liver > feather vane > kidney > muscle > brain > feather shaft), with mercury concentrations of 2.85 ± 0.90, 2.66 ± 1.60, 2.23 ± 0.87, 1.54 ± 0.54, 1.48 ± 0.54 and 1.30 ± 0.76 mg/kg (dry weight), respectively. it could be considered that razorbills in the southwestern m ...201222935523
influence of climate change and trophic coupling across four trophic levels in the celtic sea.climate change has had profound effects upon marine ecosystems, impacting across all trophic levels from plankton to apex predators. determining the impacts of climate change on marine ecosystems requires understanding the direct effects on all trophic levels as well as indirect effects mediated by trophic coupling. the aim of this study was to investigate the effects of climate change on the pelagic food web in the celtic sea, a productive shelf region in the northeast atlantic. using long-term ...201223091621
modelling the effects of prey size and distribution on prey capture rates of two sympatric marine predators.understanding how prey capture rates are influenced by feeding ecology and environmental conditions is fundamental to assessing anthropogenic impacts on marine higher predators. we compared how prey capture rates varied in relation to prey size, prey patch distribution and prey density for two species of alcid, common guillemot (uria aalge) and razorbill (alca torda) during the chick-rearing period. we developed a monte carlo approach parameterised with foraging behaviour from bird-borne data lo ...201324260318
sympatric breeding auks shift between dietary and spatial resource partitioning across the annual cycle.when species competing for the same resources coexist, some segregation in the way they utilize those resources is expected. however, little is known about how closely related sympatric breeding species segregate outside the breeding season. we investigated the annual segregation of three closely related seabirds (razorbill alcatorda, common guillemot uriaaalge and brünnich's guillemot u. lomvia) breeding at the same colony in southwest greenland. by combining gps and geolocation (gls) tracking ...201324023663
evaluation of seabirds in newfoundland and labrador, canada, as hosts of influenza a viruses.influenza a viruses infect a wide range of hosts, including many species of birds. avian influenza a virus (aiv) infection appears to be most common in anseriformes (ducks, geese, and swans) and some charadriiformes (shorebirds and gulls), but many other birds also serve as hosts of aiv. here, we evaluated the role of seabirds as hosts for aiv. we tested 3,160 swab samples from 13 seabird species between may 2008 and december 2011 in newfoundland and labrador, canada. we also tested 156 serum sa ...201424171570
osteological histology of the pan-alcidae (aves, charadriiformes): correlates of wing-propelled diving and flightlessness.although studies of osteological morphology, gross myology, myological histology, neuroanatomy, and wing-scaling have all documented anatomical modifications associated with wing-propelled diving, the osteohistological study of this highly derived method of locomotion has been limited to penguins. herein we present the first osteohistological study of the derived forelimbs and hind limbs of wing-propelled diving pan-alcidae (aves, charadriiformes). in addition to detailing differences between wi ...201424357466
trace element concentrations in harvested auks from newfoundland: toxicological risk of a traditional hunt.common (uria aalge) and thick-billed murres (uria lomvia) are apex predators in the north atlantic ocean, and are also subject to a traditional hunt in newfoundland and labrador during the winter months, along with small numbers of illegally harvested razorbills (alca torda). because of their high trophic position, auks are at risk from high contaminant burdens that bioaccumulate and biomagnify, and could therefore pose a toxicological risk to human consumers. we analysed trace element concentra ...201525666730
mercury in wintering seabirds, an aggravating factor to winter wrecks?every year, thousands of seabirds are cast ashore and are found dead along the coasts of north america and western europe. these massive mortality events called 'winter wrecks' have generally been attributed to harsh climatic conditions and prolonged storms which affect bird energy balance and impact their body condition. nevertheless, additional stress factors, such as contaminant body burden, could potentially cumulate to energy constraints and actively contribute to winter wrecks. however, th ...201525984703
the use of an unsupervised learning approach for characterizing latent behaviors in accelerometer data.the recent increase in data accuracy from high resolution accelerometers offers substantial potential for improved understanding and prediction of animal movements. however, current approaches used for analysing these multivariable datasets typically require existing knowledge of the behaviors of the animals to inform the behavioral classification process. these methods are thus not well-suited for the many cases where limited knowledge of the different behaviors performed exist. here, we introd ...201626865961
foraging flexibility and search patterns are unlinked during breeding in a free-ranging order to maximize foraging efficiency in a varying environment, predators are expected to optimize their search strategy. environmental conditions are one important factor affecting these movement patterns, but variations in breeding constraints (self-feeding vs. feeding young and self-feeding) during different breeding stages (incubation vs. chick-rearing) are often overlooked, so that the mechanisms responsible for such behavioral shifts are still unknown. here, to test how search patterns ...201727069278
breeding density, fine-scale tracking, and large-scale modeling reveal the regional distribution of four seabird species.population-level estimates of species' distributions can reveal fundamental ecological processes and facilitate conservation. however, these may be difficult to obtain for mobile species, especially colonial central-place foragers (ccpfs; e.g., bats, corvids, social insects), because it is often impractical to determine the provenance of individuals observed beyond breeding sites. moreover, some ccpfs, especially in the marine realm (e.g., pinnipeds, turtles, and seabirds) are difficult to obser ...201728653410
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