Publications

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chlordane components and metabolites in seven species of arctic seabirds from the northwater polynya: relationships with stable isotopes of nitrogen and enantiomeric fractions of chiral components.the northwater polynya (now) is a large area of year-round open water found in the high arctic between ellesmere island and greenland. now has high biological productivity compared with other arctic marine areas, and supports large populations of several seabird species. seven species of seabirds, dovekie (alle alle, dove), thick-billed murre (uria lomvia, tbmu), black guillemot (cepphus grylle, blgu), black-legged kittiwake (rissa tridactyla, blki), ivory gull (pagophila eburnea, ivgu), glaucou ...200111383340
examination of the bioaccumulation of halogenated dimethyl bipyrroles in an arctic marine food web using stable nitrogen isotope analysis.concentrations of four possibly naturally produced organohalogens--1,1'-dimethyl-3,3',4-tribromo-4,5,5'-trichloro-2,2'-bipyrrole (dbp-br3cl3), 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-dichloro-2,2'-bipyrrole (dbp-br4cl2), 1,1'-dimethyl-3,3',4,4',5-pentabromo-5'-chloro-2,2'-bipyrrole (dbp-br5cl) and 1,1'-dimethyl-3,3',4,4',5,5'-hexabromo-2,2'-bipyrrole (dbp-br6)--were quantitated and the extent of their magnification through an entire arctic marine food web [measured as integrated trophic magnific ...200211808557
organochlorine contaminants in seven species of arctic seabirds from northern baffin bay.organochlorine contaminants (ocs) were determined in liver and fat of seven species of seabirds (alle alle, uria lomvia, cepphus grylle, rissa tridactyla, pagophila eburnea, larus hyperboreus, and fulmaris glacialis) collected in may/june 1998 from the northwater polynya in northern baffin bay. oc concentrations ranged over an order of magnitude between seabird species and oc groups, with pcbs having the highest concentrations followed by ddt, chlordane, hch and clbz. positive relationships betw ...200414720475
bioaccumulation of pcbs in arctic seabirds: influence of dietary exposure and congener biotransformation.four seabird species and their prey (zooplankton or fish) were collected in the barents sea to determine how dietary exposure, cytochrome p450 (cyp) enzyme activities and sex influenced their hepatic pcb concentrations and accumulation patterns. five males and five females from each seabird species (little auk (alle alle), brunnich's guillemot (uria lomvia), black guillemot (cepphus grylle) and black-legged kittiwake (rissa tridactyla)) were analysed. pcb concentrations could not be explained di ...200515620585
selective bioaccumulation of chlorinated pesticides and metabolites in arctic seabirds.chlorinated pesticides and metabolites (cps) were quantified in the seabird species: little auk (alle alle), brünnich's guillemot (uria lomvia), black guillemot (cepphus grylle) and black-legged kittiwake (rissa tridactyla). the purpose was to evaluate avian accumulation of selected cps based on their concentrations and relative patterns, their relation to dietary descriptors (stable isotopes of carbon and nitrogen), to enzymes involved in biotransformation, as well as cps' accumulation potentia ...200716890332
regional and species specific bioaccumulation of major and trace elements in arctic seabirds.twenty-five essential and nonessential elements were analyzed in arctic seabirds to study the influence of phylogeny, tissue, arctic region, and diet on avian element accumulation and to identify co-occurrence among metals. muscle and liver concentrations were positively correlated, generally being higher in liver than in muscle, and generally did not differ by sex. zinc showed the highest absolute concentrations in all samples (mean, 11.2-26.7 microg/g in muscle, depending on species and area), ...200617089716
thermodynamic modelling predicts energetic bottleneck for seabirds wintering in the northwest atlantic.studying the energetics of marine top predators such as seabirds is essential to understand processes underlying adult winter survival and its impact on population dynamics. winter survival is believed to be the single most important life-history trait in long-lived species but its determinants are largely unknown. seabirds are inaccessible during this season, so conventional metabolic studies are extremely challenging and new approaches are needed. this paper describes and uses a state-of-the-a ...200919617442
the significance of the north water polynya to arctic top predators.the north water polynya (~76°n to 79°n and 70°w to 80°w) is known to be an important habitat for several species of marine mammals and sea birds. for millennia, it has provided the basis for subsistence hunting and human presence in the northernmost part of baffin bay. the abundance of air-breathing top predators also represents a potential source of nutrient cycling that maintains primary production. in this study, aerial surveys conducted in 2009 and 2010 were used for the first time to map th ...201223271401
enterobacter cloacae with a novel variant of act ampc beta-lactamase originating from glaucous gull (larus hyperboreus) in svalbard.we aimed at escherichia coli and enterobacter cloacae isolates resistant to cephalosporins and fluoroquinolones and salmonella isolates in wild birds in arctic svalbard, norway. cloacal swabs of little auks (alle alle, n=215) and samples of faeces of glaucous gulls (larus hyperboreus, n=15) were examined. inducible production of ampc enzyme was detected in e. cloacae kw218 isolate. sequence analysis of the 1146 bp pcr product of the ampc gene from this isolate revealed 99% sequence homology with ...201424629772
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
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
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
small birds, big effects: the little auk (alle alle) transforms high arctic ecosystems.in some arctic areas, marine-derived nutrients (mdn) resulting from fish migrations fuel freshwater and terrestrial ecosystems, increasing primary production and biodiversity. less is known, however, about the role of seabird-mdn in shaping ecosystems. here, we examine how the most abundant seabird in the north atlantic, the little auk (alle alle), alters freshwater and terrestrial ecosystems around the north water polynya (now) in greenland. we compare stable isotope ratios (δ(15)n and δ(13)c) ...201728202811
differential responses of arctic vegetation to nutrient enrichment by plankton- and fish-eating colonial seabirds in spitsbergen.the role of seabirds as sea-land biovectors of nutrients is well documented. however, no studies have examined whether and how colonial seabirds that differ in diet may influence terrestrial vegetation. therefore, the purpose of the study was to describe and compare plant communities located in the vicinity of the two most common types of seabird colonies in arctic, occupied by piscivorous or planktivorous species. within 46 plots arranged in four transects in the vicinity of planktivorous (litt ...201628083002
low density of top predators (seabirds and marine mammals) in the high arctic pack ice.the at-sea distribution of top predators, seabirds and marine mammals, was determined in the high arctic pack ice on board the icebreaker rv polarstern in july to september 2014. in total, 1,620 transect counts were realised, lasting 30 min each. the five most numerous seabird species represented 74% of the total of 15,150 individuals registered: kittiwake rissa tridactyla, fulmar fulmarus glacialis, puffin fratercula arctica, ross's gull rhodostethia rosea, and little auk alle alle. eight cetac ...201627777810
the arctic soil bacterial communities in the vicinity of a little auk colony.due to deposition of birds' guano, eggshells or feathers, the vicinity of a large seabirds' breeding colony is expected to have a substantial impact on the soil's physicochemical features as well as on diversity of vegetation and the soil invertebrates. consequently, due to changing physicochemical features the structure of bacterial communities might fluctuate in different soil environments. the aim of this study was to investigate the bacterial assemblages in the arctic soil within the area of ...201627667982
microplastic pollution in the greenland sea: background levels and selective contamination of planktivorous diving seabirds.microplastics have been reported everywhere around the globe. with very limited human activities, the arctic is distant from major sources of microplastics. however, microplastic ingestions have been found in several arctic marine predators, confirming their presence in this region. nonetheless, existing information for this area remains scarce, thus there is an urgent need to quantify the contamination of arctic marine waters. in this context, we studied microplastic abundance and composition w ...201627616650
a study of wrecked dovekies (alle alle) in the western north atlantic highlights the importance of using standardized methods to quantify plastic ingestion.quantification of plastic ingestion across a range of seabirds is required to assess the prevalence of plastics in marine food webs. we quantified plastic ingestion in beached dovekies (alle alle), following a wreck in newfoundland, canada. of 171 birds, 30.4% had ingested plastic (mean 0.81±0.30 se pieces per bird, mass 0.005±0.002 se g per bird). most plastics were fragments of polyethylene and polypropylene. surprisingly, 37% were burned or melted, indicating a previously unreported source of ...201627609235
does temporal variation of mercury levels in arctic seabirds reflect changes in global environmental contamination, or a modification of arctic marine food web functioning?studying long-term trends of contaminants in arctic biota is essential to better understand impacts of anthropogenic activities and climate change on the exposure of sensitive species and marine ecosystems. we concurrently measured temporal changes (2006-2014) in mercury (hg) contamination of little auks (alle alle; the most abundant arctic seabird) and in their major zooplankton prey species (calanoid copepods, themisto libellula, gammarus spp.). we found an increasing contamination of the food ...201626798998
diversification of nitrogen sources in various tundra vegetation types in the high arctic.low nitrogen availability in the high arctic represents a major constraint for plant growth, which limits the tundra capacity for carbon retention and determines tundra vegetation types. the limited terrestrial nitrogen (n) pool in the tundra is augmented significantly by nesting seabirds, such as the planktivorous little auk (alle alle). therefore, n delivered by these birds may significantly influence the n cycling in the tundra locally and the carbon budget more globally. moreover, should the ...201526376204
supplementary diet components of little auk chicks in two contrasting regions on the west spitsbergen coast.the complete diet composition structure of the most numerous planktivorous sea bird, little auk (alle alle), in the european arctic, is still not fully recognized. although regular constituents of little auk chick diets, the copepods, calanus glacialis and c. finmarchicus have been previously relatively well described, more taxa were frequent ingredients of the bird's meals. therefore, the role of the little auks supplementary diet components (sdcs) at two colonies in the svalbard archipelago, h ...201726069395
arctic warming: nonlinear impacts of sea-ice and glacier melt on seabird foraging.arctic climate change has profound impacts on the cryosphere, notably via shrinking sea-ice cover and retreating glaciers, and it is essential to evaluate and forecast the ecological consequences of such changes. we studied zooplankton-feeding little auks (alle alle), a key sentinel species of the arctic, at their northernmost breeding site in franz-josef land (80°n), russian arctic. we tested the hypothesis that little auks still benefit from pristine arctic environmental conditions in this rem ...201525639886
trace elements and ingested plastic debris in wintering dovekies (alle alle).we provide the first report on winter concentrations of 32 trace metals from dovekies (alle alle), a small, arctic seabird that has a seasonal shift in diet from small zooplankton in the breeding season to larger zooplankton and small fish in the non-breeding season. concentrations of selected trace elements, as well as stable carbon (δ(13)c) and nitrogen (δ(15)n) isotope concentrations for a sample of 25 dovekies, were similar between adult males and females, and there was evidence that dovekie ...201525499966
effect of diet, location and sampling year on bioaccumulation of mercury, selenium and cadmium in pelagic feeding seabirds in svalbard.hepatic concentrations of mercury (hg), selenium (se) and cadmium (cd) were determined in black-legged kittiwakes (rissa tridactyla) and little auks (alle alle) from two fjords in svalbard (kongsfjorden; 78°57'n, 12°12'e and liefdefjorden; 79°37'n, 13°20'e). the inflow of arctic and atlantic water differs between the two fjords, potentially affecting element accumulation. trophic positions (tp) were derived from stable nitrogen isotope ratios (δ(15)n), and stable carbon isotope ratios (δ(13)c) w ...201525441931
climate warming decreases the survival of the little auk (alle alle), a high arctic avian predator.delayed maturity, low fecundity, and high adult survival are traits typical for species with a long-life expectancy. for such species, even a small change in adult survival can strongly affect the population dynamics and viability. we examined the effects of both regional and local climatic variability on adult survival of the little auk, a long-lived and numerous arctic seabird species. we conducted a mark-resighting study for a period of 8 years (2006-2013) simultaneously at three little auk b ...201425247069
spatial ecotoxicology: migratory arctic seabirds are exposed to mercury contamination while overwintering in the northwest atlantic.arctic organisms are exposed to various levels of pollutants, among which mercury (hg) has raised important environmental concerns. previous studies examining hg levels, trends, and effects on arctic marine top predators have focused on the arctic region. however, many of these top predators, such as seabirds, migrate to spend a large part of their life cycle far from the arctic in areas where their exposure to contaminants is largely unknown. by combining biotelemetry and hg and stable isotope ...201425171766
different tactics, one goal: initial reproductive investments of males and females in a small arctic seabird.despite a great number of studies on extra-pair paternity in birds, the actual roles of males and females in extra-pair contacts is poorly understood, as detailed behavioural studies comparing the reproductive performance of the two sexes prior to egg laying are relatively scarce. here, we investigated mating behaviour (copulations and aggressive interactions), time budget and body condition (size-adjusted body mass and baseline corticosterone level) in the little auk (alle alle), a monogamous a ...201425152560
migration and opportunistic feeding increase pcb accumulation in arctic seabirds.it is widely accepted that body concentrations of persistent organic pollutants (pops) tend to increase with trophic level (tl). yet, little attention has been paid to the causes in the underlying differences in pop body concentrations between species occupying similar tls. in this paper we use two modeling approaches to quantify the importance of migration and opportunistic feeding, relative to that of trophic level, in explaining interspecific differences in polychlorinated biphenyl (pcb) body ...201324024972
behavioural and hormonal stress responses during chick rearing do not predict brood desertion by female in a small arctic seabird.we examined behavioural and hormonal stress responses in a small seabird (little auk, alle alle), which exhibits a transition from biparental to male-only care towards the end of the nesting period, in order to understand the mechanisms underlying this parental strategy. we hypothesized that the male staying with the chick should be less sensitive to stressors. as such the male might offer the offspring more efficient protection during the fledging period than the female. we tested this hypothes ...201323880555
biologging, remotely-sensed oceanography and the continuous plankton recorder reveal the environmental determinants of a seabird wintering hotspot.marine environments are greatly affected by climate change, and understanding how this perturbation affects marine vertebrates is a major issue. in this context, it is essential to identify the environmental drivers of animal distribution. here, we focused on the little auk (alle alle), one of the world's most numerous seabirds and a major component in arctic food webs. using a multidisciplinary approach, we show how little auks adopt specific migratory strategies and balance environmental const ...201222815967
adverse foraging conditions may impact body mass and survival of a high arctic seabird.tradeoffs between current reproduction and future survival are widely recognized, but may only occur when food is limited: when foraging conditions are favorable, parents may be able to reproduce without compromising their own survival. we investigated these tradeoffs in the little auk (alle alle), a small seabird with a single-egg clutch. during 2005-2007, we examined the relationship between body mass and survival of birds breeding under contrasting foraging conditions at two arctic colonies. ...201121445685
no evidence of blood parasites in little auks (alle alle) breeding on svalbard.absence of blood parasites in birds occurring in polar regions is believed to be a common phenomenon but only few surveys have been conducted on truly polar bird species. we examined blood parasites in a seabird with an exclusively high-arctic breeding distribution, the little auk (alle alle). polymerase chain reaction was used to detect haemosporidians and traditional optical microscopy was used to detect a wider range of haematozoans in birds breeding on svalbard (norway). no blood parasites w ...201020688653
the feeding ecology of little auks raises questions about winter zooplankton stocks in north atlantic surface waters.copepods are essential components of marine food webs worldwide. in the north atlantic, they are thought to perform vertical migration and to remain at depths more than 500 m during winter. we challenge this concept through a study of the winter feeding ecology of little auks (alle alle), a highly abundant planktivorous seabird from the north atlantic. by combining stable isotope and behavioural analyses, we strongly suggest that swarms of copepods are still available to their predators in water ...201020236962
effects of sheens associated with offshore oil and gas development on the feather microstructure of pelagic seabirds.operational discharges of hydrocarbons from maritime activities can have major cumulative impacts on marine ecosystems. small quantities of oil (i.e., 10 ml) results in often lethally reduced thermoregulation in seabirds. thin sheens of oil and drilling fluids form around offshore petroleum production structures from currently permissible operational discharges of hydrocarbons. methodology was developed to measure feather microstructure impacts (amalgamation index or ai) associated with sheen ex ...201020060137
comparing an estimate of seabirds at risk to a mortality estimate from the november 2004 terra nova fpso oil spill.on 21 november 2004, about 1000 barrels of crude oil were accidentally released from the terra nova fpso (floating production, storage and offloading) onto the grand banks, approximately 340 km east-southeast of st. john's, newfoundland. we estimated the number of vulnerable seabirds (murres (uria spp.) and dovekies (alle alle)) at risk from this incident by multiplying observed densities of seabirds with the total area covered by the slick, estimated at 793 km(2). a mean density of 3.46 murres/ ...200717328926
seabirds at risk around offshore oil platforms in the north-west atlantic.seabirds aggregate around oil drilling platforms and rigs in above average numbers due to night lighting, flaring, food and other visual cues. bird mortality has been documented due to impact on the structure, oiling and incineration by the flare. the environmental circumstances for offshore hydrocarbon development in north-west atlantic are unique because of the harsh climate, cold waters and because enormous seabird concentrations inhabit and move through the grand banks in autumn (storm-petre ...200111827114
[the finding of a cestode in the little auk alle alle on franz josef land].one of 14 dovekeys (alle alle) investigated in august 1993 on hooker island (franz joseph land) was found to harbour a single specimen of an early immature dilepidid cestode attributed as alcataenia sp. the rostellum bears a double crown of 22 hooks, 0.025-0.027 mm in length. except threlfall (1971) there was no information concerning dovekey's parasites.200710920847
phylogenetic relationships within the alcidae (charadriiformes: aves) inferred from total molecular evidence.the alcidae is a unique assemblage of northern hemisphere seabirds that forage by "flying" underwater. despite obvious affinities among the species, their evolutionary relationships are unclear. we analyzed nucleotide sequences of 1,045 base pairs of the mitochondrial cytochrome b gene and allelic profiles for 37 allozyme loci in all 22 extant species. trees were constructed on independent and combined data sets using maximum parsimony and distance methods that correct for superimposed changes. ...19968587501
stable isotopic determinations of trophic relationships of great auks.stable isotopic ratios of animal tissues are related to those of their foods and can be used in palaeoecological reconstructions, including those of extinct animals. nitrogen isotopic analyses of marine organisms from coastal newfoundland and georges bank were used to construct a model predicting collagen δ(15)n values for seabirds feeding at various trophic levels (tl). this model was tested by measuring bone collagen δ(15)n values of extant alcids from the northwest atlantic and high arctic. i ...199128313695
on the importance of fat reserves for the little auk (alle alle) chicks.the pattern of fat deposition and inter-year variation in the amount of deposited fat, lean dry mass (ldm) and water were studied in the chicks of little auk (alle alle), an arctic alcid, at spitsbergen in the 1984, 1986 and 1987 breeding seasons. the lipid index (lipid mass/ldm) rose from 0.29 at hatching to about 0.70 at the age of maximum body mass attained in the nest, the highest yet recorded for seabirds except procellariiforms. just before fledging the index dropped to 0.38. fat mass in 1 ...198928312653
on the crucial importance of a small bird: the ecosystem services of the little auk (alle alle) population in northwest greenland in a long-term perspective.the little auk is the most numerous seabird in the north atlantic and its most important breeding area is the eastern shores of the north water polynya. here, a population of an estimated 33 million pairs breeds in huge colonies and significantly shapes the ecosystem. archaeological remains in the colonies document that the little auk has been harvested over millennia. anthropological research discloses how the little auk has a role both as social engineer and as a significant resource for the i ...201829516440
egg patterns as identity signals in colonial seabirds: a comparison of four alcid species.the ability to recognize mates, kin, offspring and neighbors by their individually distinctive traits-individual recognition (ir)-is widespread in animals. much work has investigated ir from the perspective of the recognizer, but less is known about the extent to which signals have evolved to facilitate ir. to explore this, one approach is to compare putative identity signals among species that differ in life history and extent of ir. in common murres (uria aalge), a colonially breeding seabird, ...202032400035
contrasting spatial and seasonal trends of methylmercury exposure pathways of arctic seabirds: combination of large-scale tracking and stable isotopic approaches.despite the limited direct anthropogenic mercury (hg) inputs in the circumpolar arctic, elevated concentrations of methylmercury (mehg) are accumulated in arctic marine biota. however, the mehg production and bioaccumulation pathways in these ecosystems have not been completely unraveled. we measured hg concentrations and stable isotope ratios of hg, carbon, and nitrogen in the feathers and blood of geolocator-tracked little auk alle alle from five arctic breeding colonies. the wide-range spatia ...202033063513
exposure of a small arctic seabird, the little auk (alle alle) breeding in svalbard, to selected elements throughout the course of a year.the arctic marine ecosystem can be altered by processes of natural and anthropogenic origin. spatio-temporal variation in species exposure to contamination is still poorly understood. here, we studied elemental concentrations in the non-lethally collected samples from the most numerous seabird in european arctic, the little auk (alle alle) nesting in one breeding colony in svalbard. this seabird spent the breeding season in the high-arctic zone and the non-breeding period in sub-arctic areas wha ...202032428770
flexibility of little auks foraging in various oceanographic features in a changing arctic.using gps-tracked individuals, we compared foraging ecology and reproductive output of a high-arctic zooplanktivorous seabird, the little auk alle alle, between three years differing in environmental conditions (sea surface temperature). despite contrasting environmental conditions, average foraging fights distance and duration were generally similar in all studied years. also, in all years foraging locations visited by the little auk parents during short trips (st, for chick provisioning) were ...202032427941
climate change could overturn bird migration: transarctic flights and high-latitude residency in a sea ice free arctic.climate models predict that by 2050 the arctic ocean will be sea ice free each summer. removing this barrier between the atlantic and the pacific will modify a wide range of ecological processes, including bird migration. using published information, we identified 29 arctic-breeding seabird species, which currently migrate in the north atlantic and could shift to a transarctic migration towards the north pacific. we also identified 24 arctic-breeding seabird species which may shift from a migrat ...201931780706
determinants of the little auk (alle alle) breeding colony location and size in w and nw coast of spitsbergen.many seabirds breed in large aggregations, making it difficult to estimate their population size and habitat preferences. this knowledge is particularly important considering their function in food webs and ecosystem services. in this study, we investigated the factors affecting distribution and abundance of the little auk alle alle, a seabird considered a keystone species of the arctic ecosystem. we performed the study on the w and the nw coast of spitsbergen. using generalized additive models ...201930840697
arctic climate change and pollution impact little auk foraging and fitness across a decade.ongoing global changes apply drastic environmental forcing onto arctic marine ecosystems, particularly through ocean warming, sea-ice shrinkage and enhanced pollution. to test impacts on arctic marine ecological functioning, we used a 12-year integrative study of little auks (alle alle), the most abundant seabird in the atlantic arctic. we monitored the foraging ecology, reproduction, survival and body condition of breeding birds, and we tested linkages between these biological variables and a s ...201930705325
bird population changes reconstructed from isotopic signals of peat developed in a nutrient enriched tundra.five peat sequences were studied to identify the time the little auk alle alle colonies originated in the hornsund area (spitsbergen). elemental and stable isotope analysis of nitrogen and carbon was applied as markers for bird activity. the peat sequences were dated with 210pb and radiocarbon methods. the results showed that peat development related to seabird activity is significantly older (at least 300 years old) in localities closer to the fjord's mouth (west) than those located deeper in t ...201930235621
sex- and breeding stage-specific hormonal stress response of seabird parents.changes in corticosterone (cort) and prolactin (prl) levels are thought to provide complementary information on parental decisions in birds in the context of stressful situations. however, these endocrine mechanisms have yet to be fully elucidated, appearing to vary among avian species without any clear pattern. here, we examined cort and prl stress responses in a small arctic seabird, the little auk (alle alle). we analysed the levels of these hormones (baseline, and stress response, i.e. the c ...201829928891
almost like a whale - first evidence of suction feeding in a seabird.little auks (alle alle) are one of the most numerous seabird species in the world and feed primarily on copepods in arctic waters. their high daily energy requirements leave them vulnerable to current changes in the arctic plankton community, where a smaller, less-profitable copepod species (calanus finmarchicus) becomes increasingly abundant. little auks have been estimated to require ∼60,000 copepods per day, necessitating prey capture rates of ∼6 copepods per second underwater. to achieve suc ...201829844199
the history of seabird colonies and the north water ecosystem: contributions from palaeoecological and archaeological evidence.the north water (now) polynya is one of the most productive marine areas of the arctic and an important breeding area for millions of seabirds. there is, however, little information on the dynamics of the polynya or the bird populations over the long term. here, we used sediment archives from a lake and peat deposits along the greenland coast of the now polynya to track long-term patterns in the dynamics of the seabird populations. radiocarbon dates show that the thick-billed murre (uria lomvia) ...201829516438
energyscapes and prey fields shape a north atlantic seabird wintering hotspot under climate change.there is an urgent need for a better understanding of animal migratory ecology under the influence of climate change. most current analyses require long-term monitoring of populations on the move, and shorter-term approaches are needed. here, we analysed the ecological drivers of seabird migration within the framework of the energyscape concept, which we defined as the variations in the energy requirements of an organism across geographical space as a function of environmental conditions. we com ...201829410875
seabird parents provision their chick in a coordinated manner.pair collaborative behavior may play an important role in avian reproduction. however, evidence for this mainly comes from certain ecological groups (e.g. passerines). we studied the coordination of parents in foraging and its effect on food provisioning rate and chick growth in a small seabird, the dovekie (little auk, alle alle). the species exhibits a dual foraging strategy, where provisioning adults make foraging trips of short (mean ~2 h; to provide food for the chick) and long duration (me ...201829320525
habitat foraging niche of a high arctic zooplanktivorous seabird in a changing environment.here, we model current and future distribution of a foraging arctic endemic species, the little auk (alle alle), a small zooplanktivorous arctic seabird. we characterized environmental conditions [sea depth, sea surface temperature (sst), marginal sea ice zone (miz)] at foraging positions of gps-tracked individuals from three breeding colonies in svalbard: one located at the southern rim of the arctic zone (hereafter 'boreo-arctic') and two in the high-arctic zone on spitsbergen ('high-arctic'). ...201729176574
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