Publications

TitleAbstractYear(sorted descending)
Filter
PMID
Filter
health surveillance of penguins in the barton peninsula on king george island, antarctica.samples from 29 adult gentoo (pygoscelis papua), chinstrap (pygoscelis antarcticus), and adélie penguins (pygoscelis adeliae) at the king sejong station on nar̢ ebski point, king george island, antarctica, were investigated to detect antibodies to avian influenza, newcastle disease virus, infectious bursal disease virus, infectious bronchitis virus, mycoplasma, and salmonella. antibodies were identified from one gentoo penguin and one chinstrap penguin against infectious bronchitis virus; from o ...202133872350
avian orthoavulavirus 1 (newcastle disease virus) antibodies in five penguin species, antarctic peninsula and southern patagonia.avian orthoavulavirus 1 (aoav-1) causes newcastle disease, one of the most important and contagious infections in poultry, where migratory birds can play a key role as a reservoir. seven hundred and seven serum samples were collected from five penguin species (king, magellanic, gentoo, chinstrap and adelie penguins) in the antarctic and sub-antarctic zones. using a competitive elisa to detect antibodies against aoav-1, we identified positive individuals in all penguin species. the magellanic pen ...202133587778
latitudinal, sex and inter-specific differences in mercury and other trace metal concentrations in adélie and emperor penguins in the ross sea, antarctica.we sought to determine mercury (hg) and other trace metal concentrations in adélie (pygoscelis adeliae) and emperor penguin (aptenodytes forsteri) breast feathers from the ross sea, antarctica, and relate those concentrations to the trophic position and the habitats in which each of these species forage. adélie penguin feathers from the southern ross sea colonies were higher in hg than those sampled further north in the ross sea, potentially due to greater exposure to local sources, such as volc ...202032319892
counting penguins with drones.a multidrone path-planning algorithm enables drones to scout adélie penguin colonies in antarctica.202033115885
multidrone aerial surveys of penguin colonies in antarctica.speed is essential in wildlife surveys due to the dynamic movement of animals throughout their environment and potentially extreme changes in weather. in this work, we present a multirobot path-planning method for conducting aerial surveys over large areas designed to make the best use of limited flight time. unlike current survey path-planning solutions based on geometric patterns or integer programs, we solve a series of satisfiability modulo theory instances of increasing complexity. each ins ...202033115884
antarctic adélie penguin feathers as bio-indicators of geographic and temporal variations in heavy metal concentrations in their habitats.seabird feathers are effective indicators of heavy metal contamination. to propose a biological detection method suitable for the long-term monitoring of heavy metals in the antarctic environment, eight heavy metals (as, cd, cr, cu, hg, ni, pb, and zn) in adélie penguin feathers from different body parts, years, and molting grounds in the antarctic were investigated in this study. it is found that the concentrations of heavy metals in the feathers showed differences among the body part of origin ...202032866890
foraging behavior links sea ice to breeding success in antarctic penguins.population trends and breeding success variability of adélie penguins, a bioindicator of antarctic environments, have been attributed to changing sea-ice extents; however, causative mechanisms remain unclear. by electronically tagging 175 penguins in four seasons with contrasting sea-ice conditions, we show that ice-free environments enhance, not deteriorate, foraging efficiencies and breeding success. in an ice-free season, penguins traveled by swimming rather than walking, leading to larger fo ...202032637612
drivers of concentrated predation in an antarctic marginal-ice-zone food web.predators impact preyscapes (3-d distribution of forage species) by consuming prey according to their abilities or by altering prey behavior as they avoid being consumed. we elucidate prey (antarctic silverfish[pleuragramma antarctica] and crystal krill[euphausia chrystallorophias]) responses to predation associated with the marginal ice zone (miz) of the mcmurdo sound, antarctica, polynya. prey abundance and habitat was sampled across a 30 × 15 km area by remotely-operated vehicle, and included ...202032350362
sea ice predicts long-term trends in adélie penguin population growth, but not annual fluctuations: results from a range-wide multiscale analysis.understanding the scales at which environmental variability affects populations is critical for projecting population dynamics and species distributions in rapidly changing environments. here we used a multilevel bayesian analysis of range-wide survey data for adélie penguins to characterize multidecadal and annual effects of sea ice on population growth. we found that mean sea ice concentration at breeding colonies (i.e., "prevailing" environmental conditions) had robust nonlinear effects on mu ...202032190944
density dependence forces divergent population growth rates and alters occupancy patterns of a central place foraging antarctic seabird.density-dependent regulation is an important process in spatio-temporal population dynamics because it can alter the effects of synchronizing processes operating over large spatial scales. most frequently, populations are regulated by density dependence when higher density leads to reduced individual fitness and population growth, but inverse density dependence can also occur when small populations are subject to higher extinction risks. we investigate whether density-dependent regulation influe ...202032184985
adélie penguin colonies as indicators of brominated flame retardants (bfrs) in east antarctica.while persistent organic pollutant (pop) contamination within antarctica is largely caused by long-range atmospheric transport (lrat), antarctic research bases have been shown to be local sources of pops such as brominated flame retardants (bfrs). this study compared concentrations of seven polybrominated diphenyl ethers (pbde) congeners and five novel flame retardants (nbfrs) found in adélie penguin (pygoscelis adeliae) colony soils near the australian research stations, mawson and davis, to as ...202032126331
a smelly business: microbiology of adélie penguin guano (point thomas rookery, antarctica).adélie penguins (pygoscelis adeliae) are the most numerous flightless bird group breeding in coastal areas of maritime and continental antarctica. their activity leaves a mark on the land in the form of large guano deposits. this guano is an important nutrient source for terrestrial habitats of ice-free antarctic areas, most notably by being the source of ammonia vapors which feed the surrounding grass, lichen and algae communities. although investigated by researchers, the fate of the guano-ass ...202031978775
application of δ15n to trace the impact of penguin guano on terrestrial and aquatic nitrogen cycles in victoria land, ross sea region, antarctica.penguin colonies in antarctica offer an ideal "natural laboratory" to investigate ecosystem function and the nitrogen (n) cycle. this study assessed the spatial distribution of penguin-derived n from guano and quantitatively assessed its impact on plant n utilization strategies in victoria land, ross sea region, antarctica. soil, moss, and aquatic microbial mats were collected inside and outside an active adélie penguin (pygoscelis adeliae) colony and analyzed for δ15n of total and inorganic nit ...202031874340
genetic factors for short life span associated with evolution of the loss of flight ability.acquisition or loss of flying ability is evolutionarily linked with maximum life span (mls) in mammals and birds. although ecological factors, such as extrinsic mortality, may lead to either shortened or extended life spans through natural selection, mls is influenced by complex molecular and metabolic processes, and the genetic changes associated with flying ability that have led to either a longer or shorter mls are unknown. here, we examine the parallel evolution of flight in mammals and bird ...202032607209
characterization of staphylococcus intermedius group isolates associated with animals from antarctica and emended description of staphylococcus delphini.members of the genus staphylococcus are widespread in nature and occupy a variety of niches, however, staphylococcal colonization of animals in the antarctic environment has not been adequately studied. here, we describe the first isolation and characterization of two staphylococcus intermedius group (sig) members, staphylococcus delphini and staphylococcus pseudintermedius, in antarctic wildlife. staphylococcus delphini were found exclusively in adélie penguins. the report of s. pseudintermediu ...202032024111
anthropogenic radionuclides in antarctic biota - dosimetrical considerations.the article presents results of the research on artificial radionuclides (137cs, 90sr, 241am) in the antarctic environment. samples of 12 species from the marine environment: pygoscelis adeliae, pygoscelis papua, macronectes giganteus, pagodroma nivea, catharacta antarctica, leptonychotes weddellii, mirounga leonina, harpagifer antarcticus, chaenocephalus aceratus, nacella concinna, himantothallus grandifolius, iridaea cordata (bones, feathers, soft tissues, eggs' shells of birds, bones, skin, f ...202031983449
identification and distribution of novel cressdnaviruses and circular molecules in four penguin species in south georgia and the antarctic peninsula.there is growing interest in uncovering the viral diversity present in wild animal species. the remote antarctic region is home to a wealth of uncovered microbial diversity, some of which is associated with its megafauna, including penguin species, the dominant avian biota. penguins interface with a number of other biota in their roles as marine mesopredators and several species overlap in their ranges and habitats. to characterize the circular single-stranded viruses related to those in the phy ...202032947826
identification of circovirus genome in a chinstrap penguin (pygoscelis antarcticus) and adélie penguin (pygoscelis adeliae) on the antarctic peninsula.circoviruses infect a variety of animal species and have small (~1.8-2.2 kb) circular single-stranded dna genomes. recently a penguin circovirus (pencv) was identified associated with an adélie penguin (pygoscelis adeliae) with feather disorder and in the cloacal swabs of three asymptomatic adélie penguins at cape crozier, antarctica. a total of 75 cloacal swab samples obtained from adults and chicks of three species of penguin (genus: pygoscelis) from seven antarctic breeding colonies (south sh ...202032781620
biological factors affecting total mercury and methylmercury levels in antarctic penguins.penguins in antarctica occupy high trophic levels, thus accumulating high amounts of mercury (hg) through bioaccumulation and biomagnification. blood reflects the current levels of contaminants circulating in the body, while feathers are known as the main route of hg elimination in birds. studies sampling chicks and adults can provide a comprehensive picture of bioaccumulation and local contamination. three pygoscelid species (pygoscelis adeliae, pygoscelis antarcticus and pygoscelis papua) have ...202032738710
pingu virus: a new picornavirus in penguins from antarctica.picornaviridae family comprises single-stranded, positive-sense rna viruses distributed into forty-seven genera. picornaviruses have a broad host range and geographic distribution in all continents. in this study, we applied a high-throughput sequencing approach to examine the presence of picornaviruses in penguins from king george island, antarctica. we discovered and characterized a novel picornavirus from cloacal swab samples of gentoo penguins (pygoscelis papua), which we tentatively named p ...201931850147
antarctic penguins as reservoirs of diversity for avian avulaviruses.wild birds harbor a huge diversity of avian avulaviruses (formerly avian paramyxoviruses). antarctic penguin species have been screened for avian avulaviruses since the 1980s and, as such, are known hosts of these viruses. in this study, we screened three penguin species from the south shetland islands and the antarctic peninsula for avian avulaviruses. we show that adelie penguins (pygoscelis adeliae) are hosts for four different avian avulavirus species, the recently described avian avulavirus ...201930894472
nonbreeder birds at colonies display qualitatively similar seasonal mass change patterns as breeders.the difficulty in studying nonbreeding birds means that little is known about them or their resource requirements, despite forming a large and significant component of a population. one way to assess food requirements is to examine changes in body mass, because it indicates the amount of food acquired. in terms of body mass changes, our expectation is that nonbreeders will either (a) be in poorer condition than the breeders which potentially explains why they do not breed or (b) remain at a stab ...201931031932
evidence of age-related improvement in the foraging efficiency of adélie penguins.age variation in reproductive performance is well-documented but the mechanisms underlying this variation remain unclear. foraging efficiency is likely to be a key source of demographic variation as it determines the amount of energy that can be invested in fitness-related activities. evidence of age-related changes in the foraging efficiency of adult seabirds is scarce and inconsistent. we investigated the effects of age on the foraging efficiency of breeding adélie penguins, a relatively short ...201930833598
central place foragers select ocean surface convergent features despite differing foraging strategies.discovering the predictors of foraging locations can be challenging, and is often the critical missing piece for interpreting the ecological significance of observed movement patterns of predators. this is especially true in dynamic coastal marine systems, where planktonic food resources are diffuse and must be either physically or biologically concentrated to support upper trophic levels. in the western antarctic peninsula, recent climate change has created new foraging sympatry between adélie ...201930655549
novel penguin avian avulaviruses 17, 18 and 19 are widely distributed in the antarctic peninsula.three novel avian avulavirus species were discovered and isolated during 2017 from gentoo penguins (pygoscelis papua) at kopaitic island in the northwestern region of the antarctic peninsula. the viruses were officially named as avian avulavirus 17 (aav17), avian avulavirus 18 (aav18) and avian avulavirus 19 (aav19), collectively referred to as penguin avulaviruses (pavs). to determine whether these viruses are capable of infecting the three species of pygoscelis spp. penguins (gentoo, adelie an ...201931355981
identification of a novel adélie penguin circovirus at cape crozier (ross island, antarctica).understanding the causes of disease in antarctic wildlife is crucial, as many of these species are already threatened by environmental changes brought about by climate change. in recent years, antarctic penguins have been showing signs of an unknown pathology: a feather disorder characterised by missing feathers, resulting in exposed skin. during the 2018-2019 austral summer breeding season at cape crozier colony on ross island, antarctica, we observed for the first time an adélie penguin chick ...201931766719
penguin megrivirus, a novel picornavirus from an adélie penguin (pygoscelis adeliae).the complete genome sequence of a novel megrivirus of the family picornaviridae was determined from nucleic acid extracted from a pool of six faecal specimens of adélie penguins. the samples were collected near bellingshausen station, king george island of the south shetland islands, antarctica. penguin megrivirus is the first megrivirus with a predicted l protein. it has an l-3-5-4 genome layout, a type iv ires, and a long 3' untranslated region of 668 nt.201931494778
the interaction between island geomorphology and environmental parameters drives adélie penguin breeding phenology on neighboring islands near palmer station, antarctica.despite many studies on adélie penguin breeding phenology, understanding the drivers of clutch initiation dates (cids, egg 1 lay date) is limited or lacks consensus. here, we investigated adélie penguin cids over 25 years (1991-2016) on two neighboring islands, torgersen and humble (<1 km apart), in a rapidly warming region near palmer station, antarctica. we found that sea ice was the primary large-scale driver of cids and precipitation was a secondary small-scale driver that fine-tunes cid to ...201931463025
when the "selfish herd" becomes the "frozen herd": spatial dynamics and population persistence in a colonial seabird.aggregations are common in ecological systems at a range of scales and may be driven by exogenous constraints such as environmental heterogeneity and resource availability or by "self-organizing" interactions among individuals. one mechanism leading to self-organized animal aggregations is captured by hamilton's "selfish herd" hypothesis, which suggests that aggregations may be driven by an individual's effort to minimize their risk of predation by surrounding themselves with conspecifics. we de ...201931310664
population response of an apex antarctic consumer to its prey and climate fluctuations.a fundamental endeavor in population ecology is to identify the drivers of population dynamics. a few empirical studies included the effect of prey abundance when investigating simultaneously the effects of density-dependence and climate factors on marine top-predator population dynamics. our aim was to unravel the mechanisms forcing population dynamics of an apex consumer seabird, the south polar skua, using long-term climatic and population time series of the consumer and its prey in terre adé ...201930116877
nasal mites (mesostigmata: rhinonyssidae) in african penguins (spheniscus demersus).rhinonyssids are obligate haematophagous mites that parasitize the nasal cavity of vertebrates, and occur in a wide range of birds worldwide. two species of nasal mites are known to occur in penguins: rhinonyssus sphenisci, which has been recorded from humboldt and magellanic penguins (spheniscus humboldti and s. magellanicus, respectively), and rhinonyssus schelli, which has been recorded in adélie and gentoo penguins (pygoscelis adeliae and p. papua, respectively). we examined the nasal cavity ...201929921335
the rise and fall of an ancient adélie penguin 'supercolony' at cape adare, antarctica.we report new discoveries and radiocarbon dates on active and abandoned adélie penguin (pygoscelis adeliae) colonies at cape adare, antarctica. this colony, first established at approximately 2000 bp (calendar years before present, i.e. 1950), is currently the largest for this species with approximately 338 000 breeding pairs, most located on low-lying ridley beach. we hypothesize that this colony first formed after fast ice began blocking open-water access by breeding penguins to the scott coas ...201829765656
influence of biological factors on hematological and serum biochemistry values in captive adélie, chinstrap, gentoo, and macaroni penguins in pingtung, taiwan.hematology and serum biochemistry reference values are essential for health evaluation and disease diagnosis in penguins. however, there are currently no published physiological values for captive adélie (pygoscelis adeliae) and chinstrap penguins (p. antarcticus), nor for wild or captive macaroni penguins (eudyptes chrysolophus). the present study is the first investigation regarding hematology and serum biochemistry reference values for captive adélie, gentoo (p. papua), chinstrap, and macaron ...201829722905
time-lapse imagery of adélie penguins reveals differential winter strategies and breeding site occupation.polar seabirds adopt different over-wintering strategies to survive and build condition during the critical winter period. penguin species either reside at the colony during the winter months or migrate long distances. tracking studies and survey methods have revealed differences in winter migration routes among penguin species and colonies, dependent on both biotic and abiotic factors present. however, scan sampling methods are rarely used to reveal non-breeding behaviors during winter and litt ...201829561876
temporal variation in trophic relationships among three congeneric penguin species breeding in sympatry.penguins are a monophyletic group in which many species are found breeding sympatrically, raising questions regarding how these species coexist successfully. here, the isotopic niche of three sympatric pygoscelid penguin species was investigated at powell island, south orkney islands, during two breeding seasons (austral summers 2013-2014 and 2015-2016). measurements of carbon (δ13c) and nitrogen (δ15n) stable isotope ratios were obtained from blood (adults) or feather (chicks) samples collected ...201829686847
multi-modal survey of adélie penguin mega-colonies reveals the danger islands as a seabird hotspot.despite concerted international effort to track and interpret shifts in the abundance and distribution of adélie penguins, large populations continue to be identified. here we report on a major hotspot of adélie penguin abundance identified in the danger islands off the northern tip of the antarctic peninsula (ap). we present the first complete census of pygoscelis spp. penguins in the danger islands, estimated from a multi-modal survey consisting of direct ground counts and computer-automated c ...201829500389
reproductive performance and diving behaviour share a common sea-ice concentration optimum in adélie penguins (pygoscelis adeliae).the southern ocean is currently experiencing major environmental changes, including in sea-ice cover. such changes strongly influence ecosystem structure and functioning and affect the survival and reproduction of predators such as seabirds. these effects are likely mediated by reduced availability of food resources. as such, seabirds are reliable eco-indicators of environmental conditions in the antarctic region. here, based on 9 years of sea-ice data, we found that the breeding success of adél ...201829957836
spatial niche partitioning may promote coexistence of pygoscelis penguins as climate-induced sympatry occurs.climate-induced range overlap can result in novel interactions between similar species and potentially lead to competitive exclusion. the west antarctic peninsula (wap) is one of the most rapidly warming regions on earth and is experiencing a poleward climate migration from a polar to subpolar environment. this has resulted in a range expansion of the ice-intolerant gentoo penguins (pygoscelis papua) and a coincident decrease in ice-obligate adélie penguins (p. adeliae) near palmer station, anve ...201830386573
comparative population genomics reveals key barriers to dispersal in southern ocean penguins.the mechanisms that determine patterns of species dispersal are important factors in the production and maintenance of biodiversity. understanding these mechanisms helps to forecast the responses of species to environmental change. here, we used a comparative framework and genomewide data obtained through rad-seq to compare the patterns of connectivity among breeding colonies for five penguin species with shared ancestry, overlapping distributions and differing ecological niches, allowing an exa ...201830308702
genomic insights into natural selection in the common loon (gavia immer): evidence for aquatic adaptation.the common loon (gavia immer) is one of five species that comprise the avian order gaviiformes. loons are specialized divers, reaching depths up to 60 m while staying submerged for intervals up to three minutes. in this study we used comparative genomics to investigate the genetic basis of the common loon adaptations to its ecological niche. we used illumina short read dna sequence data from a female bird to produce a draft assembly of the common loon (gavia immer) genome.201829703132
landscape genomics: natural selection drives the evolution of mitogenome in penguins.mitochondria play a key role in the balance of energy and heat production, and therefore the mitochondrial genome is under natural selection by environmental temperature and food availability, since starvation can generate more efficient coupling of energy production. however, selection over mitochondrial dna (mtdna) genes has usually been evaluated at the population level. we sequenced by ngs 12 mitogenomes and with four published genomes, assessed genetic variation in ten penguin species distr ...201829338715
aerial photography based census of adélie penguin and its application in ch4 and n2o budget estimation in victoria land, antarctic.penguin guano provides favorable conditions for production and emission of greenhouse gases (ghgs). many studies have been conducted to determine the ghg fluxes from penguin colonies, however, at regional scale, there is still no accurate estimation of total ghg emissions. we used object-based image analysis (obia) method to estimate the adélie penguin (pygoscelis adeliae) population based on aerial photography data. a model was developed to estimate total ghg emission potential from adélie peng ...201729021539
unique genome organization of non-mammalian papillomaviruses provides insights into the evolution of viral early proteins.the familypapillomaviridaecontains more than 320 papillomavirus types, with most having been identified as infecting skin and mucosal epithelium in mammalian hosts. to date, only nine non-mammalian papillomaviruses have been described from birds (n = 5), a fish (n = 1), a snake (n = 1), and turtles (n = 2). the identification of papillomaviruses in sauropsids and a sparid fish suggests that early ancestors of papillomaviruses were already infecting the earliest euteleostomi. the euteleostomi cla ...201729026649
rethinking "normal": the role of stochasticity in the phenology of a synchronously breeding seabird.phenological changes have been observed in a variety of systems over the past century. there is concern that, as a consequence, ecological interactions are becoming increasingly mismatched in time, with negative consequences for ecological function. significant spatial heterogeneity (inter-site) and temporal variability (inter-annual) can make it difficult to separate intrinsic, extrinsic and stochastic drivers of phenological variability. the goal of this study was to understand the timing and ...201729277890
pan-antarctic analysis aggregating spatial estimates of adélie penguin abundance reveals robust dynamics despite stochastic noise.colonially-breeding seabirds have long served as indicator species for the health of the oceans on which they depend. abundance and breeding data are repeatedly collected at fixed study sites in the hopes that changes in abundance and productivity may be useful for adaptive management of marine resources, but their suitability for this purpose is often unknown. to address this, we fit a bayesian population dynamics model that includes process and observation error to all known adélie penguin abu ...201729018199
isolation of campylobacter spp. from three species of antarctic penguins in different geographic locations.the presence of campylobacter species was studied in three antarctic penguin species, adélie (pygoscelis adeliae), chinstrap (pygoscelis antarctica) and gentoo (pygoscelis papua). a total of 390 penguins were captured in 12 different rookeries along the antarctic peninsula with differences in the amount of human visitation: six colonies were highly visited [stranger point, king george island (p. papua and p. adeliae); hannah point, livingston island (p. papua and p. antarctica); deception island ...201728091764
identification of a polyomavirus in weddell seal (leptonychotes weddellii) from the ross sea (antarctica).viruses are ubiquitous in nature, however, very few have been identified that are associated with antarctic animals. here we report the identification of a polyomavirus in the kidney tissue of a deceased weddell seal from the ross sea, antarctica. the circular genome (5186 nt) has typical features of polyomaviruses with a small and larger t-antigen open reading frames (orfs) and three orfs encoding vp1, vp2 and vp3 capsid proteins. the genome of the weddell seal polyomavirus (wspyv) shares 85.4% ...201728124141
legacy persistent organic pollutants including pbdes in the trophic web of the ross sea (antarctica).the ecological features of the ross sea trophic web are peculiar and different from other polar food webs, with respect to the use of habitat and species interactions; due to its ecosystem integrity, it is the world's largest marine protected area, established in 2016. polar organisms are reported to bioaccumulate lipophilic contaminant, viz persistent organic pollutants (pops). legacy pops and flame retardants (polybrominated diphenyl ethers, pbdes) were studied in key species of the ross sea ( ...201728732330
reproductive effort affects oxidative status and stress in an antarctic penguin species: an experimental study.the oxidative cost of reproduction has been a matter of debate in recent years presumably because of the lack of proper experimental studies. based on the hypothesis that different brood sizes produce differential reproductive costs, an experimental manipulation during breeding of adélie penguins was conducted at hope bay, antarctica, to study oxidative status and stress. we predict that a lower reproductive effort should be positively related to low oxidative and physiological stress. we random ...201728493935
socially-induced variation in physiological mediators of parental care in a colonial bird.social facilitation of reproduction occurs in humans and animals, and may represent one of the bases of reproduction in groups. however, its underlying physiological mechanisms remain largely unexplored. here, we found in a colonial bird, the adélie penguin (pygoscelis adeliae), that the number of parental interactions (nest relief ceremonies) performed by breeding individuals on the colony was positively related to prolactin levels in other breeding individuals exposed to these interactions (i. ...201728356224
a comparative assessment of fatty acids in antarctic organisms from the ross sea: occurrence and distribution.lipids are important energy source and structural component for cellular membranes and tissues, involved in the osmoregulation and immune response, and are very important in the bioaccumulation of lipophilic chemicals too. among lipids, fatty acids (fas) give information on diet of organisms, since fa of consumer lipids can be related to those of diet; plants and animals vary in their fa signature because of differences in the synthesis of lipids. in this study, lipid content and fa composition ...201728237525
circumpolar analysis of the adélie penguin reveals the importance of environmental variability in phenological mismatch.evidence of climate-change-driven shifts in plant and animal phenology have raised concerns that certain trophic interactions may be increasingly mismatched in time, resulting in declines in reproductive success. given the constraints imposed by extreme seasonality at high latitudes and the rapid shifts in phenology seen in the arctic, we would also expect antarctic species to be highly vulnerable to climate-change-driven phenological mismatches with their environment. however, few studies have ...201728129431
the influence of historical climate changes on southern ocean marine predator populations: a comparative analysis.the southern ocean ecosystem is undergoing rapid physical and biological changes that are likely to have profound implications for higher-order predators. here, we compare the long-term, historical responses of southern ocean predators to climate change. we examine palaeoecological evidence for changes in the abundance and distribution of seabirds and marine mammals, and place these into context with palaeoclimate records in order to identify key environmental drivers associated with population ...201626391440
climate-driven sympatry may not lead to foraging competition between congeneric top-predators.climate-driven sympatry may lead to competition for food resources between species. rapid warming in the west antarctic peninsula (wap) is coincident with increasing gentoo penguin and decreasing adélie penguin populations, suggesting that competition for food may exacerbate the adélie penguin decline. on fine scales, we tested for foraging competition between these species during the chick-rearing period by comparing their foraging behaviors with the distribution of their prey, antarctic krill. ...201626732496
sex-based differences in adélie penguin (pygoscelis adeliae) chick growth rates and diet.sexually size-dimorphic species must show some difference between the sexes in growth rate and/or length of growing period. such differences in growth parameters can cause the sexes to be impacted by environmental variability in different ways, and understanding these differences allows a better understanding of patterns in productivity between individuals and populations. we investigated differences in growth rate and diet between male and female adélie penguin (pygoscelis adeliae) chicks durin ...201626934698
simultaneous dna-based diet analysis of breeding, non-breeding and chick adélie penguins.as central place foragers, breeding penguins are restricted in foraging range by the need to return to the colony to feed chicks. furthermore, breeding birds must balance energetic gain from self-feeding with the costs of returning to provision young. non-breeding birds, however, are likely to be less restricted in foraging range and lack the high energy demands of provisioning, therefore may consume different prey to breeders. we used dna dietary analysis to determine whether there was a differ ...201626909171
correction: spatially extensive standardized surveys reveal widespread, multi-decadal increase in east antarctic adélie penguin populations.[this corrects the article doi: 10.1371/journal.pone.0139877.].201627792768
population size and decadal trends of three penguin species nesting at signy island, south orkney islands.we report long-term changes in population size of three species of sympatrically breeding pygoscelid penguins: adélie (pygoscelis adeliae), chinstrap (pygoscelis antarctica) and gentoo (pygoscelis papua ellsworthii) over a 38 year period at signy island, south orkney islands, based on annual counts from selected colonies and decadal all-island systematic counts of occupied nests. comparing total numbers of breeding pairs over the whole island from 1978/79 to 2015/16 revealed varying fortunes: ge ...201627783668
persistent organic pollutants and porphyrins biomarkers in penguin faeces from kopaitic island and antarctic peninsula.polychlorinated biphenyl (pcb) levels were determined in the faeces of three antarctic peninsula penguin species to assess viability as a non-invasive approach for sampling pcbs in antarctic biota. these determinations were complemented with stable isotope and porphyrins assessments, and together this methodology determined the role of diet and metabolic disruption in penguins. up to 60% of the collected faecal samples evidenced low molecular weight pcbs, of which, the more volatile compounds we ...201627450255
persistent organic pollutants in the antarctic coastal environment and their bioaccumulation in penguins.persistent organic pollutants (pops), including polychlorinated dibenzo-p-dioxins and dibenzofurans (pcdd/fs), polychlorinated biphenyls (pcbs), polybrominated dibenzo-p-dioxins and dibenzofurans (pbdd/fs), polybrominated biphenyls (pbbs), and polybrominated diphenyl ethers (pbdes), have been identified in penguins, lichens, soils, and ornithogenic soils in the antarctic coastal environment in this study. to the best of our knowledge, no previous study has reported pbdd/f and pbb data from antar ...201627400905
projected asymmetric response of adélie penguins to antarctic climate change.the contribution of climate change to shifts in a species' geographic distribution is a critical and often unresolved ecological question. climate change in antarctica is asymmetric, with cooling in parts of the continent and warming along the west antarctic peninsula (wap). the adélie penguin (pygoscelis adeliae) is a circumpolar meso-predator exposed to the full range of antarctic climate and is undergoing dramatic population shifts coincident with climate change. we used true presence-absence ...201627352849
mode of attachment and pathology caused by parorchites zederi in three species of penguins: pygoscelis papua, pygoscelis adeliae, and pygoscelis antarctica in antarctica.we identified and compared gross and microscopic lesions associated with the cestode, parorchites zederi, in the digestive tracts of three species of penguins (spheniscidae): the chinstrap ( pygoscelis antarctica ), gentoo ( pygoscelis papua ), and adélie penguins ( pygoscelis adeliae ). the gastrointestinal tracts of 79 recently dead individuals (71 chicks and eight adults) were collected in locations throughout the antarctic peninsula during summer field trips in 2006-09. parorchites zederi wa ...201627195682
evidence for the introduction, reassortment, and persistence of diverse influenza a viruses in antarctica.avian influenza virus (aiv) surveillance in antarctica during 2013 revealed the prevalence of evolutionarily distinct influenza viruses of the h11n2 subtype in adélie penguins. here we present results from the continued surveillance of aiv on the antarctic peninsula during 2014 and 2015. in addition to the continued detection of h11 subtype viruses in a snowy sheathbill during 2014, we isolated a novel h5n5 subtype virus from a chinstrap penguin during 2015. gene sequencing and phylogenetic anal ...201627535050
persistent organic pollutants and polycyclic aromatic hydrocarbons in penguins of the genus pygoscelis in admiralty bay - an antarctic specially managed area.persistent organic pollutants were assessed in fat samples of the gentoo (pygoscelis papua), chinstrap (pygoscelis antarcticus) and adélie (pygoscelis adeliae) penguins collected during the austral summers of 2005/06 and 2006/07 in admiralty bay, king george island, antarctica. the predominant organic pollutants were pcb (114 to 1115), polycyclic aromatic hydrocarbons (pahs) (60.1 to 238.7), hcb (<0.3 to 132.2) and bde-47 (<1.0 to 10.7) in ng g(-1) wet weight. the mean concentrations of the majo ...201626952994
first record of babesia sp. in antarctic penguins.this is the first reported case of babesia sp. in antarctic penguins, specifically a population of chinstrap penguins (pygoscelis antarctica) in the vapour col penguin rookery in deception island, south shetlands, antarctica. we collected peripheral blood from 50 adult and 30 chick chinstrap penguins. examination of the samples by microscopy showed intraerythrocytic forms morphologically similar to other avian babesia species in 12 chinstrap penguin adults and seven chicks. the estimated parasit ...201626874670
penguin lungs and air sacs: implications for baroprotection, oxygen stores and buoyancy.the anatomy and volume of the penguin respiratory system contribute significantly to pulmonary baroprotection, the body o2 store, buoyancy and hence the overall diving physiology of penguins. therefore, three-dimensional reconstructions from computerized tomographic (ct) scans of live penguins were utilized to measure lung volumes, air sac volumes, tracheobronchial volumes and total body volumes at different inflation pressures in three species with different dive capacities [adélie (pygoscelis ...201525740902
identification of an avian polyomavirus associated with adélie penguins (pygoscelis adeliae).little is known about viruses associated with antarctic animals, although they are probably widespread. we recovered a novel polyomavirus from adélie penguin (pygoscelis adeliae) faecal matter sampled in a subcolony at cape royds, ross island, antarctica. the 4988 nt adélie penguin polyomavirus (adpyv) has a typical polyomavirus genome organization with three orfs that encoded capsid proteins on the one strand and two non-structural protein-coding orfs on the complementary strand. the genome of ...201525537375
occurrence of legacy and new persistent organic pollutants in avian tissues from king george island, antarctica.legacy and new persistent organic pollutants (pops), including polychlorinated naphthalenes (pcns), dechlorane plus (dps) and related compounds (dechloranes), hexabromocyclododecanes (hbcds), polychlorinated biphenyls (pcbs), and organochlorine pesticides (ocps), were analyzed in avian tissue samples from king george island, antarctica. the avian species consisted of the gentoo penguin (pygoscelis papua), the adelie penguin (pygoscelis adeliae), the south polar skua (stercorarius maccormicki), a ...201526502059
spatially extensive standardized surveys reveal widespread, multi-decadal increase in east antarctic adélie penguin populations.seabirds are considered to be useful and practical indicators of the state of marine ecosystems because they integrate across changes in the lower trophic levels and the physical environment. signals from this key group of species can indicate broad scale impacts or response to environmental change. recent studies of penguin populations, the most commonly abundant antarctic seabirds in the west antarctic peninsula and western ross sea, have demonstrated that physical changes in antarctic marine ...201526488299
proliferation of east antarctic adélie penguins in response to historical deglaciation.major, long-term environmental changes are projected in the southern ocean and these are likely to have impacts for marine predators such as the adélie penguin (pygoscelis adeliae). decadal monitoring studies have provided insight into the short-term environmental sensitivities of adélie penguin populations, particularly to sea ice changes. however, given the long-term nature of projected climate change, it is also prudent to consider the responses of populations to environmental change over lon ...201526577544
ancient population genomics and the study of evolution.recently, the study of ancient dna (adna) has been greatly enhanced by the development of second-generation dna sequencing technologies and targeted enrichment strategies. these developments have allowed the recovery of several complete ancient genomes, a result that would have been considered virtually impossible only a decade ago. prior to these developments, adna research was largely focused on the recovery of short dna sequences and their use in the study of phylogenetic relationships, molec ...201525487332
re-constructing historical adélie penguin abundance estimates by retrospectively accounting for detection bias.seabirds and other land-breeding marine predators are considered to be useful and practical indicators of the state of marine ecosystems because of their dependence on marine prey and the accessibility of their populations at breeding colonies. historical counts of breeding populations of these higher-order marine predators are one of few data sources available for inferring past change in marine ecosystems. however, historical abundance estimates derived from these population counts may be subj ...201525909636
habitat use and sex-specific foraging behaviour of adélie penguins throughout the breeding season in adélie land, east antarctica.marine predators are ecosystem sentinels because their foraging behaviour and reproductive success reflect the variability occurring in the lower trophic levels of the ecosystem. in an era of environmental change, monitoring top predators species can provide valuable insights into the zones of ecological importance that need to be protected. in this context, we monitored the adélie penguin (pygoscelis adeliae) as a bio-indicator near dumont d'urville, an area of the east antarctic sector current ...201526392864
from warm to cold: migration of adélie penguins within cape bird, ross island.due to their sensitivity to environmental change, penguins in antarctica are widely used as bio-indicators in paleoclimatic research. on the basis of bio-element assemblages identified in four ornithogenic sediment profiles, we reconstructed the historical penguin population change at cape bird, ross island, for the past 1600 years. clear succession of penguin population peaks were observed in different profiles at about 1400 ad, which suggested a high probability of migration within this region ...201526113152
paternity testing using microsatellite dna markers in captive adélie penguins (pygoscelis adeliae).we investigated the paternity of 39 adélie penguins (pygoscelis adeliae) hatched at the port of nagoya public aquarium between 1995 and 2005 breeding seasons using microsatellite dna markers. among the 13 microsatellite marker loci tested in this study, eight markers amplified and were found to be polymorphic in the colony's founders of the captive population (n = 26). multiple marker analysis confirmed that all the hatchlings shared alleles with their social fathers and that none of them were s ...201425157452
winter and spring controls on the summer food web of the coastal west antarctic peninsula.understanding the mechanisms by which climate variability affects multiple trophic levels in food webs is essential for determining ecosystem responses to climate change. here we use over two decades of data collected by the palmer long term ecological research program (pal-lter) to determine how large-scale climate and local physical forcing affect phytoplankton, zooplankton and an apex predator along the west antarctic peninsula (wap). we show that positive anomalies in chlorophyll-a (chl-a) a ...201425000452
antarctic climate change: extreme events disrupt plastic phenotypic response in adélie penguins.in the context of predicted alteration of sea ice cover and increased frequency of extreme events, it is especially timely to investigate plasticity within antarctic species responding to a key environmental aspect of their ecology: sea ice variability. using 13 years of longitudinal data, we investigated the effect of sea ice concentration (sic) on the foraging efficiency of adélie penguins (pygoscelis adeliae) breeding in the ross sea. a 'natural experiment' brought by the exceptional presence ...201424489657
testing optimal foraging theory in a penguin-krill system.food is heterogeneously distributed in nature, and understanding how animals search for and exploit food patches is a fundamental challenge in ecology. the classic marginal value theorem (mvt) formulates optimal patch residence time in response to patch quality. the mvt was generally proved in controlled animal experiments; however, owing to the technical difficulties in recording foraging behaviour in the wild, it has been inadequately examined in natural predator-prey systems, especially those ...201424478293
mapping the abundance and distribution of adélie penguins using landsat-7: first steps towards an integrated multi-sensor pipeline for tracking populations at the continental scale.the last several years have seen an increased interest in the use of remote sensing to identify the location of penguin colonies in antarctica, and the estimation of the abundance of breeding pairs contained therein. high-resolution (sub-meter) commercial satellite imagery (e.g., worldview-1, quickbird) is capable of colony detection and abundance estimation for both large and small colonies, and has already been used in a continental-scale survey of adélie penguins. medium-resolution landsat im ...201425412466
decreasing prolactin levels leads to a lower diving effort but does not affect breeding success in adélie penguins.current research on seabirds suggests a key role of hormones in the trade-off between self-maintenance and parental investment through their influence on foraging decisions during the breeding period. although prolactin is known to have major effects on parental care, its role in foraging behavior has rarely been investigated in seabirds to date. the aim of this study was to assess the influence of an experimental decrease in prolactin levels on foraging decisions and its consequences on breedin ...201424333412
second generation dna sequencing of the mitogenome of the chinstrap penguin and comparative genomics of antarctic penguins.the complete mitochondrial genome of the chinstrap penguin (pygoscelis antarcticus) was sequenced and compared with other penguin mitogenomes. the genome is 15,972 bp in length with the number and order of protein coding genes and rnas being very similar to that of other known penguin mitogenomes. comparative nucleotide analysis showed the chinstrap mitogenome shares 94% homology with the mitogenome of its sister species, pygoscelis adelie (adélie penguin). divergence at nonsynonymous nucleotide ...201423795836
detection of evolutionarily distinct avian influenza a viruses in antarctica.abstract distinct lineages of avian influenza viruses (aivs) are harbored by spatially segregated birds, yet significant surveillance gaps exist around the globe. virtually nothing is known from the antarctic. using virus culture, molecular analysis, full genome sequencing, and serology of samples from adélie penguins in antarctica, we confirmed infection by h11n2 subtype aivs. their genetic segments were distinct from all known contemporary influenza viruses, including south american aivs, sugg ...201424803521
comparative genomic data of the avian phylogenomics project.the evolutionary relationships of modern birds are among the most challenging to understand in systematic biology and have been debated for centuries. to address this challenge, we assembled or collected the genomes of 48 avian species spanning most orders of birds, including all neognathae and two of the five palaeognathae orders, and used the genomes to construct a genome-scale avian phylogenetic tree and perform comparative genomics analyses (jarvis et al. in press; zhang et al. in press). he ...201425671091
a novel papillomavirus in adélie penguin (pygoscelis adeliae) faeces sampled at the cape crozier colony, antarctica.papillomaviruses are epitheliotropic viruses that have circular dsdna genomes encapsidated in non-enveloped virions. they have been found to infect a variety of mammals, reptiles and birds, but so far they have not been found in amphibians. using a next-generation sequencing de novo assembly contig-informed recovery, we cloned and sanger sequenced the complete genome of a novel papillomavirus from the faecal matter of adélie penguins (pygoscelis adeliae) nesting on ross island, antarctica. the g ...201424686913
have historical climate changes affected gentoo penguin (pygoscelis papua) populations in antarctica?the west antarctic peninsula (wap) has been suffering an increase in its atmospheric temperature during the last 50 years, mainly associated with global warming. this increment of temperature trend associated with changes in sea-ice dynamics has an impact on organisms, affecting their phenology, physiology and distribution range. for instance, rapid demographic changes in pygoscelis penguins have been reported over the last 50 years in wap, resulting in population expansion of sub-antarctic gent ...201424759777
trends in the breeding population of adélie penguins in the ross sea, 1981-2012: a coincidence of climate and resource extraction effects.measurements of the size of adélie penguin (pygoscelis adeliae) colonies of the southern ross sea are among the longest biologic time series in the antarctic. we present an assessment of recent annual variation and trends in abundance and growth rates of these colonies, adding to the published record not updated for more than two decades. high angle oblique aerial photographic surveys of colonies were acquired and penguins counted for the breeding seasons 1981-2012. in the last four years the nu ...201424621601
two antarctic penguin genomes reveal insights into their evolutionary history and molecular changes related to the antarctic environment.penguins are flightless aquatic birds widely distributed in the southern hemisphere. the distinctive morphological and physiological features of penguins allow them to live an aquatic life, and some of them have successfully adapted to the hostile environments in antarctica. to study the phylogenetic and population history of penguins and the molecular basis of their adaptations to antarctica, we sequenced the genomes of the two antarctic dwelling penguin species, the adélie penguin [pygoscelis ...201425671092
draft genome sequence of enterococcus faecalis strain pf3, isolated from adelie penguin feces from antarctica.enterococcus faecalis is one of the leading causes of nosocomial infections and is a common commensal organism in humans and other animals. in this study, we report a draft genome sequence for the e. faecalis strain pf3, isolated from adélie penguin feces collected from warriner island, antarctica.201424459271
diatom-specific highly branched isoprenoids as biomarkers in antarctic consumers.the structure, functioning and dynamics of polar marine ecosystems are strongly influenced by the extent of sea ice. ice algae and pelagic phytoplankton represent the primary sources of nutrition for higher trophic-level organisms in seasonally ice-covered areas, but their relative contributions to polar marine consumers remain largely unexplored. here, we investigated the potential of diatom-specific lipid markers and highly branched isoprenoids (hbis) for estimating the importance of these two ...201323418580
decreased prolactin levels reduce parental commitment, egg temperatures, and breeding success of incubating male adélie penguins.hormones regulate many aspects of an individual's phenotype, including various physiological and behavioral traits. two hormones have been described as important players in the regulation of parental investment in birds: the glucocorticoid hormone corticosterone and prolactin, a pituitary hormone, widely involved in mediating parental behavior. in comparison with corticosterone, the role of prolactin on parental investment remains poorly documented, and most studies so far have been correlative. ...201323770271
adélie penguin foraging location predicted by tidal regime switching.penguin foraging and breeding success depend on broad-scale environmental and local-scale hydrographic features of their habitat. we investigated the effect of local tidal currents on a population of adélie penguins on humble is., antarctica. we used satellite-tagged penguins, an autonomous underwater vehicle, and historical tidal records to model of penguin foraging locations over ten seasons. the bearing of tidal currents did not oscillate daily, but rather between diurnal and semidiurnal tida ...201323383091
ontogeny of muscle bioenergetics in adelie penguin chicks (pygoscelis adeliae).the ontogeny of pectoralis muscle bioenergetics was studied in growing adélie penguin chicks during the first month after hatching and compared with adults using permeabilized fibers and isolated mitochondria. with pyruvate-malate-succinate or palmitoyl-carnitine as substrates, permeabilized fiber respiration markedly increased during chick growth (3-fold) and further rose in adults (1.4-fold). several markers of muscle fiber oxidative activity (cytochrome oxidase, citrate synthase, hydroxyl-acy ...201324005252
trophic calculations reveal the mechanism of population-level variation in mercury concentrations between marine ecosystems: case studies of two polar seabirds.the incorporation of quantitative trophic level analysis in ecotoxicological studies provides explanatory power to identify the factors, trophic or environmental, driving population-level variation in mercury exposure at large geographic scales. in the antarctic marine ecosystem, mercury concentrations and stable isotope values in adélie penguins (pygoscelis adeliae) were compared between the antarctic peninsula and the ross sea. correcting tissue δ(15)n values for baseline δ(15)n values reveale ...201323993395
increase in penguin populations during the little ice age in the ross sea, antarctica.penguins are an important seabird species in antarctica and are sensitive to climate and environmental changes. previous studies indicated that penguin populations increased when the climate became warmer and decreased when it became colder in the maritime antarctic. here we determined organic markers in a sediment profile collected at cape bird, ross island, high antarctic, and reconstructed the history of adélie penguin colonies at this location over the past 700 years. the region transformed ...201323969993
growth prior to thermogenesis for a quick fledging of adélie penguin chicks (pygoscelis adeliae).the evolutionary trade-off between tissue growth and mature function restricts the post natal development of polar birds. the present study uses an original integrative approach as it includes gene expression, plus biochemical and physiological analysis to investigate how adélie penguin chicks achieve a rapid growth despite the energetic constraints linked to the cold and the very short breeding season in antarctica. in pectoralis muscle, the main thermogenic tissue in birds, our data show that ...201324040194
climate change winners: receding ice fields facilitate colony expansion and altered dynamics in an adélie penguin metapopulation.there will be winners and losers as climate change alters the habitats of polar organisms. for an adélie penguin (pygoscelis adeliae) colony on beaufort island (beaufort), part of a cluster of colonies in the southern ross sea, we report a recent population increase in response to increased nesting habitat as glaciers have receded. emigration rates of birds banded as chicks on beaufort to colonies on nearby ross island decreased after 2005 as available habitat on beaufort increased, leading to a ...201323573267
linking animal-borne video to accelerometers reveals prey capture variability.understanding foraging is important in ecology, as it determines the energy gains and, ultimately, the fitness of animals. however, monitoring prey captures of individual animals is difficult. direct observations using animal-borne videos have short recording periods, and indirect signals (e.g., stomach temperature) are never validated in the field. we took an integrated approach to monitor prey captures by a predator by deploying a video camera (lasting for 85 min) and two accelerometers (on th ...201323341596
monitoring trace elements in antarctic penguin chicks from south shetland islands, antarctica.the concentration of human activities in the near-shore ecosystems from the northern antarctic peninsula area can cause an increasing bioavailability of pollutants for the vulnerable antarctic biota. penguin chicks can reflect this potential impact in the rookeries during the breeding season. they also can reflect biomagnification phenomena since they are on the top of the antarctic food chain. the concentrations of al, cr, mn, fe, ni, cu, zn, as, se, cd and pb were measured by icp-ms in samples ...201323465574
adélie penguin population diet monitoring by analysis of food dna in scats.the adélie penguin is the most important animal currently used for ecosystem monitoring in the southern ocean. the diet of this species is generally studied by visual analysis of stomach contents; or ratios of isotopes of carbon and nitrogen incorporated into the penguin from its food. there are significant limitations to the information that can be gained from these methods. we evaluated population diet assessment by analysis of food dna in scats as an alternative method for ecosystem monitorin ...201324358158
elevated corticosterone levels and severe weather conditions decrease parental investment of incubating adélie penguins.corticosterone, the main stress hormone in birds, mediates resource allocation, allowing animals to adjust their physiology and behaviour to changes in the environment. incubation is a time and energy-consuming phase of the avian reproductive cycle. it may be terminated prematurely, when the parents' energy stores are depleted or when environmental conditions are severe. in this study, the effects of experimentally elevated baseline corticosterone levels on the parental investment of incubating ...201323291423
Refresh
firstprev
123
nextlast
Displaying items 1 - 100 of 233