differential leucocyte cell counts from the pygoscelid penguins of antarctica.differential leucocyte counts were obtained for three cogeneric species of wild antarctic penguins, pygoscelis adelie (adelie), pygoscelis papua (gentoo), and pygoscelis antarctica (chinstrap). significant differences between the differential leucocyte counts of the three species were not observed.19873625920
mercury and major essential elements in seals, penguins, and other representative fauna of the antarctic.concentrations of total hg and major essential elements, ca, mg, na, and k, were measured in the muscle, liver, and kidney of three species of seals, crabeater seal (lobodon carcinophagus), leopard seal (hydrurga leptonyx), and weddell seal (leptonychotes weddelli) collected in the antarctic. the muscle and liver of three species of penguins, i.e., gentoo penguin (pygoscelis papua), adelie penguin (p. adeliae), chinstrap penguin (p. antarctica), and other representative fauna were also analyzed ...19938239712
relics: penguin population programs.what has been responsible for the increase in chinstrap penguin populations during the past 40 years in maritime antarctica? one view ascribes it to an increase in availability of their prey brought on by the decrease in baleen whale stocks. the contrary opinion, attributes it to environmental warming. this causes a gradual decrease in the frequency of cold years with extensive winter sea ice cover. a number of penguin monitoring programs are in progress and are expected to provide some answers ...200111382136
the penguin feathers as bioindicator of antarctica environmental state.concentrations of biogenic and toxic elements (na, k, mg, ca, p, s, fe, cu, zn, co, mn, se, ni, sr, al, cd, pb, as) were determined for the first time in feathers of gentoo penguin (pygoscelis papua) and chinstrap penguin (pygoscelis antarctica) from antarctica. a comparison of element levels was performed among these species in years 2002-2003. penguins molt annually and this fact allows defining precisely the concentrations of accumulated toxic elements and heavy metals in plumage every year. ...200615967486
genetic diversity in populations of gentoo penguins (pygoscelis papua).rapd analysis was used to examine the extent of genetic polymorphism in two populations of gentoo penguin (pygoscelis papua) from antarctic islands (petermann and livingston). the chosen two of three 10 mer oligonucleotide primers accordingly to preliminary results showed different levels of polymorphism in gentoo penguins at petermann island (from 23.53 to 42.86%) and livingston island (from 52.94 to 57.14%). nei's similarity coefficients were in range from 0.5606 (when gentoo genome profiles w ...200616865990
marine pelagic ecosystems: the west antarctic peninsula.the marine ecosystem of the west antarctic peninsula (wap) extends from the bellingshausen sea to the northern tip of the peninsula and from the mostly glaciated coast across the continental shelf to the shelf break in the west. the glacially sculpted coastline along the peninsula is highly convoluted and characterized by deep embayments that are often interconnected by channels that facilitate transport of heat and nutrients into the shelf domain. the ecosystem is divided into three subregions, ...200717405208
polybrominated diphenyl ethers, polychlorinated dibenzo-dioxins, -furans, and -biphenyls in three species of antarctic seabirds are recognized to be at risk of accumulating toxic contaminants due to their high position in the trophic web and to their low ability to metabolize xenobiotic compounds. penguins are widely distributed in antarctica and represent an important fraction of the antarctic biomass. they feed mainly on krill and, depending on krill availability, also on fish. it has been reported that predators may be a sink for volatile and toxic chemicals and this may pose a serious environment ...200717993226
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
a novel adenovirus in chinstrap penguins (pygoscelis antarctica) in antarctica.adenoviruses (family adenoviridae) infect various organ systems and cause diseases in a wide range of host species. in this study, we examined multiple tissues from chinstrap penguins (pygoscelis antarctica), collected in antarctica during 2009 and 2010, for the presence of novel adenoviruses by pcr. analysis of a 855-bp region of the hexon gene of a newly identified adenovirus, designated chinstrap penguin adenovirus 1 (cspadv-1), showed nucleotide (amino acid) sequence identity of 71.8% (65.5% ...201424811321
genetic and molecular epidemiological characterization of a novel adenovirus in antarctic penguins collected between 2008 and 2013.antarctica is considered a relatively uncontaminated region with regard to the infectious diseases because of its extreme environment, and isolated geography. for the genetic characterization and molecular epidemiology of the newly found penguin adenovirus in antarctica, entire genome sequencing and annual survey of penguin adenovirus were conducted. the entire genome sequences of penguin adenoviruses were completed for two chinstrap penguins (pygoscelis antarctica) and two gentoo penguins (pygo ...201627309961
feather mercury concentrations in southern ocean seabirds: variation by species, site and time.we studied mercury contamination in 25 seabird species breeding along a latitudinal gradient across the southern ocean, from gough island (40°s) through marion island (47°s) to byers peninsula (63°s). total mercury concentrations in body feather samples of adults caught at breeding colonies from 2008 to 2011 were determined. krill (euphausia spp.) and other zooplankton consumers had low mercury concentrations (gentoo penguin pygoscelis papua, chinstrap penguin pseudomonas antarctica, common divi ...201627267741
isolation and characterization of macaroni penguin (eudyptes chrysolophus) microsatellite loci and their utility in other penguin species (spheniscidae, aves).we report the characterization of 25 microsatellite loci isolated from the macaroni penguin (eudyptes chrysolophus). thirteen loci were arranged into four multiplex sets for future genetic studies of macaroni penguin populations. all 25 loci were tested separately in each of four other penguin species [adélie penguin (pygoscelis adeliae), chinstrap penguin (pygoscelis antarctica), gentoo penguin (pygoscelis papua) and king penguin (aptenodytes patagonicus)]. between eight and 12 loci were polymo ...200921564950
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
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
gastrointestinal parasites in chinstrap penguins from deception island, south shetlands, antarctica.knowledge about parasites of antarctic birds is fragmented and scarce. the aim of this work is to contribute to the knowledge of gastrointestinal parasites of the chinstrap penguin (pygoscelis antarctica) from deception island (south shetlands, antarctica). gastrointestinal tracts of 64 fresh dead individuals (61 chicks and three adults) were collected from december 2006 to february 2009 and examined for macroparasites. three adult parasite species were found: two cestoda species (parorchites ze ...201222453499
identification of actinomycete communities in antarctic soil from barrientos island using pcr-denaturing gradient gel electrophoresis.the diversity of specific bacteria taxa, such as the actinomycetes, has not been reported from the antarctic island of barrientos. the diversity of actinomycetes was estimated with two different strategies that use pcr-denaturing gradient gel electrophoresis. first, a pcr was applied, using a group-specific primer that allows selective amplification of actinomycete sequences. second, a nested-pcr approach was used that allows the estimation of the relative abundance of actinomycetes within the b ...201222370930
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
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
morphological, molecular and phylogenetic analyses of the spirurid nematode stegophorus macronectes (johnston & mawson, 1942).stegophorus macronectes (johnston & mawson, 1942) is a gastrointestinal parasite found in antarctic seabirds. the original description of the species, which was based only on females, is poor and fragmented with some unclear diagnostic characters. this study provides new morphometric and molecular data on this previously poorly described parasite. nuclear rdna sequences (18s, 5.8s, 28s and internal transcribed spacer (its) regions) were isolated from s. macronectes specimens collected from the c ...201625871788
uropygial gland squamous cell carcinoma in chinstrap (pygoscelis antarcticus) and gentoo (pygoscelis papua) penguins at the wildlife conservation society's central park zoo.uropygial, or preen, glands are found in a variety of avian species including penguins. these glands have a multitude of functions and can develop a variety of conditions including impaction, rupture, adenitis, squamous metaplasia, and neoplasia of various types, with squamous cell carcinoma the most commonly reported. a case series of uropygial gland squamous cell carcinoma in five penguins at the wildlife conservation society's central park zoo is described. most birds were aged (>10 yr) with ...201525831583
mercury accumulation in sediments and seabird feathers from the antarctic an effort to assess the impact of mercury in the antarctic peninsula, we conducted ecotoxicological research in this region during the summer of 2012 and 2013. the objectives were to assess: (a) mercury levels in sediment samples; (b) mercury accumulation in antarctic seabird feathers: catharacta lonnbergi (brown skua), pygoscelis papua (gentoo penguin) and pygoscelis antarctica (chinstrap penguin); and (c) biomagnification (bmf predator/prey) and biota sediment accumulation (bsaf skuas/sedim ...201525455813
ontogeny of thermoregulation and energy metabolism in pygoscelid penguin chicks.the ontogeny of thermoregulation and energy metabolism of chinstrap (pygoscelis antarctica) and gentoo (p. papua) penguins was studied on king george island, south shetland island, antarctica. the major findings of this study are: chinstrap and gentoo penguin chicks hatched completely poikilothermic, due to their poor heat-production ability at low ambient temperatures. they were able to maintain high body temperatures and metabolic rates only by being brooded by adults. newly hatched chinstrap ...19853837032
pathogenic potential of environmental resident fungi from ornithogenic soils of antarctica.we assessed the diversity of cultivable fungi in the ornithogenic soil nests of bird species like phalacrocorax atriceps, macronectes giganteus, pygoscelis antarcticus, and pygoscelis papua in the antarctic islands. from 481 fungi isolated at 15 °c, only 50 displayed growth at 37 °c, and were identified as 14 species of 15 genera. aspergillus fumigatus, penicillium chrysogenum, and rhodotorula mucilaginosa were the most abundant species obtained. fifty taxa grew at 40 °c; displayed haemolytic an ...201729122179
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
blood transcriptome resources of chinstrap (pygoscelis antarcticus) and gentoo (pygoscelis papua) penguins from the south shetland islands, antarctica.the chinstrap (pygoscelis antarcticus) and gentoo (p. papua) penguins are distributed throughout antarctica and the sub-antarctic islands. in this study, high-quality de novo assemblies of blood transcriptomes from these penguins were generated using the illumina miseq platform. a total of 22.2 and 21.8 raw reads were obtained from chinstrap and gentoo penguins, respectively. these reads were assembled using the oases assembly platform and resulted in 26,036 and 21,854 contigs with n50 values of ...201930929406
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
divergent trophic responses of sympatric penguin species to historic anthropogenic exploitation and recent climate change.the southern ocean is in an era of significant change. historic overharvesting of marine mammals and recent climatic warming have cascading impacts on resource availability and, in turn, ecosystem structure and function. we examined trophic responses of sympatric chinstrap (pygoscelis antarctica) and gentoo (pygoscelis papua) penguins to nearly 100 y of shared environmental change in the antarctic peninsula region using compound-specific stable isotope analyses of museum specimens. a century ago ...201931792174
faecal microbiota changes associated with the moult fast in chinstrap and gentoo many seabirds, individuals abstain from eating during the moult period. penguins have an intense moult that lasts for weeks, during which they are confined to land. despite the importance for survival, it is still unclear how the faecal microbiota of antarctic penguins changes in response to the moult fast. here, we investigated the faecal microbiota of chinstrap (pygoscelis antarcticus) and gentoo penguins (pygoscelis papua) on king george island, antarctica. the bacterial community composit ...201931067284
time-lapse cameras reveal latitude and season influence breeding phenology durations in penguins.variation in the phenology of avian taxa has long been studied to understand how a species reacts to environmental changes over both space and time. penguins (sphenicidae) serve as an important example of how biotic and abiotic factors influence certain stages of seabird phenology because of their large ranges and the extreme, dynamic conditions present in their southern ocean habitats. here, we examined the phenology of gentoo (pygoscelis papua) and chinstrap penguins (pygoscelis antarctica) at ...201830250703
sponges as natural environmental dna a time of unprecedented impacts on marine biodiversity, scientists are rapidly becoming persuaded by the potential of screening large swathes of the oceans through the retrieval, amplification and sequencing of trace dna fragments left behind by marine organisms; an approach known as 'environmental dna' (edna) [1]. in trying to circumvent the many challenges associated with water filtration and dna isolation from environmental samples, significant investment is being made in high-tech solutio ...201931163139
blood glucose partition and levels of glycolytic enzymes in erythrocytes and somatic tissues of penguins.1. a comparative study was carried out on blood glucose partition and glucose metabolism of penguin erythrocytes and somatic tissues. pygoscelidae penguins (pygoscelis antarctica and p. papua) were used in these experiments. 2. blood glucose partition was established by assaying whole blood and plasma glucose in several individuals of the gentoo and chinstrap penguins. 3. it was found that almost all the whole blood sugar is compartmentalized at the plasma site, the red blood cells being ineffec ...19892924538
breeding time, health and immune response in the chinstrap penguin pygoscelis status and immunocompetence have been proposed as important factors affecting individual variation in the attainment of breeding condition in birds. we studied individual variation in serological variables indicating health status (blood sedimentation rate, haematocrit, `buffy coat' layer, proportions of different types of leucocytes) in two groups of breeding chinstrap penguins pygoscelis antarctica with breeding dates 9 days apart. we sampled these individuals shortly after hatching of ...199828308421
the use of medroxyprogesterone acetate to induce molting in chinstrap penguins (pygoscelis antarctica).molt was successfully induced with a progestational compound, medroxyprogesterone acetate (depo-provera), in six of six previously nonmolting chinstrap penguins (pygoscelis antarctica). the initial treatment consisted of five sequential weekly injections of 30 mg/kg depo-provera beginning in early september. four weeks after completing the injections, the penguins had gained an average of 23% body weight, but none had molted. beginning early november, five weekly injections were resumed, which i ...199910484146
seasonal shifts in the provisioning behavior of chinstrap penguins, pygoscelis antarctica.whether parents are able to adapt food gathering to rising offspring demands, or if they are controlled largely by extrinsic factors, is important for understanding key limits on fitness. over seven breeding seasons, we studied the provisioning behavior of chinstrap penguins, pygoscelis antarctica, at seal island, antarctica, during parents' transition to leave broods of one or two chicks unguarded. by measuring the frequency, duration, and diel timing of foraging trips and the quantity of prey ...200228547699
integrating stomach content and stable isotope analyses to quantify the diets of pygoscelid penguins.stomach content analysis (sca) and more recently stable isotope analysis (sia) integrated with isotopic mixing models have become common methods for dietary studies and provide insight into the foraging ecology of seabirds. however, both methods have drawbacks and biases that may result in difficulties in quantifying inter-annual and species-specific differences in diets. we used these two methods to simultaneously quantify the chick-rearing diet of chinstrap (pygoscelis antarctica) and gentoo ( ...201122053199
experimental assessment of the effects of gastrointestinal parasites on offspring quality in chinstrap penguins (pygoscelis antarctica).parasites reduce host fitness and consequently impose strong selection pressures on their hosts. it has been hypothesized that parasites are scarcer and their overall effect on hosts is weaker at higher latitudes. although antarctic birds have relatively low numbers of parasites, their effect on host fitness has rarely been investigated. the effect of helminth parasitism on growth rate was experimentally studied in chinstrap penguin (pygoscelis antarctica) nestlings. in a total of 22 two-nestlin ...201222310304
ecological sexual dimorphism and environmental variability within a community of antarctic penguins (genus pygoscelis).sexual segregation in vertebrate foraging niche is often associated with sexual size dimorphism (ssd), i.e., ecological sexual dimorphism. although foraging behavior of male and female seabirds can vary markedly, differences in isotopic (carbon, δ13c and nitrogen, δ15n) foraging niche are generally more pronounced within sexually dimorphic species and during phases when competition for food is greater. we examined ecological sexual dimorphism among sympatric nesting pygoscelis penguins asking wh ...201424599330
a reversal of fortunes: climate change 'winners' and 'losers' in antarctic peninsula penguins.climate change is a major threat to global biodiversity. antarctic ecosystems are no exception. investigating past species responses to climatic events can distinguish natural from anthropogenic impacts. climate change produces 'winners', species that benefit from these events and 'losers', species that decline or become extinct. using molecular techniques, we assess the demographic history and population structure of pygoscelis penguins in the scotia arc related to climate warming after the las ...201424865774
comparative osteohistology of hesperornis with reference to pygoscelid penguins: the effects of climate and behaviour on avian bone microstructure.the broad biogeographic distribution of hesperornis fossils in late cretaceous western interior seaway deposits has prompted questions about whether they endured polar winters or migrated between mid- and high latitudes. here, we compare microstructures of hesperornithiform long bones from kansas and the arctic to investigate whether migration or late cretaceous polar climate affected bone growth. we also examine modern penguin bones to determine how migration and climate may influence bone grow ...201426064560
age-related differences in the gastrointestinal microbiota of chinstrap penguins (pygoscelis antarctica).the gastrointestinal tract microbiota is known to play very important roles in the well being of animals. it is a complex community composed by hundreds of microbial species interacting closely among them and with their host, that is, a microbial ecosystem. the development of high throughput sequencing techniques allows studying the diversity of such communities in a realistic way and considerable work has been carried out in mammals and some birds such as chickens. wild birds have received less ...201627055030
relationship between legacy and emerging organic pollutants in antarctic seabirds and their foraging ecology as shown by δ(13)c and δ(15)n.foraging ecology and the marine regions exploited by antarctic seabirds outside of breeding strongly influence their exposure to persistent organic pollutants (pops). however, relationships between them are largely unknown, an important knowledge gap given that many species are capital breeders and pops may be deleterious to seabirds. this study investigates the relationship between antarctic seabird foraging ecology (measured by δ(13)c and δ(15)n) and pops accumulated in their eggs prior to bre ...201627453143
divergent responses of pygoscelis penguins reveal a common environmental driver.the responses of predators to environmental variability in the antarctic peninsula region have exhibited divergent patterns owing to variation in the geographic settings of colonies and predator life-history strategies. five breeding colonies of pygoscelis penguins from king george island and livingston island, south shetland islands, antarctica, were examined to (1) compare the responses of sympatric congeners to recent changes in their antarctic ecosystem and (2) assess underlying causes for s ...200717566778
wanted: dead or alive? isotopic analysis (δ13c and δ15n) of pygoscelis penguin chick tissues supports opportunistic sampling.physiological stress and starvation have been shown to affect δ(13)c and δ(15)n isotope values and, given that animals often die from starvation, the cause of death may be an important factor to consider in stable isotope analyses of opportunistically collected samples.201222302487
spatially integrated assessment reveals widespread changes in penguin populations on the antarctic important marine mesopredators and sensitive indicators of antarctic ecosystem change, penguins have been a major focus of long-term biological research in the antarctic. however, the vast majority of such studies have been constrained by logistics and relate mostly to the temporal dynamics of individual breeding populations from which regional trends have been inferred, often without regard for the complex spatial heterogeneity of population processes and the underlying environmental conditi ...201222834377
penguin eggshell membranes reflect homogeneity of mercury in the marine food web surrounding the antarctic peninsula.remote regions such as the antarctic have become increasingly important for investigations into far-reaching anthropogenic impacts on the environment, most recently in regard to the global mercury cycle. spatial patterns of mercury availability in four regions of the antarctic peninsula were investigated using three species of sympatrically breeding pygoscelis penguins as biomonitors. eggshells with intact membranes from adélie, gentoo, and chinstrap penguins were collected at 24 breeding coloni ...201223069932
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
from the cover: variability in krill biomass links harvesting and climate warming to penguin population changes in antarctica.the west antarctic peninsula (wap) and adjacent scotia sea support abundant wildlife populations, many of which were nearly extirpated by humans. this region is also among the fastest-warming areas on the planet, with 5-6 °c increases in mean winter air temperatures and associated decreases in winter sea-ice cover. these biological and physical perturbations have affected the ecosystem profoundly. one hypothesis guiding ecological interpretations of changes in top predator populations in this re ...201121482793
a global population assessment of the chinstrap penguin (pygoscelis antarctica).using satellite imagery, drone imagery, and ground counts, we have assembled the first comprehensive global population assessment of chinstrap penguins (pygoscelis antarctica) at 3.42 (95th-percentile ci: [2.98, 4.00]) million breeding pairs across 375 extant colonies. twenty-three previously known chinstrap penguin colonies are found to be absent or extirpated. we identify five new colonies, and 21 additional colonies previously unreported and likely missed by previous surveys. limited or impre ...202033173126
occurrence, distribution, and bioaccumulation of new and legacy persistent organic pollutants in an ecosystem on king george island, maritime antarctica.the occurrence and bioaccumulation of new and legacy persistent organic pollutants (pops), organochlorine pesticides (ocps), polychlorinated biphenyls (pcbs), polychlorinated naphthalenes (pcns), hexabromocyclododecanes (hbcds), and dechlorane plus (dps) and their related compounds (dechloranes) in an ecosystem on king george island, antarctica are investigated. the new and legacy pops were widely detected in the animal samples collected from antarctica, which included limpet, antarctic cod, amp ...202033087285
mercury exposure in humboldt (spheniscus humboldti) and chinstrap (pygoscelis antarcticus) penguins throughout the chilean coast and antarctica.penguins are reliable sentinels for environmental assessments of mercury (hg) due to their longevity, abundance, high trophic level, and relatively small foraging areas. we analyzed hg concentrations from blood and feathers of adult humboldt penguins (spheniscus humboldti) and feathers of chinstrap penguins (pygoscelis antarcticus) from different reproductive colonies with variable degrees of urbanization and industrialization along the chilean and antarctic coasts. we evaluated hg concentration ...201829725722
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
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
antarctic krill fishery effects over penguin populations under adverse climate conditions: implications for the management of fishing climate changes in the western antarctic peninsula are reducing krill density, which along with increased fishing activities in recent decades, may have had synergistic effects on penguin populations. we tested that assumption by crossing data on fishing activities and southern annular mode (an indicator of climate change in antarctica) with penguin population data. increases in fishing catch during the non-breeding period were likely to result in impacts on both chinstrap (pygoscelis antar ...202032979187
individual variation in migratory movements of chinstrap penguins leads to widespread occupancy of ice-free winter habitats over the continental shelf and deep ocean basins of the southern ocean.a goal of tracking migratory animals is to characterize the habitats they use and to interpret population processes with respect to conditions experienced en route to, and within, overwintering areas. for migratory seabirds with broad breeding ranges, inferring population-level effects of environmental conditions that are experienced during migratory periods would benefit by directly comparing how birds from different breeding aggregations disperse, characterizing the physical conditions of area ...201931821380
niche partitioning of sympatric penguins by leapfrog foraging appears to be resilient to climate change.interspecific competition can drive niche partitioning along multidimensional axes, including allochrony. competitor matching will arise where the phenology of sympatric species with similar ecological requirements responds to climate change at different rates such that allochrony is reduced. our study quantifies the degree of niche segregation in foraging areas and depths that arises from allochrony in sympatric adélie and chinstrap penguins and explores its resilience to climate change. three- ...201930378103
correction to: chinstrap penguin population genetic structure: one or more populations along the southern ocean?correction to: bmc evolutionary biology (2018) 18:90 .201830045693
chinstrap penguin population genetic structure: one or more populations along the southern ocean?historical factors, demography, reproduction and dispersal are crucial in determining the genetic structure of seabirds. in the antarctic marine environment, penguins are a major component of the avian biomass, dominant predators and important bioindicators of ecological change. populations of chinstrap penguins have decreased in nearly all their breeding sites, and their range is expanding throughout the antarctic peninsula. population genetic structure of this species has been studied in some ...201829898661
technique, postoperative complications, and visual outcomes of phacoemulsification cataract surgery in 21 penguins (27 eyes): describe surgical technique, postoperative complications, and visual outcome in penguins after phacoemulsification lens extraction surgery.201829411487
multiple sex chromosome system in penguins (pygoscelis, spheniscidae).penguins are classified in the order sphenisciformes into a single family, spheniscidae. the genus pygoscelis wagler, 1832, is composed of three species, pygoscelis antarcticus forster, 1781, p. papua forster, 1781 and p. adeliae hombron & jacquinot, 1841. in this work, the objective was to describe and to compare the karyotypes of pygoscelis penguins contributing genetic information to sphenisciformes. the metaphases were obtained by lymphocyte culture, and the diploid number and the c-banding ...201729093802
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
pygoscelis antarcticus feathers as bioindicator of trace element risk in marine environments from barton peninsula, 25 de mayo (king george) island, antarctica.we report the contents of elements in feathers of chinstrap penguin (pygoscelis antarcticus), which had not been informed up to now, such as silver and bromine and others listed as hazardous by the united states environmental protection agency as arsenic, cobalt, chromium, and mercury. analyses of the element concentrations in feathers, adult and chicken, from barton peninsulas at 25 de mayo (king george) island, south shetlands, were made by instrumental neutron activation analysis. samarium, l ...201728286909
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