| plasma proteins and immunoglobulins in penguins (pygoscelis adeliae). | total and fractionated proteins were evaluated in the serum of normal penguins. four proteins with antibody activity, determined by passive haemagglutination, were isolated by sephadex g-200 filtration and deae-cellulose chromatography, from the serum of penguins (pygoscelis adeliae) inoculated with dinitrophenylated human gamma-globulin. immunoelectrophoresis and immunodiffusion showed that all these proteins exhibited both their own and shared antigenic determinants. on account of their electr ... | 1975 | 50086 |
| spontaneous and bile salt stimulated bile secretion in the adelie penguin (pygoscelis adeliae). | the flow rate and ionic composition of bile during spontaneous secretion were measured in anaesthetized penguins in which the enterohepatic circulation had been interrupted and with i.v. injection of saline to replace secretory loss. during the first two hours the rate of flow increased, and then remained relatively constant for a further two and a half hours. during this time the concentration of bile salt fell, but the concentrations of other ions showed small fluctuations only. sodium tauroch ... | 1978 | 244360 |
| the relation between structure and function of bile ducts in man, some laboratory animals and the adelie penguin. | the biliary trees of man, dog, cat, rabbit, rat, guinea pig and penguin were examined in histological sections and by latex casts. the trees of man, dog, and cat were similar with only minor differences. tubulo-alveolar glands were present in all three species around large intrahepatic ducts and in large portal tracts there were zones of ductules (areas with many small bile ducts), surrounded by small vessels with no apparent relation to hepatocytes. both these features were present in the guine ... | 1979 | 256628 |
| light microscopic study of granulocytes of pygoscelid penguins (pygoscelis adeliae) of antarctica. | morphologic features of heterophils, eosinophils, and basophils of wild adult pygoscelid penguins (pygoscelis adeliae; 1 male, 4 females) of antarctica were studied. granulocytes were described on the basis of analysis of stained blood films and of 0.5-micron sections of centrifuged resin-embedded blood. morphometric analysis of granulocytes included average cell diameter, cell shape, and nuclear configuration as well as the number, size, and shape of intracytoplasmic granules. large round heter ... | 1988 | 2460002 |
| 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. | 1987 | 3625920 |
| the endocrine control of reproduction and molt in male and female emperor (aptenodytes forsteri) and adelie (pygoscelis adeliae) penguins. ii. annual changes in plasma levels of thyroxine and triiodothyronine. | changes in plasma thyroxine (t4) and triiodothyronine (t3) levels were studied during a breeding season and in more detail during the postbreeding molt in male and female emperor (aptenodytes forsteri) and adelie (pygoscelis adeliae) penguins under natural conditions in the antarctic. during the 4-month natural fast that accompanies courtship and incubation in male emperors, plasma t4 and t3 levels were maintained around 11 and 0.6 ng/ml, respectively. in courting, fasting female emperors plasma ... | 1986 | 3781233 |
| salmonella in adélie penguins (pygoscelis adeliae) and south polar skuas (catharacta maccormicki) on ross island, antarctica. | | 1973 | 4583956 |
| virological studies of adelie penguins (pygoscelis adeliae) in antarctica. | serum antibodies to influenza virus hemagglutinin 7, newcastle disease virus (ndv), and avian paramyxoviruses were detected in adelie penguin colonies in antarctica. infection with ndv and avian influenza virus was confined to particular colonies, whereas antibodies to the paramyxoviruses were detected in all seven colonies samples. two avian paramyxoviruses were also isolated fromcloacal swabs. results of serological tests must be interpreted with caution, as little as known about the persisten ... | 1981 | 7039589 |
| 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 ... | 1993 | 8239712 |
| evidence of ortho- and paramyxoviruses in fauna from antarctica. | serum antibodies to influenza a viruses and paramyxoviruses were detected in adelie penguin (pysoscelis adeliae) and antarctic skua (stercorarius skua maccormicki) sera in the ross sea dependency. an avian paramyxovirus was isolated from a penguin cloacal swab. | 1993 | 8258855 |
| novel psychrobacter species from antarctic ornithogenic soils. | ornithogenic soil is derived from the deposition of the fecal matter of various species of birds and is a major source of nutrient input in the antarctic marine ecosystem. a significant proportion of microbiota of ornithogenic soil collected from an adélie penguin colony in eastern antarctica (vestfold hills ice-free zone) consisted of gram-negative, coccoid bacteria identified on the basis of their phospholipid ester-linked fatty acid and lipid class profiles as psychrobacter strains. phenotypi ... | 1996 | 8863407 |
| injuries to avian researchers at palmer station, antarctica from penguins, giant petrels, and skuas. | this paper describes 5 cases of injury to seabird researchers between 1996 and 1999 at palmer station, antarctica. the injuries were inflicted by 3 seabird species: the adelie penguin (pygoscelis adeliae); the southern giant petrel (macronectes giganteus); and the brown skua (catharacta lonnbergi). all injured parties were biologic researchers with previous field experience working under national science foundation research grants; all sought medical evaluation and treatment voluntarily. the nat ... | 2000 | 10921359 |
| cholangiocarcinoma with metastasis in a captive adelie penguin (pygoscelis adeliae). | a captive male adelie penguin (pygoscelis adeliae), wild caught in 1976, died unexpectedly. necropsy revealed cholangiocarcinoma with metastases to lung, pancreas, mesentery, and cloaca, the first known case of a penguin hepatic tumor. | 2001 | 12785690 |
| viability of coliform bacteria in antarctic soil. | boyd, william l. (ohio state university, columbus) and josephine w. boyd. viability of coliform bacteria in antarctic soil. j. bacteriol. 85:1121-1123. 1963.-the distribution of coliform bacteria in soils of ross island and the nearby mainland was studied. none was found in almost all of the samples collected, including some from the adelie penguin rookeries at cape royds and cape crozier and in soil at the mcmurdo base which had been recently contaminated by human sewage. samples of pony manure ... | 1963 | 14044003 |
| 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 ... | 2006 | 16865990 |
| 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, ... | 2007 | 17405208 |
| polybrominated diphenyl ethers, polychlorinated dibenzo-dioxins, -furans, and -biphenyls in three species of antarctic penguins. | fish-eating 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 ... | 2007 | 17993226 |
| competition among penguins and cetaceans reveals trophic cascades in the western ross sea, antarctica. | an apparent trophic cascade that appears during summer in the western ross sea, antarctica, explains why the antarctic silverfish (pleuragramma antarcticum) there becomes cannibalistic; its principal prey, crystal krill (euphausia crystallorophias) becomes scarce; and the diatom community is minimally grazed compared to adjacent areas. the krill is the major grazer of diatoms. on the basis of fieldwork at ross island, we suggest that the cascade results from foraging by unusually numerous adélie ... | 2006 | 16937647 |
| corticosterone in relation to body mass in adelie penguins (pygoscelis adeliae) affected by unusual sea ice conditions at ross island, antarctica. | penguins naturally fast each year during breeding and again whilst moulting, and may lose more than 40% of body mass during a fast. fasting in emperor (aptenodytes forsteri) and king (aptenodytes patagonicus) penguins has been divided into three phases, with phase iii characterised by an increased rate of body mass loss, increased plasma corticosterone concentrations, and a change in behaviour leading to abandonment of the breeding attempt and return to sea to feed. initial corticosterone concen ... | 2006 | 16876799 |
| arthrobacter psychrochitiniphilus sp. nov., a psychrotrophic bacterium isolated from antarctica. | a psychrotrophic arthrobacter strain, gp3(t), was isolated from adélie penguin guano from antarctica and characterized. the 16s rrna gene sequence of the novel strain showed the highest similarity (97.8 %) with that of arthrobacter psychrolactophilus b7(t). the novel strain showed a morphological change from rod to coccus. the growth temperature range of strain gp3(t) was 0-25 degrees c, with optimal growth at 20 degrees c. the strain grew over a salinity range of between 0 and 3 % (w/v) nacl an ... | 2009 | 19625417 |
| outbreaks of avian cholera in hope bay, antarctica. | during austral summers 1999-2000 and 2000-01, two outbreaks of avian cholera occurred in the hope bay area (63 degrees 24's, 56 degrees 59'w), located on the tip of the antarctic peninsula. eighty-six dead birds were found: five kelp gulls (larus dominicanus), 36 skuas (stercorarius sp.), and 45 adelie penguins (pygoscelis adeliae). the carcasses were studied using clinical, pathological, and microbiological criteria. water samples from ponds where birds were settled and samples from 90 healthy ... | 2006 | 16870848 |
| microevolution and mega-icebergs in the antarctic. | microevolution is regarded as changes in the frequencies of genes in populations over time. ancient dna technology now provides an opportunity to demonstrate evolution over a geological time frame and to possibly identify the causal factors in any such evolutionary event. using nine nuclear microsatellite dna loci, we genotyped an ancient population of adélie penguins (pygoscelis adeliae) aged approximately 6,000 years b.p. subfossil bones from this population were excavated by using an accurate ... | 2005 | 16275908 |
| ontogeny of hepatic microsomal 3-hydroxylation of quinine in adélie penguins. | ontogeny of hepatic cytochrome p450 (cyp) content and of quinine 3-hydroxylation, a biomarker of human cyp3a activity, was investigated in adélie penguins (pygoscelis adeliae) by comparing liver microsomes from chicks aged 13-28 days (n=10) with those from adults. the total cyp content in chick microsomes was significantly lower than in adults and correlated with the age of the chicks (r=0.894, p<0.001). kinetic parameters (mean+/-s.d.) for quinine 3-hydroxylation in chick microsomes were lower ... | 2004 | 15313446 |
| ancient dna enables timing of the pleistocene origin and holocene expansion of two adélie penguin lineages in antarctica. | the timing of divergent events in history is one of the central goals of contemporary evolutionary biology. such studies are however dependent on accurate evolutionary rates. recent developments in ancient dna analysis enable the estimation of more accurate evolutionary rates and therefore more accurate timing of divergence events. consequently, this leads to a better understanding of changes in populations through time. we use an evolutionary rate calculated from ancient dna of adélie penguins ... | 2004 | 14595092 |
| development of a highly sensitive screen for influenza a in guano and its application in the search for ancient rna preserved under antarctic adelie penguin colonies. | we have developed a reverse transcriptase polymerase chain reaction (rt-pcr)-based assay to detect influenza a in guano samples as part of our program to investigate ancient viral rna from under antarctic adelie penguin (pygoscelis adeliae) colonies. of five extraction protocols tested (rneasy, gtc trizol, gtc silica, rnaid, and agpc), agpc proved to be the most consistent and sensitive to low concentrations of influenza, but further purification with commercial viral nucleic acid spin filter sy ... | 2003 | 14575142 |
| assumption and elimination of trace elements in adélie penguins from antarctica: a preliminary study. | the concentration and distribution of some trace elements were determined in stomach contents, excreta and feathers of adélie penguins (pygoscelis adeliae) breeding at edmonson point (terra nova bay-antarctica). in these materials obtained by non-destructive methods, concentrations of mercury, cadmium and lead measured were used to establish natural levels of these metals in the penguins' diet. an intake-excretion hypothesis was formulated. | 2002 | 12408585 |
| rates of evolution in ancient dna from adélie penguins. | well-preserved subfossil bones of adélie penguins, pygoscelis adeliae, underlie existing and abandoned nesting colonies in antarctica. these bones, dating back to more than 7000 years before the present, harbor some of the best-preserved ancient dna yet discovered. from 96 radiocarbon-aged bones, we report large numbers of mitochondrial haplotypes, some of which appear to be extinct, given the 380 living birds sampled. we demonstrate dna sequence evolution through time and estimate the rate of e ... | 2002 | 11910113 |
| prolactin and parental behavior in adélie penguins: effects of absence from nest, incubation length, and nest failure. | adélie penguin (pygoscelis adeliae) males and females, nesting in antarctica, alternate attendance at the nest with absences of many days to forage at sea. we investigated the importance of tactile input from egg and chicks on prolactin levels by observing nest attendance patterns and obtaining blood samples (1) during the first nest exchange of the incubation stage, (2) from birds whose incubation period was artificially increased or decreased by about 10 days, and (3) from birds whose nests ha ... | 2000 | 11038289 |
| in vitro hepatic metabolism of a cyp3a-mediated drug, quinine, in adélie penguins. | very little is known about antarctic animals' ability to metabolise or detoxify xenobiotics. the activity of cytochromes p450 subfamily 3a (cyp3a) in adélie penguin liver was studied by incubating penguin liver microsomes with a human cyp3a substrate, quinine, and results were compared with those from human liver microsomes. the mean maximum rate of metabolism (vmax) for quinine in penguin livers was approximately five times less (160+/-72 versus 574+/-416 pmol/mg/min; p<0.01), and the mean km ( ... | 1999 | 10661723 |
| aspergillus spp. seropositivity in new zealand penguins. | one hundred-fifty yellow-eyed penguins (megadyptes antipodes) of 8 populations, 20 little blue penguins (eudyptula minor) of 2 populations, 9 rockhopper penguins (eudyptes chrysocome), and 5 adelie penguins (pygoscelis adeliae) from new zealand (nz) and antarctica (latitude range; 39 degrees 30' s - 77 degrees 13' s) were tested by indirect enzyme-linked immunosorbent assays (elisa) for fungal aspergillus spp. igg. one hundred-ten of 184 (60%) penguins were seropositive, and seroprevalence was r ... | 1995 | 8587585 |
| [paracoccidioides brasiliensis, a new sample isolated from feces of a penguin (pygoscelis adeliae)]. | the authors show the results obtained through the study of a paracoccidioides strain isolated from a penguin in the uruguaian antartide by gezuele et al. (1989). from the fecal mater it was isolated a fungus which was recently considered as a new species of the genus paracoccidioides--p. antarcticus. however, the mycological and immunochemical studies including the demonstration of the 43 kda glycoprotein by immunodiffusion test, sds-page and immunoelectrophoresis disclosed that such strain is s ... | 1993 | 8278752 |
| penguin egg-white and polar fish blood-serum proteins. | the development of, and findings in, a long-term research program on penguin proteins and polar fish blood proteins are described. two of the egg-white proteins from the adelie penguin (pygoscelis adeliae) have unique properties: a glycoprotein named penalbumin that is a major constituent with some characteristics similar to ovalbumin, and an ovomucoid with strong inhibitory capacity for subtilisin as well as for bovine trypsin and alpha-chymotrypsin. the antifreeze glycoproteins from antarctic ... | 1982 | 6749729 |
| the endocrine control of reproduction and molt in male and female emperor (aptenodytes forsteri) and adelie (pygoscelis adeliae) penguins. i. annual changes in plasma levels of gonadal steroids and lh. | changes in plasma lh, testosterone, and estrogens were investigated throughout reproduction and molt in free-living male and female emperor (aptenodytes forsteri) and adelie (pygoscelis adeliae) penguins. in both sexes and species, plasma lh and gonadal steroids were severalfold above basal level at the time of arrival on the breeding grounds, suggesting that environmental cues (especially decreasing daylength in emperors) rather than mating and courting primarily stimulate gonadal development a ... | 1986 | 3781216 |
| plasma melatonin in the adelie penguin (pygoscelis adeliae) under conditions daylight in antarctica. | circadian rhythms of melatonin secretion in birds are influenced by daylength and light intensity. daily patterns of melatonin secretion were examined in adelie penguins (pygoscelis adeliae) under natural continuous daylight at cape bird, antarctica (77 degrees s). although daylight is continuous during the antarctic summer there was a marked daily cycle of light intensity. however, there was no relationship between mean plasma melatonin levels and time of day in groups of 2-10 penguins sampled ... | 1991 | 2056428 |
| nonlinear effects of winter sea ice on the survival probabilities of adélie penguins. | the population dynamics of antarctic seabirds are influenced by variations in winter sea ice extent and persistence; however, the type of relationship differs according to the region and the demographic parameter considered. we used annual presence/absence data obtained from 1,138 individually marked birds to study the influence of environmental and individual characteristics on the survival of adélie penguins pygoscelis adeliae at edmonson point (ross sea, antarctica) between 1994 and 2005. abo ... | 2009 | 19543920 |
| 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 ... | 2009 | 21564950 |
| corticosterone responses in birds: individual variation and repeatability in adelie penguins (pygoscelisadeliae) and other species, and the use of power analysis to determine sample sizes. | plasma corticosterone concentrations increase when birds experience a stressor, and in this study we quantified variation in corticosterone responses for the first time in a species of free-living bird. adelie penguins (pygoscelisadeliae) nesting at cape bird on ross island in antarctica were sampled on three occasions. penguins with relatively low or high corticosterone responses on the first occasion had consistently low or high responses, as previously found for great tits and chickens. a mod ... | 2009 | 19351536 |
| 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 ... | 2016 | 26874670 |
| bacterial diversity associated with ornithogenic soil of the ross sea region, antarctica. | in the ross sea region of antarctica, ornithogenic soils form on land under adélie penguin rookeries. compared with mineral soils of the ross sea region, ornithogenic soils are generally high in microbial biomass, organic carbon, and total nitrogen and phosphorus, with high electrical conductivity and large variations in ph. the objective of this study was to assess the bacterial composition of ornithogenic soils from cape hallett and cape bird in the ross sea region using culture-independent me ... | 2009 | 19190698 |
| mutation and evolutionary rates in adélie penguins from the antarctic. | precise estimations of molecular rates are fundamental to our understanding of the processes of evolution. in principle, mutation and evolutionary rates for neutral regions of the same species are expected to be equal. however, a number of recent studies have shown that mutation rates estimated from pedigree material are much faster than evolutionary rates measured over longer time periods. to resolve this apparent contradiction, we have examined the hypervariable region (hvr i) of the mitochond ... | 2008 | 18833304 |
| 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 ... | 2016 | 26952994 |
| growing in antarctica, a challenge for white adipose tissue development in adelie penguin chicks (pygoscelis adeliae). | rapid growth is of crucial importance for adélie penguin chicks reared during the short antarctic summer. it partly depends on the rapid ontogenesis of fat stores that are virtually null at hatching but then develop considerably (x40) within a month to constitute both an isolative layer against cold and an energy store to fuel thermogenic and growth processes. the present study was aimed at identifying by rt-pcr the major transcriptional events that chronologically underlie the morphological tra ... | 2008 | 18799630 |
| salmonella infections in antarctic fauna and island populations of wildlife exposed to human activities in coastal areas of australia. | salmonella infections in antarctic wildlife were first reported in 1970 and in a search for evidence linking isolations with exposure to human activities, a comparison was made of serovars reported from marine fauna in the antarctic region from 1982-2004 with those from marine mammals in the northern hemisphere. this revealed that 10 (83%) salmonella enterica serovars isolated from antarctic penguins and seals were classifiable in high-frequency (hf) quotients for serovars prevalent in humans an ... | 2009 | 18789175 |
| liver and heart mitochondria obtained from adelie penguin (pygoscelis adeliae) offers high resistance to lipid peroxidation. | lipid peroxidation is generally thought to be a major mechanism of cell injury in aerobic organisms subjected to oxidative stress. all cellular membranes are especially vulnerable to oxidation due to their high concentration of polyunsaturated fatty acids. however, birds have special adaptations for preventing membrane damage caused by reactive oxygen species. this study examines fatty acid profiles and susceptibility to lipid peroxidation in liver and heart mitochondria obtained from adelie pen ... | 2008 | 18637558 |
| corticosterone responses to capture and restraint in emperor and adelie penguins in antarctica. | birds respond to capture, handling and restraint with increased secretion of corticosterone, a glucocorticoid hormone that helps birds adjust to stressful situations. hoods are reported to calm birds, but possible effects of hoods on corticosterone responses have not been reported for any bird. corticosterone responses to restraint in adelie penguins held by their legs with their head covered by a hood were markedly lower than responses of penguins restrained in a mesh bag inside a cardboard box ... | 2008 | 18393566 |
| abrupt recent shift in delta 13c and delta 15n values in adélie penguin eggshell in antarctica. | stable isotope values of carbon (delta13c) and nitrogen (delta15n) in blood, feathers, eggshell, and bone have been used in seabird studies since the 1980s, providing a valuable source of information on diet, foraging patterns, and migratory behavior in these birds. these techniques can also be applied to fossil material when preservation of bone and other tissues is sufficient. excavations of abandoned adélie penguin (pygoscelis adeliae) colonies in antarctica often provide well preserved remai ... | 2007 | 17620620 |
| comparing plasma and faecal measures of steroid hormones in adelie penguins pygoscelis adeliae. | physiological measurements of both stress and sex hormones are often used to estimate the consequences of natural or human-induced change in ecological studies of various animals. different methods of hormone measurement exist, potentially explaining variation in results across studies; methods should be cross-validated to ensure that they correlate. we directly compared faecal and plasma hormone measurements for the first time in a wild free-living species, the adelie penguin (pygoscelis adelia ... | 2010 | 19609534 |
| bacterial diversity in adélie penguin, pygoscelis adeliae, guano: molecular and morpho-physiological approaches. | the total number of bacteria and culturable bacteria in adélie penguin (pygoscelis adeliae) guano was determined during 42 days of decomposition in a location adjacent to the rookery in admiralty bay, king george island, antarctica. of the culturable bacteria, 72 randomly selected colonies were described using 49 morpho-physiological tests, 27 of which were subsequently considered significant in characterizing and differentiating the isolates. on the basis of the nucleotide sequence of a fragmen ... | 2004 | 19712357 |
| 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% ... | 2017 | 28124141 |
| 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.]. | 2016 | 27792768 |
| 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 ... | 2016 | 27783668 |
| 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 ... | 2016 | 27450255 |
| 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 ... | 2016 | 27400905 |
| 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 ... | 2016 | 27352849 |
| 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 ... | 2016 | 27195682 |
| an antarctic hot spot for fungi at shackleton's historic hut on cape royds. | the historic expedition huts located in the ross sea region of the antarctic and the thousands of artifacts left behind by the early explorers represent important cultural heritage from the "heroic era" of polar exploration. the hut at cape royds built by ernest shackleton and members of the 1907-1908 british antarctic expedition has survived the extreme antarctic environment for over 100 years, but recent studies have shown many forms of deterioration are causing serious problems, and microbial ... | 2010 | 20386896 |
| survival differences and the effect of environmental instability on breeding dispersal in an adelie penguin meta-population. | high survival and breeding philopatry was previously confirmed for the adélie penguin (pygoscelis adeliae) during a period of stable environmental conditions. however, movements of breeding adults as a result of an unplanned natural experiment within a four-colony meta-population provided interesting insights into this species' population dynamics. we used multistate mark-recapture models to investigate apparent survival and dispersal of breeding birds in the southwestern ross sea during 12 bree ... | 2010 | 20566874 |
| lack of leptin activity in blood samples of adélie penguin and bar-tailed godwit. | unsuccessful attempts to identify the leptin gene in birds are well documented, despite the characterization of its receptor (lepr). since leptin and lepr have poor sequence conservation among vertebrates, we speculated that a functional assay should represent the best way to detect leptin in birds. using a leptin bioassay that is based on activation of the chicken lepr in cultured cells, blood samples from wild birds with extreme seasonal variation in voluntary food intake and fat deposition (a ... | 2010 | 20675300 |
| responding to climate change: adélie penguins confront astronomical and ocean boundaries. | long-distance migration enables many organisms to take advantage of lucrative breeding and feeding opportunities during summer at high latitudes and then to move to lower, more temperate latitudes for the remainder of the year. the latitudinal range of the adélie penguin (pygoscelis adeliae) spans approximately 22 degrees. penguins from northern colonies may not migrate, but due to the high latitude of ross island colonies, these penguins almost certainly undertake the longest migrations for the ... | 2010 | 20715628 |
| concentration of trace elements in feathers of three antarctic penguins: geographical and interspecific differences. | antarctica is often considered as one of the last pristine regions, but it could be affected by pollution at global and local scale. concentrations of al, cr, mn, fe, ni, cu, zn, as, se, cd and pb were determinated by icp-ms in feathers (n = 207 individuals) of gentoo, chinstrap and adélie penguin collected in 8 locations throughout the antarctic peninsula (2006-2007). the highest levels of several elements were found in samples from king george island (8.08, 20.29 and 1.76 µg g(-1) dw for cr, c ... | 2011 | 21764193 |
| 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 ... | 2015 | 26488299 |
| chlorinated biphenyls and pesticides in migrating and resident seabirds from east and west antarctica. | the unhatched eggs of the following seabirds were analyzed to quantify pcbs, hexachlorobenzene (hcb), +¦-, +¦-, +¦-, +¦-hexachlorocyclohexanes (hchs), o,p' and p,p' isomers of ddt, ddd and dde: resident ad+¿lie (pygoscelis ad+¿liae, adpe) and emperor (aptenodytes forsteri, empe) penguins, migrating snow petrel (pagodroma nivea, snpt) and south polar skua (catharacta maccormicki, spsk) from the ross sea (east antarctica); and migrating brown skua (catharacta antartica, brsk) and resident adpe fro ... | 2011 | 21704375 |
| 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 ... | 2017 | 28091764 |
| 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 ... | 2015 | 25909636 |
| 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. | 2014 | 24459271 |
| 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 ... | 2016 | 27535050 |
| 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 ... | 2015 | 25537375 |
| 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 ... | 2014 | 24803521 |
| 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 ... | 2013 | 23418580 |
| 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 ... | 2014 | 24621601 |
| penguin tissue as a proxy for relative krill abundance in east antarctica during the holocene. | antarctic krill (euphausia superba) is a key component of the southern ocean food web. it supports a large number of upper trophic-level predators, and is also a major fishery resource. understanding changes in krill abundance has long been a priority for research and conservation in the southern ocean. in this study, we performed stable isotope analyses on ancient adélie penguin tissues and inferred relative krill abundance during the holocene epoch from paleodiets of adélie penguin (pygoscelis ... | 2013 | 24076768 |
| 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 ... | 2014 | 25671091 |
| 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 ( ... | 2017 | 28732330 |
| 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 ... | 2014 | 24333412 |
| 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 ... | 2016 | 26391440 |
| buoyancy and maximal diving depth in penguins: do they control inhaling air volume? | using a newly developed data logger to measure acceleration, we demonstrate that free-ranging king and adélie penguins only beat their flippers substantially during the first part of descent or when they were presumed to be chasing prey at the bottom of dives. flipper beating stopped during the latter part of ascent: at 29+/-9 % (mean +/- s.d.) of dive depth (mean dive depth=136.8+/-145.1 m, n=425 dives) in king penguins, and at 52+/-20 % of dive depth (mean dive depth=72.9+/-70.5 m, n=664 dives ... | 2002 | 11948196 |
| 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 ... | 2017 | 28493935 |
| 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 ... | 2013 | 23969993 |
| 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 ... | 2014 | 23795836 |
| 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. ... | 2013 | 23770271 |
| 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. ... | 2017 | 28356224 |
| 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 ... | 2017 | 28237525 |
| 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 ... | 2017 | 28129431 |
| 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 ... | 2016 | 26934698 |
| 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 ... | 2016 | 26909171 |
| 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. ... | 2016 | 26732496 |
| 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 ... | 2015 | 26577544 |
| distribution of metals and trace elements in adult and juvenile penguins from the antarctic peninsula area. | the presence of metals in the antarctic environment is principally a natural phenomenon caused by geochemical characteristics of the region, although some anthropogenic activities can increase these natural levels. antarctic penguins present several of the characteristics of useful sentinels of pollution in antarctica such as they are long-lived species situated at the top of food web. the concentrations of al, cr, mn, fe, ni, cu, zn, as, se, cd, and pb were determined by inductively coupled pla ... | 2013 | 23093414 |
| 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 ... | 2012 | 23069932 |
| spatially integrated assessment reveals widespread changes in penguin populations on the antarctic peninsula. | as 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 ... | 2012 | 22834377 |
| adélie penguins and temperature changes in antarctica: a long-term view. | during the summer months, adélie penguins represent the dominant biomass of terrestrial antarctica. literally millions of individuals nest in ice-free areas around the coast of the continent. hence, these modern populations of adélie penguins have often been championed as an ideal biological indicator of ecological and environmental changes that we currently face. in addition, adélie penguins show an extraordinary record of sub-fossil remains, dating back to the late pleistocene. at this time, t ... | 2012 | 22691195 |
| 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. | 2012 | 22302487 |
| 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 ... | 2015 | 26502059 |
| 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 ... | 2015 | 26392864 |
| 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 ... | 2015 | 26113152 |
| 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 ... | 2015 | 25487332 |
| 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 ... | 2014 | 25412466 |
| stable isotopes reveal holocene changes in the diet of adélie penguins in northern victoria land (ross sea, antarctica). | adélie penguin (pygoscelis adeliae) modern and fossil eggshells and guano samples collected from ornithogenic soils in terra nova bay (victoria land, ross sea) were processed for carbon and nitrogen isotopic ratios with the aim of detecting past penguin dietary changes. a detailed and greatly expanded adélie penguin dietary record dated back to 7,200 years bp has been reconstructed for the investigated area. our data indicate a significant dietary shift between fish and krill, with a gradual dec ... | 2010 | 20886238 |
| 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 ... | 2014 | 25157452 |
| 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 ... | 2014 | 25000452 |