Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| 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 |
| 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 |
| 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 |
| 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 |
| high mitogenomic evolutionary rates and time dependency. | using entire modern and ancient mitochondrial genomes of adélie penguins (pygoscelis adeliae) that are up to 44000 years old, we show that the rates of evolution of the mitochondrial genome are two to six times greater than those estimated from phylogenetic comparisons. although the rate of evolution at constrained sites, including nonsynonymous positions and rnas, varies more than twofold with time (between shallow and deep nodes), the rate of evolution at synonymous sites remains the same. the ... | 2009 | 19836098 |
| foraging in an oxidative environment: relationship between delta13c values and oxidative status in adelie penguins. | the alternation of short/coastal and long/pelagic foraging trips has been proposed as a strategy for seabirds to reconcile self-feeding and parental care. both types of foraging trips may result in different foraging efforts and diet qualities, and consequently are likely to modify the oxidative status of seabirds. we examined the relationship between the oxidative status of adélie penguins and (i) the duration of their foraging trips and (ii) their plasma delta(13)c values reflecting their spat ... | 2010 | 19955151 |
| ecophysiological response of adelie penguins facing an experimental increase in breeding constraints. | foraging strategies play a key role in breeding effort. little is known, however, about their connection with hormonal and nutritional states, especially when breeding constraints vary. here, we experimentally increased foraging costs and thus breeding constraints by handicapping adélie penguins (pygoscelis adeliae) with dummy devices representing 3-4% of the penguins' cross-sectional area. we examined food-related stress (via plasma corticosterone concentration) and nutritional state (via metab ... | 2010 | 20008359 |
| 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 |
| should i stay or should i go? hormonal control of nest abandonment in a long-lived bird, the adélie penguin. | according to life-history theory, long-lived birds should favor their survival over the current reproductive attempt, when breeding becomes too costly. in seabirds, incubation is often associated with spontaneous long-term fasting. below a threshold in body reserves, hormonal and metabolic shift characteristics of a switch from lipid to protein utilization (phase iii, piii) occur. these metabolic changes are paralleled by nest abandonment and stimulation of refeeding behavior. parental behavior ... | 2010 | 20691185 |
| working less to gain more: when breeding quality relates to foraging efficiency. | in animal populations, a minority of individuals consistently achieves the highest breeding success and therefore contributes the most recruits to future generations. on average, foraging performance is important in determining breeding success at the population level, but evidence is scarce to show that more successful breeders (better breeders) forage differently than less successful ones (poorer breeders). to test this hypothesis, we used a 10-year, three-colony, individual-based longitudinal ... | 2010 | 20715627 |
| 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 |
| contrasting time trends of organic contaminants in antarctic pelagic and benthic food webs. | we demonstrate that pelagic antarctic seabirds show significant decreases in concentrations of some persistent organic pollutants. trends in adélie penguins and southern fulmars fit in a general pattern revealed by a broad literature review. downward trends are also visible in pelagic fish, contrasting sharply with steady or increasing concentrations in antarctic benthic organisms. transfer of contaminants between antarctic pelagic and benthic food webs is associated with seasonal sea-ice dynami ... | 2011 | 20880557 |
| 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 |
| exogenous corticosterone mimics a late fasting stage in captive adelie penguins (pygoscelis adeliae). | fasting is part of penguin's breeding constraints. during prolonged fasting, three metabolic phases occur successively. below a threshold in body reserves, birds enter phase iii (piii), which is characterized by hormonal and metabolic shifts. these changes are concomitant with egg abandonment in the wild and increased locomotor activity in captivity. because corticosterone (cort) enhances foraging activity, we investigated the variations of endogenous cort, and the effects of exogenous cort on t ... | 2011 | 21346242 |
| autonomous gliders reveal features of the water column associated with foraging by adelie penguins. | despite their strong dependence on the pelagic environment, seabirds and other top predators in polar marine ecosystems are generally studied during their reproductive phases in terrestrial environments. as a result, a significant portion of their life history is understudied which in turn has led to limited understanding. recent advances in autonomous underwater vehicle (auv) technologies have allowed satellite-tagged adélie penguins to guide auv surveys of the marine environment at the palmer ... | 2010 | 21558258 |
| 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 |
| environmental influences on adelie penguin breeding schedules, endocrinology, and chick survival. | to understand how the social and physical environment influences behaviour, reproduction and survival, studies of underlying hormonal processes are crucial; in particular, interactions between stress and reproductive responses may have critical influences on breeding schedules. several authors have examined the timing of breeding in relation to environmental stimuli, while others have independently described endocrine profiles. however, few studies have simultaneously measured endocrine profiles ... | 2011 | 21624370 |
| adélie penguin survival: age structure, temporal variability and environmental influences. | the driving factors of survival, a key demographic process, have been particularly challenging to study, especially for winter migratory species such as the adélie penguin (pygoscelis adeliae). while winter environmental conditions clearly influence antarctic seabird survival, it has been unclear to which environmental features they are most likely to respond. here, we examine the influence of environmental fluctuations, broad climatic conditions and the success of the breeding season prior to w ... | 2011 | 21691857 |
| 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 |
| physiological condition and reproductive consequences in adelie penguins. | animals must make "decisions" (e.g., when or whether to breed, the effort to put into a breeding episode) by integrating physiological, environmental and social inputs. this integration can be studied only in a field context. in adélie penguins (pygoscelis adeliae) reproduction is constrained by foraging ecology, mode of transport, and the extreme latitude at which they live. the decision whether to breed in a given year is influenced by body conditions. adélie penguins must fast for several wee ... | 2002 | 21708696 |
| exogenous corticosterone and nest abandonment: a study in a long-lived bird, the adélie penguin. | breeding individuals enter an emergency life-history stage when their body reserves reach a minimum threshold. consequently, they redirect current activity toward survival, leading to egg abandonment in birds. corticosterone (cort) is known to promote this stage. how and to what extent cort triggers egg abandonment when breeding is associated with prolonged fasting, however, requires further investigation. we manipulated free-living male adélie penguins with cort-pellets before their laying peri ... | 2011 | 21763694 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| elevated corticosterone levels and severe weather conditions decrease parental investment of incubating adélie penguins. | corticosterone, the main stress hormone in birds, mediates resource allocation, allowing animals to adjust their physiology and behaviour to changes in the environment. incubation is a time and energy-consuming phase of the avian reproductive cycle. it may be terminated prematurely, when the parents' energy stores are depleted or when environmental conditions are severe. in this study, the effects of experimentally elevated baseline corticosterone levels on the parental investment of incubating ... | 2013 | 23291423 |
| linking animal-borne video to accelerometers reveals prey capture variability. | understanding foraging is important in ecology, as it determines the energy gains and, ultimately, the fitness of animals. however, monitoring prey captures of individual animals is difficult. direct observations using animal-borne videos have short recording periods, and indirect signals (e.g., stomach temperature) are never validated in the field. we took an integrated approach to monitor prey captures by a predator by deploying a video camera (lasting for 85 min) and two accelerometers (on th ... | 2013 | 23341596 |
| adélie penguin foraging location predicted by tidal regime switching. | penguin foraging and breeding success depend on broad-scale environmental and local-scale hydrographic features of their habitat. we investigated the effect of local tidal currents on a population of adélie penguins on humble is., antarctica. we used satellite-tagged penguins, an autonomous underwater vehicle, and historical tidal records to model of penguin foraging locations over ten seasons. the bearing of tidal currents did not oscillate daily, but rather between diurnal and semidiurnal tida ... | 2013 | 23383091 |
| 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 |
| monitoring trace elements in antarctic penguin chicks from south shetland islands, antarctica. | the concentration of human activities in the near-shore ecosystems from the northern antarctic peninsula area can cause an increasing bioavailability of pollutants for the vulnerable antarctic biota. penguin chicks can reflect this potential impact in the rookeries during the breeding season. they also can reflect biomagnification phenomena since they are on the top of the antarctic food chain. the concentrations of al, cr, mn, fe, ni, cu, zn, as, se, cd and pb were measured by icp-ms in samples ... | 2013 | 23465574 |
| climate change winners: receding ice fields facilitate colony expansion and altered dynamics in an adélie penguin metapopulation. | there will be winners and losers as climate change alters the habitats of polar organisms. for an adélie penguin (pygoscelis adeliae) colony on beaufort island (beaufort), part of a cluster of colonies in the southern ross sea, we report a recent population increase in response to increased nesting habitat as glaciers have receded. emigration rates of birds banded as chicks on beaufort to colonies on nearby ross island decreased after 2005 as available habitat on beaufort increased, leading to a ... | 2013 | 23573267 |
| 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 |
| 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 |
| 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 |
| trophic calculations reveal the mechanism of population-level variation in mercury concentrations between marine ecosystems: case studies of two polar seabirds. | the incorporation of quantitative trophic level analysis in ecotoxicological studies provides explanatory power to identify the factors, trophic or environmental, driving population-level variation in mercury exposure at large geographic scales. in the antarctic marine ecosystem, mercury concentrations and stable isotope values in adélie penguins (pygoscelis adeliae) were compared between the antarctic peninsula and the ross sea. correcting tissue δ(15)n values for baseline δ(15)n values reveale ... | 2013 | 23993395 |
| ontogeny of muscle bioenergetics in adelie penguin chicks (pygoscelis adeliae). | the ontogeny of pectoralis muscle bioenergetics was studied in growing adélie penguin chicks during the first month after hatching and compared with adults using permeabilized fibers and isolated mitochondria. with pyruvate-malate-succinate or palmitoyl-carnitine as substrates, permeabilized fiber respiration markedly increased during chick growth (3-fold) and further rose in adults (1.4-fold). several markers of muscle fiber oxidative activity (cytochrome oxidase, citrate synthase, hydroxyl-acy ... | 2013 | 24005252 |
| growth prior to thermogenesis for a quick fledging of adélie penguin chicks (pygoscelis adeliae). | the evolutionary trade-off between tissue growth and mature function restricts the post natal development of polar birds. the present study uses an original integrative approach as it includes gene expression, plus biochemical and physiological analysis to investigate how adélie penguin chicks achieve a rapid growth despite the energetic constraints linked to the cold and the very short breeding season in antarctica. in pectoralis muscle, the main thermogenic tissue in birds, our data show that ... | 2013 | 24040194 |
| 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 |
| 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 |
| adélie penguin population diet monitoring by analysis of food dna in scats. | the adélie penguin is the most important animal currently used for ecosystem monitoring in the southern ocean. the diet of this species is generally studied by visual analysis of stomach contents; or ratios of isotopes of carbon and nitrogen incorporated into the penguin from its food. there are significant limitations to the information that can be gained from these methods. we evaluated population diet assessment by analysis of food dna in scats as an alternative method for ecosystem monitorin ... | 2013 | 24358158 |
| 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 |
| testing optimal foraging theory in a penguin-krill system. | food is heterogeneously distributed in nature, and understanding how animals search for and exploit food patches is a fundamental challenge in ecology. the classic marginal value theorem (mvt) formulates optimal patch residence time in response to patch quality. the mvt was generally proved in controlled animal experiments; however, owing to the technical difficulties in recording foraging behaviour in the wild, it has been inadequately examined in natural predator-prey systems, especially those ... | 2014 | 24478293 |
| antarctic climate change: extreme events disrupt plastic phenotypic response in adélie penguins. | in the context of predicted alteration of sea ice cover and increased frequency of extreme events, it is especially timely to investigate plasticity within antarctic species responding to a key environmental aspect of their ecology: sea ice variability. using 13 years of longitudinal data, we investigated the effect of sea ice concentration (sic) on the foraging efficiency of adélie penguins (pygoscelis adeliae) breeding in the ross sea. a 'natural experiment' brought by the exceptional presence ... | 2014 | 24489657 |
| 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 |
| a novel papillomavirus in adélie penguin (pygoscelis adeliae) faeces sampled at the cape crozier colony, antarctica. | papillomaviruses are epitheliotropic viruses that have circular dsdna genomes encapsidated in non-enveloped virions. they have been found to infect a variety of mammals, reptiles and birds, but so far they have not been found in amphibians. using a next-generation sequencing de novo assembly contig-informed recovery, we cloned and sanger sequenced the complete genome of a novel papillomavirus from the faecal matter of adélie penguins (pygoscelis adeliae) nesting on ross island, antarctica. the g ... | 2014 | 24686913 |
| have historical climate changes affected gentoo penguin (pygoscelis papua) populations in antarctica? | the west antarctic peninsula (wap) has been suffering an increase in its atmospheric temperature during the last 50 years, mainly associated with global warming. this increment of temperature trend associated with changes in sea-ice dynamics has an impact on organisms, affecting their phenology, physiology and distribution range. for instance, rapid demographic changes in pygoscelis penguins have been reported over the last 50 years in wap, resulting in population expansion of sub-antarctic gent ... | 2014 | 24759777 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| two antarctic penguin genomes reveal insights into their evolutionary history and molecular changes related to the antarctic environment. | penguins are flightless aquatic birds widely distributed in the southern hemisphere. the distinctive morphological and physiological features of penguins allow them to live an aquatic life, and some of them have successfully adapted to the hostile environments in antarctica. to study the phylogenetic and population history of penguins and the molecular basis of their adaptations to antarctica, we sequenced the genomes of the two antarctic dwelling penguin species, the adélie penguin [pygoscelis ... | 2014 | 25671092 |
| penguin lungs and air sacs: implications for baroprotection, oxygen stores and buoyancy. | the anatomy and volume of the penguin respiratory system contribute significantly to pulmonary baroprotection, the body o2 store, buoyancy and hence the overall diving physiology of penguins. therefore, three-dimensional reconstructions from computerized tomographic (ct) scans of live penguins were utilized to measure lung volumes, air sac volumes, tracheobronchial volumes and total body volumes at different inflation pressures in three species with different dive capacities [adélie (pygoscelis ... | 2015 | 25740902 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| integrating oxidative ecology into conservation physiology. | ecologists have recently shown great interest in using physiological markers as indicators of the health of animal populations. in this context, the measurement of markers of oxidative balance, such as antioxidant defences and oxidative damage, may be a valuable tool. indeed, at the individual level, antioxidant defences are positively associated with fertility and survival probability, while elevated oxidative damage during reproduction or growth may negatively affect recruitment and survival. ... | 2013 | 27293588 |
| elevated corticosterone levels decrease reproductive output of chick-rearing adélie penguins but do not affect chick mass at fledging. | study of physiological mechanisms can help us to understand how animals respond to changing environmental conditions. in particular, stress hormones (i.e. glucocorticoids, such as corticosterone) are described as mediating resource allocation, allowing animals to adjust their physiology and behaviour to predictable and unpredictable changes in the environment. in this study, we investigated the effects of an experimental increase in baseline corticosterone levels on the breeding effort and the r ... | 2013 | 27293591 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| weather, microclimate, and energy costs of thermoregulation for breeding adélie penguins. | we measured meteorological conditions and estimated the energy costs of thermoregulation for young and adult adélie penguins (pygoscelis adeliae) at a breeding colony near the antarctic peninsula. air temperatures averaged < 5°c and strong winds were frequent. operative temperatures (te) for adults ranged from -8 to 28°c, averaging 5-6°c, for the period from courtship to fledging of chicks. the average energy cost of thermoregulation (cth) for adult penguins was equivalent to 10-16% of basal met ... | 1990 | 28313017 |
| 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 |
| 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 |
| 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 |
| pan-antarctic analysis aggregating spatial estimates of adélie penguin abundance reveals robust dynamics despite stochastic noise. | colonially-breeding seabirds have long served as indicator species for the health of the oceans on which they depend. abundance and breeding data are repeatedly collected at fixed study sites in the hopes that changes in abundance and productivity may be useful for adaptive management of marine resources, but their suitability for this purpose is often unknown. to address this, we fit a bayesian population dynamics model that includes process and observation error to all known adélie penguin abu ... | 2017 | 29018199 |
| aerial photography based census of adélie penguin and its application in ch4 and n2o budget estimation in victoria land, antarctic. | penguin guano provides favorable conditions for production and emission of greenhouse gases (ghgs). many studies have been conducted to determine the ghg fluxes from penguin colonies, however, at regional scale, there is still no accurate estimation of total ghg emissions. we used object-based image analysis (obia) method to estimate the adélie penguin (pygoscelis adeliae) population based on aerial photography data. a model was developed to estimate total ghg emission potential from adélie peng ... | 2017 | 29021539 |
| unique genome organization of non-mammalian papillomaviruses provides insights into the evolution of viral early proteins. | the familypapillomaviridaecontains more than 320 papillomavirus types, with most having been identified as infecting skin and mucosal epithelium in mammalian hosts. to date, only nine non-mammalian papillomaviruses have been described from birds (n = 5), a fish (n = 1), a snake (n = 1), and turtles (n = 2). the identification of papillomaviruses in sauropsids and a sparid fish suggests that early ancestors of papillomaviruses were already infecting the earliest euteleostomi. the euteleostomi cla ... | 2017 | 29026649 |
| rethinking "normal": the role of stochasticity in the phenology of a synchronously breeding seabird. | phenological changes have been observed in a variety of systems over the past century. there is concern that, as a consequence, ecological interactions are becoming increasingly mismatched in time, with negative consequences for ecological function. significant spatial heterogeneity (inter-site) and temporal variability (inter-annual) can make it difficult to separate intrinsic, extrinsic and stochastic drivers of phenological variability. the goal of this study was to understand the timing and ... | 2017 | 29277890 |
| landscape genomics: natural selection drives the evolution of mitogenome in penguins. | mitochondria play a key role in the balance of energy and heat production, and therefore the mitochondrial genome is under natural selection by environmental temperature and food availability, since starvation can generate more efficient coupling of energy production. however, selection over mitochondrial dna (mtdna) genes has usually been evaluated at the population level. we sequenced by ngs 12 mitogenomes and with four published genomes, assessed genetic variation in ten penguin species distr ... | 2018 | 29338715 |
| multi-modal survey of adélie penguin mega-colonies reveals the danger islands as a seabird hotspot. | despite concerted international effort to track and interpret shifts in the abundance and distribution of adélie penguins, large populations continue to be identified. here we report on a major hotspot of adélie penguin abundance identified in the danger islands off the northern tip of the antarctic peninsula (ap). we present the first complete census of pygoscelis spp. penguins in the danger islands, estimated from a multi-modal survey consisting of direct ground counts and computer-automated c ... | 2018 | 29500389 |
| time-lapse imagery of adélie penguins reveals differential winter strategies and breeding site occupation. | polar seabirds adopt different over-wintering strategies to survive and build condition during the critical winter period. penguin species either reside at the colony during the winter months or migrate long distances. tracking studies and survey methods have revealed differences in winter migration routes among penguin species and colonies, dependent on both biotic and abiotic factors present. however, scan sampling methods are rarely used to reveal non-breeding behaviors during winter and litt ... | 2018 | 29561876 |
| 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 ... | 2018 | 29686847 |
| genomic insights into natural selection in the common loon (gavia immer): evidence for aquatic adaptation. | the common loon (gavia immer) is one of five species that comprise the avian order gaviiformes. loons are specialized divers, reaching depths up to 60 m while staying submerged for intervals up to three minutes. in this study we used comparative genomics to investigate the genetic basis of the common loon adaptations to its ecological niche. we used illumina short read dna sequence data from a female bird to produce a draft assembly of the common loon (gavia immer) genome. | 2018 | 29703132 |
| 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 ... | 2018 | 29722905 |
| the rise and fall of an ancient adélie penguin 'supercolony' at cape adare, antarctica. | we report new discoveries and radiocarbon dates on active and abandoned adélie penguin (pygoscelis adeliae) colonies at cape adare, antarctica. this colony, first established at approximately 2000 bp (calendar years before present, i.e. 1950), is currently the largest for this species with approximately 338 000 breeding pairs, most located on low-lying ridley beach. we hypothesize that this colony first formed after fast ice began blocking open-water access by breeding penguins to the scott coas ... | 2018 | 29765656 |
| nasal mites (mesostigmata: rhinonyssidae) in african penguins (spheniscus demersus). | rhinonyssids are obligate haematophagous mites that parasitize the nasal cavity of vertebrates, and occur in a wide range of birds worldwide. two species of nasal mites are known to occur in penguins: rhinonyssus sphenisci, which has been recorded from humboldt and magellanic penguins (spheniscus humboldti and s. magellanicus, respectively), and rhinonyssus schelli, which has been recorded in adélie and gentoo penguins (pygoscelis adeliae and p. papua, respectively). we examined the nasal cavity ... | 2019 | 29921335 |