| population response of an apex antarctic consumer to its prey and climate fluctuations. | a fundamental endeavor in population ecology is to identify the drivers of population dynamics. a few empirical studies included the effect of prey abundance when investigating simultaneously the effects of density-dependence and climate factors on marine top-predator population dynamics. our aim was to unravel the mechanisms forcing population dynamics of an apex consumer seabird, the south polar skua, using long-term climatic and population time series of the consumer and its prey in terre adé ... | 2019 | 30116877 |
| identification and distribution of novel cressdnaviruses and circular molecules in four penguin species in south georgia and the antarctic peninsula. | there is growing interest in uncovering the viral diversity present in wild animal species. the remote antarctic region is home to a wealth of uncovered microbial diversity, some of which is associated with its megafauna, including penguin species, the dominant avian biota. penguins interface with a number of other biota in their roles as marine mesopredators and several species overlap in their ranges and habitats. to characterize the circular single-stranded viruses related to those in the phy ... | 2020 | 32947826 |
| 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 |
| counting penguins with drones. | a multidrone path-planning algorithm enables drones to scout adélie penguin colonies in antarctica. | 2020 | 33115885 |
| multidrone aerial surveys of penguin colonies in antarctica. | speed is essential in wildlife surveys due to the dynamic movement of animals throughout their environment and potentially extreme changes in weather. in this work, we present a multirobot path-planning method for conducting aerial surveys over large areas designed to make the best use of limited flight time. unlike current survey path-planning solutions based on geometric patterns or integer programs, we solve a series of satisfiability modulo theory instances of increasing complexity. each ins ... | 2020 | 33115884 |
| 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 |
| antarctic adélie penguin feathers as bio-indicators of geographic and temporal variations in heavy metal concentrations in their habitats. | seabird feathers are effective indicators of heavy metal contamination. to propose a biological detection method suitable for the long-term monitoring of heavy metals in the antarctic environment, eight heavy metals (as, cd, cr, cu, hg, ni, pb, and zn) in adélie penguin feathers from different body parts, years, and molting grounds in the antarctic were investigated in this study. it is found that the concentrations of heavy metals in the feathers showed differences among the body part of origin ... | 2020 | 32866890 |
| a smelly business: microbiology of adélie penguin guano (point thomas rookery, antarctica). | adélie penguins (pygoscelis adeliae) are the most numerous flightless bird group breeding in coastal areas of maritime and continental antarctica. their activity leaves a mark on the land in the form of large guano deposits. this guano is an important nutrient source for terrestrial habitats of ice-free antarctic areas, most notably by being the source of ammonia vapors which feed the surrounding grass, lichen and algae communities. although investigated by researchers, the fate of the guano-ass ... | 2020 | 31978775 |
| application of δ15n to trace the impact of penguin guano on terrestrial and aquatic nitrogen cycles in victoria land, ross sea region, antarctica. | penguin colonies in antarctica offer an ideal "natural laboratory" to investigate ecosystem function and the nitrogen (n) cycle. this study assessed the spatial distribution of penguin-derived n from guano and quantitatively assessed its impact on plant n utilization strategies in victoria land, ross sea region, antarctica. soil, moss, and aquatic microbial mats were collected inside and outside an active adélie penguin (pygoscelis adeliae) colony and analyzed for δ15n of total and inorganic nit ... | 2020 | 31874340 |
| identification of a novel adélie penguin circovirus at cape crozier (ross island, antarctica). | understanding the causes of disease in antarctic wildlife is crucial, as many of these species are already threatened by environmental changes brought about by climate change. in recent years, antarctic penguins have been showing signs of an unknown pathology: a feather disorder characterised by missing feathers, resulting in exposed skin. during the 2018-2019 austral summer breeding season at cape crozier colony on ross island, antarctica, we observed for the first time an adélie penguin chick ... | 2019 | 31766719 |
| identification of circovirus genome in a chinstrap penguin (pygoscelis antarcticus) and adélie penguin (pygoscelis adeliae) on the antarctic peninsula. | circoviruses infect a variety of animal species and have small (~1.8-2.2 kb) circular single-stranded dna genomes. recently a penguin circovirus (pencv) was identified associated with an adélie penguin (pygoscelis adeliae) with feather disorder and in the cloacal swabs of three asymptomatic adélie penguins at cape crozier, antarctica. a total of 75 cloacal swab samples obtained from adults and chicks of three species of penguin (genus: pygoscelis) from seven antarctic breeding colonies (south sh ... | 2020 | 32781620 |
| biological factors affecting total mercury and methylmercury levels in antarctic penguins. | penguins in antarctica occupy high trophic levels, thus accumulating high amounts of mercury (hg) through bioaccumulation and biomagnification. blood reflects the current levels of contaminants circulating in the body, while feathers are known as the main route of hg elimination in birds. studies sampling chicks and adults can provide a comprehensive picture of bioaccumulation and local contamination. three pygoscelid species (pygoscelis adeliae, pygoscelis antarcticus and pygoscelis papua) have ... | 2020 | 32738710 |
| nonbreeder birds at colonies display qualitatively similar seasonal mass change patterns as breeders. | the difficulty in studying nonbreeding birds means that little is known about them or their resource requirements, despite forming a large and significant component of a population. one way to assess food requirements is to examine changes in body mass, because it indicates the amount of food acquired. in terms of body mass changes, our expectation is that nonbreeders will either (a) be in poorer condition than the breeders which potentially explains why they do not breed or (b) remain at a stab ... | 2019 | 31031932 |
| evidence of age-related improvement in the foraging efficiency of adélie penguins. | age variation in reproductive performance is well-documented but the mechanisms underlying this variation remain unclear. foraging efficiency is likely to be a key source of demographic variation as it determines the amount of energy that can be invested in fitness-related activities. evidence of age-related changes in the foraging efficiency of adult seabirds is scarce and inconsistent. we investigated the effects of age on the foraging efficiency of breeding adélie penguins, a relatively short ... | 2019 | 30833598 |
| central place foragers select ocean surface convergent features despite differing foraging strategies. | discovering the predictors of foraging locations can be challenging, and is often the critical missing piece for interpreting the ecological significance of observed movement patterns of predators. this is especially true in dynamic coastal marine systems, where planktonic food resources are diffuse and must be either physically or biologically concentrated to support upper trophic levels. in the western antarctic peninsula, recent climate change has created new foraging sympatry between adélie ... | 2019 | 30655549 |
| density dependence forces divergent population growth rates and alters occupancy patterns of a central place foraging antarctic seabird. | density-dependent regulation is an important process in spatio-temporal population dynamics because it can alter the effects of synchronizing processes operating over large spatial scales. most frequently, populations are regulated by density dependence when higher density leads to reduced individual fitness and population growth, but inverse density dependence can also occur when small populations are subject to higher extinction risks. we investigate whether density-dependent regulation influe ... | 2020 | 32184985 |
| spatial niche partitioning may promote coexistence of pygoscelis penguins as climate-induced sympatry occurs. | climate-induced range overlap can result in novel interactions between similar species and potentially lead to competitive exclusion. the west antarctic peninsula (wap) is one of the most rapidly warming regions on earth and is experiencing a poleward climate migration from a polar to subpolar environment. this has resulted in a range expansion of the ice-intolerant gentoo penguins (pygoscelis papua) and a coincident decrease in ice-obligate adélie penguins (p. adeliae) near palmer station, anve ... | 2018 | 30386573 |
| reproductive performance and diving behaviour share a common sea-ice concentration optimum in adélie penguins (pygoscelis adeliae). | the southern ocean is currently experiencing major environmental changes, including in sea-ice cover. such changes strongly influence ecosystem structure and functioning and affect the survival and reproduction of predators such as seabirds. these effects are likely mediated by reduced availability of food resources. as such, seabirds are reliable eco-indicators of environmental conditions in the antarctic region. here, based on 9 years of sea-ice data, we found that the breeding success of adél ... | 2018 | 29957836 |
| 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 |
| the interaction between island geomorphology and environmental parameters drives adélie penguin breeding phenology on neighboring islands near palmer station, antarctica. | despite many studies on adélie penguin breeding phenology, understanding the drivers of clutch initiation dates (cids, egg 1 lay date) is limited or lacks consensus. here, we investigated adélie penguin cids over 25 years (1991-2016) on two neighboring islands, torgersen and humble (<1 km apart), in a rapidly warming region near palmer station, antarctica. we found that sea ice was the primary large-scale driver of cids and precipitation was a secondary small-scale driver that fine-tunes cid to ... | 2019 | 31463025 |
| novel penguin avian avulaviruses 17, 18 and 19 are widely distributed in the antarctic peninsula. | three novel avian avulavirus species were discovered and isolated during 2017 from gentoo penguins (pygoscelis papua) at kopaitic island in the northwestern region of the antarctic peninsula. the viruses were officially named as avian avulavirus 17 (aav17), avian avulavirus 18 (aav18) and avian avulavirus 19 (aav19), collectively referred to as penguin avulaviruses (pavs). to determine whether these viruses are capable of infecting the three species of pygoscelis spp. penguins (gentoo, adelie an ... | 2019 | 31355981 |
| 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 |
| when the "selfish herd" becomes the "frozen herd": spatial dynamics and population persistence in a colonial seabird. | aggregations are common in ecological systems at a range of scales and may be driven by exogenous constraints such as environmental heterogeneity and resource availability or by "self-organizing" interactions among individuals. one mechanism leading to self-organized animal aggregations is captured by hamilton's "selfish herd" hypothesis, which suggests that aggregations may be driven by an individual's effort to minimize their risk of predation by surrounding themselves with conspecifics. we de ... | 2019 | 31310664 |
| pingu virus: a new picornavirus in penguins from antarctica. | picornaviridae family comprises single-stranded, positive-sense rna viruses distributed into forty-seven genera. picornaviruses have a broad host range and geographic distribution in all continents. in this study, we applied a high-throughput sequencing approach to examine the presence of picornaviruses in penguins from king george island, antarctica. we discovered and characterized a novel picornavirus from cloacal swab samples of gentoo penguins (pygoscelis papua), which we tentatively named p ... | 2019 | 31850147 |
| 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 |
| comparative population genomics reveals key barriers to dispersal in southern ocean penguins. | the mechanisms that determine patterns of species dispersal are important factors in the production and maintenance of biodiversity. understanding these mechanisms helps to forecast the responses of species to environmental change. here, we used a comparative framework and genomewide data obtained through rad-seq to compare the patterns of connectivity among breeding colonies for five penguin species with shared ancestry, overlapping distributions and differing ecological niches, allowing an exa ... | 2018 | 30308702 |
| adélie penguin colonies as indicators of brominated flame retardants (bfrs) in east antarctica. | while persistent organic pollutant (pop) contamination within antarctica is largely caused by long-range atmospheric transport (lrat), antarctic research bases have been shown to be local sources of pops such as brominated flame retardants (bfrs). this study compared concentrations of seven polybrominated diphenyl ethers (pbde) congeners and five novel flame retardants (nbfrs) found in adélie penguin (pygoscelis adeliae) colony soils near the australian research stations, mawson and davis, to as ... | 2020 | 32126331 |
| 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 |
| 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 |
| 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 |
| 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 |
| health surveillance of penguins in the barton peninsula on king george island, antarctica. | samples from 29 adult gentoo (pygoscelis papua), chinstrap (pygoscelis antarcticus), and adélie penguins (pygoscelis adeliae) at the king sejong station on nar̢ ebski point, king george island, antarctica, were investigated to detect antibodies to avian influenza, newcastle disease virus, infectious bursal disease virus, infectious bronchitis virus, mycoplasma, and salmonella. antibodies were identified from one gentoo penguin and one chinstrap penguin against infectious bronchitis virus; from o ... | 2021 | 33872350 |
| avian orthoavulavirus 1 (newcastle disease virus) antibodies in five penguin species, antarctic peninsula and southern patagonia. | avian orthoavulavirus 1 (aoav-1) causes newcastle disease, one of the most important and contagious infections in poultry, where migratory birds can play a key role as a reservoir. seven hundred and seven serum samples were collected from five penguin species (king, magellanic, gentoo, chinstrap and adelie penguins) in the antarctic and sub-antarctic zones. using a competitive elisa to detect antibodies against aoav-1, we identified positive individuals in all penguin species. the magellanic pen ... | 2021 | 33587778 |