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mortality of a juvenile magellanic penguin (spheniscus magellanicus, spheniscidae) associated with the ingestion of a pff-2 protective mask during the covid-19 pandemic.we report the discovery of a dead magellanic penguin (spheniscus magellanicus) found on juquehy beach (23°46's 45°44'w), municipality of são sebastião, brazil, on september 9th 2020. following necropsy, we noted the presence of an adult size pff-2 protective mask within the stomach of the penguin which we inferred as the cause of death. as far as we are aware, this is the first recorded instance of marine animal mortality by protective face mask ingestion. whilst concerns have been raised relati ...202133725563
avian orthoavulavirus 1 (newcastle disease virus) antibodies in five penguin species, antarctic peninsula and southern patagonia.avian orthoavulavirus 1 (aoav-1) causes newcastle disease, one of the most important and contagious infections in poultry, where migratory birds can play a key role as a reservoir. seven hundred and seven serum samples were collected from five penguin species (king, magellanic, gentoo, chinstrap and adelie penguins) in the antarctic and sub-antarctic zones. using a competitive elisa to detect antibodies against aoav-1, we identified positive individuals in all penguin species. the magellanic pen ...202133587778
phylogenetic relationships of cardiocephaloides spp. (digenea, diplostomoidea) and the genetic characterization of cardiocephaloides physalis from magellanic penguin, spheniscus magellanicus, in chile.cardiocephaloides is a small genus of strigeid digeneans with an essentially cosmopolitan distribution. most members of cardiocephaloides are found in larid birds, however, cardiocephaloides physalis is an exception and parasitizes penguins in some coastal regions of south america and south africa. no prior molecular phylogenetic studies have included dna sequence data of c. physalis. herein, we provide molecular phylogenetic analyses of cardiocephaloides using dna sequences from five species of ...202031919798
the role of demographic history and selection in shaping genetic diversity of the galápagos penguin (spheniscus mendiculus).although many studies have documented the effects of demographic bottlenecks on the genetic diversity of natural populations, there is conflicting evidence of the roles that genetic drift and selection may play in driving changes in genetic variation at adaptive loci. we analyzed genetic variation at microsatellite and mitochondrial loci in conjunction with an adaptive mhc class ii locus in the galápagos penguin (spheniscus mendiculus), a species that has undergone serial demographic bottlenecks ...202031910443
sex ratio is variable and increasingly male biased at two colonies of magellanic penguins.sex ratios are commonly skewed and variable in wild populations, but few studies track temporal trends in this demographic parameter. we examined variation in the operational sex ratio at two protected and declining breeding colonies of magellanic penguins (spheniscus magellanicus) in chubut, argentina. penguins from the two colonies, separated by 105 km, migrate north in the non-breeding season and have overlapping distributions at sea. conditions during the non-breeding season can impact long- ...202031746460
genetic evidence of hybridization between magellanic (sphensicus magellanicus) and humboldt (spheniscus humboldti) penguins in the wild.the process of hybridization between closely related species plays an important role in defining the genetic integrity and overall genetic diversity of species. the distribution range of magellanic (spheniscus magellanicus) and humboldt (spheniscus humboldti) penguins is predominantly allopatric; however, the species share a region of sympatry where they may hybridize. we analyzed four types of genetic markers (including nuclear and mitochondrial markers) to assess their utility in detecting hyb ...202033070222
occurrence and tissue distribution of organochlorinated compounds and polycyclic aromatic hydrocarbons in magellanic penguins (spheniscus magellanicus) from the southeastern coast of brazil.seabirds are suitable biomonitors for several persistent organic pollutants (pop), such as polychlorinated biphenyls (pcbs), organochlorine pesticides (ocps) and polycyclic aromatic hydrocarbons (pahs), although scarce studies of pahs in seabirds are available, especially in south american populations. therefore, this study aimed to assess ocps, pcbs and pahs, through gas chromatography-electron capture detector (gc-ecd) and gas chromatography-mass spectrometry (gc-ms) analyses, in liver (n = 9) ...202032836122
enterococci from wild magellanic penguins (spheniscus magellanicus) as an indicator of marine ecosystem health and human impact.enterococci are commensals that proliferated as animals crawled ashore hundreds of millions of years ago. they are also leading causes of multidrug-resistant hospital-acquired infections. while most studies are driven by clinical interest, comparatively little is known about enterococci in the wild or the effect of human activity on them. pharmaceutical pollution and runoff from other human activities are encroaching widely into natural habitats. to assess their reach into remote habitats, we in ...202032737129
bioavailability of polycyclic aromatic hydrocarbons to penguins on the coast of southeastern brazil.bioavailability of polycyclic aromatic hydrocarbons on são paulo state coast (southeastern brazil) was evaluated through the analysis of biliary metabolites in spheniscus magellanicus (n = 79). the animals analyzed in present study were either found dead during beach monitoring procedures or died at rehabilitation centers. analyses of naphthalene (nap), phenanthrene (phe) and benzo[a]pyrene (bap) metabolites were performed using a high-performance liquid chromatograph equipped with fluorescence ...202032658674
compound-specific stable isotope analyses in falkland islands seabirds reveal seasonal changes in trophic positions.while nitrogen and carbon stable isotope values can reflect ecological segregation, prey choice and spatial distribution in seabirds, the interpretation of bulk stable isotope values is frequently hampered by a lack of isotopic baseline data. in this study, we used compound-specific isotope analyses of amino acids (csia-aa) to overcome this constraint and to study interspecific differences, seasonal and historical changes in trophic positions of five seabird species, three penguins and two petre ...202032293412
serological survey for select infectious agents in wild magellanic penguins (spheniscus magellanicus) in argentina, 1994-2008.despite being the most numerous penguin species in south america, exposure of the magellanic penguin (spheniscus magellanicus) to pathogens has not yet been thoroughly assessed. we collected serum from 1,058 magellanic penguins at 10 breeding colonies along the entire latitudinal range of this species in argentina. the work spanned 10 breeding seasons over 15 yr (1994-2008). sera were tested for antibodies to select infectious agents. antibodies reacting against 16 pathogens were detected (serop ...202031237822
diet-tissue discrimination factors (δ15 n and δ13 c values) for blood components in magellanic (spheniscus magellanicus) and southern rockhopper (eudyptes chrysocome) penguins.analysis of the stable isotope ratios of carbon and nitrogen (δ13 c and δ15 n values) is increasingly being used to gain insight into predator trophic ecology, which requires accurate diet-tissue discrimination factors (dtdfs), or the isotopic difference between prey and predator. accurate dtdfs must be calculated from predators consuming an isotopically constant diet over time in controlled feeding experiments, but these studies have received little attention to date, especially among seabird s ...202031657501
penguins are competent hosts of haemoproteus parasites: the first detection of gametocytes, with molecular characterization of haemoproteus larae.the majority of penguins (sphenisciformes) have evolved in areas with weak or absent transmission of haemosporidian parasites and are usually naïve to avian haemosporidian infections. plasmodium parasites are transmitted by mosquitoes, and lethal avian malaria has been often reported in captive penguins in many countries. the related haemosporidian parasites belonging to haemoproteus and leucocytozoon have also been detected in penguins but less often than plasmodium infections. the majority of ...202032532316
postmortem findings in magellanic penguins (spheniscus magellanicus) caught in a drift gillnet.penguin interaction with gillnets has been extensively reported in the atlantic and pacific oceans, and is considered a major conservation threat. among penguin species, magellanic penguins (spheniscus magellanicus) are currently considered of great concern, particularly in brazil, where they are highly susceptible to gillnet bycatch. nevertheless, information about drowning-associated microscopic findings in penguins is limited.202032448250
atrophic proventriculitis associated with gravid females of tetrameres sp. (nematoda: tetrameridae) in the magellanic penguin (spheniscus magellanicus) on the coast of brazil.the present study offers the first description of proventriculitis associated with the presence of gravid female nematodes of the genus tetrameres (nematoda: tetrameridae) in 3 juvenile magellanic penguins (spheniscus magellanicus) found dead on the coast of brazil. this study broadens knowledge on parasites associated with these hosts and the real impact of this association.202032083984
hematology and plasma chemistry values in beached magellanic penguin (spheniscus magellanicus) in northern argentina during the nonbreeding season.seabirds have been widely used for monitoring the health of the oceans in diverse marine regions. among low-cost survey strategies, systematic surveys of seabirds beached on coasts have been developed since the 20th century. however, these studies do not always address blood aspects. the assessment of the health status of birds based on the analysis of hematological and plasma chemistry is crucial to evaluate the overall health status profile of live organisms. here, the authors study the variab ...202031926525
genetic diversity and phylogeography of corynosoma australe johnston, 1937 (acanthocephala: polymorphidae), an endoparasite of otariids from the americas in the northern and southern hemispheres.adult specimens of corynosoma australe johnston, 1937 were recorded from the intestines of california sea lions, zalophus californianus (lesson), from baja california peninsula, mexico, whereas larval forms were collected from two fish species on the argentinian coast. adult specimens of c. australe were morphologically characterized by having a cylindrical proboscis with 18-20 rows of 12-14 hooks per row and a cylindrical trunk expanded anteriorly into a disk with tiny, triangular spines spread ...202033045410
lateralization (handedness) in magellanic penguins.lateralization, or asymmetry in form and/or function, is found in many animal species. brain lateralization is considered adaptive for an individual, and often results in "handedness," "footedness," or a side preference, manifest in behavior and morphology. we tested for lateralization in several behaviors in a wild population of magellanic penguins spheniscus magellanicus breeding at punta tombo, argentina. we found no preferred foot in the population (each penguin observed once) in stepping up ...201931149402
venous and arterial acid-base analysis of magellanic penguins (spheniscus magellanicus), awake and anesthetized by isoflurane.this study aimed to compare the venous acid-base status of healthy awake versus anesthetized magellanic penguins (spheniscus magellanicus). ten nonanesthetized penguins were manually restrained, and a venous blood sample was collected. six of these penguins were anesthetized by 2% isoflurane and, after an anesthetic stabilization period, both venous and arterial blood samples were simultaneously withdrawn. using an i-stat analyzer, partial pressure of carbon dioxide (pco2), partial pressure of o ...201931120688
evaluation of antibodies against toxoplasma gondii and leptospira spp. in magellanic penguins (spheniscus magellanicus) on magdalena island, chile.toxoplasmosis has been reported in many avian species, but little information is available from wild penguin populations. leptospira can infects domestic and wild animals. spheniscus magellanicus belong to the order sphenisciformes, family spheniscidae, and are colonial birds. these seabirds live in temperate waters along the atlantic shores of south america, and their total population has been estimated to be 1,300,000 breeding pairs. magdalena island (chile) hosts an important breeding colony ...201931027597
nasal mites (mesostigmata: rhinonyssidae) in african penguins (spheniscus demersus).rhinonyssids are obligate haematophagous mites that parasitize the nasal cavity of vertebrates, and occur in a wide range of birds worldwide. two species of nasal mites are known to occur in penguins: rhinonyssus sphenisci, which has been recorded from humboldt and magellanic penguins (spheniscus humboldti and s. magellanicus, respectively), and rhinonyssus schelli, which has been recorded in adélie and gentoo penguins (pygoscelis adeliae and p. papua, respectively). we examined the nasal cavity ...201929921335
sarcocystis falcatula-like derived from opossum in northeastern brazil: in vitro propagation in avian cells, molecular characterization and bioassay in birds.most reported isolates of sarcocystis spp. derived from brazilian opossums (didelphis sp.) have genetic characteristics distinct from the known species of sarcocystis, but behave similarly as sarcocystis falcatula, as they are infective to budgerigars. in previous studies, these brazilian isolates, classified as sarcocystis falcatula-like, were originated from south and southeast regions of brazil. in the current work, we aimed to culture and to perform multilocus sequence analysis of sarcocysti ...201931516824
late onset of cerebellar cortical degeneration in a magellanic penguin (spheniscus magellanicus).an 8-year-old female magellanic penguin (spheniscus magellanicus) started to show epilepsy-like seizures. subsequent magnetic resonance imaging (mri) examinations did not reveal any responsible lesions. the neurological symptoms worsened at the age of 10. this penguin became recumbent and died 6 months later after the apparition of the recumbency. at necropsy, only multiple yellowish necrotic lesions in the air sacs and lungs were found. histopathological evaluation of the brain showed a marked ...201930956256
species of contracaecum parasitizing the magellanic penguin spheniscus magellanicus (spheniscidae) from the argentinean coast.anisakid nematodes have a worldwide distribution and are associated with fishes, birds, and marine mammals from freshwater, brackish, and marine systems. the aims of this work are to report for the first time contracaecum mirounga parasitizing the magellanic penguin spheniscus magellanicus, to report another contracaecum species in the same host species, and to discuss the validity of contracaeceum spheniscus. several dead chicks, juveniles, and adults of s. magellanicus were collected along the ...201930900944
comparative morphometric evaluation of hepatic hemosiderosis in wild magellanic penguins (spheniscus magellanicus) infected with different plasmodium spp. subgenera.avian malaria is one of the most important diseases of captive penguins. we employed morphometric techniques to evaluate hepatic hemosiderosis in rehabilitating wild magellanic penguins (spheniscus magellanicus) that were negative (n = 9) or naturally infected by different subgenera of plasmodium spp. (n = 24), according with: plasmodium subgenera (haemamoeba, huffia, other lineages, and unidentified lineages), severity of plasmodium histopathological lesions, and concurrent diseases, age class ...201930810664
correction: occurrence of tissue cyst forming coccidia in magellanic penguins (spheniscus magellanicus) rescued on the coast of brazil.[this corrects the article doi: 10.1371/journal.pone.0209007.].201930742697
multi-species okadaic acid contamination and human poisoning during a massive bloom of dinophysis acuminata complex in southern brazil.on june 2016, a major bloom of dinophysis acuminata complex was noticed over the coast of paraná state (pr), southern brazil, an area unprotected by any official monitoring program. here we report the results of an extensive sampling effort that ultimately led pr authorities to issue the first state shellfish-harvesting ban due to multi-species okadaic acid (oa) contamination. during its peak, the bloom covered an area of 201 km2 (∼2.0-3.5 × 54.0 km), attaining unprecedentedly high cell densitie ...201931672229
heterophyid trematodes (digenea) from penguins: a new species of ascocotyle looss, 1899, first description of metacercaria of ascocotyle (a.) patagoniensis hernández-orts et al. (2012), and first molecular data.two species of heterophyid trematodes were found in the magellanic penguin, spheniscus magellanicus (forster), from patagonia, argentina. ascocotyle (ascocotyle) patagoniensis hernández-orts et al. (2012) is re-described based on new, properly fixed specimens (original material from south american sea lion, otaria flavescens shaw, was from frozen hosts). metacercariae of this species are reported and described for the first time from the heart of the silversides, odontesthes argentinensis (valen ...201930723670
application of different pharmacokinetic models to describe and predict pharmacokinetics of voriconazole in magellanic penguins following oral administration.aspergillosis is a condition causing serious morbidity and mortality in captive penguins and other bird species. it can be treated with antifungal drugs, such as voriconazole. however, the pharmacokinetics of voriconazole are variable between different animal and bird species. therefore, the pharmacokinetics of voriconazole were investigated in this study in magellanic penguins. pharmacokinetic models were constructed and applied to predict the pharmacokinetics of voriconazole during long-term t ...201930175535
novel ehrlichia sp. detected in magellanic penguins (sphenicus magellanicus) and in the seabird tick ixodes uriae from magdalena island, southern chile.ehrlichia spp. are obligatory intracellular microorganisms that infect hematopoietic, endothelial or blood cells of mammals. ticks are the only vectors of these agents in nature. to date, the role of birds and their associated ticks as reservoirs of ehrlichiae remains almost unexplored. in this study, we performed a molecular screening for bacteria of anaplasmataceae family in samples of spleen (n = 72) and lung (n = 17), recovered from 72 carcasses of magellanic penguins (spheniscus magellanicu ...201931255535
female-biased stranding in magellanic penguins.magellanic penguins (spheniscus magellanicus) have been reported to become stranded along the coasts of northern argentina, uruguay and southern brazil during the austral winter [1-3]. this location is more than a thousand kilometers distant from their northernmost breeding colony in northern patagonia. curiously, females typically outnumber males at stranding sites (approximately three females per male) [2]. to date, no conspicuous sex differences have been reported in their migratory movements ...201930620906
epidemiology, hematology, and unusual morphological characteristics of plasmodium during an avian malaria outbreak in penguins in brazil.avian malaria is a mosquito-borne disease caused by plasmodium spp. protozoa, and penguins are considered particularly susceptible to this disease, developing rapid outbreaks with potentially high mortality. we report on an outbreak of avian malaria in magellanic penguins (spheniscus magellanicus) at a rehabilitation center in espírito santo, southeast brazil. in august and september 2015, a total of 89 magellanic penguins (87 juveniles and 2 adults) received care at institute of research and re ...201931720833
sex-biased survival contributes to population decline in a long-lived seabird, the magellanic penguin.we developed a hidden markov mark-recapture model (r package marked) to examine sex-specific demography in magellanic penguins (spheniscus magellanicus). our model was based on 33 yr of resightings at punta tombo, argentina, where we banded ~44,000 chicks from 1983 to 2010. because we sexed only 57% of individuals over their lifetime, we treated sex as an uncertain state in our model. our goals were to provide insight into the population dynamics of this declining colony, to inform conservation ...201930601594
applicability of the platelia eia® aspergillus test for the diagnosis of aspergilosis in penguins.even today, an effective diagnostic test for aspergillosis in penguins is unknown, being the gold standard post-mortem examinations. the fungal antigen galactomannan (gm) has been used as a biomarker of disease in humans and is detected by the platelia aspergillus eia (biorad)®, a commercial kit based on the sandwich elisa technique. it is standardized for use in neutropenic patients, however studies have demonstrated its usefulness also possible for birds. the aim of our study was to evaluate t ...201930133554
pathological and molecular characterization of avian malaria in captive magellanic penguins (spheniscus magellanicus) in south america.avian malaria is a mosquito-borne disease that affects multiple avian species and is caused by protozoans of the genus plasmodium. an avian malaria infection caused by plasmodium sp. in magellanic penguins (spheniscus magellanicus) with high mortality is described in a zoo in southern brazil. clinically, three birds presented signs of inappetence, anorexia, pale mucosa, dyspnea, and opisthotonus, with death in a clinical course of 5-8 h. at the necropsy, all birds exhibited pale mucosa, marked s ...201930456492
ecotourism effects on health and immunity of magellanic penguins at two reproductive colonies with disparate touristic regimes and population trends.negative effects of ecotourism on wildlife are rising worldwide. conservation physiology can play a major role in protecting wildlife by providing early alerts on changes in the status of individuals exposed to tourist activities. we measured an integrated set of immune and health-state indices to evaluate the effects of ecotourism on magellanic penguins (spheniscus magellanicus). we studied two reproductive colonies that differed in the intensity of tourism and population trends: punta tombo (h ...201830464841
food provisioning in magellanic penguins as inferred from stable isotope ratios.food provisioning is considered one of the main traits affecting offspring fitness. differences in food provisioning between sexes, particularly in dimorphic species, could affect the amount and type of food provided, due to differences in the amount of food carried to the nest as a result of differential resources exploitation. quantitative evidence for sexual differences in food provisioning by parents in penguins is scarce. the magellanic penguin is moderately sexually dimorphic and breeds al ...201829361198
draft genome sequence of an extensively drug-resistant pseudomonas aeruginosa isolate belonging to st644 isolated from a footpad infection in a magellanic penguin (spheniscus magellanicus).the incidence of multidrug-resistant bacteria in wildlife animals has been investigated to improve our knowledge of the spread of clinically relevant antimicrobial resistance genes. the aim of this study was to report the first draft genome sequence of an extensively drug-resistant (xdr) pseudomonas aeruginosa st644 isolate recovered from a magellanic penguin with a footpad infection (bumblefoot) undergoing rehabilitation process.201829277728
occurrence of tissue cyst forming coccidia in magellanic penguins (spheniscus magellanicus) rescued on the coast of brazil.the main motivation for this study was to determine the occurrence of toxoplasma gondii, a cosmopolitan widespread zoonotic parasite distribution that can infect a wide variety of mammals and birds, in magellanic penguins (spheniscus magellanicus) in brazil. in recent decades there has been a significant increase in the number of penguins originating from argentinian and chilean patagonia, where these birds are born, that arrive on the brazilian coast, where many of them are stranded and rescued ...201830562391
variation in mercury concentration in juvenile magellanic penguins during their migration path along the southwest atlantic ocean.the vulnerability of seabirds related to their migratory dynamics is frequently linked to environmental problems along the migration path. in this context, magellanic penguins (sphenicus magellanicus) seem to be vulnerable to an extensive range of environmental disturbances during their northward migration along the atlantic waters of south america, which include by catch, marine debris ingestion, overfishing and environmental contamination. in this study, we investigate mercury accumulation in ...201829587210
luck in food finding affects individual performance and population trajectories.energy harvesting by animals is important because it provides the power needed for all metabolic processes. beyond this, efficient food finding enhances individual fitness [1] and population viability [2], although rates of energy accumulation are affected by the environment and food distribution. typically, differences between individuals in the rate of food acquisition are attributed to varying competencies [3], even though food-encounter rates are known to be probabilistic [4]. we used animal ...201830449669
schistosomes and microfilarial parasites in magellanic penguins.the magellanic penguin (spheniscus magellanicus) is native to argentina, chile and the falkland/malvinas islands and is a regular winter migrant in uruguayan and brazilian coastal waters. the species is known to be susceptible to a variety of gastrointestinal nematodes, cestodes, trematodes and acanthocephalans, as well as renal trematodes and pulmonary nematodes. schistosomes (platyhelminthes, trematoda, schistosomatidae) and microfilariae (nematoda, secernentea, onchocercidae) were histologica ...201829424659
long necks enhance and constrain foraging capacity in aquatic vertebrates.highly specialized diving birds display substantial dichotomy in neck length with, for example, cormorants and anhingas having extreme necks, while penguins and auks have minimized necks. we attached acceleration loggers to imperial cormorants phalacrocorax atriceps and magellanic penguins spheniscus magellanicus, both foraging in waters over the patagonian shelf, to examine the difference in movement between their respective heads and bodies in an attempt to explain this dichotomy. the penguins ...201729142117
from mammals back to birds: host-switch of the acanthocephalan corynosoma australe from pinnipeds to the magellanic penguin spheniscus magellanicus.trophically-transmitted parasites are regularly exposed to potential new hosts through food web interactions. successful colonization, or switching, to novel hosts, occur readily when 'donor' and 'target' hosts are phylogenetically related, whereas switching between distantly related hosts is rare and may result from stochastic factors (i.e. rare favourable mutations). this study investigates a host-switching event between a marine acanthocephalan specific to pinnipeds that is apparently able to ...201728981550
marine debris boost in juvenile magellanic penguins stranded in south-eastern brazil in less than a decade: insights into feeding habits and habitat use.the magellanic penguin (spheniscus magellanicus) is a marine sentinel for the southern atlantic ocean that is a proxy of environmental quality. the presence of marine debris (macro-debris) in the stomach contents of emaciated juvenile penguins stranded from 21°s to 23°s was compared at different times (2000 and 2008), and the debris ingestion pathway was determined. the frequency of marine debris in the stomachs doubled in less than a decade, and flexible plastics remained the main ingested item ...201728958439
escherichia coli carrying incx4 plasmid-mediated mcr-1 and blactx-m genes in infected migratory magellanic penguins (spheniscus magellanicus). 201728031274
enterococcus species diversity in fecal samples of wild marine species as determined by real-time pcr.analyses using culture-independent molecular techniques have improved our understanding of microbial composition. the aim of this work was to identify and quantify enterococci in fecal samples of wild marine species using real-time quantitative pcr. seven enterococcus species were examined in fecal dna of south american fur seals (arctocephalus australis), subantarctic fur seals (arctocephalus tropicalis), green turtles (chelonia mydas), magellanic penguins (spheniscus magellanicus), snowy-crown ...201727991828
do blood parasites infect magellanic penguins (spheniscus magellanicus) in the wild? prospective investigation and climatogeographic considerations.magellanic penguins (spheniscus magellanicus) are native to argentina, chile and the falkland islands. magellanic penguins are highly susceptible to blood parasites such as the mosquito-borne plasmodium spp., which have been documented causing high morbidity and mortality in zoos and rehabilitation centres. however, to date no blood parasites have been detected in wild magellanic penguins, and it is not clear whether this is reflective of their true absence or is instead related to an insufficie ...201728073384
magellanic penguin telomeres do not shorten with age with increased reproductive effort, investment, and basal corticosterone.all species should invest in systems that enhance longevity; however, a fundamental adult life-history trade-off exists between the metabolic resources allocated to maintenance and those allocated to reproduction. long-lived species will invest more in reproduction than in somatic maintenance as they age. we investigated this trade-off by analyzing correlations among telomere length, reproductive effort and output, and basal corticosterone in magellanic penguins (spheniscus magellanicus). telome ...201728811878
genetically diverse herpesviruses in south american atlantic coast seabirds.different herpesviruses have been associated with respiratory and enteric disease and mortality among seabirds and waterfowl. in 2011, a respiratory disease outbreak affected 58.3% (98/168) of the magellanic penguins undergoing rehabilitation due to an oil spill off the southern brazilian coast. etiology was attributed to a novel herpesvirus identified by histopathology, immunohistochemistry, electron microscopy and molecular studies with partial dna sequencing. since migration, rehabilitation a ...201728575104
corrigendum to "persistent organic pollutants in juvenile magellanic penguins (spheniscus magellanicus) in south america" [chemosphere 149 (2016) 391-399]. 201728576431
acoustic correlates of body size and individual identity in banded penguins.animal vocalisations play a role in individual recognition and mate choice. in nesting penguins, acoustic variation in vocalisations originates from distinctiveness in the morphology of the vocal apparatus. using the source-filter theory approach, we investigated vocal individuality cues and correlates of body size and mass in the ecstatic display songs the humboldt and magellanic penguins. we demonstrate that both fundamental frequency (f0) and formants (f1-f4) are essential vocal features to d ...201728199318
a new species of diomedenema (nematoda, rhabditida, spiruromorpha) from spheniscus magellanicus (aves, sphenisciformes) found on the southern coast of brazil.a new species of the genus diomedenema, a spiruromorph nematode, collected from the lung of spheniscus magellanicus (sphenisciformes) found on the southern coast of the state of rio grande do sul, brazil, is described. the new species is differentiated from the only previously described species of the genus, d. diomedeae johston & mawson, 1952, by males possessing a set of caudal papillae with three pairs of precloacal, two pairs of adcloacal and one pair of postcloacal papillae; precloacal papi ...201728780915
telomeres shorten and then lengthen before fledging in magellanic penguins (spheniscus magellanicus).for all species, finite metabolic resources must be allocated toward three competing systems: maintenance, reproduction, and growth. telomeres, the nucleoprotein tips of chromosomes, which shorten with age in most species, are correlated with increased survival. chick growth is energetically costly and is associated with telomere shortening in most species. to assess the change in telomeres in penguin chicks, we quantified change in telomere length of wild known-age magellanic penguin (spheniscu ...201728186493
chicks produced in the magellanic penguin (spheniscus magellanicus) after cloacal insemination of frozen-thawed semen.the in vitro and in vivo functionality of cryopreserved spermatozoa was examined over two breeding seasons in a zoological colony of magellanic penguins (spheniscus magellanicus). frozen-thawed semen was inseminated into five anesthetized females, over a total of eight egg production cycles, with a different male used for each artificial insemination (ai) within each season. females were maintained within the colony in cordoned nest sites to prevent copulation with their paired male, and were in ...201627272488
vocal individuality and species divergence in the contact calls of banded penguins.penguins produce contact calls to maintain social relationships and group cohesion. such vocalisations have recently been demonstrated to encode individual identity information in the african penguin. using a source-filter theory approach, we investigated whether acoustic cues of individuality can also be found in other spheniscus penguins and the acoustic features of contact calls have diverged within this genus. we recorded vocalisations from two ex-situ colonies of humboldt penguin and magell ...201627102762
male reproductive physiology and the development of artificial insemination in the magellanic penguin (spheniscus magellanicus) using chilled-stored semen.research was performed to increase our understanding of male magellanic penguin (spheniscus magellanicus) reproductive biology and to develop artificial insemination (ai) technology to assist with maintaining the species' genetic diversity. seminal traits were characterized from seven males with noncontaminated ejaculates (n = 123) displaying high in vitro motion parameters, membrane integrity, and morphology. seven females were maintained in nest sites that permitted visual, auditory, and tacti ...201627010281
reproductive physiology of the female magellanic penguin (spheniscus magellanicus): insights from the study of a zoological colony.eight captive female magellanic penguins (spheniscus magellanicus) were monitored over a 10week period, commencing at 5weeks prior to egg lay (el), to increase our understanding of the species' reproductive biology. females in cordoned nest sites underwent cloacal artificial insemination (ai) every 4-7days with different semen donors for each insemination. the el interval was 97.9±3.6h (range: 84-108h) and paternity analyses revealed that conceptive inseminations occurred from 11.5 to 4.5days be ...201626393312
blood-specific isotopic discrimination factors in the magellanic penguin (spheniscus magellanicus).the use of stable isotopes for ecological studies has increased exponentially in recent years. isotopic trophic studies are based on the assumption that animals are what they eat plus a discrimination factor. the discrimination factor is affected by many variables and can be determined empirically. the magellanic penguin is a highly abundant marine bird that plays a key role in the southern oceans. this study provides the first estimation of the magellanic penguin blood discrimination factor for ...201627476661
first report of kidney lesions due to renicola sp. (digenea: trematoda) in free-living magellanic penguins ( spheniscus magellanicus forster, 1781) found on the coast of brazil.this paper presents the first report of parasites from the genus renicola sp. in the kidneys of magellanic penguins. the histological analysis revealed inflammatory infiltrate (eonsinophils, lymphocytes, and plasmocytes), together with fibroplasia and compression of the adjacent ducts.201627552082
avian malaria ( plasmodium spp.) in captive magellanic penguins ( spheniscus magellanicus ) from northern argentina, 2010.we report two cases of lethal avian malaria in magellanic penguins (spheniscus magellanicus) captive at san clemente del tuyú, argentina, approximately 560 km north of argentinean breeding colonies of magellanic penguins. blood smears revealed both penguins were concurrently infected by plasmodium (haemamoeba) tejerai, plasmodium (huffia) sp., and plasmodium (novyella) sp.201627285418
persistent organic pollutants in juvenile magellanic penguins (spheniscus magellanicus) in south america.magellanic penguins, spheniscus magellanicus, are the most abundant penguins living in temperate regions of south america and are good indicators of environmental pollution in the region. persistent organic pollutants (pops) were detected in the liver of magellanic penguins found debilitated or dead on the beaches of brazil (states of rio de janeiro, sao paulo, santa catarina and rio grande do sul) between 2008 and 2012 as well as in uruguay and chile in 2011. polychlorinated biphenyls (pcbs) we ...201626881336
lesions associated with drowning in bycaught penguins.fisheries bycatch, the incidental mortality that occurs as a result of entanglement in fishing gear, is an important conservation threat to penguins and other seabirds. identification of entanglement and drowning in beach-cast carcasses of seabirds remains a challenge, as it is still unclear what lesions are to be expected in a bycaught seabird. we necropsied 2 magellanic penguins spheniscus magellanicus that were entangled and drowned in gillnets. marked distension of the lungs with foamy red f ...201627786162
survey of toxoplasma gondii antibodies in magellanic penguins (spheniscus magellanicus forster, 1781).magellanic penguins (spheniscus magellanicus) breed on the atlantic and pacific coasts of the southernmost parts of south america and migrate northward as far as peru and brazil. serum samples (n = 100) from magellanic penguins from three zoos and two rehabilitation centers (rcs) in brazil were assayed for the presence of antibodies to toxoplasma gondii by means of the modified agglutination test (mat, cut-off ≥ 20). the penguins were categorized as young (≤4 yr old) or adults (≥4 yr old) and se ...201627010304
complete genome sequence of enterococcus faecalis strain p8-1 isolated from wild magellanic penguin (spheniscus magellanicus) feces on the south coast of brazil.enterococcus faecalis strains have a ubiquitous nature that allows them to survive in different niches. studies involving enterococci isolated from marine animals are scarce. therefore, in this study, we report the complete genome sequence of e. faecalis strain p8-1 isolated from feces of a magellanic penguin on the south coast of brazil.201626769928
contrasting patterns of selection between mhc i and ii across populations of humboldt and magellanic penguins.the evolutionary and adaptive potential of populations or species facing an emerging infectious disease depends on their genetic diversity in genes, such as the major histocompatibility complex (mhc). in birds, mhc class i deals predominantly with intracellular infections (e.g., viruses) and mhc class ii with extracellular infections (e.g., bacteria). therefore, patterns of mhc i and ii diversity may differ between species and across populations of species depending on the relative effect of loc ...201628725416
voriconazole toxicity in multiple penguin species.aspergillosis is a common respiratory fungal disease in penguins managed under human care. triazole antifungal drugs, including itraconazole, are most commonly used for treatment; however, itraconazole treatment failures from drug resistance are becoming more common, requiring newer treatment options. voriconazole, a newer triazole, is being used more often. until recently, no voriconazole pharmacokinetic studies had been performed in penguins, leading to empiric dosing based on other avian stud ...201526667545
incidence density, proportionate mortality, and risk factors of aspergillosis in magellanic penguins in a rehabilitation center from brazil.aspergillosis, an opportunistic mycosis caused by the aspergillus genus, affects mainly the respiratory system and is considered one of the most significant causes of mortality in captive penguins. this study aimed to examine a 6-yr period of cases of aspergillosis in penguins at the centro de recuperação de animais marinhos (cram-furg), rio grande, brazil. a retrospective cohort study was conducted using the institution's records of penguins received from january 2004 to december 2009. animals ...201526667521
detection of salmonella enterica in magellanic penguins (spheniscus magellanicus) of chilean patagonia: evidences of inter-species transmission.patagonia in southern south america is among the few world regions where direct human impact is still limited but progressively increasing, mainly represented by tourism, farming, fishing and mining activities. the sanitary condition of patagonian wildlife is unknown, in spite of being critical for the assessment of anthropogenic effects there. the aim of this study was the characterization of salmonella enterica strains isolated from wild colonies of magellanic penguins (spheniscus magellanicus ...201525148565
variations in the morphology of rhizomucor pusillus in granulomatous lesions of a magellanic penguin (spheniscus magellanicus).this report presents a new case of mucormycosis encountered in penguin characterized by morphological variation of hyphae and presence of sporangia with numerous sporangiospores. a 4.5-year-old magellanic penguin (spheniscus magellanicus) died after exhibiting anorexia, poor nutritional condition and dyspnea. multiple nodular lesions were observed in the thoracic and abdominal regions. histopathologically, hyphae of various sizes were seen in the lungs, air sac and nodular lesions. myriad sporan ...201525892614
creation and validation of a novel body condition scoring method for the magellanic penguin (spheniscus magellanicus) in the zoo setting.this research aims to validate a novel, visual body scoring system created for the magellanic penguin (spheniscus magellanicus) suitable for the zoo practitioner. magellanics go through marked seasonal fluctuations in body mass gains and losses. a standardized multi-variable visual body condition guide may provide a more sensitive and objective assessment tool compared to the previously used single variable method. accurate body condition scores paired with seasonal weight variation measurements ...201526768691
trace-elements, methylmercury and metallothionein levels in magellanic penguin (spheniscus magellanicus) found stranded on the southern brazilian coast.magellanic penguins have been reported as good biomonitors for several types of pollutants, including trace-elements. in this context, selenium (se), total mercury, methylmercury, inorganic mercury (hg(inorg)), cadmium (cd) and lead (pb), as well as metallothionein (mt) levels, were evaluated in the feathers, liver and kidney of juvenile magellanic penguins found stranded along the coast of southern brazil. the highest concentrations of all trace-elements and methylmercury were found in internal ...201525960272
isolation and characterization of igm and igy antibodies from plasma of magellanic penguins (spheniscus magellanicus).infectious diseases such as aspergillosis, avian malaria, and viral infections are significant threats to the conservation of penguins, leading to morbidity and mortality of these birds both in captivity and in the wild. the immune response to such infectious diseases is dependent on different mechanisms mediated by cells and soluble components such as antibodies. antibodies or immunoglobulins are glycoproteins that have many structural and functional features that mediate distinct effector immu ...201526292539
a comprehensive assessment of mercury exposure in penguin populations throughout the southern hemisphere: using trophic calculations to identify sources of population-level variation.the wide geographic distribution of penguins (order sphenisciformes) throughout the southern hemisphere provided a unique opportunity to use a single taxonomic group as biomonitors of mercury among geographically distinct marine ecosystems. mercury concentrations were compared among ten species of penguins representing 26 geographically distinct breeding populations. mercury concentrations were relatively low (⩽2.00ppm) in feathers from 18/26 populations considered. population-level differences ...201526072048
epidemiology and pathology of avian malaria in penguins undergoing rehabilitation in brazil.seabird rehabilitation is a valuable strategy to mitigate the impacts of oil pollution and other anthropogenic factors, and can significantly contribute to the conservation of penguins. however, infectious diseases such as avian malaria (plasmodium spp.) can hamper the success of rehabilitation efforts. we combined morphological and molecular diagnostic methods to investigate the epidemiology and pathology of plasmodium in magellanic penguins (spheniscus magellanicus) at rehabilitation centers a ...201525888987
comparative study between photodynamic and antibiotic therapies for treatment of footpad dermatitis (bumblefoot) in magellanic penguins (spheniscus magellanicus).bumblefoot, referring to bed-sore-like foot lesions, is one of the most important clinical complications in captive birds and has a multifactorial etiology. photodynamic therapy has been proposed as an alternative treatment for localized infections in response to the escalating problem of antibiotic resistance. the aim of this study was to compare outcomes in a group of captive spheniscus magellanicus with bumblefoot lesions treated with photodynamic therapy (pdt) or antibiotics (atb).201525573284
population regulation in magellanic penguins: what determines changes in colony size?seabirds are often studied at individual colonies, but the confounding effects of emigration and mortality processes in open populations may lead to inappropriate conclusions on the mechanisms underlying population changes. magellanic penguin (spheniscus magellanicus) colonies of variable population sizes are distributed along the argentine coastline. in recent decades, several population and distributional changes have occurred, with some colonies declining and others newly established or incre ...201525786254
molecular epidemiology of avian malaria in wild breeding colonies of humboldt and magellanic penguins in south america.avian malaria is a disease caused by species of the genera haemoproteus, leucocytozoon, and plasmodium. it affects hundreds of bird species, causing varied clinical signs depending on the susceptibility of the host species. although high mortality has been reported in captive penguins, limited epidemiological studies have been conducted in wild colonies, and isolated records of avian malaria have been reported mostly from individuals referred to rehabilitation centers. for this epidemiological s ...201525492695
outbreak of avian malaria associated to multiple species of plasmodium in magellanic penguins undergoing rehabilitation in southern brazil.avian malaria is a mosquito-borne disease caused by plasmodium spp. avian plasmodia are recognized conservation-threatening pathogens due to their potential to cause severe epizootics when introduced to bird populations with which they did not co-evolve. penguins are considered particularly susceptible, as outbreaks in captive populations will often lead to high morbidity and rapid mortality. we used a multidisciplinary approach to investigate an outbreak of avian malaria in 28 magellanic pengui ...201424736326
photodynamic therapy for pododermatitis in penguins.pododermatitis is currently one of most frequent and important clinical complications in seabirds kept in captivity or in rehabilitation centers. in this study, five magellanic penguins with previous pododermatitis lesions on their footpad were treated with photodynamic therapy (pdt). all pdt treated lesions successfully regressed and no recurrence was observed during the 6-month follow-up period. pdt seems to be an inexpensive and effective alternative treatment for pododermatitis in magellanic ...201424888264
climate change increases reproductive failure in magellanic penguins.climate change is causing more frequent and intense storms, and climate models predict this trend will continue, potentially affecting wildlife populations. since 1960 the number of days with >20 mm of rain increased near punta tombo, argentina. between 1983 and 2010 we followed 3496 known-age magellanic penguin (spheniscus magellanicus) chicks at punta tombo to determine how weather impacted their survival. in two years, rain was the most common cause of death killing 50% and 43% of chicks. in ...201424489663
high-throughput gender identification of penguin species using melting curve analysis.most species of penguins are sexual monomorphic and therefore it is difficult to visually identify their genders for monitoring population stability in terms of sex ratio analysis. in this study, we evaluated the suitability using melting curve analysis (mca) for high-throughput gender identification of penguins. preliminary test indicated that the griffiths's p2/p8 primers were not suitable for mca analysis. based on sequence alignment of chromo-helicase-dna binding protein (chd)-w and chd-z ge ...201424555797
longer and less overlapping food webs in anthropogenically disturbed marine ecosystems: confirmations from the past.the human exploitation of marine resources is characterised by the preferential removal of the largest species. although this is expected to modify the structure of food webs, we have a relatively poor understanding of the potential consequences of such alteration. here, we take advantage of a collection of ancient consumer tissues, using stable isotope analysis and siber to assess changes in the structure of coastal marine food webs in the south-western atlantic through the second half of the h ...201425076042
molecular and morphological characterization of contracaecum pelagicum (nematoda) parasitizing spheniscus magellanicus (chordata) from brazilian waters.three new sequences of mitochondrial cytochrome c-oxidase subunit 2 (mtdna cox-2) from c. pelagicum parasite of spheniscus magellanicus, the magelanicus penguin, were determined from brazilian waters. the sequences presented 99 and 98% of similarity with c. pelagicum sequences from argentina, deposited on genbank for the same genetic region and with a strong statistical support inferred from the phylogenetic tree. the morphological and ultrastructural studies that were carried out confirmed the ...201424728364
ecological aspects of helminth fauna of magellanic penguins, spheniscus magellanicus (aves: spheniscidae), from the northern coast of the state of são paulo, brazil.the aim of the present study was to evaluate the helminth fauna found in the magellanic penguin, spheniscus magellanicus, relating parasite population and community ecological parameters to life aspects of the host species. the study involved 237 specimens of s. magellanicus taken from the northern shore of the state of são paulo (23° 46' s, 45° 57' w) and southern shore of the state of rio de janeiro (23° 02' s, 44° 13' w), brazil. the following helminth fauna were found: the nematode contracae ...201323644789
sex identification of four penguin species using locus-specific pcr.traditional methods for sex identification are not applicable to sexually monomorphic species, leading to difficulties in the management of their breeding programs. to identify sex in sexually monomorphic birds, molecular methods have been established. two established primer pairs (2550f/2718r and p8/p2) amplify the chd1 gene region from both the z and w chromosomes. here, we evaluated the use of these primers for sex identification in four sexually monomorphic penguin species: king penguins (ap ...201322383375
new records and descriptions of digeneans from the magellanic penguin spheniscus magellanicus (forster) (aves: sphenisciformes) on the coast of brazil.five species of digeneans parasitic in the magellanic penguin spheniscus magellanicus (forster) from off the brazilian coast of the western atlantic are reported for the first time from this host and described. these are mesostephanus odhneri (travassos, 1924) lutz, 1935, posthodiplostomum macrocotyle dubois, 1937, stephanoprora uruguayensis holcman-spector & olagüe, 1989, ascocotyle (phagicola) longa ransom, 1920 and ascocotyle (phagicola) sp. one other digenean, cardiocephaloides physalis (lut ...201323595494
molecular identification and larval morphological description of contracaecum pelagicum (nematoda: anisakidae) from the anchovy engraulis anchoita (engraulidae) and fish-eating birds from the argentine north patagonian sea.anisakids use invertebrates as paratenic and/or intermediate hosts as a basic feature of larval transmission. the third-stage larva usually develops in invertebrates which are prey items of finfish paratenic hosts. contracaecum larvae molt twice inside the egg and hatch as free third-stage larvae ensheathed in the second-stage larval cuticle. copepods act as paratenic or obligatory hosts, usually ingesting these free l3 larvae, and fish act as intermediate/paratenic or metaparatenic hosts preyin ...201323500719
behavioral responses of magellanic penguins (spheniscus magellanicus) (foster) to saltwater versus freshwater.the most common penguin species found along the coast of brazil is the magellanic penguin (spheniscus magellanicus). these penguins spend most of their time foraging for food in the oceans. this information is vital to the maintenance of this species in captivity. the goal of this study was to evaluate the behavioral response of a group of magellanic penguins (s. magellanicus) in two different conditions of water--fresh and salt. the work was divided into two phases. first, animals were kept in ...201323877966
two different avipoxviruses associated with pox disease in magellanic penguins (spheniscus magellanicus) along the brazilian coast.a novel avipoxvirus caused diphtheritic lesions in the oesophagus of five and in the bronchioli of four magellanic penguins (spheniscus magellanicus) and also cutaneous lesions in eight magellanic penguins housed in outdoor enclosures in a rehabilitation centre at florianópolis, santa catarina state, brazil. at the same time, another avipoxvirus strain caused cutaneous lesions in three magellanic penguins at a geographically distinct rehabilitation centre localized at vila velha, espírito santo ...201324164638
how much is too much? assessment of prey consumption by magellanic penguins in patagonian colonies.penguins are major consumers in the southern oceans although quantification of this has been problematic. one suggestion proposes the use of points of inflection in diving profiles ('wiggles') for this, a method that has been validated for the estimation of prey consumption by magellanic penguins (spheniscus magellanicus) by simeone and wilson (2003). following them, we used wiggles from 31 depth logger-equipped magellanic penguins foraging from four patagonian colonies; punta norte (pn), bahía ...201223251554
mhc diversity and mate choice in the magellanic penguin, spheniscus magellanicus.we estimated levels of diversity at the major histocompatibility complex (mhc) class ii drß1 gene in 50 breeding pairs of the magellanic penguin and compared those to estimates from humboldt and galapagos penguins. we tested for positive selection and 2 conditions required for the evolution of mhc-based disassortative mating: 1) greater mhc diversity between breeding pairs compared to random mating, and 2) associations between mhc genotype and fitness. cloning and sequencing of the drß1 gene sho ...201222952272
parasitological and new molecular-phylogenetic characterization of the malaria parasite plasmodium tejerai in south american penguins.this study is the first report on mortality of spheniscus magellanicus, penguin of south america, caused by plasmodium tejerai, which was identified using morphological and molecular analyses. blood stages (trophozoites, meronts and gametocytes) were reported and illustrated. the necropsy revealed marked splenomegaly and pulmonary edema, as well as moderate hepatomegaly and hydropericardium. the histopathology revealed the presence of tissue meronts in the macrophages and endothelial cells of mu ...201223269202
incorrect likelihood methods were used to infer scaling laws of marine predator search behaviour.ecologists are collecting extensive data concerning movements of animals in marine ecosystems. such data need to be analysed with valid statistical methods to yield meaningful conclusions.201223071508
an outbreak of chlamydophila psittaci in an outdoor colony of magellanic penguins (spheniscus magellanicus).an outbreak of chlamydophila psittaci occurred in an outdoor colony of 63 magellanic penguins (spheniscus magellanicus) at the san francisco zoo. affected penguins presented with inappetence, lethargy, and light green urates. hematologic and serum biochemical findings were consistent with chronic inflammation. penguins did not respond to initial supportive and antimicrobial therapy, and 3 died. necropsy results of the 3 birds revealed hepatomegaly and splenomegaly, and histologic lesions include ...201223409434
persistent organic pollutants in juvenile magellan penguins (spheniscus magellanicus) found on the northern shore of the state of são paulo and southern shore of the state of rio de janeiro, brazil.in the present study, persistent organic pollutants (pops) were determined in 25 livers from magellanic penguins, spheniscus magellanicus, found on the state of são paulo and rio de janeiro (brazil). the following concentrations of pops (wet weight) were found: ∑ pcbs: 18.9-775.8 ng g(-1); ∑ ddts: 2.3-275 ng g(-1); and ∑ hchs: 1.0-11.8 ng g(-1). among the pcbs, there was a predominance of hexachlorobiphenyls (138 and 153) and heptachlorobiphenyls (180 and 187). among the organochlorines, ddt pre ...201222910330
avian pox in magellanic penguins (spheniscus magellanicus).avian pox is an enveloped double-stranded dna virus that is mechanically transmitted via arthropod vectors or mucosal membrane contact with infectious particles or birds. magellanic penguins (spheniscus magellanicus) from two colonies (punta tombo and cabo dos bahías) in argentina showed sporadic, nonepidemic signs of avian pox during five and two of 29 breeding seasons (1982-2010), respectively. in magellanic penguins, avian pox expresses externally as wart-like lesions around the beak, flipper ...201222740548
survival and movements of magellanic penguins rehabilitated from oil fouling along the coast of south america, 2000-2010.oil pollution is a significant conservation concern. we examined data from six institutions along the coast of south america: emergency relief team of the international fund for animal welfare, fundación mundo marino, centro de recuperação de animais marinhos, natura patagonia, associação r3 animal, and mar del plata aquarium and data from resightings in argentina, brazil, chile and falkland/malvinas islands. from 2000 to 2010, 2183 oiled magellanic penguins were rehabilitated as part of the rou ...201222683106
occurrence of magellanic penguins along the northeast brazilian coast during 2008 austral winter.during the austral winter of 2008, thousands of penguins traveled to low latitudes along the south atlantic coast of south america. the atmospheric and oceanic conditions from april to july 2008 may account for the penguins' unusual geographic distribution. during that period, south atlantic coastal waters were cooler; the wind anomalies had northward and onshore components; the ocean's coastal region presented northward currents that favored the penguins to travel toward lower latitudes. this a ...201222649308
mercury levels in feathers of magellanic penguins.feathers are useful to determine mercury (hg) contamination. we evaluated the mercury concentration in feathers of magellanic penguins (spheniscus magellanicus) age 1.5 years to 25 years at punta tombo, argentina before and during their molt. mercury ranged between <1.4 and 367 ng/g dry weight, with three extreme high values (8996 ng/g, 3011 ng/g and 1340 ng/g) all in young adults. the median concentration was lowest for juveniles and significantly higher for adults but with high variation among ...201222465054
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