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1.
Proc Natl Acad Sci U S A ; 120(3): e2209821120, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36623194

RESUMO

Long-term climate changes and extreme climate events differentially impact animal populations, yet whether and why these processes may act synergistically or antagonistically remains unknown. Disentangling these potentially interactive effects is critical for predicting population outcomes as the climate changes. Here, we leverage the "press-pulse" framework, which is used to describe ecological disturbances, to disentangle population responses in migratory Magellanic penguins to long-term changes in climate means and variability (presses) and extreme events (pulses) across multiple climate variables and life history stages. Using an unprecedented 38-y dataset monitoring 53,959 penguins, we show for the first time that the presses and pulses of climate change mediate the rate of population decline by differentially impacting different life stages. Moreover, we find that climate presses and pulses can work both synergistically and antagonistically to affect animal population persistence, necessitating the need to examine both processes in concert. Negative effects of terrestrial heat waves (pulses) on adult survival, for example, were countered by positive effects of long-term changes in oceanographic conditions in migratory grounds (presses) on juvenile and adult survival. Taken together, these effects led to predicted population extirpation under all future climate scenarios. This work underscores the importance of a holistic approach integrating multiple climate variables, life stages, and presses and pulses for predicting the persistence of animals under accelerating climate change.


Assuntos
Spheniscidae , Animais , Dinâmica Populacional , Estágios do Ciclo de Vida , Mudança Climática , Estações do Ano
2.
Mar Pollut Bull ; 188: 114628, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36701975

RESUMO

This paper provides the first evidence of debris pollution, including plastic, in juvenile Magellanic penguins (Spheniscus magellanicus) found stranded on the Atlantic coast of southern Buenos Aires Province, Argentina. Macro-, meso- and microparticles of anthropogenic origin were observed in 100 % of the studied birds, with debris abundance ranging between 33 and 200 items/bird. Microparticles represented 91 % of the total debris and 97 % of them were fibers. Black particles were the most abundant (30 %), followed by transparent (26 %), blue (14 %), yellow (10.3 %), and red (10 %). Infrared and Raman spectroscopy identified 62.7 % of the total particles as plastics, with polypropylene (27.8 %) and polyester (21.6 %) being the most abundant polymers. Semi-synthetic cellulosic fibers, metallic particles, and pigments were also found. The presence of metallic microparticles was suggested for the first time in penguins. Stranded juvenile Magellanic penguins are proposed as promising bioindicators of plastic pollution in the South Atlantic.


Assuntos
Spheniscidae , Animais , Conteúdo Gastrointestinal , Argentina , Poluição Ambiental , Plásticos
3.
Mar Pollut Bull ; 166: 112232, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33725563

RESUMO

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 relating microplastic contamination in marine environments from Covid-19 related waste, there has been relatively less attention paid to the potential risk of macro-scale contaminants, such as protective face coverings. We suggest that Covid-19 related macro contaminants be considered in coastal marine risk assessments and urge further research on this topic.


Assuntos
COVID-19 , Spheniscidae , Animais , Brasil , Ingestão de Alimentos , Humanos , Pandemias , Plásticos , SARS-CoV-2
4.
Ecol Appl ; 29(1): e01826, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30601594

RESUMO

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 of this species, and to highlight the importance of considering sex-specific vital rates in demographic seabird studies. Like many other seabirds, Magellanic Penguins are long-lived, serially monogamous, and exhibit obligate biparental care. We found that the non-breeding-season survival of females was lower than that of males and that the magnitude of this bias was highest for juveniles. Biases in survival accumulated as cohorts aged, leading to increasingly skewed sex ratios. The survival bias was greatest in years when overall survival was low, that is, females fared disproportionality worse when conditions were unfavorable. Our model-estimated survival patterns are consistent with independent data on carcasses from the species' non-breeding grounds, showing that mortality is higher for juveniles than for adults and higher for females than for males. Juveniles may be less efficient foragers than adults are and, because of their smaller size, females may show less resilience to food scarcity than males. We used perturbation analysis of a population matrix model to determine the impact of sex-biased survival on adult sex ratio and population growth rate at Punta Tombo. We found that adult sex ratio and population growth rate have the greatest proportional response, that is, elasticity, to female pre-breeder and adult survival. Sex bias in juvenile survival (i.e., lower survival of females) made the greatest contribution to population declines from 1990 to 2009. Because starvation is a leading cause of morality in juveniles and adults, precautionary fisheries and spatial management in the region could help to slow population decline. Our data add to growing evidence that knowledge of sex-specific demography and sex ratios are necessary for accurate assessment of seabird population trends.


Assuntos
Spheniscidae , Animais , Argentina , Feminino , Pesqueiros , Masculino , Dinâmica Populacional , Sexismo
5.
Acta toxicol. argent ; 24(2): 87-96, set. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-837856

RESUMO

Los pingüinos de Magallanes son entre las aves marinas, la especie más afectada por la contaminación con petróleo en Chubut y Santa Cruz. Una de las consecuencias adversas de la exposición a hidrocarburos y otros contaminantes es el aumento de los niveles celulares de especies reactivas del oxígeno o estrés oxidativo, considerados herramientas útiles como biomarcadores del impacto de la exposición a contaminantes químicos peligrosos. El objetivo de este trabajo fue evaluar parámetros hematológicos y marcadores de estrés oxidativo durante la rehabilitación de tres pingüinos empetrolados provenientes del Área Natural Protegida Punta Tombo, Chubut, Argentina. Se tomaron tres muestras de sangre por individuo: la primera muestra al arribo de los pingüinos al centro de rehabilitación, la segunda una semana después y una última muestra antes de ser liberados. Se obtuvieron la cantidad total de leucocitos, la razón heterófilos/linfocitos, el hematocrito y las concentraciones de glucosa y de proteínas totales. Se analizó la actividad de la enzima catalasa, responsable de la degradación del peróxido de hidrógeno, los niveles de tioles totales no proteicos y el daño a lípidos evaluando las especies reactivas al ácido tiobarbitúrico, como indicadores de estrés oxidativo. El estudio se complementó con la obtención del peso de los pingüinos. En general, los parámetros medidos, aumentaron o se mantuvieron constantes desde la primera toma de muestra hasta la última. Si bien algunas de las variables para cada pingüino se comportaron diferentes durante el tratamiento, en general se observó una tendencia a normalizarse hacia el momento de su liberación. Se concluye que los pingüinos se liberaron en buen estado físico luego de la rehabilitación.


Magellanic penguins are among the most affected seabirds by oil contamination in Patagonia. Hydrocarbons and other pollutants cause an increase in the cellular levels of reactive oxygen species that lead oxidative stress and in this way, the evaluation of oxidative stress parameters could be useful tools as biomarkers to evaluate the exposure to hazardous chemical contaminants. The aim of the present work was to evaluate hematological parameters and oxidative stress biomarkers during the rehabilitation of three oil-spill penguins from Punta Tombo Natural Protected Area in Chubut, Argentina. Three blood samples were taken from each individual, the first sample was obtained at arrival of penguin to the rehabilitation center, the second one was the following one week and last sample was taken before animals were freed. Hematocrit, white blood cell count, heterophil/ lymphocyte ratio as a measure of stress, and concentrations of glucose and total proteins were determined. The thiobarbituric acid reactive species, a well-established method for monitoring lipid peroxidation, the activity of catalase enzyme (involved in the catabolism of hydrogen peroxide) and the thiol levels were evaluated as oxidative stress indicators. In general, the measured parameters remained constant or increased their values from the first to the last blood sampling. While some of the variables for each penguin behaved differently during treatment, generally they tended to normalize when penguins were released. We conclude that penguins were released in good physical condition after rehabilitation.


Assuntos
Animais , Estresse Oxidativo , Poluição por Petróleo/efeitos adversos , Spheniscidae/sangue , Argentina , Biomarcadores/análise , Ecotoxicologia/métodos
6.
Pesqui. vet. bras ; 36(supl.1): 65-70, June 2016. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: lil-798006

RESUMO

Este trabalho apresenta valores hematológicos e bioquímicos de pinguins-de-Magalhães (Spheniscus magellanicus) juvenis que arribaram no Espírito Santo e Rio de Janeiro, litoral sudeste do Brasil, e foram encaminhados a reabilitação. Os valores médios obtidos foram: eritrócitos 2.55±0.54 milhões/µL; hemoglobina 13,37±3,91g/dL; hematócrito 41,5±0,04%; proteína plasmática 6,34±0,81g/dL; leucócitos 16.301±6.402/µL; trombócitos 20.516±4.591 células/µL; volume corpuscular médio (VCM) 172,0±53,0 fL; concentração de hemoglobina corpuscular média (CHCM) 26,41±0,02%; alanina transaminase (ALT) 50,0±17,89 U/L; ácido úrico 8,93±3,0mg/dL; albumina 1,68±0,53g/dL; cálcio 9,7±0,57mg/dL; fósforo 10,39±8,5mg/dL e glicose 211,6±30,3mg/dL. Valores de eritrócitos, VCM e CHCM foram discrepantes em relação aos valores de referência atuais. Valores de leucócitos e trombócitos tem significado inconclusivo. Hematócrito, hemoglobina, proteína plasmática e valores bioquímicos forneceram importante contribuição para o estabelecimento de parâmetros de referência.(AU)


This paper reports hematological and biochemical values of juveniles Magellanic penguins (Spheniscus magellanicus) stranded in Espírito Santo and Rio de Janeiro, Southeastern Brazil, that were sent for rehabilitation. The average values were: erythrocytes 2.55±0,54 milhões/µL, hemoglobin 13.37±3,91g/dL, hematocrit 41.5±0.04%, plasma protein 6.34±0.81g/dL, leukocytes 16,301±6,402/µL, thrombocytes 20,516±4,591 células/µL3, mean cell volume (MCV) 172.0±53.0 fL, mean cell hemoglobin concentration (MCHC) 26.41±0.02%, alanine transaminase (ALT) 50.0±17.89 U/L, uric acid 8.93±3.0mg/dL, albumin 1.68±0.53mg/dL, calcium 9.7±0.57mg/dL, phosphorus 10.39±8.5mg/dL and glucose 211.6±30.3mg/dL. Values of erythrocytes, MCV and MCH were discrepant in relation to the current reference values. Leukocytes and thrombocytes values has meant inconclusive. Hematocrit, hemoglobin, plasma protein and biochemical values provided important contribution for the establishment of reference parameters.(AU)


Assuntos
Animais , Fenômenos Bioquímicos , Análise Química do Sangue/veterinária , Reabilitação , Spheniscidae/sangue , Testes Hematológicos/veterinária
7.
J Zoo Wildl Med ; 47(1): 364-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27010304

RESUMO

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 sexed (male, female, or not identified), and data were analyzed using the chi-square test (P ≤ 0.05). Toxoplasma gondii antibodies were found in 28% of penguins: 25.8% males, 27.8% females, 30.3% unknown sex, 25.4% young, and 31.1% adults. Statistical analyses did not find any difference (P > 0.05) with respect to age, sex, or source of birds. This is the first report of T. gondii antibodies in S. magellanicus.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças das Aves/parasitologia , Spheniscidae , Toxoplasma/imunologia , Toxoplasmose Animal/sangue , Animais , Doenças das Aves/sangue , Doenças das Aves/imunologia , Feminino , Masculino , Toxoplasmose Animal/imunologia
8.
J Zoo Wildl Med ; 46(4): 667-74, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26667521

RESUMO

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 were categorized according to the outcome "aspergillosis," and analyzed by age group, sex, oil fouling, origin, prophylactic administration of itraconazole, period in captivity, body mass, hematocrit, and total plasma proteins. A total of 327 Magellanic penguins (Spheniscus magellanicus) was studied, 66 of which died of aspergillosis. Proportionate mortality by aspergillosis was 48.5%, and incidence density was 7.3 lethal aspergillosis cases per 100 penguins/mo. Approximately 75% of the aspergillosis cases occurred in penguins that had been transferred from other rehabilitation centers, and this was considered a significant risk factor for the disease. Significant differences were also observed between the groups in regard to the period of time spent in captivity until death, hematocrit and total plasma proteins upon admission to the center, and body mass gain during the period in captivity. The findings demonstrate the negative impacts of aspergillosis on the rehabilitation of Magellanic penguins, with a high incidence density and substantial mortality.


Assuntos
Aspergilose/veterinária , Doenças das Aves/microbiologia , Spheniscidae , Animais , Aspergilose/epidemiologia , Aspergilose/microbiologia , Aspergilose/mortalidade , Doenças das Aves/epidemiologia , Doenças das Aves/mortalidade , Brasil/epidemiologia , Estudos de Coortes , Incidência , Estudos Retrospectivos , Fatores de Risco
9.
Arq. bras. med. vet. zootec ; 65(1): 47-54, fev. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-667535

RESUMO

The bumblefoot or pododermatitis is among the diseases with the highest morbidity in Magellanic penguins, sometimes evolving to septicemia and death. Therefore, this study aimed to relate the main species involved in the disorder, as well as the in vitro susceptibility profile of the microorganisms against routine antimicrobial usage in Veterinary Medicine. During two years in vivo material was harvested from 200 footpads (n=100 animals) for microbiological analysis and in vitro susceptibility tests against the Antibiotic enrofloxacin, streptomycin, penicillin and cephalosporin. Bacteria have been identified both as part of permanent and transient microbiota, also being associated to 100% of the pododermatitis cases. The most prevalent genus were Staphylococcus and Corynebacterium. The antibiograms of all the isolated bacteria resulted in greater susceptibility of the strains facing cephalosporin, followed by enrofloxacin, streptomycin and penicillin.


O bumblefoot ou pododermatite está entre as afecções de maior morbidade em pinguins-de-magalhães, podendo evoluir para septicemia e óbito. Portanto, o presente estudo objetivou relacionar as principais espécies bacterianas envolvidas na afecção, bem como o perfil de susceptibilidade in vitro destes microrganismos frente a antimicrobianos de uso rotineiro em medicina veterinária. Durante o período de dois anos, foi realizada colheita de material in vivo de 200 coxins plantares (n=100 animais) para análise microbiológica e testes de susceptibilidade in vitro frente aos antibióticos enrofloxacina, estreptomicina, penicilina e cefalosporina. Bactérias foram identificadas tanto como parte da microbiota permanente quanto da transitória, bem como estiveram associadas a 100% dos casos de pododermatite. Os gêneros mais prevalentes foram Staphylococcus e Corynebacterium. Os antibiogramas de todas as bactérias isoladas resultaram em maior sensibilidade das cepas frente à cefalosporina, seguida de enrofloxacina, estreptomicina e penicilina.


Assuntos
Animais , Bactérias/crescimento & desenvolvimento , Bactérias/patogenicidade , Sepse/patologia , Sepse/veterinária , Spheniscidae/anormalidades , Spheniscidae/crescimento & desenvolvimento , Spheniscidae/lesões
10.
Braz. arch. biol. technol ; 55(4): 537-542, July-Aug. 2012.
Artigo em Inglês | LILACS | ID: lil-645405

RESUMO

To investigate the exposure of the Newcastle disease virus (NDV), infectious bursal disease virus (IBDV) and avian poxvirus (APV) in Magellanic penguins found on the beaches in Southern regions of Brazil, the frequency of serum antibodies was estimated in 89 samples taken during 2005 and 2006. All the penguins were negative for the presence of antibodies against NDV by hemagglutination inhibition test and to APV by indirect ELISA. The reactivity was similar to the positives controls using ELISA kit for the IBDV made in the chickens in 50 samples. This reactivity also was demonstrated in 42 samples using agar gel immunodiffusion. No clinical signs related to IBDV infection were observed. The results indicated the absence of infection by NDV and APV but suggested IBDV exposure in the population of penguins studied.

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