Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 1.129
1.
J Zoo Wildl Med ; 55(2): 479-489, 2024 Jun.
Article En | MEDLINE | ID: mdl-38875206

Aspergillosis is a major cause of morbidity and mortality in penguins, with triazole antifungal drugs being commonly used for prophylaxis and treatment. This report describes 15 cases of fatal hemolysis associated with liquid itraconazole and voriconazole formulations administered to African penguins (Spheniscus demersus) from four institutions. All penguins underwent stressful events (e.g. relocation, induced molt) and were administered commercial liquid itraconazole formulations or compounded voriconazole liquid suspension. Observed clinical signs in affected penguins prior to death included hyporexia, weight loss, lethargy, dyspnea, red-tinged droppings, and obtunded mentation. Intra- and extravascular hemolysis and hemoglobinuric nephrosis were the primary pathologic manifestations on postmortem examination. The concentration-dependent hemolytic potentials of itraconazole, voriconazole, and commercial and compounded vehicle suspensions were evaluated in vitro by exposing chicken whole blood as a surrogate for penguin blood. Hemoglobin content in blood plasma was then measured by spectrophotometry. Neither itraconazole nor voriconazole alone induced hemolysis in vitro. The vehicle ingredients sorbitol and hydromellose induced hemolysis, but not at predicted plasma levels in chicken erythrocytes, suggesting neither the azole antifungals nor their major vehicles alone were likely to contribute to hemolysis in vivo in these penguins. Potential mechanisms of toxicosis include generation of an unmeasured reactive metabolite causing hemolysis, preexisting erythrocyte fragility, or species-specific differences in hemolytic thresholds that were not assessed in the chicken erythrocyte model. More research is needed on the potential for toxicosis of azole antifungal drugs and carrier molecules in this and other avian species.


Antifungal Agents , Bird Diseases , Hemolysis , Spheniscidae , Voriconazole , Animals , Bird Diseases/chemically induced , Bird Diseases/drug therapy , Hemolysis/drug effects , Antifungal Agents/adverse effects , Antifungal Agents/therapeutic use , Antifungal Agents/administration & dosage , Voriconazole/adverse effects , Voriconazole/therapeutic use , Itraconazole/adverse effects , Itraconazole/therapeutic use , Itraconazole/administration & dosage , Triazoles/adverse effects , Triazoles/therapeutic use , Male , Female , Animals, Zoo
2.
J Exp Biol ; 227(11)2024 Jun 01.
Article En | MEDLINE | ID: mdl-38826104

Once a year, penguins undergo a catastrophic moult, replacing their entire plumage during a fasting period on land or on sea-ice during which time individuals can lose 45% of their body mass. In penguins, new feather synthesis precedes the loss of old feathers, leading to an accumulation of two feather layers (double coat) before the old plumage is shed. We hypothesized that the combination of the high metabolism required for new feather synthesis and the potentially high thermal insulation linked to the double coat could lead to a thermal challenge requiring additional peripheral circulation to thermal windows to dissipate the extra heat. To test this hypothesis, we measured the surface temperature of different body regions of captive gentoo penguins (Pygoscelis papua) throughout the moult under constant environmental conditions. The surface temperature of the main body trunk decreased during the initial stages of the moult, suggesting greater thermal insulation. In contrast, the periorbital region, a potential proxy of core temperature in birds, increased during these same early moulting stages. The surface temperature of the bill, flipper and foot (thermal windows) tended to initially increase during the moult, highlighting the likely need for extra heat dissipation in moulting penguins. These results raise questions regarding the thermoregulatory capacities of penguins in the wild during the challenging period of moulting on land in the current context of global warming.


Body Temperature , Feathers , Molting , Spheniscidae , Animals , Spheniscidae/physiology , Molting/physiology , Feathers/physiology , Body Temperature Regulation/physiology , Male , Female
3.
PLoS One ; 19(6): e0303834, 2024.
Article En | MEDLINE | ID: mdl-38837960

We derive an equation that applies for the wing-beat frequency of flying animals and to the fin-stroke frequency of diving animals like penguins and whales. The equation states that the wing/fin-beat frequency is proportional to the square root of the animal's mass divided by the wing area. Data for birds, insects, bats, and even a robotic bird-supplemented by data for whales and penguins that must swim to stay submerged-show that the constant of proportionality is to a good approximation the same across all species; thus the equation is universal. The wing/fin-beat frequency equation is derived by dimensional analysis, which is a standard method of reasoning in physics. We finally demonstrate that a mathematically even simpler expression without the animal mass does not apply.


Flight, Animal , Wings, Animal , Animals , Wings, Animal/physiology , Wings, Animal/anatomy & histology , Flight, Animal/physiology , Animal Fins/physiology , Chiroptera/physiology , Whales/physiology , Spheniscidae/physiology , Birds/physiology , Models, Biological , Swimming/physiology , Insecta/physiology
4.
Prev Vet Med ; 227: 106206, 2024 Jun.
Article En | MEDLINE | ID: mdl-38696942

The highly pathogenic Avian Influenza virus (HPAIV) H5N1 has caused a global outbreak affecting both wild and domestic animals, predominantly avian species. To date, cases of the HPAIV H5 Clade 2.3.4.4b in penguins have exclusively been reported in African Penguins. In Chile, the virus was confirmed in pelicans in December 2022 and subsequently spread across the country, affecting several species, including Humboldt penguins. This study aims to provide an overview of the incidents involving stranded and deceased Humboldt penguins and establish a connection between these events and HPAIV H5N1. Historical data about strandings between 2009 and 2023 was collected, and samples from suspected cases in 2023 were obtained to confirm the presence of HPAIV H5N1. Between January and August 2023, 2,788 cases of stranded and deceased penguins were recorded. Out of these, a total of 2,712 penguins deceased, evidencing a significative increase in mortality starting in early 2023 coinciding with the introduction and spreading of HPAIV H5N1 in the country. Thirty-seven events were categorized as mass mortality events, with the number of deceased penguins varying from 11 to 98. Most cases (97 %) were observed in the North of Chile. One hundred and eighty-one specimens were subjected to HPAIV diagnosis, four of which tested positive for HPAIV H5N1. Spatial analysis validates the correlation between mass mortality events and outbreaks of HPAIV in Chile. However, the limited rate of HPAIV H5N1 detection, which can be attributed to the type and quality of the samples, requiring further exploration.


Disease Outbreaks , Influenza A Virus, H5N1 Subtype , Influenza in Birds , Spheniscidae , Animals , Spheniscidae/virology , Chile/epidemiology , Disease Outbreaks/veterinary , Influenza in Birds/epidemiology , Influenza in Birds/virology , Influenza in Birds/mortality
5.
Fish Shellfish Immunol ; 149: 109574, 2024 Jun.
Article En | MEDLINE | ID: mdl-38692379

B-cell lymphoma/leukemia-2 (BCL2), an anti-apoptotic factor in the mitochondrial regulatory pathway of apoptosis, is critically important in immune defenses. In this study, a novel BCL2 gene was characterized from Pteria penguin (P. penguin). The PpBCL2 was 1482 bp long, containing an open reading frame (ORF) of 588 bp encoding 195 amino acids. Four highly conserved BCL-2 homology (BH) domains were found in PpBCL2. Amino acid alignment and phylogenetic tree showed that PpBCL2 had the highest similarity with BCL2 of Crassostrea gigas at 65.24 %. Tissue expression analysis showed that PpBCL2 had high constitutive expression in gill, digestive diverticulum and mantle, and was significantly increased 72 h of Vibrio parahaemolyticus (V. parahaemolyticus) challenge in these immune tissues. Furthermore, PpBCL2 silencing significantly inhibited antimicrobial activity of hemolymph supernatant by 1.4-fold, and significantly reduced the survival rate by 51.7 % at 72 h post infection in P. penguin. These data indicated that PpBCL2 played an important role in immune response of P. penguin against V. parahaemolyticus infection.


Amino Acid Sequence , Immunity, Innate , Phylogeny , Proto-Oncogene Proteins c-bcl-2 , Sequence Alignment , Spheniscidae , Vibrio parahaemolyticus , Animals , Vibrio parahaemolyticus/physiology , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/immunology , Spheniscidae/immunology , Spheniscidae/genetics , Sequence Alignment/veterinary , Immunity, Innate/genetics , Gene Expression Regulation/immunology , Gene Expression Profiling/veterinary , Vibrio Infections/immunology , Vibrio Infections/veterinary , Base Sequence
6.
Nat Commun ; 15(1): 4419, 2024 May 29.
Article En | MEDLINE | ID: mdl-38811565

Emperor penguins (Aptenodytes forsteri) are under increasing environmental pressure. Monitoring colony size and population trends of this Antarctic seabird relies primarily on satellite imagery recorded near the end of the breeding season, when light conditions levels are sufficient to capture images, but colony occupancy is highly variable. To correct population estimates for this variability, we develop a phenological model that can predict the number of breeding pairs and fledging chicks, as well as key phenological events such as arrival, hatching and foraging times, from as few as six data points from a single season. The ability to extrapolate occupancy from sparse data makes the model particularly useful for monitoring remotely sensed animal colonies where ground-based population estimates are rare or unavailable.


Remote Sensing Technology , Spheniscidae , Animals , Spheniscidae/physiology , Remote Sensing Technology/methods , Breeding , Antarctic Regions , Seasons , Reproduction/physiology , Population Density , Population Dynamics , Female
7.
J Vet Med Sci ; 86(6): 708-711, 2024 Jun 19.
Article En | MEDLINE | ID: mdl-38719569

A 21-year-old captive female Humboldt penguin (Spheniscus humboldti) was in good health until the day before the animal died. However, the animal suddenly exhibited symptoms of vomiting and anorexia, and died in shortly thereafter. The autopsy revealed a blood clot in the abdominal air sac and 280 mL of dark red fluid in the body cavity. The ovary was twisted around a blood vessel. Based on the findings described, it was considered that the cause of death was hypovolemic shock due to massive intracoelomic hemorrhage by vascular collapse resulting from ovarian torsion. This is the first report of ovarian torsion in penguins.


Bird Diseases , Hemorrhage , Ovarian Torsion , Shock, Hemorrhagic , Spheniscidae , Animals , Female , Shock, Hemorrhagic/veterinary , Shock, Hemorrhagic/etiology , Bird Diseases/pathology , Hemorrhage/veterinary , Hemorrhage/etiology , Hemorrhage/pathology , Ovarian Torsion/veterinary , Ovarian Torsion/complications , Fatal Outcome , Animals, Zoo
8.
Environ Toxicol Chem ; 43(6): 1442-1457, 2024 Jun.
Article En | MEDLINE | ID: mdl-38695731

Microplastic pollution threatens some of the world's most iconic locations for marine biodiversity, including the remote Galápagos Islands, Ecuador. Using the Galápagos penguin (Spheniscus mendiculus) as a sentinel species, the present study assessed microplastics and suspected anthropogenic cellulose concentrations in surface seawater and zooplankton near Santa Cruz and Galápagos penguin colonies (Floreana, Isabela, Santiago), as well as in penguin potential prey (anchovies, mullets, milkfish) and penguin scat. On average, 0.40 ± 0.32 microplastics L-1 were found in surface seawater (<10 µm; n = 63 L), while 0.003, 0.27, and 5.12 microplastics individual-1 were found in zooplankton (n = 3372), anchovies (n = 11), and mullets (n = 6), respectively. The highest concentration (27 microplastics individual-1) was observed in a single milkfish. Calculations based on microplastics per gram of prey, in a potential diet composition scenario, suggest that the Galápagos penguin may consume 2881 to 9602 microplastics daily from prey. Despite this, no microplastics or cellulose were identified in 3.40 g of guano collected from two penguins. Our study confirms microplastic exposure in the pelagic food web and endangered penguin species within the UNESCO World Heritage site Galápagos Islands, which can be used to inform regional and international policies to mitigate plastic pollution and conserve biodiversity in the global ocean. Environ Toxicol Chem 2024;43:1442-1457. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Cellulose , Environmental Monitoring , Food Chain , Microplastics , Spheniscidae , Water Pollutants, Chemical , Animals , Microplastics/toxicity , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity , Ecuador , Zooplankton/drug effects , Seawater/chemistry
9.
J Avian Med Surg ; 38(1): 1-6, 2024 Apr.
Article En | MEDLINE | ID: mdl-38686882

Electrophoresis is a useful diagnostic tool for detecting inflammation, including inflammation associated with infectious diseases (eg, aspergillosis in penguins). To our knowledge, reference intervals are not available for plasma proteins via electrophoresis in Humboldt penguins (Spheniscus humboldti). Therefore, preliminary reference intervals for blood plasma proteins measured by capillary zone electrophoresis were calculated for Humboldt penguins from a single zoological collection, and possible differences between the sexes and the ages of the birds were evaluated. Lithium heparinized plasma samples from 39 Humboldt penguins were analyzed. The following sex- and age-independent reference intervals were calculated: total protein 33.8-70.4 g/L, prealbumin 1.9-4.9 g/L, albumin 12.9-31.1 g/L, albumin: globulin ratio 0.7-1.7, α-globulins 4.5-11.6 g/L, ß-globulins 5.6-20.6 g/L, and γ-globulins 2.6-8.4 g/L. Male penguins had a significantly (P = 0.047) higher albumin: globulin ratio and lower percentage of ß-globulins (P = 0.015) in comparison with female penguins. Prealbumin (g/L) significantly (P = 0.021) decreased with increased age of the penguins. These results showed some differences between the sexes and ages of the penguins, which should be considered when interpreting the results. Further studies are needed to determine whether differences in other age groups or seasons exist, and also to evaluate which infectious diseases affect plasma proteins and how the reference values calculated here may deviate in ill penguins.


Electrophoresis, Capillary , Spheniscidae , Animals , Spheniscidae/blood , Male , Female , Reference Values , Electrophoresis, Capillary/veterinary , Blood Proteins/analysis
10.
Biol Open ; 13(5)2024 May 15.
Article En | MEDLINE | ID: mdl-38639412

Penguins are proficient swimmers, and their survival depends on their ability to catch prey. The diving behaviour of these fascinating birds should then minimize the associated energy cost. For the first time, the energy cost of penguin dives is computed from the free-ranging dive data, on the basis of an existing biomechanical model. Time-resolved acceleration and depth data collected for 300 dives of little penguins (Eudyptula minor) are specifically employed to compute the bird dive angles and swimming speeds, which are needed for the energy estimate. We find that the numerically obtained energy cost by using the free-ranging dive data is not far from the minimum cost predicted by the model. The outcome, therefore, supports the physical soundness of the chosen model; however, it also suggests that, for closer agreement, one should consider previously neglected effects, such as those due to water currents and those associated with motion unsteadiness. Additionally, from the free-ranging dive data, we calculate hydrodynamic forces and non-dimensional indicators of propulsion performance - Strouhal and Reynolds numbers. The obtained values further confirm that little penguins employ efficient propulsion mechanisms, in agreement with previous investigations.


Diving , Spheniscidae , Swimming , Animals , Spheniscidae/physiology , Biomechanical Phenomena , Diving/physiology , Swimming/physiology , Locomotion/physiology , Energy Metabolism
11.
Ambio ; 53(7): 1037-1049, 2024 Jul.
Article En | MEDLINE | ID: mdl-38589654

Conserving landscapes used by multiple stakeholder groups requires understanding of what each stakeholder values. Here we employed a semi-structured, participatory approach to identify features of value in the terrestrial Antarctic Peninsula related to biodiversity, science and tourism. Stakeholders identified 115 features, ranging from Adélie penguin colonies to sites suitable for snowshoeing tourists. We split the features into seven broad categories: science, tourism, historic, biodiversity, geographic, habitat, and intrinsic features, finding that the biodiversity category contained the most features of any one category, while science stakeholders identified the most features of any stakeholder group. Stakeholders have overlapping interests in some features, particularly for seals and seabirds, indicating that thoughtful consideration of their inclusion in future management is required. Acknowledging the importance of tourism and other social features in Antarctica and ensuring their integration into conservation planning and assessment will increase the likelihood of implementing successful environmental management strategies into the future.


Biodiversity , Conservation of Natural Resources , Antarctic Regions , Animals , Ecosystem , Spheniscidae , Tourism , Birds
12.
Braz J Microbiol ; 55(2): 1521-1528, 2024 Jun.
Article En | MEDLINE | ID: mdl-38649623

Aspergillus fumigatus is a common opportunistic pathogen in different animals, including birds such as penguins. For the first time, a fungal strain identified as A. fumigatus was isolated from soil in the nests of gentoo penguins, Pygoscelis papua, on Livingston Island, South Shetland Islands (maritime Antarctica). This isolate (A. fumigatus UFMGCB 11829) displayed a series of potentially pathogenic characteristics in vitro. We evaluated its detailed molecular taxonomy and submitted the A. fumigatus UFMGCB 11829 Antarctic strain to in vivo pathogenic modelling. The isolate was confirmed to represent A. fumigatus morphological and phylogenetic analysis showed that it was closely related to A. fumigatus sequences reported from animals, immunosuppressed humans, storage grains, plants and soils. The strain displayed the best mycelial growth and conidia production at 37 ºC; however, it was also able to grow and produce conidia at 15º, demonstrating its capability to survive and colonize penguin nest at least in the summer season in maritime Antarctica. In pathogenicity tests, healthy mice did not showed symptoms of infection; however, 50% lethality was observed in immunosuppressed mice that were inoculated with 106 and 107 spores. Lethality increased to 100% when inoculated with 108 spores. Our data highlight the potential pathogenicity of opportunistic A. fumigatus that may be present in the Antarctic, and the risks of both their further transfer within Antarctica and outwards to other continents, risks which may be exacerbated due global climatic changes.


Aspergillosis , Aspergillus fumigatus , Phylogeny , Soil Microbiology , Spheniscidae , Animals , Spheniscidae/microbiology , Antarctic Regions , Aspergillus fumigatus/genetics , Aspergillus fumigatus/isolation & purification , Aspergillus fumigatus/classification , Aspergillus fumigatus/pathogenicity , Mice , Aspergillosis/microbiology , Aspergillosis/veterinary , Bird Diseases/microbiology , Virulence
13.
J Therm Biol ; 121: 103850, 2024 Apr.
Article En | MEDLINE | ID: mdl-38608548

Assessing the physiological stress responses of wild animals opens a window for understanding how organisms cope with environmental challenges. Since stress response is associated with changes in body temperature, the use of body surface temperature through thermal imaging could help to measure acute and chronic stress responses non-invasively. We used thermal imaging, acute handling-stress protocol and an experimental manipulation of corticosterone (the main glucocorticoid hormone in birds) levels in breeding king penguins (Aptenodytes patagonicus), to assess: 1. The potential contribution of the Hypothalamo-Pituitary-Adrenal (HPA) axis in mediating chronic and acute stress-induced changes in adult surface temperature, 2. The influence of HPA axis manipulation on parental investment through thermal imaging of eggs and brooded chicks, and 3. The impact of parental treatment on offspring thermal's response to acute handling. Maximum eye temperature (Teye) increased and minimum beak temperature (Tbeak) decreased in response to handling stress in adults, but neither basal nor stress-induced surface temperatures were significantly affected by corticosterone implant. While egg temperature was not significantly influenced by parental treatment, we found a surprising pattern for chicks: chicks brooded by the (non-implanted) partner of corticosterone-implanted individuals exhibited higher surface temperature (both Teye and Tbeak) than those brooded by glucocorticoid-implanted or control parents. Chick's response to handling in terms of surface temperature was characterized by a drop in both Teye and Tbeak independently of parental treatment. We conclude that the HPA axis seems unlikely to play a major role in determining chronic or acute changes in surface temperature in king penguins. Changes in surface temperature may primarily be mediated by the Sympathetic-Adrenal-Medullary (SAM) axis in response to stressful situations. Our experiment did not reveal a direct impact of parental HPA axis manipulation on parental investment (egg or chick temperature), but a potential influence on the partner's brooding behaviour.


Corticosterone , Hypothalamo-Hypophyseal System , Spheniscidae , Stress, Physiological , Animals , Spheniscidae/physiology , Spheniscidae/blood , Corticosterone/blood , Hypothalamo-Hypophyseal System/physiology , Hypothalamo-Hypophyseal System/metabolism , Female , Male , Pituitary-Adrenal System/physiology , Pituitary-Adrenal System/metabolism , Body Temperature
14.
Behav Processes ; 218: 105032, 2024 May.
Article En | MEDLINE | ID: mdl-38657758

Group-living animals, including penguins, exhibit affiliative behaviors such as grooming (preening) and proximity. Such behaviors in non-primate animals have been less studied than those in primates. Our research focused on 20 identifiable Humboldt penguins in a zoo, analyzing kin relationships and reciprocity in preening and proximity by employing a 5-minute scan sampling method to observe and record individual behavior. Our findings revealed that preening and proximity were more prevalent among mate pairs. However, among non-mate pairs, such behaviors were more commonly observed between siblings and parent-offspring pairs. Notably, the individuals preened on each other simultaneously in all instances. This study highlights the potential influence of kin selection in shaping the affiliative behavior of penguins. Additionally, our findings indicate that penguins gain benefits from mutual preening. This study contributes to our understanding of social behaviors in non-primate species and emphasizes the need for further comparative studies of various animal taxa to elucidate the evolution of sociality.


Animals, Zoo , Grooming , Social Behavior , Spheniscidae , Animals , Spheniscidae/physiology , Grooming/physiology , Male , Female , Behavior, Animal/physiology
15.
Support Care Cancer ; 32(4): 225, 2024 Mar 13.
Article En | MEDLINE | ID: mdl-38472496

BACKGROUND: Scalp cooling is an increasingly recognized non-pharmacologic approach to minimize chemotherapy-induced alopecia (CIA). Several commercially available machine-based and manual scalp cooling systems are available; however, literature reports of effectiveness are highly variable. The purpose of this study was to determine real-world tolerability and subjective effectiveness of a manual cold capping system in minimizing CIA across a variety of patient race and hair types. This study was a single-institution review of outcomes from manual cold capping. METHODS: We identified retrospective cohort of adult patients who presented to discuss cold capping between January 14, 2019, and March 31, 2022. Data collected from medical records included demographics, decision to pursue/continue cold capping, diagnoses, chemotherapy regimens, hair characteristics (length, thickness, coarseness, type), and subjective perception of percentage of hair retained. Those with successful vs. unsuccessful cold capping (≥ 50% vs. < 50% of hair retained) were compared based on the patient-level factors of interest. FINDINGS: A total of 100 patients initiated cold capping during the study period, and 95% of them completed cold capping. The majority of patients who started cold capping completed it. The median-reported percentage of hair maintained was 75%, and 82/89 (92.1% of patients) had favorable results, defined as ≥ 50% of hair retained. The only patient-level factor associated with favorable response was chemotherapy regimen, with fewer patients receiving doxorubicin-containing regimens having successful hair retention compared to other chemotherapy types (71.4% successful results vs. 95.7% for those receiving paclitaxel-containing regimens and 96.6% for those receiving docetaxel-containing regimens (p = 0.018). There was no difference in success based on patient race/ethnicity or hair characteristics. INTERPRETATION: The overall effectiveness (92.1%) in this study is consistent to higher than many literature reports. One possible reason for the high success in our cohort is compliance with cold capping protocols, meaning applying the cap in the appropriate manner and wearing the cap for the prescribed durations, which may impact effectiveness.


Antineoplastic Agents , Hypothermia, Induced , Spheniscidae , Adult , Animals , Humans , Hypothermia, Induced/methods , Retrospective Studies , Scalp , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Alopecia/chemically induced , Antineoplastic Agents/adverse effects
16.
Proc Biol Sci ; 291(2018): 20232067, 2024 Mar 13.
Article En | MEDLINE | ID: mdl-38471550

Like many polar animals, emperor penguin populations are challenging to monitor because of the species' life history and remoteness. Consequently, it has been difficult to establish its global status, a subject important to resolve as polar environments change. To advance our understanding of emperor penguins, we combined remote sensing, validation surveys and using Bayesian modelling, we estimated a comprehensive population trajectory over a recent 10-year period, encompassing the entirety of the species' range. Reported as indices of abundance, our study indicates with 81% probability that there were fewer adult emperor penguins in 2018 than in 2009, with a posterior median decrease of 9.6% (95% credible interval (CI) -26.4% to +9.4%). The global population trend was -1.3% per year over this period (95% CI = -3.3% to +1.0%) and declines probably occurred in four of eight fast ice regions, irrespective of habitat conditions. Thus far, explanations have yet to be identified regarding trends, especially as we observed an apparent population uptick toward the end of time series. Our work potentially establishes a framework for monitoring other Antarctic coastal species detectable by satellite, while promoting a need for research to better understand factors driving biotic changes in the Southern Ocean ecosystem.


Spheniscidae , Animals , Ecosystem , Bayes Theorem , Time Factors , Remote Sensing Technology , Antarctic Regions
17.
Environ Pollut ; 347: 123714, 2024 Apr 15.
Article En | MEDLINE | ID: mdl-38452836

Marine pollution is becoming ubiquitous in the environment. Observations of pollution on beaches, in the coastal ocean, and in organisms in the Antarctic are becoming distressingly common. Increasing human activity, growing tourism, and an expanding krill fishing industry along the West Antarctic Peninsula all represent potential sources of plastic pollution and other debris (collectively referred to as debris) to the region. However, the sources of these pollutants from point (pollutants released from discrete sources) versus non-point (pollutants from a large area rather than a specific source) sources are poorly understood. We used buoyant simulated particles released in a high-resolution physical ocean model to quantify pollutant loads throughout the region. We considered non-point sources of debris from the Antarctic Circumpolar Current, Bellingshausen Sea, Weddell Sea, and point source pollution from human activities including tourism, research, and fishing. We also determined possible origins for observed debris based on data from the Southern Ocean Observing System and Palmer Long-Term Ecological Research program. Our results indicate that point source pollution released in the coastal Antarctic is more likely to serve as a source for observed debris than non-point sources, and that the dominant source of pollution is region-specific. Penguin colonies in the South Shetland and Elephant Islands had the greatest debris load from point sources whereas loads from non-point sources were greatest around the southernmost colonies. Penguin colonies at Cornwallis Island and Fort Point were exposed to the highest theoretical debris loads. While these results do not include physical processes such as windage and Stokes Drift that are known to impact debris distributions and transport in the coastal ocean, these results provide critical insights to building an effective stratified sampling and monitoring effort to better understand debris distributions, concentrations, and origins throughout the West Antarctic Peninsula.


Environmental Pollutants , Spheniscidae , Animals , Humans , Antarctic Regions , Environmental Pollution , Environmental Monitoring/methods
18.
Sci Total Environ ; 923: 171345, 2024 May 01.
Article En | MEDLINE | ID: mdl-38447711

Recent studies have highlighted the presence of antibiotic resistance genes (ARGs) in Antarctica, which are typically indicative of human activity. However, these studies have concentrated in the Antarctic Peninsula region, and relatively less is known about ARG prevalence in East Antarctica, where human activity levels are lower compared to the Antarctic Peninsula. In addition, the mechanisms of ARG transmission to Antarctica through natural or anthropogenic pathways remain unclear. In this study, we analyzed the fecal samples of Adélie penguins and South polar skuas by using high-throughput sequencing and microfluidic quantitative PCR to detect potential pathogens and ARGs at their breeding colonies near Syowa Station in East Antarctica. These results revealed the presence of several potential pathogens in the fecal matter of both bird species. However, the HF183 marker, which indicates human fecal contamination, was absent in all samples, as well as seawater sampled near the breeding colonies. This suggests that the human fecal contamination was negligible in our study area. In addition to pathogens, we found a significant number of ARGs and metal resistance genes in the feces of both Adélie penguins and South polar skuas, with higher detection rates in skuas than in penguins. To better understand how these birds acquire and transmit these genes, we analyzed the migratory patterns of Adélie penguins and South polar skuas by geolocator tracking. We found that the skuas migrate to the tropical and subtropical regions of the Indian Ocean during the austral winter. On the other hand, Adélie penguins exhibited a more localized migration pattern, mainly staying within Antarctic waters. Because the Indian Ocean is considered one of the major reservoirs of ARGs, South polar skuas might be exposed to ARGs during their winter migration and transfer these genes to Antarctica.


Charadriiformes , Spheniscidae , Animals , Humans , Antarctic Regions , Spheniscidae/genetics , Seasons , Feces
19.
Sci Total Environ ; 922: 171249, 2024 Apr 20.
Article En | MEDLINE | ID: mdl-38431169

How Antarctic species are facing historical and new stressors remains under-surveyed and risks to wildlife are still largely unknown. Adélie penguins Pygoscelis adeliae are well-known bioindicators and sentinels of Antarctic ecosystem changes, a true canary in the coal mine. Immuno-haematological parameters have been proved to detect stress in wild animals, given their rapid physiological response that allows them tracking environmental changes and thus inferring habitat quality. Here, we investigated variation in Erythrocyte Nuclear Abnormalities (ENAs) and White Blood Cells (WBCs) in penguins from three clustered colonies in the Ross Sea, evaluating immuno-haematological parameters according to geography, breeding stage, and individual penguin characteristics such as sex, body condition and nest quality. Concentrations of mercury (Hg) and stable isotopes of carbon and nitrogen (as proxies of the penguin's trophic ecology) were analysed in feathers to investigate the association between stress biomarkers and Hg contamination in Adélie penguins. Colony and breeding stage were not supported as predictors of immuno-haematological parameters. ENAs and WBCs were respectively ∼30 % and ∼20 % higher in male than in female penguins. Body condition influenced WBCs, with penguins in the best condition having a ∼22 % higher level of WBCs than those in the worst condition. Nest position affected the proportion of micronuclei (MNs), with inner-nesting penguins having more than three times the proportion of MNs than penguins nesting in peripheral positions. Heterophils:Lymphocytes (H:L) ratio was not affected by any of the above predictors. Multiple factors acting as stressors are expected to increase prominently in Antarctic wildlife in the near future, therefore extensive monitoring aimed to assess the health status of penguin populations is mandatory.


Mercury , Spheniscidae , Animals , Male , Female , Ecosystem , Antarctic Regions , Ecology , Animals, Wild , Spheniscidae/physiology
20.
Oecologia ; 204(3): 675-688, 2024 Mar.
Article En | MEDLINE | ID: mdl-38459994

Anthropogenic activities generate increasing disturbance in wildlife especially in extreme environments where species have to cope with rapid environmental changes. In Antarctica, while studies on human disturbance have mostly focused on stress response through physiological and behavioral changes, local variability in population dynamics has been addressed more scarcely. In addition, the mechanisms by which breeding communities are affected around research stations remain unclear. Our study aims at pointing out the fine-scale impact of human infrastructures on the spatial variability in Adélie penguin (Pygoscelis adeliae) colonies dynamics. Taking 24 years of population monitoring, we modeled colony breeding success and growth rate in response to both anthropic and land-based environmental variables. Building density around colonies was the second most important variable explaining spatial variability in breeding success after distance from skua nests, the main predators of penguins on land. Building density was positively associated with penguins breeding success. We discuss how buildings may protect penguins from avian predation and environmental conditions. The drivers of colony growth rate included topographical variables and the distance to human infrastructures. A strong correlation between 1-year lagged growth rate and colony breeding success was coherent with the use of public information by penguins to select their initial breeding site. Overall, our study brings new insights about the relative contribution and ecological implications of human presence on the local population dynamics of a sentinel species in Antarctica.


Spheniscidae , Animals , Humans , Spheniscidae/physiology , Population Dynamics , Breeding , Antarctic Regions
...