Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program

In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point.

Assessment of trace metals in droppings of Adélie penguins(Pygoscelis adeliae) from different locations of the Antarctic Peninsula area

In recent decades, polar regions of the planet have witnessed an increase in human presence. Antarctica is considered one of the most pristine regions of the world, but it could be affected by pollution owing to anthropogenic activities, particularly in the Antarctic Peninsula. Human presence can increase the levels of some trace metals in Antarctic environments, an issue that needs to be evaluated. To acquire data of trace metal contamination in the Antarctic Peninsula region, concentrations （dry weight） of Cd, Pb, As, Cu, Hg and Zn in fresh excrement of Ad61ie penguins were determined by atomic absorption spectrophotometry. During the 2012/2013 austral summer, samples were collected from four important nesting sites on the Antarctic Peninsula： Arctowski Base, Kopaitic Island （both sites in the northern Antarctic Peninsula）, Yalour Island and Avian Island （both sites in the southern Antarctic Peninsula）. Data showed that Ad61ie penguin excreta had significantly higher levels （mg.kg~） of As, Cd, Hg, Pb and Cu at Arctowski Base and Kopaitic Island, both sites that have major anthropogenic activities that probably contributed to increased metal levels. The levels of trace metals in Ad61ie penguins were similar to those reported in excreta of Antarctic species in previous studies, and lower than those in excreta of other Antarctic animals. Data suggest that metals ingested by these penguin species that feed in the sea, end up in terrestrial ecosystems.

Distribution and reproductive behavior of penguins on Ardley Island and their environmental impact factors

During the 2006/07 Antarctic summer,the species population,distribution and reproductive behavior of penguins in areas near the Great Wall Station were investigated.Five species of penguin were recorded：gentoo penguin（Pygoscelis papua）,adelie penguin（P.adeliae）,chinstrap penguin（P.antarctica）, King penguin（Aptenodytes patagonicus） and Emperor penguin（A.forsteri）. The first three species bred locally,while the other two species were observed occasionally.Ardley Island is one of the most important breeding areas for penguins.After the breeding season of 2006/07,there were a total of about 17 234 penguins and the breeding success rate was 0.40—1.41.Comparing with historical data,changes in penguin species populations and distribution were analyzed, and their relationships with the environment,climate change and human activity were investigated.

Adélie penguins and temperature changes in Antarctica: a long-term view

During the summer months,Adélie penguins represent the dominant biomass of terrestrial Antarctica.Literally millions of individuals nest in ice-free areas around the coast of the continent.Hence,these modern populations of Adélie penguins have often been championed as an ideal biological indicator of ecological and environmental changes that we currently face.In addition,Adélie penguins show an extraordinary record of sub-fossil remains,dating back to the late Pleistocene.At this time,temperatures were much lower than now.Hence,this species of­fers unique long-term information,at both the genomic and ecological levels,about how a species has responded to climate change over more than 40000 years.

Analytical and Observational Investigation of Colors Effects on Drag Reduction in Penguins

All 18 extant species of penguin are strongly countershaded,having dark dorsal and light ventral coloration.In this paper,the thermal effects of this body color in penguins are investigated through analytical and observational analyses.First,a thermal analysis that takes into account the environmental characteristics of penguins’habitats,fluxes,and morphology is used to analytically calculate penguin dorsal surface temperature.Next,a turbulent analytical solution for a heated boundary layer over a flat plate is applied to show that the dark color on the top of the penguins’bodies is very effective at skin drag reduction.To verify this result,a 2D model penguin is computationally analyzed at different temperatures,confirming in principle underwater skin drag reduction through color-based surface warming with efficiency savings of up to 30%.Finally,to study how color-based increases in body surface temperatures are maintained through foraging dives,thermal cameras are used to measure the surface temperature of captive penguins before and after dives.This study shows conceptually that dark dorsal coloration in penguins could have a significant influence on in-water drag.

Leveraging Retinal Fundus Images with Deep Learning for Diabetic Retinopathy Grading and Classification

Recently,there has been a considerable rise in the number of diabetic patients suffering from diabetic retinopathy(DR).DR is one of the most chronic diseases and makes the key cause of vision loss in middle-aged people in the developed world.Initial detection of DR becomes necessary for decreasing the disease severity by making use of retinal fundus images.This article introduces a Deep Learning Enabled Large Scale Healthcare Decision Making for Diabetic Retinopathy(DLLSHDM-DR)on Retinal Fundus Images.The proposed DLLSHDM-DR technique intends to assist physicians with the DR decision-making method.In the DLLSHDM-DR technique,image preprocessing is initially performed to improve the quality of the fundus image.Besides,the DLLSHDM-DR applies HybridNet for producing a collection of feature vectors.For retinal image classification,the DLLSHDM-DR technique exploits the Emperor Penguin Optimizer(EPO)with a Deep Recurrent Neural Network(DRNN).The application of the EPO algorithm assists in the optimal adjustment of the hyperparameters related to the DRNN model for DR detection showing the novelty of our work.To assuring the improved performance of the DLLSHDMDR model,a wide range of experiments was tested on the EyePACS dataset.The comparison outcomes assured the better performance of the DLLSHDM-DR approach over other DL models.

Effective Energy Management Scheme by IMPC

The primary purpose of the Energy Management Scheme(EMS)is to monitor the energy fluctuations present in the load profile.In this paper,the improved model predictive controller is adopted for the EMS in the power system.Emperor Penguin Optimization(EPO)algorithm optimized Artificial Neural Network(ANN)with Model Predictive Control(MPC)scheme for accurate prediction of load and power forecasting at the time of preoptimizing EMS is presented.For the power generation,Renewable Energy Sources(RES)such as photo voltaic(PV)and wind turbine(WT)are utilized along with that the fuel cell is also presented in case of failure by the RES.Such a setup is connected with the grid and applies to the household appliances.In improved model predictive control(IMPC),the set of constraints for the powerflow in the system is optimized by the ANN,which is trained by EPO.Such a tuning based prediction model is presented in the IMPC technique.The proposed work is implemented in the MATLAB/Simulink platform.The energy management capability of the proposed system is analyzed for different atmospheric conditions.The total system cost,life cycle cost and annualized cost for IMPC are 48%,45%and 15%,respectively.From the performance analysis,the cost obtained by the proposed method is very low compared to that obtained by the existing techniques.

企鹅珍珠贝热休克蛋白70基因的克隆与序列比较分析

采用同源克隆和锚定PCR技术,从企鹅珍珠贝Pteria penguin中克隆到热休克蛋白hsp70基因的cDNA全序列。cDNA全长2 308 bp,3’非编码区域(UTR)为234 bp,5’UTR为118 bp,开放阅读框(ORF)为1 956 bp,编码651个氨基酸,分子量为70.97 kd,理论等电点为5.24,有2个糖基化位点:NKSI和NVSA,并含有HSP70家族的3个签名序列:IDLGTTYS,DLGGGTFD和IVLVGGSTRIPKIQK,以及C末端的保守序列EE-VD。结合BLAST分析的结果,可以确认获得的cDNA序列为企鹅珍珠贝HSP70的编码序列。与合浦珠母贝Pinctada fucata hsp70的氨基酸序列相比,企鹅珍珠贝多1个糖基化位点NVSA,少1个氨基酸,包括1个氨基酸插入和2个缺失。两者的氨基酸序列一致性高达92%,突变位点52个;两者的核苷酸序列一致性高达79%,突变位点416个。系统发育分析表明两者的亲缘关系最近,与传统分类相符,然后与太平洋牡蛎等聚合在一起。该基因的克隆和比较分析为进一步深入研究珍珠贝类的抗逆机理、抗性育种及其进化具有重要意义。

Ecological responses of typical Antarctic marine organisms to climate change and anthropogenic impacts

To improve our understanding and ability to predict biological responses to global climate change, it is important to be able to distinguish the influences of natural forcing from anthropogenic impacts. In the ice-free areas of Antarctica, lake and terrestrial sediments that contain penguin guanos, seal excrement and other biological remains provide natural archives of ecological, geological and climatic information that range from hundreds to thousands of years old. Our review focuses on the paleoecology of typical Antarctic marine organisms （penguins, seals and Antarctic krill） and their responses to climate change and human activities over centennial and millennial timescales. Land-based seabirds and marine mammals play an important role in linking the marine and terrestrial ecosystems and act as bio-vectors, transporting large amounts of nutrients and contaminants from ocean to land.

Analysis of phosphorus forms in sediment cores from ephemeral ponds on Ardley Island, West Antarctica

The guano of penguins, other seabirds, and pinnipeds is an important source of phosphorus in the ecosystems of Antarctica. To study the vertical distribution of phosphorus in sediments influenced by penguins, we measured phosphorus forms in two sediment cores （（31 and Q2） from ephemeral ponds on Ardley Island. We also investigated the correlations between these phosphorus forms and physicochemical characteristics. Inorganic phosphorus was the main form of phosphorus in both cores. The vertical distribution patterns of phosphorus forms in G1 and Q2 differed, indicating different sedimentary sources. The GI sediment profile was more influenced by penguin guano than the Q2 profile, and as a result sediments in the G1 core had higher total phosphorus, non-apatite inorganic phosphorus, and apatite phosphorus content. The findings from two ephemeral ponds on Ardley Island indicate that the contribution of penguin guano to organic matter in G1 core has increased in recent times, while Q2 showed a relatively larger contribution from mosses in ancient times, evident from the lithology and the vertical trend in organic matter.

Detection of Persistent Organochlorine Pollutants in Eggs of Antarctic Seabirds Based on Gas Chromatography and Their Ecological Environment Significance

By using internal standard method based on gas chromatography-electron capture detector （GC-ECD）, the contents of persistent or- ganochlorine pollutants polychorinated biphenyls （PCBs） and organochlorine pesticides （OCPs） in eggs of seabirds （ Catharacta Ionnbergi, Cathar- acta maccormicki, Pygoscelis papua and Macronectes giganteus） breeding on King George Island, Antarctica were detected, and their ecological environment significance was discussed. The results showed that the recovery of various compounds ranged from 68.6% to 90.8% ; relative stand- ard deviation （RSD） was 3.6%, and the lowest detection limits of PCBs and OCPs were 0.8 - 16 and 2 - 12 pg respectively, which could meet the demands for the residue analysis of trace persistent organochlorine pollutants in the eggs of Antarctic seabirds. The contents of PCBs, DDTs, HCB and HCHs in the eggs of Antarctic seabirds were 0.5 -515.5, 2.0 -304.4,0.5 -70.5, and 0.5 -2.0 ng/g respectively. In addition, the accumula- tion of PCBs and OCPs in the skuas was enhanced gradually through the food chain. The maximums of persistent organochlorine pollutants ap- peared in the eggs of C. Ionnbergi, followed by the eggs of C. maccomicki. The detection of OCPs and PCBs in the eggs of Antarctic seabirds was not interfered by other compounds containing chlorine, showing that the extraction, purification and detection method was suitable for the analysis of OCPs and PCBs in the eggs of Antarctic seabirds and has high sensitivity and reliability.

企鹅珍珠贝Dmrt2基因的克隆及表达分析

本研究利用RACE-PCR技术获得企鹅珍珠贝(Pteria penguin)一个Dmrt2基因cDNA的全长序列,通过荧光定量PCR分析Dmrt2基因在各组织中的表达特征,以及在早期卵巢、成熟期卵巢、早期精巢、成熟期精巢和排放期精巢中的表达变化。结果表明,Dmrt2基因全长1 257bp,其中开放阅读框(open reading frame,ORF)为951 bp,编码316个氨基酸,5′非编码区(untranslated region,UTR)为52 bp,3′UTR为254 bp,第20位到第73位氨基酸为DM结构域。预测其分子质量为36.61ku,等电点为9.80。氨基酸序列比对显示该企鹅珍珠贝Dmrt2基因与黑蝶真珠蛤(Pinctada margaritifera)和马氏珠母贝(Pinctada martensii)的Dmrt2基因同源性(identity)最高,分别为46.0%和45.7%。其中在DM结构域高度同源。荧光定量PCR分析组织表达特征显示,Dmrt2在企鹅珍珠贝的外套膜、鳃、消化盲囊、足、精巢和卵巢均有表达,其中在精巢中表达量最高(P<0.05),足为其次,在闭壳肌中没有检测到Dmrt2表达。对性腺发育不同时期的表达量分析发现,Dmrt2在发育早期和成熟期卵巢中表达量都很低,在发育早期精巢中表达量较高,在成熟期精巢检测到最大表达量(P<0.05),到精巢排放期表达显著下降,推测Dmrt2可能与企鹅珍珠贝精巢的发育有关,可能参与了企鹅珍珠贝雄性性别分化和性腺发育这一生理过程。

A 50-years record of dichloro-diphenyl-trichloroethanes and hexachloro-cyclohexanes in lake sediments and penguin droppings on King George Island, Maritime Antarctic

Since the ban on the use of organochlorine pesticides （OCPs） such as dichloro-diphenyl-trichloroethane （DDT） and hexachlorocyclohexane（HCH） in agriculture, their levels have generally dropped. In a number of cases, however, the levels of these OCPs were found to be unchanging or even increasing after the ban. With the aim to unveil the possible causes of these exceptions, we collected two lake cores from King George Island, West Antarctica, and determined their accumulation flux profiles and temporal trends of these OCPs. In the lake core sediments with glacier meltwater input, the accumulation flux of DDT shows an abnormal peak around 1980s in addition to the expected one in 1960s. In the lake core sediments without glacier meltwater input, the accumulation flux of DDT shows a gradual decline trend after the peak in 1960s. This striking difference in the DDT flux profiles between the two lake cores is most likely caused by the regional climate warming and the resulted discharge of the DDT stored in the Antarctic ice cap into the lakes in the Antarctic glacier frontier. Furthermore, to investigate the change of OCPs loadings in the Antarctic coastal ecosystem, we reconstructed the HCH and DDT concentration profiles in penguin droppings and observed a gradual increase for the former and a continuous decrease for the latter during the past 50 years. The increase of HCH seems to be due to the regional warming from the early 1970s and the resulted HCH discharge to the coastal ecosystem by glaciers＇ meltwater and the illegal use of HCH in the Southern Hemisphere in the recent decade. The different temporal trends of HCH and DDT accumulation rate in the lake core with glacier meltwater input and the aged penguin droppings can be explained by their different water-soluble property.

Stimulation of gaseous phosphine production from Antarctic seabird guanos and ornithogenic soils

Matrix-bound phosphine （MBP） is a general term used to indicate non-gaseous reduced phosphorus compounds that are transformed into phosphine gas upon reaction with bases or acids. Antarctic seabird guanos and ornithogenic soils were used as materials to compare the different digestion methods for transforming matrix-bound phosphine into phosphine gas. The results demonstrated that more phosphine gas in most of Antarctic environmental materials was formed of matrix-bound phosphine by caustic digestion than by acidic digestion. The comparative study on different digestion methods also revealed that the fraction of MBP converted to gaseous phosphine during the digestion depended on the temperature. The optimal digestion temperature was close to 70℃and the optimal digestion time was about 20 min. Acidic conditions were more favorable for the release of matrix-bound phosphine compared to the neutral conditions. A proper water dilution can increase the production and emission of phosphine from the Antarctic penguin guanos.

The sediments of lake on the Ardley Island, Antarctica: Identification of penguin-dropping soil

During CHINARE 15(Dec. 1998 Mar. 1999), a lake core 67.5 cm in length, was sampled in Y2 lake, which is located on the Ardley Island, Antarctica. The concentrations of some chemical elements in Y2 lake sediments were analyzed. According to comparative research on elementary characters of sediments in Antarctic West Lake, fresh penguin dropping as well as guano soil on the Ardley Island and Pacific Island in South China Sea, it presents that the Y2 lake sediments were ameliorated by penguin dropping. The result of element cluster analysis shows that the type elements in the sediment impacted by penguin dropping include Sr,F,S,P,Ca,Se,Cu,Zn and Ba. This can provide a base for further interpreting the climatic and environmental event recorded in the sediment.

Drag Reduction in a Swimming Humboldt Penguin, Spheniscus Humboldti, when the Boundary Layer is Turbulent

An area of protruding feathers found around the beak of many penguin species is thought to induce a turbulent boun~dary layer whilst swimming. Hydrodynamic tests on a model Humboldt penguin, Spheniscus humboldti, suggest that induced turbulence causes a significant reduction in boundary layer height, flow separation, and an average of 31 % reduction in drag (1.0 m/s to 4.5 m/s). Visualisation of surface flow showed it to follow the body profile, over the feet and tail, before separating. Movement of the feet in swimming penguins correlates with steering of the bird. Induced turbulence may therefore further increase swimming efficiency by reducing the amount of foot movement required to direct the swimming bird.

Preliminary investigation of mercury in bone tissues of skua and penguin in Antarctica using AFS and Synchrotron Radiation X-ray Fluorescence(SR-XRF)

Mercury （Hg） was investigated in bone tissues of skua （ Catharacta maccormick） and penguin （Pygoscelis adeliae） collected in the maritime Antarctic using atomic fluorescence spectrometry （AFS） and synchrotron radiation X-ray fluorescence （SR-XRF） method. The total levels of mercury in bone tissues of penguin and skua are much lower than those in other organs （e. g. , kidney, liver）. The toxic effects of mercury in bone tissues of seabirds in polar region are not known. We have used SR- XRF method to map the distribution of trace levels of mercury in bones. The levels of mercury are found to be enriched somewhere near the periosteal surface and/or endosteal surface. The distribution of mercury shows strongly correlation with that of some essential elements and probably poses negative effect on the bone metabolism inferring from the relationship of mercury with the other elements. These studies represent a first step toward understanding the toxic effects of mercury on bone of polar animals by suggesting the possible microscopic investigation.

Potential methane production rates and its carbon isotopic composition from ornithogenic tundra soils in coastal Antarctic

Methane （CH4） is one of important greenhouse gases with chemical activity. The determination of isotopic compositions for CH4 emitted from the soils helps us to understand its production mechanisms. CH4 isotope measurements have been conducted for different types of global terrestrial ecosystems. However, no isotopic data of CH4 have been reported from Antarctic tundra soils. In this paper, ornithogenic soil profiles were collected from four penguin colonies, and potential CH4 production rates and its 13C ratio （δ13C） were investigated based upon laboratory incubation experiments. The mean CH4 production rates are highly variable in these soil profiles, ranging from 0.7 to 20.3μg CH4-C kg-1·h-1. These omithogenic soils had high potential production rates of CH4 under ambient air incubation or under N2 incubation, indicating the importance of potential CH4 emissions from penguin colonies. Most of the soil samples had higher δ13C-CH4 under N2 incubation （-39.28%-43.53%） than under the ambient air incubation （-42.81%-57.19%）. Highly anaerobic conditions were conducive to the production of CI-h enriched in 13C, and acetic acid reduction under N2 incubation might be a predominant source for soil CH4 production. Overall the δ13C-CH4 showed a significant negative correlation with CH4 production rates in ornithogenic tundra soils under N2 incubation （R2=0.41,p〈0.01） or under the ambient air incubation （RE=0.50,p〈0.01）. Potential CH4 production from ornithogenic soils showed a significant positive correlation with total phosphorus （TP） and NH4＋-N contents, pH and soil moisture （Mc）, but the δ13C-CH4 showed a significant negative correlation with TP and NH4＋ -N contents, pH and Me, indicating that the deposition amount of penguin guano increased potential CH4 production rates from tundra soils, but decreased the δ13C-CH4. The CH4 emissions from the ornithogenic soils affect carbon isotopic compositions of atmospheric CH4 in coastal Antarctica.

Preliminary determination of calcium,phosphorus,and the calcium/phosphorus ratio in cortical bone of Chinstrap penguin using synchrotron X-ray fluorescence analysis

Synchrotron radiation X-ray fluorescence （SR-XRF） approach was applied to analyzing of Chinstrap penguin （ Pygoscelis Antarctica） cortical bone. The method enabled the in situ determination of Ca and P concentrations and the Ca/P ratio in cortical bone. The preliminary results show that ： （ 1 ） there is the bone site-related difference for Ca and P concentrations. The mean values for the investigated parameters （ on a dry-weight basis） are： 30.7% （Ca） and 14.9% （P） for the femoral cortical bone, 21.4% （Ca） and 11.5% （P） for wing cortical bone. （2） The variation for the Ca/P ratio in cortical bone is lower than those for Ca and P separately. This is in agreement with the previous report that the specificity of the Ca/P ratio is better than that of Ca and P concentrations and is more reliable for the diagnosis of bone disorders. The authors suggest that further studies be conducted to establish norreal values of Ca, P and Ca/P ratio for polar animals and provide a basis for the diagnosis of bone disorders.