Feeding selectivity in Notothenia neglecta, Nybelin, from Potter Cove, South Shetland Islands, Antarctica

A study of feeding selectivity in Notothenia neglecta Nybelin 1951, was carried out between October 1988 and January 1989 at Potter Cove, King George Island, where this is the dominant fish species. The abundance and biomass of benthic organisms from 0–40m were compared with their occurrence in the diet of 142 fish. The Ivlev index indicated that the food items positively selected by the fish were sedentary polychaetes, the isopod Glyptonotus antarcticus, the gammarid amphipod Paradexamine sp., the bivalve Dacrydyum sp., the gastropods Margarella antarctica and Eatoniella sp., and algae. The biomass of the benthic community in the sampling area was low, presumably due to the effects of anchor ice. Despite being pelagic, krill (Euphausia superba) was by far the main food of N. neglecta which is considered a benthic feeder.

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H2O2 accumulation from photochemical production and atmospheric wet deposition in Antarctic coastal and off-shore waters of Potter Cove, King George Island, South Shetland Islands

Antarctic Science ◽

10.1017/s095410209900019x ◽

1999 ◽

Vol 11 (2) ◽

pp. 131-139 ◽

Cited By ~ 28

Author(s):

Doris Abele ◽

Gustavo A. Ferreyra ◽

Irene Schloss

Keyword(s):

Hydrogen Peroxide ◽

Surface Waters ◽

Wet Deposition ◽

High Energy ◽

South Shetland Islands ◽

King George Island ◽

The South ◽

Potter Cove ◽

Shetland Islands ◽

Snowfall Event

Temporal and spatial variations of the hydrogen peroxide accumulation were measured in off-shore waters and in intertidal rockpools near Jubany Station, King George Island, South Shetland Islands. As H2O2 photoformation is mainly driven by the short wavelength radiation in the UV-B and the UV-A range of the solar spectrum, the study was conducted between the beginning of October and the end of December 1995, the period of Antarctic spring ozone depletion. Wet deposition of H2O2 containing snow was identified as a major source of hydrogen peroxide in the surface waters of Potter Cove. As the concentrations of dissolved organic carbon (DOC) in Potter Cove surface waters were low (121 ± 59 μmol Cl−1), when compared to the highly eutrophicated waters on the German Wadden coast (6000–7000 μmol Cl−1), direct UV-induced DOC photo-oxidation was of only limited significance in the Antarctic sampling site. Nonetheless, under experimental conditions, H2O2 photoformation in Potter Cove surface waters amounted to 90 ± 40 nmol H2O2 h−1 l−1 under a UV-transparent quartz plate. When high energy UV-B photons were cut-off by a WG320 filter formation continued at a rate of 66 ± 29 nmol H2O2 h−1 l−1 due to UV-A and visible light photons. Samples from freshly deposited snow contained between 10 000 and 13 600 nmol H2O2 l−1, and a snowfall event in mid November resulted in a maximum concentration of 1450 nmol H2O2 l−1 in the upper 10 cm layer of Potter Cove surface waters. Maximal H2O2 concentrations in intertidal rockpools were even higher and reached up to 2000 nmol H2O2 l−1 after the snowfall event. During a grid survey on December 17 1995, H2O2 concentrations and salinity displayed a north to south gradient, with higher concentrations and PSU at the south coast of the cove. The reasons for this spatial inhomogenety are as yet unknown, but may relate to a minor local input of photo-reactive organic matter from creeks entering the cove in the south-east, as well as to waste water discharge from the station, located on the south beach.

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Pygoscelis penguin diets on King George Island, South Shetland Islands, with a special focus on the krill Euphausia superba

Antarctic Science ◽

10.1017/s0954102019000543 ◽

2020 ◽

Vol 32 (1) ◽

pp. 21-28 ◽

Cited By ~ 1

Author(s):

Anna Panasiuk ◽

Justyna Wawrzynek-Borejko ◽

Aleksandra Musiał ◽

Małgorzata Korczak-Abshire

Keyword(s):

Euphausia Superba ◽

South Shetland Islands ◽

Special Focus ◽

King George Island ◽

Pygoscelis Adeliae ◽

Human Pressure ◽

Shetland Islands ◽

Pygoscelis Antarcticus ◽

South Shetlands ◽

The Antarctic

AbstractIn the krill-based ecosystem of the Antarctic, fluctuations in the distribution and abundance of Euphausia superba may have strong impacts on predator populations; thus, it is crucial to observe the feeding ecology of Antarctic predators, especially in the light of climate change and increasing human pressure. We determined the composition of euphausiid species in diet samples collected from Adélie (Pygoscelis adeliae), chinstrap (Pygoscelis antarcticus) and gentoo (Pygoscelis papua) penguins on King George Island (South Shetlands Islands) during a breeding season. For all three penguin species, euphausiids (mainly E. superba) represented almost the entirety of researched stomach samples (i.e. 99.9% in the case of Adélie and chinstrap penguins), while gentoo penguins also proved to feed on fish (99.4% krill; 0.5% fish). Analysed material differed in the size of eaten E. superba specimens, with the smallest crustaceans consumed by Adélie penguins. Furthermore, we found differences in the ratio of consumed krill and krill size. Such disparities may be a result of sex-based differences and slight differences in feeding areas between the birds. Additionally, we noted some fragments of plastic debris in the investigated penguin diet samples.

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Recent retreat of ice cliffs, King George Island, South Shetland Islands, Antarctic Peninsula

Annals of Glaciology ◽

10.3189/1998aog27-1-633-635 ◽

1998 ◽

Vol 27 ◽

pp. 633-635 ◽

Cited By ~ 35

Author(s):

Byong-Kwon Park ◽

Soon-Keun Chang ◽

Ho Il Yoon ◽

Hosung Chung

Keyword(s):

Antarctic Peninsula ◽

South Shetland Islands ◽

King George Island ◽

Regional Warming ◽

Potter Cove ◽

Aerial Photos ◽

Shetland Islands ◽

Topographic Survey ◽

Water Depths ◽

Maxwell Bay

Comparison of aerial photos shows that the ice cliff in Marian Cove, Maxwell Bay, southwestern King George Island, retreated approximately 250 m between 1956 and 1986, but advanced about 40 m between December 1986 and January 1989. The advance in the late 1980s seems to be related to the cold austral winters of 1986-88. A topographic survey in January 1994 revealed that the ice cliff in Marian Cove had again retreated around 270 m since January 1989; approximately the same as from December 1956 to December 1986. in Potter Cove, the ice cliff retreated approximately 400 m from 1956-89. The more pronounced retreat here may be attributable to shallower water depths (<30m). These ice cliffs retreats are discussed as a possible consequence of recent regional warming.

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Age estimation for juvenile Notothenia rossii from Potter Cove, South Shetland Islands

Antarctic Science ◽

10.1017/s095410209200021x ◽

1992 ◽

Vol 4 (2) ◽

pp. 131-136 ◽

Cited By ~ 10

Author(s):

E. R. Barrera-Oro ◽

R. J. Casaux

Keyword(s):

Cross Sections ◽

Age Estimation ◽

Age Distribution ◽

South Shetland Islands ◽

Birth Date ◽

Age Group ◽

King George Island ◽

Potter Cove ◽

Shetland Islands ◽

Notothenia Rossii

Scales and whole otoliths were used for age estimation of juvenile Notothenia rossii specimens collected at Potter Cove, King George Island, South Shetland Islands, between 1983 and 1988. Results from the analysis of both types of material showed 96.7% agreement. Likewise, the examination of otolith cross sections of chosen specimens confirmed in all the cases the age readings obtained from the second whole sagittal otolith. Although the commonly accepted 1 July was used as the birth date of the fish for age calculations, data indicate that 1 October is closer to the biological birth date, since this species hatches in Spring. The length-age range of the fish was 18–44 cm and 3–7 years respectively, which fits well with the known length-age distribution of juvenile specimens of the species in the fjord. A comparison between observed and back-calculated mean length of age group 3 (24.6 and 25 cm respectively) indicated that not only the larger fish but the full size range of this age group was represented in our samples. Mean length data at age presented here are similar to the ones reported for fish from Admiralty Bay, King George Island, but differ from those of fish caught off Elephant Island. The use of whole otoliths for age estimation of juvenile N. rossii proved to be a reliable method with a precision of one year but, this might not be an appropriate technique for adult specimens.

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Components of the energy balance of the ground surface and their effect on the thermics of the substrata of the vegetation oasis at Henryk Arctowski Station, King George Island, South Shetland Islands

Polar Record ◽

10.1017/s003224740001593x ◽

2000 ◽

Vol 36 (196) ◽

pp. 3-18 ◽

Cited By ~ 1

Author(s):

P. Prosek ◽

M. Janouch ◽

K. Láska

Keyword(s):

Heat Flux ◽

Energy Balance ◽

Soil Temperature ◽

Sensible Heat Flux ◽

Ground Surface ◽

South Shetland Islands ◽

Radiation Balance ◽

Sensible Heat ◽

King George Island ◽

Shetland Islands

AbstractThis article presents the results of measurements of the components of ground-surface energy balance (radiation balance, sensible heat flux, latent heat flux, and ground heat flux) taken during the 1994/95 summer season at Poland's Henryk Arctowski Station, King George Island, South Shetland Islands (62°09'42”S, 58°28'10”W). This was the first time that these complex measurements had been taken in the central part of the South Shetlands archipelago. The results are evaluated at the level of daily and seasonal fluctuations. The consequences of energy balance on the temperature conditions of the soil substrata are highlighted. The verification of the degree of influence of a subset of energy-balance components on soil temperature allowed analysis of the relationships among soil temperature, radiation balance, and sensible heat flux. This analysis leads to the conclusion that there is a rapid reaction of the soil temperature to the radiation balance and sensible heat flux to a depth of 5 cm. The boundary atmosphere and soil substrate represent the basic components of the ecotops of the Antarctic vegetation oasis, so these results are interpreted in pedological or botanical studies in the search for environmental influences on the vegetation.

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A new Antarctic foraminiferal species for detecting climate change in sub-Recent glacier-proximal sediments

Antarctic Science ◽

10.1017/s0954102009990150 ◽

2009 ◽

Vol 21 (5) ◽

pp. 439-448 ◽

Cited By ~ 10

Author(s):

Wojciech Majewski ◽

Andrzej Tatur

Keyword(s):

Climate Change ◽

Climate Warming ◽

The Arctic ◽

South Shetland Islands ◽

King George Island ◽

Tidewater Glaciers ◽

Admiralty Bay ◽

Shetland Islands ◽

Foraminiferal Species ◽

Water Depths

AbstractCribroelphidium webbi sp. nov. is the only adequately described sub-Recent elphidiid foraminifer from Antarctica. In Admiralty Bay (King George Island, South Shetland Islands), it is found at several locations within inner fiord setting at water depths between 33 and 165 m, but most commonly shallower than 100 m. In outer basins this foraminifer is absent. In the cores analysed, C. webbi sp. nov. is present in well-constrained sub-Recent horizons that are clearly related to climate warming and deglaciation. These horizons represent a diachronous facies marker rather than a single stratigraphic layer. Cribroelphidium webbi sp. nov. shows clear association with retreating tidewater glaciers, therefore it is an important sensitive glacier-proximal indicator. It appears that it shares similar ecologic affinities with Cribroelphidium excavatum clavatum, which is widely distributed throughout the Arctic.

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Periphyton diversity in two different Antarctic lakes assessed using metabarcoding

Antarctic Science ◽

10.1017/s0954102021000316 ◽

2021 ◽

pp. 1-9

Author(s):

Paulo E.A.S. Câmara ◽

Láuren M.D. De Souza ◽

Otávio Henrique Bezerra Pinto ◽

Peter Convey ◽

Eduardo T. Amorim ◽

...

Keyword(s):

Dna Sequences ◽

High Throughput Sequencing ◽

Shannon Index ◽

South Shetland Islands ◽

King George Island ◽

Deception Island ◽

Maritime Antarctic ◽

Shetland Islands ◽

Antarctic Lakes ◽

Significant Difference

Abstract Antarctic lakes have generally simple periphyton communities when compared with those of lower latitudes. To date, assessment of microbial diversity in Antarctica has relied heavily on traditional direct observation and cultivation methods. In this study, sterilized cotton baits were left submerged for two years in two lakes on King George Island and Deception Island, South Shetland Islands (Maritime Antarctic), followed by assessment of diversity by metabarcoding using high-throughput sequencing. DNA sequences of 44 taxa belonging to four kingdoms and seven phyla were found. Thirty-six taxa were detected in Hennequin Lake on King George Island and 20 taxa were detected in Soto Lake on Deception Island. However, no significant difference in species composition was detected between the two assemblages (Shannon index). Our data suggest that metabarcoding provides a suitable method for the assessment of periphyton biodiversity in oligotrophic Antarctic lakes.

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