Insights into the Holocene environmental setting of Terra Nova Bay region (Ross Sea, Antarctica) from oxygen isotope geochemistry of Adélie penguin eggshells

To identify the dietary composition and characteristics of both Adélie (Pygoscelis adeliae) and Emperor (Aptenodytes forsteri) penguins at four breeding sites, we performed stable carbon (δ13C) and nitrogen (δ15N) isotope analysis of down samples taken from penguin chicks. Adélie Penguin chicks at Cape Hallett mostly fed on Antarctic krill (Euphausia superba; 65.5 ± 3.5%), a reflection of the prevalence of that species near Cape Hallett, and no significant differences were noted between 2017 and 2018. However, Adélie Penguin chicks at Inexpressible Island, located near Terra Nova Bay, fed on both Antarctic silverfish (Pleuragramma antarctica; 42.5%) and ice krill (Euphausia crystallorophias; 47%), reflecting the high biomass observed in Terra Nova Bay. Meanwhile, no significant difference was noted between the two breeding sites of the Emperor Penguin. Emperor Penguin chicks predominantly fed on Antarctic silverfish (74.5 ± 2.1%) at both breeding sites (Cape Washington and Coulman Island), suggesting that diet preference represents the main factor influencing Emperor Penguin foraging. In contrast, the diet of the Adélie Penguin reflects presumed regional differences in prey prevalence, as inferred from available survey data.

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Ancient Adélie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica

Geology ◽

10.1130/g48230.1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Steven D. Emslie

Keyword(s):

Ross Sea ◽

Bone Collagen ◽

Adélie Penguin ◽

Pygoscelis Adeliae ◽

Adelie Penguin ◽

Terra Nova Bay ◽

Penguin Colony ◽

Marine Productivity ◽

First Time ◽

Adélie Penguins

The Ross Sea (Antarctica) is one of the most productive marine ecosystems in the Southern Ocean and supports nearly one million breeding pairs of Adélie penguins (Pygoscelis adeliae) annually. There also is a well-preserved record of abandoned penguin colonies that date from before the Last Glacial Maximum (>45,000 14C yr B.P.) through the Holocene. Cape Irizar is a rocky cape located just south of the Drygalski Ice Tongue on the Scott Coast. In January 2016, several abandoned Adélie penguin sites and abundant surface remains of penguin bones, feathers, and carcasses that appeared to be fresh were being exposed by melting snow and were sampled for radiocarbon analysis. The results indicate the “fresh” remains are actually ancient and that three periods of occupation by Adélie penguins are represented beginning ca. 5000 calibrated calendar (cal.) yr B.P., with the last occupation ending by ca. 800 cal. yr B.P. The presence of fresh-appearing remains on the surface that are actually ancient in age suggests that only recently has snowmelt exposed previously frozen carcasses and other remains for the first time in ~800 yr, allowing them to decay and appear fresh. Recent warming trends and historical satellite imagery (Landsat) showing decreasing snow cover on the cape since 2013 support this hypothesis. Increased δ13C values of penguin bone collagen further indicate a period of enhanced marine productivity during the penguin “optimum”, a warm period at 4000–2000 cal. yr B.P., perhaps related to an expansion of the Terra Nova Bay polynya with calving events of the Drygalski Ice Tongue.

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Particulate organic matter release below melting sea ice (Terra Nova Bay, Ross Sea, Antarctica): Possible relationships with zooplankton

Journal of Marine Systems ◽

10.1016/j.jmarsys.2021.103510 ◽

2021 ◽

pp. 103510

Author(s):

Alessandro Cau ◽

Claudia Ennas ◽

Davide Moccia ◽

Olga Mangoni ◽

Francesco Bolinesi ◽

...

Keyword(s):

Organic Matter ◽

Sea Ice ◽

Particulate Organic Matter ◽

Ross Sea ◽

Terra Nova Bay ◽

Terra Nova

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A comparison between polynya area and associated ice production with mooring-based measurements of temperature, salinity and currents in the southwestern Ross Sea, Antarctica

Annals of Glaciology ◽

10.3189/172756411795931705 ◽

2011 ◽

Vol 52 (57) ◽

pp. 291-300 ◽

Cited By ~ 3

Author(s):

Stefan Kern ◽

Stefano Aliani

Keyword(s):

Ross Sea ◽

Time Lag ◽

Ice Formation ◽

Terra Nova Bay ◽

In Situ Observations ◽

Satellite Microwave ◽

Terra Nova ◽

Ice Production ◽

The Impact

AbstractWintertime (April–September) area estimates of the Terra Nova Bay polynya (TNBP), Antarctica, based on satellite microwave radiometry are compared with in situ observations of water salinity, temperature and currents at a mooring in Terra Nova Bay in 1996 and 1997. In 1996, polynya area anomalies and associated anomalies in polynya ice production are significantly correlated with salinity anomalies at the mooring. Salinity anomalies lag area and/or ice production anomalies by about 3 days. Up to 50% of the variability in the salinity at the mooring position can be explained by area and/or ice production anomalies in the TNBP for April–September 1996. This value increases to about 70% when considering shorter periods like April–June or May–July, but reduces to 30% later, for example July–September, together with a slight increase in time lag. In 1997, correlations are smaller, less significant and occur at a different time lag. Analysis of ocean currents at the mooring suggests that in 1996 conditions were more favourable than in 1997 for observing the impact of descending plumes of salt-enriched water formed in the polynya during ice formation on the water masses at the mooring depth.

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Diesel oil and PCB-degrading psychrotrophic bacteria isolated from Antarctic seawaters (Terra Nova Bay, Ross Sea)

Polar Research ◽

10.3402/polar.v23i2.6275 ◽

2004 ◽

Vol 23 (2) ◽

pp. 141-146 ◽

Cited By ~ 9

Author(s):

Maria De Domenico ◽

Angelina Lo Giudice ◽

Luigi Michaud ◽

Marcello Saitta ◽

Vivia Bruni

Keyword(s):

Ross Sea ◽

Diesel Oil ◽

Psychrotrophic Bacteria ◽

Terra Nova Bay ◽

Terra Nova

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Summer Epiphytic Diatoms from Terra Nova Bay and Cape Evans (Ross Sea, Antarctica) - A Synthesis and Final Conclusions

PLoS ONE ◽

10.1371/journal.pone.0153254 ◽

2016 ◽

Vol 11 (4) ◽

pp. e0153254 ◽

Cited By ~ 15

Author(s):

Roksana Majewska ◽

Peter Convey ◽

Mario De Stefano

Keyword(s):

Ross Sea ◽

Epiphytic Diatoms ◽

Terra Nova Bay ◽

Terra Nova

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Significance of selected halocarbons monitoring in air samples collected in the Terra Nova Bay region (northern Victoria Land, Antarctica)

Antarctic Science ◽

10.1017/s0954102099000322 ◽

1999 ◽

Vol 11 (2) ◽

pp. 261-264 ◽

Cited By ~ 3

Author(s):

Filippo Mangani ◽

Michela Maione ◽

Luciano Lattanzi

Keyword(s):

Ross Sea ◽

Atmospheric Concentration ◽

Air Samples ◽

Terra Nova Bay ◽

Victoria Land ◽

Rate Of Increase ◽

Terra Nova ◽

Concentration Levels

CCl3F (or CFC-11) and CCl2F2 (or CFC-12) were determined in air samples collected, during subsequent summer Antarctic campaigns, in different sampling sites in the Ross Sea Region. The samples were analysed by GC-ECD after enrichment. Data obtained since 1988–89 were plotted to observe the trend of CFCs atmospheric concentration levels. A decrease in the rate of increase of CFC-12 concentration was observed, whilst the concentration of CFC-11 was actually seen to be decreasing.

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