As baleen whales recover from severe exploitation, they are probably subject to a wide variety of threats within the Antarctic marine ecosystem, including directed take. Here we review both the management and current status of Antarctic baleen whales and consider those threats likely to impact on them. Threats range from global problems - marine pollution and climate change - to localized issues including shipping, habitat disturbance, unregulated wildlife tourism and fishery activities. We identify the most pressing anthropogenic threats to baleen whales including scientific whaling and climate change. It is unclear whether current management approaches will be able to effectively encompass all these threats while also accounting both for the differing levels of scientific understanding and for the differing recovery rates of the whale species. For management we recommend the following: 1) incorporation of both ecosystem considerations and the suite of identified threats not limited to direct take, 2) identification of measurable indicators of changes in whales that allow more certainty in monitoring of populations and the environment, and 3) recognition of significant relationships between baleen whales and habitat features to provide information on distribution and use.

Archaea, once thought to be only extremophiles, are now known to be abundant in most environments. They can predominate in microbial communities and be significantly involved in many global biogeochemical cycles. However, Archaea have not been reported in Antarctic sea ice. Our understanding of the ecology of Antarctic sea ice prokaryotes is still in its infancy but this information is important if we are to understand their diversity, adaptations and biogeochemical roles in Antarctic systems. We detected Archaea in sea ice at two sampling sites taken from three subsequent years using conserved 16S rRNA gene archaeal primers and PCR. Archaeal abundance was measured using quantitative PCR and community diversity was investigated by sequencing cloned 16S rRNA gene PCR products. Archaea in Antarctic sea ice were found to be in low abundance consisting of ≤ 6.6% of the prokaryotic community. The majority, 90.8% of the sequences, clustered with the recently described phylum Thaumarchaeota, one group closely clustered with the ammonia-oxidizing Candidatus Nitrosopumilus maritimus. The remainder of the clones grouped with the Euryarchaeota.

Globally, areas categorically known to be free of human visitation are rare, but still exist in Antarctica. Such areas may be among the most pristine locations remaining on Earth and, therefore, be valuable as baselines for future comparisons with localities impacted by human activities, and as sites preserved for scientific research using increasingly sophisticated future technologies. Nevertheless, unvisited areas are becoming increasingly rare as the human footprint expands in Antarctica. Therefore, an understanding of historical and contemporary levels of visitation at locations across Antarctica is essential to a) estimate likely cumulative environmental impact, b) identify regions that may have been impacted by non-native species introductions, and c) inform the future designation of protected areas under the Antarctic Treaty System. Currently, records of Antarctic tourist visits exist, but little detailed information is readily available on the spatial and temporal distribution of national governmental programme activities in Antarctica. Here we describe methods to fulfil this need. Using information within field reports and archive and science databases pertaining to the activities of the United Kingdom as an illustration, we describe the history and trends in its operational footprint in the Antarctic Peninsula since c. 1944. Based on this illustration, we suggest that these methodologies could be applied productively more generally.

Deception Island, an active stratovolcano located in the South Shetland Islands, Antarctica, provides excellent conditions for the thermophilic bacteria growth because of high ground temperatures in specific areas, such as Fumarole Bay where the temperatures are above the mesophilic range. Denaturing Gradient Gel Electrophoresis (DGGE) was used with the 16S ribosomal gene to analyse cultures of thermophilic bacteria from a soil sample taken from Fumarole Bay. Nine bands were sequenced and analysed from DGGE and they indicated the presence of bacteria from the genera Geobacillus, Bacillus, Brevibacillus, Thermus and uncultured sulphate reducing bacteria. Some of which have been reported in other Antarctic geothermal sites. Geobacillus, Bacillus and Brevibacillus genera were successfully cultivated in an enriched medium. A pure culture of one thermophilic Geobacillus bacterium was obtained closely related to Geobacillus jurassicus.

The increase of tourism to the Antarctic continent may entail not only local but also global environmental impacts. These latter impacts, which are mainly caused by transport, have been generally ignored. As a result, there is a lack of data on the global impacts of Antarctic tourism in terms of energy consumption and carbon dioxide emissions. This paper presents and applies a methodology for quantifying CO2 emissions, both for the Antarctic vessel fleet as a whole and per passenger (both per trip and per day). The results indicate that the average tourist trip to Antarctica results in 5.44 t of CO2 emissions per passenger, or 0.49 t per passenger and day. Approximately 70% of these emissions are attributable to cruising and 30% to flying, which highlights the global environmental relevance of local transport for this type of tourism.

Southern elephant seals Mirounga leonina within the Kerguelen province disperse between Marion Island (MI), Iles Crozet (IC) and Iles Kerguelen (IK) despite the high site fidelity characteristic of this species. From 1987–2002, 199 IC individuals, or 11.63% of the tagged population there, were resighted at MI. Resights of IC seals at MI peaked during the juvenile moult and seals aged 0–2 represent 66% of all resights made. Equal numbers of male and female seals (all age classes) were dispersing. Dispersing breeding females (n = 22, on 33 occasions) outnumbered dispersing breeding males (n = 6, on 16 occasions), after initially emigrating from IC to MI as juvenile seals (natal dispersal). Greater male-mediated gene flow was ultimately attained due to the polygynous mating system and some extremely successful males. Of 132 seals fitted with satellite-relay data loggers at MI, six hauled out at IC and three at IK. Two of the seals which migrated to IC were born at MI; all others were unmarked males likely to be native to IC or IK. Dispersal should ideally be considered when assessing vital rates for southern Indian Ocean elephant seal populations.

Alkanes and polycyclic aromatic hydrocarbons were quantified in samples of coastal sediments along Fildes Peninsula, King George Island, South Shetland Islands, Antarctica, during the summers of 2005 and 2007. Quantification was done by using GC-MS and applying the EPA 3550B method. Individual polycyclic aromatic hydrocarbon (PAHs) concentrations were below 14.4 ng g-1 dry wt in 2005 and below 88.7 ng g-1 dry wt in 2007. Alkanes concentrations were higher than those of PAHs and ranged from 8 to 2236 ng g-1 dry wt in 2005 and from 53 to 745 ng g-1 dry wt in 2007. Results of total PAHs and alkanes were integrated along with base administrative and geographic maps in a GIS environment to determine the geographic extent of hydrocarbons detected. The largest concentrations were found in areas near research stations where total n-alkanes suggest petrogenic sources and where some diagnostic ratios suggest the presence of some PAHs produced by pyrogenic processes. Even if concentrations of hydrocarbons are low, they seem to be a result of increases in scientific activities, in the activities of the stable population, in the number of tourists, or a combination of theses factors.

The interannual variability of net community production (NCP) and air-sea CO2 flux in a naturally iron fertilized and productive area of the Southern Ocean (Kerguelen plateau) was investigated using a 1D biogeochemical model driven by satellite chlorophyll, sea surface temperature and wind speed data for the 1997–2007 period. The model simulates the low fCO2 and dissolved inorganic carbon (DIC) measured during summers 2004–05, 2005–06, 2006–07 and the high NCP derived from a seasonal carbon budget in the surface waters of these blooms. Although satellite data show high interannual variability in the dynamics and magnitude of the bloom during the 1997–2007 decade, the simulated interannual variability of the NCP was only ± 14%. This unexpected result could be due to the combined effect of both the duration and the start date of the bloom, the latter determining the depth of the mixed layer used to compute the NCP. In the productive area, the interannual variability of air-sea CO2 flux (± 13%) was not only driven by the biological effect but also by the solubility effect. Our results contrast with previous studies in the high nutrient, low chlorophyll regions of the Southern Ocean.

Following a report of supposed fragments of calcareous dinoflagellate cysts from a Pleistocene drill core (CRP-1) recovered in the Ross Sea, Antarctica, sediments of the same core were re-investigated for their microfossil content. Besides common foraminifera and other microfossils, rare complete cysts of calcareous dinoflagellates were found. All cysts belong to the species Caracomia arctica (Gilbert & Clark, 1983) Streng, Hildebrand-Habel & Willems, 2002, a taxon characteristic of late Neogene high latitude, coldwater environments. Two morphotypes can be distinguished, C. arctica f. arctica and C. arctica f. rossensis, of which the latter is described as a new form. The presence of C. arctica strengthens diatom-based palaeoenvironmental reconstructions of periodical sea ice-free conditions at the time of deposition. Accordingly, cysts of C. arctica are interpreted as resting cysts that allow survival during harsh intervals of the high latitude environment. Previously reported calcareous dinoflagellates cyst fragments from these sediments are re-interpreted as test fragments of bilamellar foraminifera, which represent the most common group of foraminifers in the sediments.

Although predictions suggest that ocean acidification will significantly impact polar oceans within 20–30 years, there is limited information regarding present-day pH dynamics of the Southern Ocean. Here, we present novel high-frequency observations of pH collected during spring of 2010 using SeaFET pH sensors at three locations under fast sea ice in the southern Ross Sea. During these deployments in McMurdo Sound, baseline pH ranged between 8.019–8.045, with low to moderate overall variation (0.043–0.114 units) on the scale of hours to days. The variation was predominantly in the direction of increased pH relative to baseline observations. Estimates of aragonite saturation state (ΩAr) were > 1 with no observations of subsaturation. Time series records such as these are significant to the Antarctic science community; this information can be leveraged towards framing more environmentally relevant laboratory experiments aimed at assessing the vulnerability of Antarctic species to ocean acidification. In addition, increased spatial and temporal coverage of pH datasets may reveal ecologically significant patterns. Specifically, whether such variation in natural ocean pH dynamics may drive local adaptation to pH variation or provide refugia for populations of marine calcifiers in a future, acidifying ocean.

Rapid climate warming has been observed in the region of the Antarctic Peninsula since the middle of the last century with the largest warming rate in the winter. Decadal variability of winter temperature on the regional scale was analysed using eight station datasets of the Antarctic Peninsula region. The Scientific Committee on Antarctic Research Reference Antarctic Data for Environmental Research from the period 1950–2009 were used. Fourier and wavelet transforms of the averaged temperature anomaly time series reveal a clear separation between the oscillations with three to eight year periods and a decadal oscillation with a period of around 16 years. On the Antarctic Peninsula region scale, 16 year periodicity in the winter temperature variability has not been described before. Both spectral components show similar spectral power and statistical significance (5–10%). This is evidence of their comparable importance for winter temperature changes in the Antarctic Peninsula region. The three to eight year periods are most probably related to the El Niño–Southern Oscillation and Antarctic Circumpolar Wave signals, but the 16 year oscillation has not been identified within the scope of this analysis. The possible effect of the decadal oscillation in the winter temperature trend estimate is discussed.

Bromoform concentrations in water of the slush layer that developed at the interface between snow and sea ice were measured during the seasonal warming in Lützow-Holm Bay, East Antarctica. Mean bromoform concentration was 5.5 ± 2.4 pmol l-1, which was lower than that of the under-ice water (10.9 ± 3.5 pmol l-1). Temporal decrease in bromoform concentrations and salinity with increasing temperature of the slush water suggest that the bromoform concentrations were reduced through dilution with meltwater input from the upper surface of sea ice. In contrast, bromoform concentrations in the under-ice water increased during this period while the salinity of the under-ice water decreased. It is speculated that the sea ice meltwater input contained high bromoform concentrations from the brine channels within the sea ice and from the bottom of the ice that were contributed to the increased bromoform concentrations in the under-ice water.