The McMurdo Dry Valleys are among the driest, coldest environments on Earth and are excellent analogues for the Martian northern plains. In preparation for the 2008 Phoenix Mars mission, we conducted an interdisciplinary investigation comparing the biological, mineralogical, chemical, and physical properties of wetter lower Taylor Valley (TV) soils to colder, drier University Valley (UV) soils. Our analyses were performed for each horizon from the surface to the ice table. In TV, clay-sized particle distribution and less abundant soluble salts both suggested vertical and possible horizontal transport by water, and microbial biomass was higher. Alteration of mica to short-order phyllosilicates suggested aqueous weathering. In UV, salts, clay-sized materials, and biomass were more abundant near the surface, suggesting minimal downward translocation by water. The presence of microorganisms in each horizon was established for the first time in an ultraxerous zone. Higher biomass numbers were seen near the surface and ice table, perhaps representing locally more clement environments. Currently, water activity is too low to support metabolism at the Phoenix site, but obliquity changes may produce higher temperatures and sufficient water activity to permit microbial growth, if the populations could survive long dormancy periods (∼106 years).

The geochemistry and vertical stratification of shallow meltwater ponds at 78°S near Bratina Island (McMurdo Ice Shelf) have been determined for late winter (October) and summer (January) conditions as part of the Latitudinal Gradient Project. Of the five frozen ponds investigated in October, all were stratified with respect to conductivity, and three had highly saline basal brines beneath the ice at temperatures of −16 to −20°C. In the ice column, inclusions of saline fluid were observed in channels between ice crystals; the abundance increasing with depth and decreasing ice crystal size. In January, seven of the ten ponds investigated (including ponds sampled in October) retained conductivity stratification, whereas significant thermal stratification was observed in only three ponds (maximum ΔT = 5.5°C). Basal brines, ice and meltwaters were Na-Cl or Na-SO4 dominated. FREZCHEM52 modelling, supported by changes in ion ratios, indicated that the precipitation of mirabilite (Na2SO4.10H2O) and gypsum (CaSO4.2H2O) during progressive freezing is an important determinant in chemical evolution of the basal brine. High pH (8.8–11.2) and over-saturation with respect to dissolved oxygen (> 20 mg L−1) in summer, and the presence of sulphide ions in basal brines in winter, occurred in those ponds which experienced high biological productivity during the summer months.

The coast of Victoria Land extends from Williamson Head (69°11'S, 158°E) to McMurdo Sound (77°S, 163°E). A comparison of various documents and images spanning several decades has allowed the ice front fluctuation and the iceberg calving flux during this century to be estimated. During the periods from 1956–65 to 1972–73 the floating glaciers underwent a reduction of 978 km2 with an iceberg calving flux of about 134 km2 yr−1. After this, during the periods from 1972–73 to 1989–91, the floating glaciers underwent an advance of 272 km2 with an iceberg calving flux of about 53 km2 yr−1. Glacier tongues with bottom accretion calve less often than those with bottom melting. Most floating glaciers have shown cyclic behaviour without a strong trend. Exceptions to this general style are Hells Gate ice shelf, McMurdo Ice Shelf and floating glaciers of Cape Adare which have undergone a significant retreat since the beginning of the 20th century. The different behaviour of these floating glaciers has been hypothesized as being due to: increased energy available for meltwater production of marine ice that progressively warmed these thin ice shelves and then increased iceberg calving (Hells Gate and McMurdo), or to increased melting at the ice-ocean interface related to a major intrusion of Circumpolar Deep Water from the nearby continental slope (Cape Adare). An estimate of the mass balance of East Antarctica from which these glaciers are fed shows a positive value, that is significant despite all the uncertainties of balance measurements.

Here we describe the evolution through winter of a layer of in situ supercooled water beneath the sea ice at a site close to the McMurdo Ice Shelf. From early winter (May), the temperature of the upper water column was below its surface freezing point, implying contact with an ice shelf at depth. By late winter the supercooled layer was c. 40 m deep with a maximum supercooling of c. 25 mK located 1–2 m below the sea ice-water interface. Transitory in situ supercooling events were also observed, one lasting c. 17 hours and reaching a depth of 70 m. In spite of these very low temperatures the isotopic composition of the water was relatively heavy, suggesting little glacial melt. Further, the water's temperature-salinity signature indicates contributions to water mass properties from High Salinity Shelf Water produced in areas of high sea ice production to the north of McMurdo Sound. Our measurements imply the existence of a heat sink beneath the supercooled layer that extracts heat from the ocean to thicken and cool this layer and contributes to the thickness of the sea ice cover. This sink is linked to the circulation pattern of the McMurdo Sound.

In February 1989, the partial skeleton of an ornithopod dinosaur was discovered during a British Antarctic Survey (BAS) expedition, supported by RRS John Biscoe, to the James Ross Island area, east of the Antarctic Peninsula. This was only the second dinosaur to be found in the continent of Antarctica, the first being an ankylosaur collected three years earlier (Olivero et al. 1986, Gasparini et al. 1987, Gasparini 1988, Gasparini & Olivero 1989, Olivero et al. 1991).

A new topographic database for King George Island, one of the most visited areas in Antarctica, is presented. Data from differential GPS surveys, gained during the summers 1997/98 and 1999/2000, were combined with up to date coastlines from a SPOT satellite image mosaic, and topographic information from maps as well as from the Antarctic Digital Database. A digital terrain model (DTM) was generated using ARC/INFO GIS. From contour lines derived from the DTM and the satellite image mosaic a satellite image map was assembled. Extensive information on data accuracy, the database as well as on the criteria applied to select place names is given in the multilingual map. A lack of accurate topographic information in the eastern part of the island was identified. It was concluded that additional topographic surveying or radar interferometry should be conducted to improve the data quality in this area. In three case studies, the potential applications of the improved topographic database are demonstrated. The first two examples comprise the verification of glacier velocities and the study of glacier retreat from the various input data-sets as well as the use of the DTM for climatological modelling. The last case study focuses on the use of the new digital database as a basic GIS (Geographic Information System) layer for environmental monitoring and management on King George Island.

Surface and subsurface sediments from a helipad in Bunger Hills were collected ten years after accidental contamination with a small quantity (probably < 10 litres) of petroleum products. The contaminants are dominated by Jet A2 synthetic lubricating oil which exhibits no evidence of degradation or environmental mobility. In contrast, Jet A1 turbine kerosene is less abundant at the surface than at 20 cm depth. There is no evidence for biodegradation of the Jet A1 in the subsurface sample, suggesting that kerosene is environmentally mobile in the surface sediments.

Flood-carved landforms across the deglaciated terrain of Victoria Land, East Antarctica, provide convincing geomorphological evidence for the existence of subglacial drainage networks beneath the Antarctic ice sheet, and motivate research into the inaccessible environment beneath the contemporary ice sheet. Through this research, our understanding of Antarctic subglacial hydrology is steadily building, and this paper presents an overview of the current state of knowledge. The conceptualization of subglacial hydrological behaviour was developed at temperate and Arctic glaciers, and is thus less mature in the Antarctic. Geophysical and remote sensing observations have demonstrated that many subglacial lakes form part of a highly dynamic network of subglacial drainage beneath the Antarctic ice sheet. Recent research into subglacial water flows, other than those directly concerned with lakes, has discovered potentially significant impacts on ice stream dynamics, ice sheet mass balance, and supplies of water to the ocean potentially affecting circulation and nutrient productivity. Despite considerable advances in understanding there remain a number of grand challenges that must be overcome in order to improve our knowledge of these subglacial hydrological processes.

We provide our perspective on the species-level taxonomy of notothenioid fishes, the dominant component of the fish fauna of Antarctica. There are 140 species in 45 genera, an increase of 15% since the previous summary in 2000. Biogeographically, 30 species are non-Antarctic, 33 are sub-Antarctic and 77 are Antarctic. The checklist is documented with footnotes that provide the rationale for our decisions. Supplementary Material provides additional details for our decisions on two species of Pogonophryne.

The Scotia Arc, linking the Magellan region with the Antarctic Peninsula, comprises young and old islands both near continents and isolated, and is the only semi-continuous link between cool temperate and Antarctic environments. It is an ideal region for studies on how marine biodiversity changes across an extended transition zone. Echinoids (sea urchins) and their associated epibionts were found across depths from 91–1045 m, with 19 species from shelf and four from slope depths. The 23 species from 38 trawls represent 31% of all echinoid species known from the Southern Ocean and 38% of the shelf/upper slope echinoids. The specimens collected comprise representatives of the five families Cidaridae, Echinidae, Temnopleuridae, Schizasteridae and Pourtalesiidae. Echinoids are probably a good model for how well we know Antarctic shelf and slope megabenthos; none of the species we report are new to science but we found nine (39%) of our study species present at new localities, some thousands of kilometres from previous findings. New biogeographic ranges are illustrated for Ctenocidaris gigantea, C. nutrix, C. spinosa, Abatus curvidens, A. ingens, A. shackletoni, Amphineustes rostratus, Tripylaster philippi and Pourtalesia aurorae. Southern Ocean echinoids show eurybathy as the mean depth range of our study species was 1241 m and only one was at less than 500 m. The current view of echinoid dominance of super-abundance in the shallows seems to be not transferable to shelf and slope depths as only one of 38 trawls was dominated by echinoids. Current knowledge on maximum sizes in Antarctic echinoids seems to be good as our morphometric measurements were mainly within known size ranges. Regular echinoids increased predictably in mass with increasing test length, apart from Ctenocidaris spinosa. Tissue mass of cidaroid species was ~17%, but across irregular species varied from 17.7–8.9%. No epibionts were found on irregular echinoids or Echinidae but 70 cidaroids examined carried 51 species representing ten classes. Many of these species are reported as cidaroid epibionts for the first time. Cidaroids and their epibionts constituted > 38% of the total macrofaunal richness in the trawls they were present in. Echinoids and their epibionts clearly contribute significantly to Southern Ocean biodiversity but are minor components of biomass except in the shallows.

A terrestrial sequence on Livingston Island, South Shetland Islands, known as the Williams Point Beds contains a well-preserved, diverse fossil flora previously assigned a Triassic age. Because of their supposed age, volcanic provenance and evidence for active volcanism, the Williams Point Beds have occupied a unique position in Gondwana (pre-Jurassic) stratigraphy in the Antarctic Peninsula region. However, a large new collection of plant specimens obtained at Williams Point has yielded several species of angiosperm leaves, which are abundant and occur at all levels within the Williams Point Beds sequence. Thus, a Triassic age is no longer tenable. On the basis of the plants present and published radiometric ages for associated strata, the Williams Point Beds fossil flora is reassigned to the Cretaceous, and there is some evidence for a more restricted Albian–Cenomanian age. This revision of the age of the Williams Point Beds removes all direct evidence for an active Triassic volcanic arc in the Antarctic Peninsula region.

It is recognized that birds become disorientated at night in the presence of artificial light (Bruderer et al. 1999). Bird strikes on vessels operating in the southern oceans have long been known (Ryan 1991), but few data have been published concerning these events. In the Southern Ocean the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) stipulates that, during fishing operations, deck lighting should be kept to a minimum and be directed inboard and downward (CCAMLR 2003, measures 25-02 and 25-03). However, these measures are designed to keep birds away from fishing gear rather than prevent bird strikes. The problem of bird strikes has been recognized by several territories within the southern oceans and policies to reduce the risk of them occurring are included in several management plans (Ryan & Glass 2001, policy 5.14 and Meere 2002, section 28:1f–1g). These do not, however, address the issue of ice-lights (powerful searchlights used to discern floating ice that might go undetected by radar), which are regarded as essential navigational aids.

Twenty two samples collected from the Tertiary La Meseta Formation of Cape Wiman, Seymour Island, Antarctic Peninsula yielded abundant and moderately diverse assemblages of marine palynoflora, dominated by dinoflagellate cysts, together with acritarchs and chlorophyta. The assemblages can be divided into three association: Association 1, characterized by low diversity dinoflagellate assemblage of late Early Eocene age which are dominated by Enigmadinium cylindrifloriferum; Association 2 characterized by more diverse dinoflagellate cyst assemblages, which show a marked decrease in the dominance of E. cylindrifloriferum, and an increase in relative abundance of Areosphaeridium cf. diktyoplokus; and Association 3 which is characterized by a decrease in dinoflagellate cyst diversity up section. Changes in dinoflagellate cyst dominance and diversity throughout the section suggests a gradation from a stressed, shallow marine palaeoenvironment to a more open near-shore, shallow marine system becoming progressively more nearshore up section. The assemblages are no older than late Early Eocene in age, and possibly as young as Mid–Late Eocene.

The diversity of lichens, especially crustose species, in continental Antarctica is still poorly known. To overcome difficulties with the morphology based species delimitations in these groups, we employed molecular data (nuclear ITS and mitochondrial SSU rDNA sequences) to test species boundaries within the genus Lecidea. Sampling was done along a north–south transect at five different areas in the Ross Sea region (Cape Hallett, Botany Bay to Mount Suess, Taylor Valley, Darwin Area and Mount Kyffin). A total of 153 specimens were collected from 13 localities. Phylogenetic analyses also include specimens from other regions in Antarctica and non-Antarctic areas. Maximum parsimony, maximum likelihood and Bayesian analyses agreed in placing the samples from continental Antarctica into four major groups. Based on this phylogenetic estimate, we restudied the micromorphology and secondary chemistry of these four clades to evaluate the use of these characters as phylogenetic discriminators. These clades are identified as the following species Lecidea cancriformis, L. andersonii as well as the new species L. polypycnidophora Ruprecht & Türk sp. nov. and another previously unnamed clade of uncertain status, referred to as Lecidea sp. (L. UCR1).

From 15 December 1992–4 January 1993 aerial surveys of ice seals were undertaken by Puma helicopter across the pack ice off Dronning Maud Land. The 31 transects of 1/2 nautical mile (n.m.) width were flown at an elevation of 200 ft and a ground speed of 60 knots and covered 805.6 n.m.2 of pack ice. The overall species composition of the seals was 97.8% crabeater seals, 1.67% Ross seals, 0.34% leopard seals and 0.15% Weddell seals. The density abundance of seals was 2.47 n.m.−2 for crabeater, 0.01 n.m.−2 for leopard, 0.004 n.m.−2 for Weddell and 0.04 n.m.−2 for Ross seals. Leopard seals were largely found near the outer edge of the pack, Ross seals were absent only in the outer pack, whilst Weddell seals were virtually absent in the pack ice. Present throughout, crabeater seals and Ross seals showed a statistically significant preference for the inner pack, the reasons for this being unclear.

Erosion of bedrock from lower intertidal reefs by waves acting on attached plants of bull-kelp (Durvillaea antarctica) was investigated over one year at Macquarie Island, Southern Ocean. At a site on the more sheltered east coast, such erosion occurred during four separate storms, each casting up 834–1078 large kelp plants km−1 of coast, of which 30–45% were still attached to jagged, freshly quarried bedrock fragments over 2.5 cm long. The largest fragment weighed was 74.6 kg; rounded cobbles and boulders attached to kelp plants and weighing up to 102.2 kg (and probably more than 160 kg) were also cast up on beaches. 19–21% of the standing crop of large kelp plants was removed by storms during the year of observation. Break points for 10 kelp stipes were found to be at least 90–161 kg. Total annual erosion by kelp-plucking is at least 1.56 tonnes of rock km−1 of coast. However, in terms of erosion this computes to only 0.1 mm yr−1, far below the rate of uplift of the island.

Two populations of Salpa thompsoni, collected from the Weddell–Scotia confluence area at the end of two summers (1994 and 1995) with contrasting densities, are compared. The present study was aimed at corroborating whether fluctuations in abundance could be related to some life history parameters considered as indicators of growth rate in salp populations, such as the body size of solitary reproductive individuals, number of buds per block or chain in the stolon, and the offspring to parent ratio. No differences were observed in the sizes reached by aggregate individuals, or in the size at which oocyte maturity was attained (moment at which the development of the embryo can be detected). There were no differences in the size reached by the embryos during their residence inside the mother's blastozooid. In 1995, the percentage of non-fecundated blastozooids (which included even the largest individuals) was higher than in 1994. The mean size of the solitary individuals was significantly higher in 1994 than in 1995. The number of buds per block was also significantly higher in most of the stages, confirming that this is the mechanism used by these organisms to produce swarms. This species eventually attains high population densities under favorable environmental conditions such as poor sea-ice cover in winter. Under optimal conditions, the number of potential descendants produced by a single solitary individual would exceed 800.

We describe the distribution and estimate the abundance of seabirds in the Amundsen and southern Bellingshausen seas, and attempt to identify the mesoscale and larger ocean and ice features that explain the birds' discontinuous occurrence patterns. Our general objective was to assess if ocean fronts, especially near the continental shelf break, enhance feeding opportunities for top trophic-level predators. A variety of subsurface thermohaline fronts occurred on both sides of the shelf break, at shallower depths from west to east, and with warmer and saltier water on their northern sides. Pack ice overlaid some of these fronts, especially in the Amundsen Sea. Seabirds comprised either an ice group in pack ice or in polynyas, or an open-water group in waters north of the pack. In the Amundsen Sea, bird densities were near 0 birds km−2 in waters overlying the continental shelf, an unexplained pattern found previously in the Ross Sea but not repeated in the Bellingshausen Sea (5 birds km−2 over the shelf). Both groups were more abundant (densities 3–9 birds km−2) near the frontal zones, the ice edge and the shelf break. In the Amundsen Sea, the distribution of ice-group species was related statistically to proximity of fronts and the pack-ice edge, thermocline slope, and depth of the chlorophyll maximum; water-group distribution was related to distance to the fronts and sea-surface temperature. In the Bellingshausen Sea, distribution of both groups was related to distance to the fronts. Many thousands of petrels, found roosting during daylight on icebergs situated near the shelf break, escaped standard census techniques and, thus, are likely to have diluted positive correlations of avian occurrence patterns with physical features of the environment. While the emperor penguin was seen in high numbers and can dive deep enough to forage within the subsurface fronts, those ocean and food-web processes that apparently affect increased food availability for surface and shallow-diving foragers in the frontal regions remain unclear.

Sterechinus antarcticus inhabits the shelf and the slope of the Weddell Sea and is the predominant echinoid between 450 and 1200 m. Growth lines visible in the half pyramids of the Aristotle's lantern were interpreted as annual growth marks. A Von Bertalanffy growth function was fitted to age-diameter data of 217 specimens (D∞ = 82.4 mm, K = 0.017 y−1, t0 = 1.633 y). Based on 92 trawl samples, a representative size-frequency distriution of S. antarcticus was established. From the growth curve, the size-frequency sample and diameter - weight regressions, mortality and somatic productivity of S. antarcticus were calculated by a size-converted catch curve and the weight specific growth rate method. Gonadal productivity was estimated by an average value for reproductive output of cold water echinoderms. Mortality rate Z as'well as somatic P/B ratio amounted to 0.07 y−1. Annual somatic production was estimated as 0.3 mg m−2y−1, and annual gonadal production as 0.25 mg m−2 y−1 between 100 and 1200 m (0.6 and 0.5 mg m−2 y−1 between 450 and 1200 m).

Data from several summer research cruises in the Antarctic Peninsula region were analysed to calculate length (L50) and age at maturity for the Antarctic krill, Euphausia superba. Length at maturity L50 is defined as the length at which 50% of the krill stock attains sexual maturity. L50 values of 34.65–35.91 mm for female krill are the best estimates for the peak spawning season. Males attain sexual maturity later at L50 values of 43.35–43.71 mm. Length at maturity and length at first spawning are identical for krill. Comparisons with mean length-at-age data show that females mature in the third growth season (age class 2+), while males reach maturity in the fourth year (age class 3+). Both sexes show ‘knife-edge maturity’.