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.

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.

Cephalopod remains from the stomachs of four pilot whales Globicephala melaena (Traill, 1809), two bottlenose whales Hyperoodon planifrons Flower, 1882 and eight Commerson's dolphins Cephalorhynchus commersonii (Lacepede, 1804) stranded in Tierra del Fuego, Argentina were identified and measured. A total of 3365 lower beaks (mandibles) were identified and measured and from the rostral, crest and hood length, total wet and dry mass, mean mass and mean mantle length for each taxon were estimated. Over 68% of the cephalopods eaten by the pilot whales and all cephalopods eaten by the bottlenose whales were oceanic squid species (oegopsids). The Commerson's dolphins had only eaten shelf species of the families Loliginidae (97.5%) and Octopodinae (2.5%). Sixteen cephalopod families comprising 23 species were represented. In samples from Globicephala melaena, Loligo gahi represented 31% by number and 7.1% by estimated dry mass, Histioteuthis eltaninae, 29% by number and 4.9% by dry mass and the onychoteuthid Moroteuthis ingens 17.2% by number and 51.5% by dry mass. In samples from Hyperoodon planifrons, Histioteuthis eltaninae represented 24.0% of cephalopods by number but only 5.2% by dry mass, Taonius pavo 53% by number but only 2.5% by dry mass and the large onychoteuthid Kondakovia longimana only 2.5% by number but 65.8% by dry mass. In samples from Cephalorhynchus commersonii, the neritic Loligo gahi contributed 97.4% by number and 97% by dry mass and a neritic octopodinid contributed the rest of the cephalopod part of the diet. While the cephalopods contributed the major part of the diets of these particular cetaceans, other remains included fish and polychaete worms.

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’.

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.

Glacial till samples collected from beneath the Bindschadler and Kamb ice streams have a distinct U-Pb detrital zircon signature that allows them to be identified in Ross Sea tills. These two sites contain a population of Cretaceous grains 100–110 Ma that have not been found in East Antarctic tills. Additionally, Bindschadler and Kamb ice streams have an abundance of Ordovician grains (450–475 Ma) and a cluster of ages 330–370 Ma, which are much less common in the remainder of the sample set. These tracers of a West Antarctic provenance are also found east of 180° longitude in eastern Ross Sea tills deposited during the last glacial maximum (LGM). Whillans Ice Stream (WIS), considered part of the West Antarctic Ice Sheet but partially originating in East Antarctica, lacks these distinctive signatures. Its U-Pb zircon age population is dominated by grains 500–550 Ma indicating derivation from Granite Harbour Intrusive rocks common along the Transantarctic Mountains, making it indistinguishable from East Antarctic tills. The U-Pb zircon age distribution found in WIS till is most similar to tills from the west-central Ross Sea. These data provide new specific targets for ice sheet models and can be applied to pre-LGM deposits in the Ross Sea.

An intensive migration of Arctic terns was observed from 7–9 March 1989 in Marguerite Bay (67°50'S 67°30'W). The movement pattern and speed of tern flocks were analysed from time-lapse films of a marine navigation radar. The terns migrated north at altitudes 30–60 m asl along the inner coast of Marguerite Bay. When approaching Pourquois Pas Island, the majority veered to the NNE flying into Bourgeois Fjord. Mean flock size was 11.6 (s.e. = 1.9). The estimated total during the three observation days was about 7600 migrating terns. Analysing flight speed in relation to wind showed that the terns increased their airspeed when flying into headwinds and decreased it with following winds. The terns' airspeeds, with an estimated mean of 11.3 ms-1 (s.e. = 1.3) with no wind effect, were significantly faster than the predicted maximum range speed. It is suggested that the terns were migrating on a connecting route between the pack ice of the Bellingshausen and Weddell Seas, involving a flight across the Antarctic Peninsula. Topographical conditions are favourable for such a passage close to the observation site in Marguerite Bay, where the distance across the 1500 m high ice cap of the Antarctic Peninsula is only 37 km. It remains to be clarified if the suggested migration route is of importance for regional tern populations only, or if it is part of a circumpolar Antarctic migration pattern.

The eight dominant culturable members of an Antarctic fellfield soil bacterial community were four Arthrobacter species, Sanguibacter suarezii, Aureobacterium testaceum, a Bacillus sp., and a Pseudomonas sp.. All of the isolates grew at 2°C, but two of the Arthrobacter spp. were psychrophilic, while the other six bacterial species were psychrotolerant. However, the fastest growing organisms at low temperatures were not the psychrophiles, and the psychrotolerant Bacillus sp. grew fastest at temperatures up to 25°C. When the growth temperature of cultures was altered, the phospholipid content of the two psychrophilic Arthrobacter spp. decreased, whereas the phospholipid contents of the psychrotolerant spp. either increased or did not change. Only one psychrophilic and one psychrotolerant Arthrobacter sp. modified its polar lipid head-group composition in response to a lowering of growth temperature. The change in Arthrobacter sp. CL2-1 was particularly marked and novel in that at low temperatures phosphatidylethanolamine was replaced completely by a phosphoglycolipid and phosphatidylserine, neither of which was present at higher growth temperatures. All eight isolates altered the fatty acyl compositions of their membrane lipids in a manner that was only partially dependent on taxonomic status. In Bacillus sp. C2-1 the changes were opposite to that predicted on the basis of membrane fluidity considerations. The isolates used different combinations of changes in fatty acid branching, unsaturation and chain length. There was no single strategy of thermal adaptation that was employed and the variety of strategies used did not follow phylogenetic boundaries.

Satellite imagery is used to show that the world's second largest emperor penguin colony, at Halley Bay, has suffered three years of almost total breeding failure. Although, like all emperor colonies, there has been large inter-annual variability in the breeding success at this site, the prolonged period of failure is unprecedented in the historical record. The observed events followed the early breakup of the fast ice in the ice creeks that the birds habitually used for breeding. The initial breakup was associated with a particularly stormy period in September 2015, which corresponded with the strongest El Niño in over 60 years, strong winds, and a record low sea-ice year locally. Conditions have not recovered in the two years since. Meanwhile, during the same three-year period, the nearby Dawson-Lambton colony, 55 km to the south, has seen a more than tenfold increase in penguin numbers. The authors associate this with immigration from the birds previously breeding at Halley Bay. Studying this ‘tale of two cities’ provides valuable information relevant to modelling penguin movement under future climate change scenarios.

The infestation of Weddell seals and several fish species by the anisakid nematodes Contracaecum osculatum and C. radiatum was compared. Nematode numbers in Weddell seal stomachs ranged from 30 560 to 122 640. Third stage larvae from seals and fish were separated into a short and a long type. The short type was related to C. radiatum and the long type to C. osculatum. The short type was more abundant in pelagic fish species, whereas the long type prevailed in benthic fish species. Fish-feeding channichthyids Cryodraco antarcticus and Chionodraco myersi seemed to play an important role as paratenic hosts for the third stage larvae of both Contracaecum species. Different advantageous and detrimental features of a benthic versus a pelagic life cycle under high Antarctic ecological conditions are discussed. Varying abundance of the two nematode species in hosts may be controlled by differences in their life cycles, which follow either a pelagic or a benthic food web. Crucial importance is thus given to the local availability of pelagic versus benthic food resources for Weddell seals.

Particulate organic matter was collected in the coastal waters of Terra Nova Bay during the Oceanographic Campaign of the Italian Antarctic Research Programme in summer (January–February) 1990. Particulate matter composition was analysed for organic carbon and nitrogen, carbohydrates, proteins, lipids, nucleic acids (DNA and RNA) and ATP. A vertical stratification was evident in the study area, and resulted from prior melting of the pack ice. Suspended organic matter in the mixed layer and below the mixed layer differed in quantitative and qualitative composition. Except for ATP, all the biochemical components showed higher concentrations in the mixed layer than in the deeper waters. The particulate organic matter in Terra Nova Bay was mostly detrital and of algal origin.

Isolated fish remains including a tooth of the oldest described frilled shark, Chlamydoselachus thomsoni sp. nov. are described and figured from the Santa Marta Formation (Santonian–Campanian, Late Cretaceous) of James Ross Island, Antarctic Peninsula. Their geological and palaeoecological context is considered in the light of recent geological studies.

To reduce the uncertainty in the calculation of Antarctic solid ice fluxes, the firn depth correction (Δh) in Antarctica is inferred from a steady-state firn densification model forced by a regional atmospheric climate model. The modelled density agrees well with observations from firn cores, apart from a site at the origin of fast flowing West Antarctic ice stream (Upstream B), where densification is anomalously rapid. The spatial distribution of Δh over Antarctica shows large variations, especially in the grounding line zone where large climate gradients exist. In places where the grounding line crosses ablation areas, Δh is zero. Along the remainder of the grounding line, Δh values range from typically 13 m in dry coastal areas (e.g. Dronning Maud Land) to 19 m in wet coastal areas (e.g. West Antarctica).

A proximal fragment of a gill raker identified as belonging to a shark of the genus Cetorhinus was collected from middle Eocene deposits of the La Meseta Formation in the northern part of Seymour Island, Antarctica. This is the first record of a fossil basking shark from Antarctica and one of the earliest records of the genus. The minimum age of Cetorhinidae is middle Eocene. The only living species of the family Cetorhinidae is a very large plankton feeder, Cetorhinus maximus. Basking sharks are unknown in subantarctic or Antarctic waters but occur on both South American coasts today. The evolution of filter-feeding vertebrates is discussed.

Fisher Massif consists of Mesoproterozoic (c. 1300 Ma) lower amphibolite-facies metavolcanic rocks and associated metasediments, intruded by a variety of subvolcanic and plutonic bodies (gabbro to granite). It differs in both composition and metamorphic grade from the rest of the northern Prince Charles Mountains, which were metamorphosed to granulite facies about 1000 m.y. ago. The metavolcanic rocks consist mainly of basalt, but basaltic andesite, andesite, and more felsic rocks (dacite, rhyodacite, and rhyolite) are also common. Most of the basaltic rocks have compositions similar to low-K island arc tholeiites, but some are relatively Nb-rich and more akin to P-MORB. Intermediate to felsic medium to high-K volcanic rocks, which appear to postdate the basaltic succession, have calc-alkaline affinities and probably include a significant crustal component. On the present data, an active continental margin with associated island arc was the most likely tectonic setting for generation of the Fisher Massif volcanic rocks.

The distribution and abundance of free-living arthropods from soil and under stones were surveyed at the Cape Hallett ice-free area (ASPA No. 106), North Victoria Land, Antarctica. A total of 327 samples from 67 plots yielded 11 species of arthropods comprised of three Collembola: Cryptopygus cisantarcticus, Friesea grisea and Isotoma klovstadi and eight mites: Coccorhagidia gressitti, Eupodes wisei, Maudheimia petronia, Nanorchestes sp., Stereotydeus belli, S. punctatus, Tydeus setsukoae and T. wadei. Arthropods were absent from areas occupied by the large Adélie penguin colony. There was some distinction among arthropod communities of different habitats, with water and a lichen species (indicative of scree slope habitats) ranking as significant community predictors alongside spatial variables in a Canonical Correspondence Analysis. Recent changes to the management plan for ASPA No. 106 may need to be revisited as the recommended campsite is close to the area of greatest arthropod diversity.

Eleven aerobic heterotrophic bacteria isolated from soil samples taken at c. 1800 m altitude from La Gorce Mountains, Antarctica, were characterized in terms of carbon source utilization, enzymatic activities and tolerance to environmental stressors. The bacteria typically formed pigmented colonies on agar plates and were initially observed on media designed for isolation of algae and cyanobacteria. The bacteria were purified and assigned to the Actinobacteria, Bacteroidetes or Proteobacteria divisions following 16S rRNA gene sequence analysis. While some of the isolates are most likely to belong to the genera Arthrobacter or Brevundimonas, others may belong to novel genera or species. The Gram-positive Actinobacteria used the widest range of carbon sources for growth. Brevundimonas P7 produced lipases, phosphatases, proteases and glycosyl-hydrolases. The Gram-positive bacteria were more tolerant to freeze-thaw than the Gram-negative isolates. No isolates survived more than 10 minutes ultraviolet irradiation. All isolates were unaffected by 24 h desiccation. This study adds to knowledge of the bacterial diversity of soils from high altitude (1800 m), high latitude (86°30'S) locations within Antarctica.

We present preliminary results of the first detailied surveys of the former Larsen-A Ice Shelf, Larsen Inlet and southern Prince Gustav Channel, where disintegration of small ice shelves in the past ten years has exposed the seafloor. Glacial troughs in the Larsen-A area, Larsen Inlet and Prince Gustav Channel reach 900–1100 m depth and have hummocky floors. Farther south-east, the continental shelf is shallower (400–500 m) and its surface is fluted to smooth, with the density of iceberg furrowing increasing towards the shelf edge. Acoustic profiles show a drape of transparent sediment 4–8 m thick in Prince Gustav Channel, thinning southwards. In cores, this drape corresponds to diatom-bearing marine and glacial-marine mud. In the Larsen-A area and Larsen Inlet, acoustically opaque sediment includes proximal ice shelf glaciomarine gravelly and sandy muds, and firm to stiff diamicts probably deposited subglacilly. These are overlain by thin (up to 1.3 m) glaciomarine muds, locally with distinctive diatom ooze laminae.