Samples of Loligo gahi from the Falkland Islands Interim Conservation and Management Zone collected in March 1987 were analysed to determine the relationships between mass of reproductive and somatic organs during maturation. There was a progressive increase in mass of the reproductive organs with growth in males, while in females these organs did not show a conspicuous increase in mass until a body mass of c. 40 g was reached. No change was found in the mass of the digestive gland in relation to body mass or in the water content of male and female somatic tissues during maturation. Growth of reproductive organs in L. gahi seems to be supported by diet and not at the expense of somatic tissue.

We describe a long-range migration of a pre-moulting adult chinstrap penguin from Bouvetøya, a small relatively recently established colony, to the South Sandwich Islands, where large, established colonies of this species reside. The trip lasted around three weeks, covered ∼3600 km, and the time of arrival was consistent with the annual moult. The bird did not travel along the shortest path or along a constant bearing, but instead followed what appeared to be a series of two or three rhumb lines of constant bearing. Small southward and northward deviations from the general path were consistent with local water currents. Travel speeds were high during daylight but decreased at night, suggesting that resting or opportunistic feeding occurred preferentially at night. While long-range winter migrations of chinstraps to feeding areas in the vicinity of distant colonies have been previously described, this is the first observation of such a trip during the period between breeding and moulting, and the first record of an individual actually arriving at one of these distant colonies. This has implications for understanding population structure and management of this important Southern Ocean predator.

Certain physical factors, substrate type and ice action appear to be important determinants for ascidian distribution. Three different substrate types were sampled at depths between 0–30 m by SCUBA diving: soft bottoms, hard bottoms and moraine deposits. The species found were Aplidium radiatum, Synoicum adareanum, Distaplia cylindrica, Sycozoa gaimardi, Sycozoa sigillinoides, Tylobranchion speciosum, Corella eumyota, Ascidia challengeri, Cnemidocarpa verrucosa, Styela wandeli, Dicarpa insinuosa, Pyura bouvetensis, Pyura discoveryi, Pyura obesa, Pyura setosa, Molgula enodis and Molgula pedunculata. Highest diversity and patchy distribution was found in less stringent environments, where epibiosis is a commmon phenomenon on stolidobranch ascidians. Differences in stalk development were found in the most abundant species Molgula pedunculata and Cnemidocarpa verrucosa. Ice action may be the main factor that determines the absence of ascidians above 15 m in all the stations sampled.

Methanol-toluene extracts of 17 common Antarctic marine sponges collected from shallow waters in McMurdo Sound in October–December 1989 were tested for suppression of growth of bacteria (gram-positive and negative), yeasts and fungi. Weak to moderate levels of antimicrobial activity occurred in all sponges. Antimicrobial activity was more common when gram-negative bacteria were exposed to sponge extracts; 47% of the sponge extracts caused growth inhibition in one or more gram-positive bacteria, while 100% of the extracts caused growth inhibition in gram-negative bacteria. Particularly strong activity was observed against two species of gram-positive bacteria exposed to extracts of the sponge Latrunculia apicalis and against one strain of gram-negative bacterium exposed to extracts of the sponge Haliclona sp. Antimicrobial responses against yeasts and fungi were generally non-existent or weak, with the exception of the yeast Candida tropicalis, which was strongly inhibited by extracts of the sponges Homaxonella balfourensis, Dendrilla membranosa, Kirkpatrickia variolosa, Gellius benedeni, Cinachyra antarctica and Scolymastia joubinia. Antimicrobial activity in these polar sponges is widespread but generally weaker than that found in temperate and tropical sponges.

This paper documents the previously undescribed terrestrial fauna (mites, nematodes, tardigrades) and flora (liverworts, mosses and lichens) of Marion Nunataks, Charcot Island (69°45'S 075°15'W). Species diversity in all groups is low relative to other Maritime Antarctic sites, probably a twin function of very limited ice-free terrain and extreme isolation. The fauna and flora are wholly immigrant and, with the exceptions of two lichens (Psilolechia lucida and Umbilicaria aff. thamnodes), clearly derived from the Maritime Antarctic. The fauna is unique for the Maritime Antarctic in that it appears to contain neither predatory arthropods nor Collembola (springtails), which are otherwise ubiquitous and important members of the terrestrial fauna of the zone. The flora includes exceptional development of three mosses that are encountered only rarely at latitudes south of c. 65°S, Brachythecium austrosalebrosum, Dicranoweisia crispula and Polytrichum piliferum. The southern limit for several mosses and lichens has been extended. This small and isolated site is extremely vulnerable to accidental human-mediated introduction of both native Antarctic and alien biota.

Kohnen Station (75°S, 0°E, 2892 m) is one of the two drilling sites of the European Project for Ice Coring in Antarctica. Snow falls at Kohnen only a few times a year with comparatively high precipitation rates of 1 mm to over 5 mm water equivalent per event. These events contribute considerably to the total annual accumulation of which the long-term mean value is 62 mm water equivalent per year. For ice core interpretation, it is important to understand synoptic processes leading to such high precipitation rates. Our investigation is based on visually observed periods of heavy snowfall at Kohnen during summer campaigns since 2001/2002. The corresponding synoptic situations can be grouped into three categories. Category I is where occluding fronts of eastward-moving low pressure systems reach the plateau, a fairly frequent occurrence. Category II is where lows or secondary lows formed east of the Greenwich Meridian move to the west (retrograde movement), and frontal clouds influence the plateau. In Category III, large-scale lifting processes (due to an upper air low west of Kohnen Station) lead to cloud formation over the plateau of Dronning Maud Land.

An analysis is made of the climate of the Australian Antarctic station Mawson (67.6°S, 62.9°E) and its hinterland in the light of 30 years of observations and of previous investigations. Data are presented on free atmosphere temperature and wind structure, the synoptic meteorology of the region, solar radiation, surface temperature, sea ice, wind and weather. Emphasis is placed on the characteristics of the shallow south easterly katabatic winds averaging 11.1 m s−1 throughout the year and the frequent periods of intense gale associated with the effects of major Southern Ocean depressions. The climate of Mawson is believed to be typical of much of the coast of East Antarctica in regions where the ice-cap falls steeply to sea level.

Detrital zircon populations from two sandstone samples from the lower member (Johnsons Dock Member) of the Miers Bluff Formation at Hurd Peninsula have been dated by the Sensitive High Resolution Ion Microprobe (SHRIMP) U–Pb method. In one of the samples, zircons as young as early Middle Jurassic (Bajocian) age are present. In the second sample, the youngest detrital zircons are Middle Triassic in age. The detrital zircon age spectra indicate that Permian, early Palaeozoic and Meso- to Neoproterozoic zircon bearing rocks were present in the source areas of the Miers Bluff Formation. The sedimentary rocks are intruded by the Hespérides Point Intrusive diorite stock which yielded a U–Pb zircon crystallization age of 137.7 ± 1.4 Ma (Early Cretaceous, Valanginian). These results indicate that sedimentation of the Johnsons Dock Member of the Miers Bluff Formation is bracketed in time between the Bajocian and the Valanginian. The Miers Bluff Formation has been correlated with the Trinity Peninsula Group from the Antarctic Peninsula, based on sedimentological and structural similarity. Since the Trinity Peninsula Group is older than Middle Jurassic a direct chronological correlation is not supported by our new U–Pb zircon data. However, we suggest that the tectonic setting may have migrated in time with deposition of the pre-Middle Jurassic TPG on the peninsula, to Livingston Island where the maximum age for deposition of the MBF is Bajocian (about 170 Ma).

Multichannel seismic data acquired over the northern Pacific margin of the Antarctic Peninsula, have shown the presence of high-amplitude sub-bottom reflections across part of the South Shetland accretionary prism. Detailed seismic data analysis, such as true amplitude signal recovery, reflection coefficient determinations and closely-spaced semblance velocity analysis, have been carried out in order definitely to assign this bottom simulating reflector to the base of the stability field for methane hydrate. This represents the first evidence of gas hydrate layers in the Antarctic Peninsula region.

Little information is available regarding predator-prey interactions in High-Antarctic coastal systems. In this study, the predation of Trematomus bernacchii (Pisces: Nototheniidae) on Adamussium colbecki (Mollusca: Pectinidae) is described and the related impact on the population structure of the mollusc is hypothesized. Fishes and scallops were collected during several expeditions between 1990/91 and 1997/98 summers, in nearshore waters at Terra Nova Bay (Antarctica). Adamussium colbecki was the main food item of T. bernacchii and an ontogenetic prey-size selection was observed. The predation was mainly on medium size classes of the scallop. These were lacking in the A. colbecki population sampled in the same period suggesting that the impact of fish-feeding on the size structure of the natural population of the mollusc may be substantial. Two size classes of the Adamussium population were not preyed on. Large adults avoid predation either because of the limits for mouth gape in the fish or by swimming avoidance capability, while smaller scallops may not be preyed upon because they are attached through byssus threads to very mobile large adults.

In the Antarctic ciliate, Euplotes focardii, the heat-shock protein 70 (Hsp70) gene does not show any appreciable activation by a thermal stress. Yet, it is activated to appreciable transcriptional levels by oxidative and chemical stresses, thus implying that it evolved a mechanism of selective, stress-specific response. A basic step in investigating this mechanism is the determination of the complete nucleotide sequence of the E. focardii Hsp70 gene. This gene contains a coding region specific for an Hsp70 protein that carries unique amino acid substitutions of potential significance for cold adaptation, and a 5' regulatory region that includes sequence motifs denoting two distinct types of stress-inducible promoters, known as “Heat Shock Elements” (HSE) and “Stress Response Elements” (StRE). From the study of the interactions of these regulatory elements with their specific transactivator factors we expect to shed light on the adaptive modifications that prevent the Hsp70 gene of E. focardii from responding to thermal stress while being responsive to other stresses.

A network for monitoring change in the vegetation communities to assess the impact of future climate changes was established in Victoria Land (Continental Antarctica) in 2002 and 2003. The network is within the framework of the SCAR project RiSCC (Regional Sensitivity to Climate Change in Antarctic terrestrial and limnetic ecosystems), and in cooperation with LGP (Latitudinal Gradient Project) assessing how ecosystem biodiversity and structure may change with latitude and with climate change. The network is composed of 19 permanent plots at nine sites along a latitudinal gradient from Apostrophe Island (73°30′S, 167°50′E) to Granite Harbour (77°00′S, 162°26′E), with a main coastal transect and three subtransects inland from the coast. The sites are representative of the most frequent environmental conditions and the most widespread communities occurring in Continental Antarctica and in Victoria Land. The selected communities show different ecological requirements and have different potential sensitivities to climate change. The vegetation of each plot was described using the RiSCC research protocol, developed originally in the Maritime Antarctic and here adapted, for plot size, to Continental Antarctica. This paper characterizes the vegetation at the sites as the starting point of the long term monitoring.

Determining the millennial-scale behaviour of marine-based sectors of the West Antarctic Ice Sheet (WAIS) is critical to improve predictions of the future contribution of Antarctica to sea level rise. Here high-resolution ice sheet modelling was combined with new terrestrial geological constraints (in situ14C and 10Be analysis) to reconstruct the evolution of two major ice streams entering the Weddell Sea over 20 000 years. The results demonstrate how marked differences in ice flux at the marine margin of the expanded Antarctic ice sheet led to a major reorganization of ice streams in the Weddell Sea during the last deglaciation, resulting in the eastward migration of the Institute Ice Stream, triggering a significant regional change in ice sheet mass balance during the early to mid Holocene. The findings highlight how spatial variability in ice flow can cause marked changes in the pattern, flux and flow direction of ice streams on millennial timescales in this marine ice sheet setting. Given that this sector of the WAIS is assumed to be sensitive to ocean-forced instability and may be influenced by predicted twenty-first century ocean warming, our ability to model and predict abrupt and extensive ice stream diversions is key to a realistic assessment of future ice sheet sensitivity.

We surveyed south polar skuas (Catharacta maccormicki Saunders) in Antarctica for antibodies to a series of viral agents using blood serum and cloacal swabs from 124 adult skuas. There were no ticks on the subjects and we were unable to isolate virus from any individual. Skuas, however, were seropositive to some avian viruses: 16.9% (20/118) had antibodies to infectious bursal disease virus and 10.5% (11/105) were seropositive for Newcastle disease. We found 1.0% (1/98) had antibodies to avian influenza, no evidence of egg drop syndrome (0/48), but 27.8% (10/36) had antibodies to flaviviruses. Clearly south polar skuas encounter a variety of pathogens either in Antarctica or during their migration in the non-breeding season. There was no evidence of disease in skuas, but the presence of antibodies to pathogens indicates the need to continue to search for the origins of these immunological challenges.

A sediment core from Progress Lake, one of the oldest lacustrine sequences in East Antarctica, contains distinct zones dating from a previous interglacial (most likely Marine Isotope Stage 5e, c. 125–115 kyr BP) and the present interglacial (Marine Isotope Stage 1), separated by a transition zone representing when the lake became sub-glacial. Profiles of fossil pigments, determined using high performance liquid chromatography and liquid chromatography-tandem mass spectrometry, show distinct differences in the photoautotrophic community during these two interglacial periods. The first was dominated by algae and purple phototrophic bacteria, with periods of photic zone euxinia indicated by pigments from anoxygenic phototrophic bacteria. Specific chlorophyll a derivatives reveal periods when grazing pressure impacted significantly on the phytoplankton community. The virtual absence of pigments in the transition zone reflects severe restriction of photoautotrophic activity, consistent with the lake having become sub-glacial. Retreat of snow and ice in the late Holocene (3345 14C yr BP) allowed establishment of a less diverse primary producer community, restricted to algae and cyanobacteria. Grazers were severely restricted and oxidative transformation was more important than during the previous interglacial. The pigment data provide a unique and detailed insight in to the evolution of the lake ecology over an interglacial-glacial-interglacial transition and strong evidence that the Marine Isotope Stage 5e interglacial in this region of coastal East Antarctica was several degrees warmer than at present.

The family Acanthonotozomatidae is widely distributed, especially in the Antarctic Ocean. Although many acanthonotozomatids are very conspicuous (they are relatively large and often armoured with teeth on tergites and appendages) very little is known about their biology (Just 1978, Coleman 1989).

Cape Purvis is a conspicuous promontory on southern Dundee Island. It forms a prominent mesa that contrasts with the smooth, shield-like (snow-covered) topography of the remainder of the island. The promontory is composed of fresh alkaline basaltic (hawaiite) volcanic rocks compositionally similar to younger lavas on Paulet Island 5 km to the east. The outcrop is one of the youngest and northernmost satellite centres of the James Ross Island Volcanic Group. 40Ar/39Ar isotopic dating indicates that the Cape Purvis volcano is 132 ± 19 ka in age. The examined sequence probably formed as a lava-fed delta during a subglacial eruption late in the glacial period corresponding to Isotope Stage 6, when the ice sheet surface elevation was 300–400 m higher than at present. A remarkable unidirectional age progression is now evident, from volcanic centres in Prince Gustav Channel (c. 2.0–1.6 Ma), through Tabarin Peninsula (1.69–c. 1 Ma) to Cape Purvis and Paulet islands (132–few ka). The age variations are tentatively ascribed to construction of progressively younger volcanic centres at the leading edge of an easterly-opening deep fault system, although the origins of the postulated fault system are unclear.

Antarctic penguins constitute excellent indicators of organic pollutants (PCBs, DDTs and HCHs), which reach the Antarctic either by atmospheric or maritime transport and are concentrated through the food chains. They are found mainly in lipids, both in adipose and other tissues of the organisms. Tissue samples of four gentoo and one Adélie penguins were collected during the summers of 1991, 1992 and 1993. PCBs and organochlorine pesticides (OCPs) were analysed in the adipose tissue, uropygeal gland, blood, brain, muscle, bone and liver. Organochlorines (OCs) were detected in the majority of the samples. The levels found in extractable fat were higher than in other tissues and the concentrations ranged from 42.3–1159.7 ng g−1 (HCB), from not detected to 39.3 ng g−1 (HCHs), from 30.8–972.3 ng g−1 (DDTs) and from 43.2–1583.6 ng g−1 (PCBs).

Sterechinus neumayeri is an abundant regular sea urchin that lives in the shallow Antarctic waters. This organism has been used as a model system in many fields of the Antarctic biology. Yet, understanding of the evolutionary identity of the species, such as its phylogenetic relationships and divergence time, remains limited. Here, we reconstructed the molecular phylogenies of the species together with two sea urchin species in southernmost South America (Loxechinus albus and Pseudechinus magellanicus), a parechinid species (Paracentrotus lividus) and three strongylocentrotid species (Strongylocentrotus purpuratus, S. intermedius, and Hemicentrotus pulcherrimus) using mitochondrial DNA sequences of 12S rDNA-tRNA(gln) region (877nt) and cytochrome oxidase subunit I (COI, 1079nt). The rate of sequence evolution and the divergence time of the species were then estimated from the trees. The phylogenetic trees reveal that S. neumayeri is a sister group to the lineage of L. albus and P. lividus, and separated from the lineage 24–35 million years ago (m.y.a.). The divergence between S. neumayeri and L. albus coincides with the separation of Antarctica from South America, suggesting that the tectonic event must have provoked the cladogenesis of the species through vicariance.

The ecosystem of the isolated Prince Edward Islands, south of the African continent, is strongly impacted by ocean eddies that are associated with the eastward flowing Antarctic Circumpolar Current. Satellite altimetry has revealed that the archipelago lies in a region of enhanced eddy kinetic energy. In the late 1990s it became apparent that in order to understand the influence of these eddies on the islands’ ecosystem, the source, trajectory and nature of these eddies needed to be studied and understood. To this end a special research project with a strong ocean-going component was designed, the DEIMEC (Dynamics of Eddy Impact on Marion’s ECosystem) programme. In this review we focus on the physical oceanography and summarize the aims, the results and the successes of this South African research initiative. In the vicinity of the Prince Edward Islands, an average of three intense well-defined eddies is observed per year. Their advection speeds are of the order of a few kilometres per day and longevities of 7–11 months. These features, of c. 100 km in diameter and reaching depths of at least 1000 m, transport anomalous water masses across the Polar Frontal Zone.