How many times have you seen statements similar to the following: “Antarctica is a global barometer”, “Antarctica is a warning beacon for global change”, or “Antarctica is a warning beacon for global change”, or “Antarctica is the most sensitive continent to climate change”? The frequency of such statements in this, and other polar journals, is significant. We know that the polar regions are highly sensitive to natural and human induced changes that originate elsewhere on our planet, and the literature is extensive and growing. At the large scale there is increasing evidence of both direct and indirect linkages between climate patterns (e.g. ENSO) in the Pacific and Atlantic oceans and Antarctic climate. At a smaller scale are the follow-on linkages to glacier dynamics, including surface melt, glacier stream flows, lake levels, beaches, sea-ice dynamics and ice tongues. All of these have major repercussions on Antarctic ecosystems. The phase change from water (liquid) to ice (solid) occurs over avery small temperature range (depending on salinity, pressure etc). Thus, for a pond ecosystem, a change in temperature of less than one degree Celsius means the difference between a functioning aquatic ecosystem, and a frozen ecosystem. The recent IPCC report (Climate Change 2001 [3 vols], Cambridge University Press) leaves little doubt of the significant changes to world climate now taking place. As Antarctic scientists we surely must therefore consider that the principal issue to be addressed in Antarctica at present is that of “Responses to a changing climate”.

Publishing is changing rapidly, as is the management of much of the scientific community world wide. Unfortunately there are features of both that should give considerable cause for alarm if one cares to look forward a few years. Let's begin with the remarkable consolidation of wonership in scientific publishing culminating in the latest move - the acquisition of Harcourt by Reed Elsevier- which has been investigated by the Competition Commission in the UK as being potentially against the public interest. Those who buy Reed Elsevier journals at present will know that their subscription rates are some of the highest in the world. It is not obvious that scientists will see any benefit from this takeover. Indeed, what will happen to the provision of information to working scientists as library budgets decline everywhere? Is increasingly expensive equipment for experimental use really more important than the literature? Governments will say that the Web will meet scientists needs to which my reply is that much of its content is uncontrolled rubbish and it certainly does not replace the quality controlled material available in the journals. So our first conclusion for the future could be that consolidation of ownership of journals is bad for science and unless, there is a significant change in library funding, many commercial journals are likely to price themselves out of the general market, leaving only those published by learned societies or charities at an affordable level. Bad news.

Ignorance has never been an excuse in law, but politics clearly plays by different rules. By pretending that global warming simply isn't happening, President George W. Bush is clearly setting new standards for ostriches. Politicians all want to feature in the history books but Bush's ploy to be defender of the American people at all costs is positively breath-taking. Having provided lukewarm support for the Kyoto agreement before the election, to ensure he was not over-trumped by Al Gore, he has now apparently had a change of heart. It is hard to decide if this constitutes outright lying or simple everyday deceit. Apparently the 4000 scientists involved in the recent report by the Intergovernmental Panel on Climate Change and all those other countries that signed up to the Kyoto agreement must be wrong because the Bush advisors from the energy industry say that they are wrong. What world are these people living in?

Modelling future climates is both a very difficult task and one of key importance to our future well-being. Why then would we want to make it more difficult by shortening our perspective to the most recent period, ignoring historical data that would provide the long perspective on key processes? Palaeoenvironmental research has resulted in important advances in our understanding of global changes in oceanic, atmospheric and biotic systems during glaciation and the onset of the current glacial epoch. However, few palaeoenvironmental studies extend farther back than half a million years, and, with the exception of the recently completed Cape Roberts drilling project, vanishingly few consider events prior to the Eocene (55–38 million years ago).

Extensive outpourings of basalt, and to a lesser extent rhyolite, are closely associated with continental break-up and plume–lithosphere interactions. The Gondwana supercontinent began to fragment during Early–Middle Jurassic times and was associated with the eruption of over three million km3 of dominantly basaltic magma. This intense magmatic episode is recorded in volcanic rocks of the Karoo (Africa), Ferrar (Antarctica) and Chon Aike (South America). K–Ar and Rb–Sr whole rock geochronology has consistently failed to produce reliable ages for these volcanic rocks, but in the last four years, the wider application of single grain 40Ar/39Ar and/or U–Pb geochronology has produced more robust and precise dating of the magmatism. This paper reviews the recent advances in high precision geochronology and provides a full recalibrated 40Ar/39Ar dataset. Application of these methods across the majority of the volcanic provinces indicates that approximately 80% of the volcanic rocks were erupted within a short, 3–4 Myr period at c. 182 Ma. This burst of magmatism occurred in the Karoo province at c. 183 Ma and in the Ferrar provinces at c. 180 Ma, and was dominated by mafic volcanism. This peak in volcanism is coincident with a second order mass extinction event at the end of the Pliensbachian when c. 5% of marine families were wiped out coinciding with widespread oceanic anoxia in the early Toarcian. A prolonged period of silicic volcanism occurred along the proto-Pacific margin, prior to, and during the main phase of break-up. Silicic volcanism was initially coincident with the plume related Karoo-Ferrar provinces, but continued over c. 40 Myr, associated with lithospheric extension and subduction along the proto-Pacific continental margin.

Available literature data on age and growth of high Antarctic fish is reviewed and discussed in relation to environmental seasonality. Except for Antarctic toothfish Dissostichus mawsoni, with maximum total length (TL) more than 170 cm, high Antarctic notothenioids are predominantly small species of less than 45 cm TL. Maximum ages reported for small Trematomus species were generally high (18–23 years), and probably comparable to those of some larger channichthyids. Highest longevity is attained by large nototheniids, such as Aethotaxis mitopteryx and D. mawsoni, of more than 30 years. Most high Antarctic fish spawn for the first time at 50–80% of maximum age. Males of some Trematomus species reach spawning maturity earlier than females, but at a higher percentage of maximum age. Pauly's index of growth performance P has been used to compare growth. P for nototheniids is typically between 1 and 2, whereas in channichthyids it is between 2 and 3. Generally, high Antarctic notothenioids exhibit a lower P than those further north. In high Antarctic nototheniids, between 19 and 42 cm maximum theoretical length, growth performance seems to increase from pelagic to benthic fish habit. Thus, although low temperature is a constraint on growth, other ecological factors linked to life style, such as food availability and physiological adaptations, may explain differences in growth performance between fish from the seasonal pack-ice zone and the high Antarctic zone.

Variations of metal concentrations with body size were investigated in kidney, digestive gland and gill of the Antarctic clam, Laternula elliptica, collected from a near-shore habitat at King George Island. Positive relationships for metal concentrations with body size were common among the three organs for most of the metals, while an inverse relationship was found only in the digestive gland for Cu, Zn and Mn. In the gill, concentrations of eight out of the ten metals increased linearly with body size, whilst in the kidney concentrations of Cd, Zn, Pb, Co and Ni were best fitted by quadratic regression curves, viz. increasing continuously until reaching a peak at around an 80 mm shell length. This may reflect specific regulatory activities for the extremely high accumulation of these metals in the kidney, particularly Cd (28–354 μg g−1 tissue dry weight). The overall prevalence of positive relationships indicate net accumulation of these metals throughout life, which may be at least in part associated with the slow growth and long life span of this cold-water bivalve species. The study demonstrates distinct body size-metal concentration relationships in the three organs of L. elliptica, and suggests they may be useful as biomonitors for assessing changes in metal concentrations in Antarctic waters.

The Polychaeta “Sedentaria” collected in Terra Nova Bay (Ross Sea) during the Second Italian Oceanographic Antarctic Expedition (1989–90) have been studied. A total of 1518 specimens have been examined and 43 species, belonging to 14 families, have been identified. A new species of Oweniidae, Myriochele antarctica and a new subspecies of Spionidae, Scolelepis eltaninae nudipalpa are described. Terebellidae was the most important family in number of species, Spionidae, Oweniidae and Orbiniidae in number of individuals. More than 60% of the species are endemic to Antarctic and sub-Antarctic areas.

Recently collected material from west of the Antarctic Peninsula has proven to be consistent with Nymphon gerlachei Giltay, 1935, previously known only from the holotype. The information now available on its intraspecific morphological variability has allowed the distinctions between this species and N. charcoti to be established.

Short and long-term exposure to elevated temperatures were studied in the Antarctic stenothermal protobranch bivalve Yoldia eightsi (Courthouy) from Potter Cove, King George Island (South Shetland Islands, Antarctica). Above a breakpoint temperature of 2°C – the upper habitat temperature for the Potter Cove Y. eightsi stock – both routine (RMR) and standard metabolic rate (SMR) increased steeply. The fraction of metabolism allocated to SMR, as well as the number of intervals of elevated activity per hour increased significantly with temperature. During acute exposure, ATP concentrations in the foot muscle peaked at 2°C and fell at 5°C, whereas superoxide dismutase (SOD) activity decreased upon warming. Slow stepwise warming to a final temperature of 11°C resulted in a significant decrease of SOD activity. Malondialdehyde concentration increased compared with controls at 0°C. In contrast to the effect of short-term exposure, tissue adenylate concentrations displayed a mild increase at higher temperatures during slow warming, indicating an acclimation response. A switch to anaerobic energy production could not be observed up to 11°C, demonstrating a higher level of thermal tolerance than in other Antarctic ectotherms, or a failure of the relevant pathways in Y. eightsi. The imbalance between pro- and antioxidant processes upon warming indicate oxidative stress to be one feature accompanying early heat stress in Y. eightsi.

We sampled soils in the McMurdo Dry Valleys to determine the habitats that were suitable for extreme for soil invertebrates. Suitability was assessed by comparing nematode species diversity and abundance, and tardigrade and rotifer abundance as related to soil properties at three spatial scales: landscape (across Taylor, Wright and Victoria valleys), at three distant locations within valleys, and within small plots (1 m2). Extreme environments were characterized by the lack of nematode abundance and diversity, high salinity, low soil moisture and organic carbon, and higher elevation or a geographic location less accessible for dispersing organisms. Suitable habitats were more frequent near the coast and at lower elevations. Extreme habitats could be defined based on one environmental factor, but more typically a set of interrelated soil and environmental factors appear to determine the abundance and composition of the soil community. The three Dry Valley nematode species occupied distinct regions of a multivariate biplot relating soil chemistry and moisture. Scottnema lindsayae is unusual for its ability to live in a wide range of extreme soil habitats. Our research shows that in the McMurdo Dry Valleys, life flourishes in suitable soil habitats and that extreme habitats (“no invertebrates”) can be defined.

The mental barbel, an important diagnostic character among notothenioid fishes of the family Artedidraconidae, is highly variable in Pogonophryne scotti. A collection of 92 specimens of this species from the South Orkney Islands, comprising both sexes and a wide range of sizes, was studied to determine intraspecific variation in barbel size, shape and ornamentation (development of papillae and folds, especially on the tip). Four distinct barbel types, based on external morphology, are represented in this material: scotti (4.3%), phyllopogon (28.3%), dolichobranchiata (4.3%) and brainlike (38.1%). Indeterminate barbels (25.0%), observed in specimens of both sexes and all sizes, exhibit varying degrees of ornamentation and suggest that all barbel types represent the range of variability in P. scotti. There is no correlation between sex and barbel type. Barbels exhibit negative allometric growth relative to body size. Specimens of at least 119 mm SL generally exhibit greater development of the terminal expansion, resulting in a convoluted brainlike appearance previously unrecorded for P. scotti. Indeterminate and phyllopogon barbels are most common among specimens of 119–210 mm SL. All barbel types are similar histologically. A core of pseudocartilage is surrounded by connective tissue, and the entire barbel is well supplied with blood vessels and nerves. Papillae and folds are dermal projections covered by epidermis. The variation exhibited by the barbel of P. scotti. formerly served as the basis for distinguishing this species from the invalid species P. phyllopogon and P. dolichobranchiata. Such intraspecific variation is atypical for Pogonophryne but underscores the need to fully validate any taxonomic character.

Concentrations of dissolved monocarbohydrates (MCHO) and polycarbohydrates (PCHO) were analysed in a variety of ice habitats from summer Weddell Sea sea ice (surface ponds, ice cores, gap layers and platelet ice). The dissolved organic carbon (DOC) pool in these habitats was also measured and the contribution of carbohydrate to this pool was assessed. The DOC concentrations within all sea ice habitats were high compared to surface seawater concentrations with values up to 958μMC being measured. Total carbohydrates (TCHO) were highest in the ice cores and platelet ice samples, up to 31% of the DOC pool, a reflection of the high algal biomass in these two habitat classes. TCHO in the other habitats ranged between 10% and 29% of DOC. The ratios of MCHO to PCHO varied considerably between the ice habitats: in surface ponds and ice cores MCHO was 70% of the TCHO pool, whereas in gap layers and platelet ice there were lower PCHO concentrations resulting in MCHO being 88% of TCHO.

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.

A mathematical model was used to simulate interannual patterns of biomass accumulation within benthic microbial mats of two Antarctic lakes. Lakes Hoare and Vanda are in the Dry Valley region of Southern Victoria Land, and are both perennially ice covered. The model combines experimentally derived observations of light/photosynthesis relationships and rates of respiration of mats from a range of depths in these lakes, with data on incident radiation and the optical properties of the ice and water column. The model was used to estimate daily and annual production and, using measured carbon content, the potential vertical accumulation of the mats over a year. An annual pattern of photosynthesis was predicted for both lakes, with net production from October to February and net respiration at other times. Predicted rates and patterns of net photosynthesis were remarkably similar in the two lakes, despite differences in light climate: the ice of Lake Hoare transmits 1–4% incident radiation, whereas that of Lake Vanda transmits up to 20%. Maximum daily rates of 15–20 μg carbon cm−2 were predicted to occur at approximately 10 m depth in both lakes. Maximum annual rates of carbon fixation (at 10–12 m depth) in both lakes were c. 1.2 mg carbon cm−2 equating to approximately 0.1–4 mm vertical accumulation of mat each year. Experimental studies of microbial mats in the lakes revealed horizontal laminations of similar thickness to model estimates, supporting the hypothesis that these were annual layers. Differences between model estimates and observations were found in deeper water in Lake Vanda, where considerably more material accumulated than was predicted.

Geolocating-time-depth-temperature-recorders (GLTDTR) provided a continuous record of diving behaviour in relation to water temperature for ten female southern elephant seals from Macquarie Island during their post-breeding trips to sea. Four water bodies were determined from depth/temperature profiles recorded by the GLTDTRs. These water bodies corresponded to Sub-Antarctic Mode Water (SAMW), Polar Front Zone Water (PFZW), Polar Front Water (PFW) and Antarctic Water Masses (AWM). Thermal structures within these water bodies did not influence seal diving behaviour. Overall mean dive depth, nocturnal dive depths, diurnal dive depths and dive duration were similar in all areas. However, individuals did change behaviour as they moved between different water bodies. Seals also used different water bodies in the two different years of the study. We suggest that variations in foraging behaviour among seals are a result of prey distribution associated with local oceanographic conditions, but also reflect important individual foraging strategies within thermal zones.

Southern elephant seals haulout on land to moult, breed and for a third, unknown reason, which we refer to as the winter haulout. We used long-term mark-recapture data to estimate participation levels in the winter haulout by southern elephant seals at Marion Island. There was no evidence that participation levels varied between cohorts or between years. Participation differed between sexes, with males being more likely to haulout in winter, except in the first year of life where participation was equal. Within each sex, both age and reproductive status influenced participation, but age seemed to be the most influential determinant. Generally, immature male individuals hauled out year after year in winter. The results did not allow speculation as to the purpose(s) of the winter haulout.

Allozyme electrophoresis was used to assess genetic variability and differentiation in 22 populations of Gressittacantha terranova Wise (Hexapoda, Collembola) from a coastal area of Victoria Land between the Mariner Glacier and the Nansen Ice Sheet. Allelic frequencies were determined at five enzyme loci: Phi, Pgm, Hk, Mpi and Mdh. Levels of variability, estimated as rates of heterozygosity, were higher than those calculated for the same loci in taxonomically related and non-related species of non-Antarctic Collembola. Thus, in spite of the ecological simplicity of Antarctic terrestrial ecosystems, G. terranova is characterized by high levels of genetic variability, and the 22 populations could be divided into three geogaphic groups, separated by the Aviator and Campbell glaciers. Genetic differentaton reflects the geographic arrangement of the populations, suggesting that the glaciers are effective barriers to gene flow, and that the patchy distribution of collembolan species in Antarctica has the potential to induce, in the long term, microspeciation processes. Interestingly, detectable genetic differentiation was observed between six populations collected at Edmonson Point, even though these are very close to each other, indicating the impact of geographic isolation even within short distances. The only exception to the congruence between genetic and geographic structuring was provided by the population of Apostrophe Island, for which a recent introduction with individuals coming from southern populations is suggested.

Eighteen paired sites (adjacent to vs away from sea bird nests) and six transects (downslope of nests) across Vestfold Hills were sampled for vegetation, soil nutrients, soil water content and percent rock cover. Three moss and 17 lichen species were recorded, including a new record for the lichen Sarcogyne privigna. Sites adjacent to nesting areas generally had higher soil N and P than sites away from nesting areas; however, larger differences between site locations than within site pairs suggests considerable variation in nutrient input between nesting areas and/or redistribution of nutrients by meltwater around nests. Along transects below nesting sites, average soil total N declined from 0.22% to 0.05% within 2 m from the nest, while average total P declined more gradually from 2343 ppm P to 697 ppm P at 30 m from the nest. Moss and lichen species diversity and mean lichen species abundance were higher in sites adjacent to compared with away from nests. Data from site pairs and transects showed that lichen diversity and abundance increased with increasing soil nutrients, with soil P having a stronger influence than soil N. In contrast, soil nutrients were not significantly associated with moss diversity or abundance. Instead, number of moss species and abundance were positively associated with soil water content.

A limited sampling campaign on the main island of Îles Kerguelen revealed 170 freshwater diatom taxa, belonging to 29 genera. Four different communities were distinguished in two major groups, being determined principally by habitat type. The Fragilaria vaucheriae–Fragilaria germainii assemblage occurs exclusively in running waters. The three other communities, observed in standing waterbodies, are separated by their geographical position on the island with the Fragilaria exigua–Aulacoseira alpigena and the Fragilaria exigua–Fragilaria vaucheriae assemblages, mainly found in the Lac Studer area and the Fragilaria pinnata var. pinnata assemblage, recorded near the coastal line and the research station. Analysis of different waterbody types revealed the habitat preference of the various diatom taxa and identified a diatom flora for running waters and one preferring stagnant waterbodies.