There is great biological interest in the birds and marine mammals of Antarctica. They are numerous, obvious and apparently well adapted to an extreme and highly seasonal environment. What specific ecological and physiological adaptations have made them so successful? In pursuit of the answers to this biologists, over many decades, have undertaken a wide variety of experiments on seals and birds—especially penguins.

Antarctic science is inter-disciplinary in character, multi-national in execution, and globally relevant. Data management in this environment must be examined from political, scientific and economic perspectives. The Antarctic Treaty calls on parties to exchange and make freely available scientific observations and results from Antarctica, so establishing the political context for addressing data management. The scientific context arises from the increasingly large and complex issues being addressed, including environmental monitoring and global change programmes, while the economic context considers data and information as the primary assets derived from Antarctic expenditure.

In March 1993 the Atmospheric Environment Service's monitoring network across Canada registered ground-level fluxes of solar ultraviolet-B radiation (UVBR) that were the highest on record. This effect was correlated with the spring-time depletion of ozone in the northern upper atmosphere, and AES predicted that the average depletion over Canada could be this severe or worse for the next 15–20 years. These reports heightened awareness amongst the Canadian public as well as the scientific community about the Antarctic ozone hole, and about the most recent UVBR and atmospheric research findings from Antarctica. The causes and biological impacts of high latitude ozone depletion is but one example where information derived from one polar zone is of vital interest to those living in, or otherwise concerned with the other. In this and other research areas the time is appropriate for a bipolar perspective on Antarctica.

As Antarctic Science enters its fifth year, it is time to assess progress and review the opportunities for Antarctic research in the coming years. The journal appears to have filled a useful niche, established arange of regular (and irregular!) contributors, and is taken by the majority of major polar libraries world-wide. Quality of production has improved with new equipment but rate of publication has fallen with increasing numbers of acceptable contributions. Cross-disciplinary papers have been few — but perhaps that is because few Antarctic scientists have undertaken the challenge of cross-disciplinary studies? Glaciology and most aspects of atmospheric sciences are still under-represented.

Our first special issue on the palynology of James Ross Island has been well received and a second, on a Southern Ocean cephalopod symposium, is planned for 1994. These special issues are a bonus to subcribers who get the extra pages free. The editors are keen to receive proposals for other special issues with offers of appropriate funding.

The Antarctic digital topographic database is the outcome of a truly international collaborative project between 11 nations. Data capture was co-ordinated in the UK, under the auspices of the Scientific Committee on Antarctic Research (SCAR), during a two-year period. Over 200 maps, at scales ranging from 1:200 000 to 1:5 000 000, were digitized for the project and reference was made to a similar number of satellite images (mostly Landsat photographic products). Editing and harmonization of the data derived from the different sources has produced a seamless map of Antarctica which has the most up-to-date coastline now available. The topographic database created, to be published on one CD-ROM, will form the foundation for future GIS needs in Antarctic research. Products already derived from the database include digital elevation models and customized maps; the latter can be reproduced by research groups to meet their own mapping needs.

Six species of anascan cheilostome Bryozoa are described from Antarctica. Apiophragma gen.nov. is introduced for Megapora hyalina Waters, 1904. Cellaria dennanti Waters, 1904 non MacGillivray, 1895 is redescribed as Swanomia belgica sp.nov. Paramawsonia Androsova, 1972 is restricted to its type species, Cellaria dennanti MacGillivray, 1985. Micropora notialis sp.nov. is distinguished from M. brevissima Waters, 1904. Two new species are described in the genus Cellaria.

The diet of the Antarctic blue-eyed shag Phalacrocorax atriceps bransfieldensis was analysed based on the identification of the prey items in 50 regurgitated casts collected at Duthoit Point, Nelson Island, in February 1991. Fish remains occurred in 100% of the casts and represented 68% by number and 90% by weight of the total prey items. From a total of 2112 otoliths found, 1176 fish specimens were identified belonging to four demersalbenthic species: Harpagifer antarcticus, Notothenia neglecta, Nototheniops nudifrons and Trematomus newnesi. Equations to estimate total length and weight from otolith length are provided. H. antarcticus and N. neglecta were the most frequent (92%) and important by weight (66%) respectively. Cephalopod beaks found indicate benthic octopods as the second group in importance after fish. Other invertebrates such as polychaetes, gastropods, bivalves and crustaceans were only occasional. The presence of algae and stones in the casts is attributed to accidental ingestion. Our results are in general agreement with those published for other Antarctic localities which indicate that P. atriceps is a benthic coastal feeder, with fish as its main food.

Concentrations of mercury were measured in soil and two species of epilithic macrolichens (Umbilicaria decussata and Usnea antarctica) collected along of the coast of northern Victoria Land coast. Most of the soil samples had a very low mercury content, whereas lichens had levels higher than in other remote areas. Although a possible contamination of samples cannot be completely excluded, the relevance to bioaccumulation of the very slow growth rate of lichens and of volcanic activity are discussed.

The consumption of food by the four species of breeding penguins at the Prince Edward Islands is assessed on an annual and seasonal basis. Total annual food consumption was estimated at 880 000 t, of which king penguins accounted for 74%, macaroni penguins 21%, rockhopper penguins 5% and gentoo penguins <1%. Pelagic fish, almost entirely myctophids, were the most important prey (70% of total prey biomass), followed by pelagic crustaceans (18%) and cephalopods (11%). Demersal fish and benthic crustaceans accounted for <1% of total consumption, being consumed only by gentoo penguins. Peak demands of between 2 and 3.3 × 106 kg d−1 occurred from October–December when three of the four species were breeding, including the two demi-populations of king penguins. Food demand decreased to 1.2 × 106 kg d−1 during winter when only king and gentoo penguins were present. Much of the prey are presumably captured within 300 km of the islands. Assuming an even distribution of foraging effort within their respective foraging ranges, rates of food transferred to penguins in November ranged from 4.1 × 10−3 g m−2 d−1 for macaroni penguins to 1.24 × 10−2 g m−2 d−1 for king penguins. In mid-July, transfer rates to king and gentoo penguins were 3.9 × 10−3 g m−2 d−1 and 6.7 × 10−3 g m−2 d−1, respectively. The importance of pelagic myctophid fish to penguin populations at the Prince Edward Islands is clear.

Maritime Antarctic freshwater lakes and their catchments are inherently simple systems in an environment which is characterized by strong seasonality. Such lakes offer excellent opportunities to study the interaction of water chemistry and plant communities. The response of diatom species to environmental gradients was assessed by constructing a diatom and water chemistry dataset from 59 lakes at two locations (Livingston Island, South Shetland Islands and Signy Island, South Orkney Islands). Results indicate that diatom species abundance is predominately related to nutrient and salinity gradients. The dataset will be used to create transfer functions which can be applied to sediment core diatom assemblages to reconstruct historical patterns of lake chemistry.

Diving behaviour of chinstrap penguins (Pygoscelis antarctica) was studied in four adults brooding chicks on Seal Island, South Shetland Islands, Antarctica. During foraging trips to sea, chinstrap penguins made shallow, short duration dives almost continuously, for the most part within 50 m of the surface. Diving effort was concentrated during the daylight hours (10h00-15h00), although a second peak in effort was seen around midnight (22h00-02h00). These peaks were possibly due to the constraints of visual location of prey, chick provisioning, or the need to take advantage of diurnal changes in krill swarm densities or behaviour. It was estimated that most effort was concentrated 3-20 km from shore. Dive depth and duration averaged 31.0 m (± 26.3m) and 72s(± 36s), respectively. Maximum dive depth and duration were 121m and 180s, respectively.

The main water body at Hope Bay, Boeckella Lake, was sampled at four sites for phytoplankton during summer 1991 to assess the influence of nutrients from nearby penguin rookeries on both phytoplankton density and composition. The site located at the base of the rookeries had total phosphorus values comparable to those reported from the most eutrophic Antarctic lakes. During the ice-free period most of the Chlorophyceae and Cyanophyceae recorded were concentrated at this site. Phytoplankton density increased strongly in the area opposite to the rookeries where ice began to form; an under-ice bloom of Ochromonas aff. ovalis (Chrysophyceae) was observed in this area.

Data on the growth (20 species) and productivity (19 species) of Antarctic and subantarctic macrobenthos were compiled from published and unpublished sources. Differences in the production/biomass (P/B) ratio between Antarctic, Arctic and non-polar populations were examined using a set of 363 data arrays (327 non-polar, 26 Antarctic, 10 Arctic). Each array contained annual P/B ratio, mean individual body mass, geographical latitude, water depth, bottom water temperature and the nominal variables TAXON (Mollusca, Crustacea, Polychaeta, Echinodermata) and REGION (Antarctic, Arctic, non-polar). The P/B ratio was found to vary with body mass, taxon, temperature and water depth. P/B ratios of Antarctic and Arctic populations were significantly lower than those of non-polar populations. For Antarctic populations this difference could be explained completely by the effects of temperature and water depth. The strikingly high biomass of many Antarctic benthic communities is probably related to adaptations to low and oscillating food levels, and particularly to the low maintenance energy requirement associated with the low ambient temperature.

Within the Western Ross Sea, there are six emperor penguin colonies of widely different size that occur exclusively on sea ice. In 1990 a survey of all six sites, two by close overflights and four from the ground, showed that the breeding habitats were highly variable. The most important physical characteristics of these habitats appear to be stable fast ice, nearby open water, access to fresh snow, and shelter from the wind.

The geographical distribution and depth zonation of Eusirus perdentatus Chevreux, 1912 in the eastern Weddell Sea and adjacent Lazarev Sea (Antarctica) is described. A total of 963 individuals of this carnivorous predator caught during six successive cruises at 71 stations between 176 and 799 metres water depths were used. Individuals of E. perdentatus have been kept alive for nearly five months in the laboratory. During this period females released 53 juveniles in April. Oocytes and embryos of females have been counted and measured. The duration of embryonic development in E. perdentatus was estimated at c. 12 months, using an empirical relationship based on the mean diameter of 4390 fertilized eggs. There is strong evidence that this species is semelparous with hatching of juveniles at the end of austral summer. Two methods, herein termed as Year Class Model and Moult Class Model, have been applied in order to describe the growth of females by means of cumulative length-frequency data.

A census of the breeding population of Antarctic fur seals (Arctocephalus gazella) at South Georgia was carried out during the 1990/91 breeding season. Using counts of adult females ashore at the breeding grounds during the pupping period, together with corrections for the likelihood of a female being ashore at a census and for pregnancy rate (71% in 1990/91), pup production was estimated as 269 000 (95% confidence intervals 188 000-350000). The breeding population in 1990/91 was reduced at long-term study sites probably because of limited food availability. Data from these sites were used to estimate the pup production of the population had 1990/91 been a typical year. Based on values from 1983/84 to 1990/91, pup production in 1990/91 would have been 378000 (se=19100) if it had been an average year. The annual increase in pup production from 1976/77 to 1990/91 has declined to 9.8% since the initial period of population expansion in the 1950s and 1960s. Increased population size has led to an expansion of the breeding range at South Georgia.

The 16S rRNAs of nine new species of prokaryotes, that had been isolated from four lakes of the Vestfold Hills, have been sequenced. These sequences were compared with those of their closest taxonomic relatives available from publicly available databases. The Antarctic species were of wide diversity with representatives from the domains Archaea and Bacteria (sensu Woese). Generally, they were most closely related to organisms from marine environments. The sequence dissimilarity between the rRNA sequences of the Antarctic strains and their nearest known relatives suggest they diverged from each other much earlier than the establishment of their modern Antarctic habitat. The conserved nature of the 16S rRNA molecule suggests it may not be as useful for detecting evolutionary change in Antarctic prokaryotes as distinct from non-Antarctic prokaryotes. Although the optimal temperature for growth of each species is well above the temperature of its environment, each has a reduced optimal temperature for growth when compared with its taxonomic counterpart from non-Antarctic environments. The vast majority of Antarctic prokaryotes remains to be described.

Five volatile organic compounds were identified throughout 1991 in the hypolimnion of Organic Lake. These were dimethylsulphide (DMS), dimethyldisulphide (DM2S), dimethyltrisulphide (DM3S), dimethyltetrasulphide (DM4S) and phenol. The concentration of these compounds increased with lake depth. The concentration of DMS and DM2S was higher in the sediment than in the water column. Carbon disulphide occurred only in the sediment. DMS was the only volatile organic compound detected in the epilimnion of the lake, where its concentration increased from winter onwards. The source of DMS was not dimethylsulphoniopropionate (DMSP). This was determined by hydroxylation of the sample with NaOH. There was no change in the concentration of DMS but the concentration of DM2S increased dramatically while the concentrations of DM3S and DM4S decreased concomitantly. This has important implications in the estimation of DMS derived from DMSP by hydroxylation when organic polysulphides are also present. The stability of the hypolimnion of Organic Lake was reflected by the lack of change in temperature, density, redox potential and the relatively constant concentration of volatile organic compounds throughout the year. Potential sources of the volatile organic compounds are discussed in relation to the isolated nature of the lake.

During January-March, 1991, the distribution and floristic composition of the phytoplankton around Elephant Island, Clarence Island and the northern end of King George Island were determined in relation to physical oceanographic conditions and to proximity of the shelf-break and continental slope. The study area included 180 stations, and c. 5400 km of transects providing continuous measurements of salinity, temperature, beam attenuation, and chlorophyll a (chl a) concentrations in surface waters. The richest phytoplankton areas (2-4 μg chl a 1-1) were generally found associated with a strong salinity front, extending north of King George Island to north of Elephant and Clarence Islands. Data on the phytoplankton community suggest that shelf waters were charaterized by low biomass and a nanoplankton population, while in and just north of the front the biomass increased and there was a shift to a diatom-dominated microplankton population. This is thought to be related to increased stability of the water column just north of the front. The salinity front ran more or less parallel to the continental shelf-break, but its exact position varied during the period of study. It was generally associated with transition water (Type II) or with Weddell-Scotia Confluence water (Type III).

Thirty eight strains of Antarctic bacteria were screened for the ability to produce polyunsaturated fatty acids (PUFA). Five strains contained eicosapentaenoic acid (20:5ω3) in the range of trace to 3.3% of total fatty acids, and up to 1.4 mg g-1 dry weight. Thirteen strains produced polyunsaturates including 18:2ω6, 18:3ω3, 18:4ω3 and 20:4ω6 in the range of trace to 7.0% of total fatty acids. Although the data set is currently small, the proportion of Antarctic strains found to produce PUFA's is higher than that found for temperate marine bacteria (and is similar to that recorded for barophilic bacteria). This suggests that the Antarctic environment has naturally selected for bacterial strains capable of maintaining membrane lipid fluidity by the production of PUFA. These results highlight the potential of Antarctic bacteria for possible consideration in the industrial production of PUFA. These results highlight the potential of Antarctic bacteria for possible consideration in the industrial production of PUFA. The fatty acid composition of Flectobacillus glomeratus is reported and discussed in relation to other closely related Antarctic flavobacteria. Fatty acid composition is also shown to represent an important chemotaxonomic tool to aid with the identification of Antarctic bacteria.