In 1972 the United Nations Conference on the Human Environment called for a ten year moratorium on commercial whaling. The International Whaling Commission (IWC, then made up of 14 member governments) did not accept this resolution, taking the view that regulation by species and stocks was the more practical method of whale conservation. In the following years it reduced catches, introduced a new management procedure, and embarked on an international decade of cetacean research.

Scales and whole otoliths were used for age estimation of juvenile Notothenia rossii specimens collected at Potter Cove, King George Island, South Shetland Islands, between 1983 and 1988. Results from the analysis of both types of material showed 96.7% agreement. Likewise, the examination of otolith cross sections of chosen specimens confirmed in all the cases the age readings obtained from the second whole sagittal otolith. Although the commonly accepted 1 July was used as the birth date of the fish for age calculations, data indicate that 1 October is closer to the biological birth date, since this species hatches in Spring. The length-age range of the fish was 18–44 cm and 3–7 years respectively, which fits well with the known length-age distribution of juvenile specimens of the species in the fjord. A comparison between observed and back-calculated mean length of age group 3 (24.6 and 25 cm respectively) indicated that not only the larger fish but the full size range of this age group was represented in our samples. Mean length data at age presented here are similar to the ones reported for fish from Admiralty Bay, King George Island, but differ from those of fish caught off Elephant Island. The use of whole otoliths for age estimation of juvenile N. rossii proved to be a reliable method with a precision of one year but, this might not be an appropriate technique for adult specimens.

About 1500 photographs from three different areas along the eastern Weddell Sea shelf and slope were analysed with respect to their sponge fauna. On the basis of material collected in concurrent bottom trawls, 34 sponge taxa were identified. Cluster and multidimensional scaling analysis showed the sponges to belong to different associations. Spatial extension of the associations is judged to be between several hundred meters and about 2 km. A deeper association (390–1125 m) on predominantly muddy substrates along a transect at Halley Bay is characterized by four opportunistic demosponge species; a second association on harder substrate in shallower depths (99–225m) off Kapp Norvegia is more diverse, with hexactinellids as one dominant component. A third cluster, comprising both Halley Bay and Kapp Norvegia stations (458–626 m), is dominated by four species which constitute a subcluster within the Kapp Norvegia sponge association. Densities vary strongly within clusters and in between geographically close stations. The species associations are related to different substrates, not to depth. Within single stations most species are patchily distributed. Both association structure and species distribution within single stations can be explained on the basis of the biology of the single sponge species.

Chlorinated hydrocarbons were measured in seven species of Antarctic fish (Pagothenia bernacchii, P. hansoni, Trematomus centronotus, T. newnesi, Chionodraco hamatus, Cygnodraco mawsoni, and Gymnodraco acuticeps) from in the Ross Sea near Terra Nova Bay (74°40'S 164°10'E). Hexachlorobenzene (HCB), pp' DDT and its derivatives DDE and DDD, and about 20 congeners of polychlorinated biphenyls (PCBs)were found in muscle and liver. Levels of pp′ DDE were positively correlated with body length in P. bernacchii and the plot of concentrations showed higher values in males than females of the same body weight class. The results confirm the presence of these chlorinated hydrocarbons in the Antarctic marine food chain and an increase of PCBs with respect to DDTs. The “fingerprint” of C. hamatus is different from that of other Antarctic organisms and of fish from other parts of the world, suggesting possible metabolic differences.

An obligately anaerobic bacterium that lacked a cell wall was isolated from the hypolimnion of Ace Lake, Antarctica. Cells were very pleomorphic, forming cocci, filaments up to 25 μm in length, and annular shapes. The organism was morphologically very similar to some members of the class Mollicutes which contains two genera of obligately anaerobic bacteria, Anaeroplasma and Asteroleplasma. Like members of the class, the isolate was resistant to high concentrations of penicillin (1000 Units ml-1). Similar to Anaeroplasma, the organism had a low DNA G+C content (29.3±0.4) and produced hydrogen, carbon dioxide, acetic acid, lactic acid and succinic acid from the fermentation of glucose. However, the taxonomic status of the strain remained unclear as, unlike members of the class Mollicutes, the isolate had a relatively large genome size (2.26±0.11 × 109 daltons), did not pass through 0.45 μm pore size filters, and did not form typical mycoplasma-like colonies. The organism was psychrophilic with an optimum temperature for growth between 12°C and 13°C. A phenotypic description of the organism is given and the ecological role of the organism is inferred from its phenotype and the characteristics of its Antarctic habitat.

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 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.

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.

Levels of polyhydric alcohols and oligosaccharides in the lichens Umbilicaria decussata and Usnea sphacelata were measured in samples obtained from unpolluted and polluted sites on Bailey Peninsula, Windmill Islands, Budd Coast. Undisturbed lichen possessed levels of these compounds (33 and 20 mg g-1 dry weight respectively) typical of those found in lichens from temperate climates. Plants from sites severely polluted by alkaline cement dust, derived from concrete mixing activities, possessed significantly lower levels (P < 0.01) of these intracellular constituents. Levels of chlorophyll a in Umbilicaria decussata were significantly correlated with total polyols + sugars (r2 = 0.88). We suggest that environmental impacts on Antarctic vegetation may be measured by parallel determinations of these two parameters on sensitive lichen species such as Umbilicaria decussata.

Five species of Umbilicaria are described, three of which, U. africana, U. krascheninnikovii and U. nylanderiana, have not been previously recorded from Antarctica. Distributional patterns and morphological characteristics of these species are discussed.

An examination of 111 fish of eight species, including 92 immature Notothenia rossii Richardson revealed nine acanthocephalan species, including four Echinorhynchida occurring in the alimentary tract and five Polymorphida in the body cavity. Echinorhynchida were much more numerous (87% specimens of 4855 collected), especially Metacanthocephalus johnstoni Zdzitowiecki (the dominant species) and Aspersentis megarhynchus (Linstow). The Polymorphida parasites of seals (three species) were more abundant than species parasitic in birds (two species). Association of most of species, (except Corynosoma bullosum (Linstow) and Echinorhynchus spp.), with the inshore (fjord) environment was confirmed. The species diversity, prevalence and density of infection increased with the size of immature N. rossii. Differences in acanthocephalan occurrence and changes with time are related to differences in host distribution and abundance. For example, the occurrence of C. arctocephali in N. rossii at South Georgia is related to the increase of the fur seal population. A list of acanthocephalans in fish at South Georgia and the South Shetland Islands (14 species in total) is included.

Retention of mineral elements in precipitation by mosses and lichens involving ion exchange and chelation mechanisms is a source of nutrients for these biota growing on rocks and nutrient poor soils (Brown 1987, Crittenden 1989). In qualitative work not involving nitrogen (N) Allen et al. (1967) demonstrated that fresh Antarctic mosses treated with hydrochloric acid could retain Na, P, Ca and K after leaching with concentrated solution of these elements. Ahumic fellfield soils are widespread in Antarctica and support sparse plant growth. This short note reports the results of work designed to show that fellfield soils and plants may obtain most of their N from atmospheric precipitation.

A hermit crab assigned to Paguristes sp. is described from James Ross Island, Antarctica. The fossil was obtained from the Gamma Member of the Santa Marta Formation of late Campanian age. The specimen is associated with an external mould of the gastropod Taioma, that was encrusted by a colony of ascophoran bryozoans. Another specimen of Taioma shows typical predatory marks in the outer lip that are attributed to the action of pagurids. It is concluded that the particular dwelling habits of the hermit crabs, their symbiosis with bryozoan, and their predatory activities were already established by the end of the Cretaceous.

South Georgia is a highly glacierized island with a range of glacier types including corrie, valley and tidewater ice bodies. Glaciologically, it occupies a strategic location between South America and the Antarctic Peninsula and is potentially an important locality for establishing glacier-climate relationships in the region. Baseline surveys of ice front positions and ice surface profiles have been repeated to determine recent changes in several glacier types. Corrie and small, land-based valley glaciers have continued to thin and recede during the period of study, following an advance during the 1930s. Their behaviour primarily reflects the effects of seasonal temperature variations in controlling net balances, and particularly the climatic warming since 1950. The larger valley and tidewater glaciers display a lagged response and in the 1970s were at their most advanced positions since the Little Ice Age of the 17–19th centuries. However, in the last few years they too have commenced to thin and recede.

An ice dam with a former impoundment volume of 1.1 × 106 m3 is reported from the Vestfold Hills, East Antarctica. The ice of the dam was derived from wind-drifted snow subsequently changed into ice by normal summer melt and freeze processes. The reformation (after 1979 and 1987) and failure of this ice dam (during 1987 and 1990) indicates the potential for the release of geomorphologically significant flows in a polar climate. The origin of a nearby fluvially eroded channel is attributed to the release of an ice-dammed impoundment. The potential of such flows for reworking glacial debris may be important when considering the sedimentology of former proglacial areas.

A nearly complete lower pharyngeal tooth-plate from a large (over 60 cm long) fossil wrasse (Perciformes: Labridae) was recently recovered from the middle to late Eocene La Meseta Formation on Seymour Island, Antarctic Peninsula. This find increases the number of teleosts from the Eocene of Antarctica to five taxa, and further illustrates the diversity of the ichthyofauna in the Eocene Weddellian Sea prior to wide-scale climatic change in the Southern Ocean. The fossil wrasse represents the first occurrence of this family in Antarctica, and is one of the oldest fossils of this family from the Southern Hemisphere. Wrasses are not found in Antarctic waters today, and probably became extinct during the Oligocene due to a combination of climatic change, loss of shallow-water habitat, and changes in the trophic structure of the Wedell Sea.

The rocks of the James Ross Basin consist of a 6 km-thick, relatively complete sequence of Early Cretaceous-Eocene marine sediments, which are remarkably well exposed over Seymour, Vega, James Ross, and Snow Hill islands. Throughout most of the sequence, macrofossils and microfossils are extremely abundant and diverse.

Measurement of pressure fluctuations provides the best means of detecting atmospheric internal gravity waves at the Earth's surface. We have developed an instrument which is sufficiently sensitive to detect the small pressure fluctuations associated with such waves yet robust enough for deployment in an Antarctic environment. The instrument incorporates several novel features, both in its design and in the method of deployment used. A prototype instrument has been successfully deployed at the British Antarctic Survey's Halley Station during 1989. The design of an experiment using an array of six improved instruments is briefly described.