The lakes and watercourses are habitats for various communities of cyanobacteria and algae, which are among the few primary producers in Antarctica. The amount of nutrients in the mineral-poor Antarctic environment is a limiting factor for the growth of freshwater autotrophs in most cases. In this study, the main aim was to assess the availability of mineral nitrogen for microorganisms in cyanobacterial mats in James Ross Island. The nitrate and ammonium ions in water environment were determined as well as the contents of major elements (C, N, P, S, Na, K, Ca, Mg, Al, Fe, Mn) in cyanobacterial mats. The molar ratios of C:N, C:P and N:P in mats were in focus. The growth of freshwater autotrophs seems not to be limited by the level of nitrogen, according to the content of available mineral nitrogen in water and the biogeochemical stoichiometry of C:N:P. The source of nutrients in the Ulu Peninsula is not obvious. The nitrogen fixation could enhance the nitrogen content in mats, which was observed in some samples containing the Nostoc sp.
Remains referred to Phorusrhacidae from the Cretaceous and Paleogene of the Antarctic Peninsula, and mainly known through informal and succinct descriptions, are reassigned here to other bird lineages recorded in the Antarctic continent. New records of ratites, pelagornithid birds, and penguins are added to the Upper Eocene avifauna of Seymour Island. Moreover, the original allocation for an alleged cursorial seriema−like bird from the Maastrichtian of Vega Island is refuted, and its affinities with foot−propelled diving birds are indicated. The indeterminate Pelagornithidae specimen represents the largest pseudo−toothed bird known so far. It is concluded that there is no empirical evidence for the presence of terror birds in Antarctica.
Many Antarctic marine benthic invertebrates are adapted to specific environ− mental conditions (e.g. low stable temperatures, high salinity and oxygen content). Changes caused by global climatic shifts can be expected to have significant impact on their physiol− ogy and distribution. Odontaster validus, an ubiquitous, omnivorous sea star is one of the “keystone species” in the Antarctic benthic communities. Laboratory experiments were car− ried out to study the effect of temperature rise (from 0 to 5#2;C) on some vital biological func− tions that sea stars must perform in order to survive in their environment. Parameters such as behavioural reaction of sea stars to food and food odour, locomotory performance and abil− ity to right were measured. Temperature increase significantly impaired the ability of O. validus to perform these functions (e.g. lowering the number of sea stars able to right, in− creasing time−to−right, reducing locomotory activity, weakening chemosensory reaction to food and food odour). At temperatures of 4 and 5#2;C a loss of motor coordination was ob− served, although at all tested temperatures up to 5#2;C there were single individuals perform− ing successfully.
Henryk Arctowski Station, the research station of the Polish Academy of Science in Admiralty Bay, King George Island, West Antarctica, is one of the most heavily visited bases in Antarctica. Between the seasons 1991/92 and 1996/97, 12884 tourists were recorded. A specially designed tourist trail was marked to divert visitors toward alternative attractions, not only the station buildings. Tourist management goals include: environmental protection, minimising waste and pollution, respecting the rules relating to protected areas, and prohibition of collections and souveniring.
The paper provides information on oceanobiological expeditions to the Antarctic organized by Polish Academy of Sciences. The scope of research of five expeditions is described and main achievements of Polish Antarctic studies are summarized.
The influence of Lindane on net phytoplankton (mainly diatoms) in samples of waters from the Antarctic was investigated for 24 hours from the introduction of ɣ HCH 0,02 and 2 ppm into the environment. Changes in intensity of 14C incorporation in the light and in rate of release of 14C by the cells in the dark during consecutive light/dark periods were measured. The effect of two different Lindane concentrations in diatoms occurred 16 hours after introduction of the compound into the environment and was independent of concentration. The effect was manifested by delayed induction of photosynthesis following the dark period and also by changes in dynamic equilibrium between carbon assimilation and dissimilation. The presence of Lindane clearly stimulated 14C incorporation in the light and also enhanced the participation of 14C incorporation in overall CO2 exchange in the dark.
In 1989/90, in the region of SSSI 8 situated on King George Island 21 bird species were observed, 12 species were breeding. Dominants were 3 Pygoscelis species (19229 pairs). Five species of pinnipedians were noticed. Mirounga leonina was most abundant in January (623 individuals), Arctocephalus gazella — in February and March (890 individuals), Hydrurga leptonyx in October (39 individuals). The abundance of Leptonychotes weddelli was low and rather stable. As a result of mild winter during the study period such birds as Sterna vittata and Pygoscelis adeliae stayed near their breeding places. The scarcity of Lobodon carcinophagus was probably also a result of this mild winter.
Materials used in this work were collected during BIOM ASS - SIBEX project in the Drake Passage and the Bransfield Strait (1983/1984) in three water layers: 0 - 100 m, 100 — 300 m and 300—500 m. Four species of Chaetognatha were found: Eukrohnia hamata and Sagitta gazellae in both water regions; Sagitta planctonis occurred mainly in the Drake Passage whereas Sagitta marri was noted in the Bransfield Strait and adjacent parts of the Bellingshausen and Scotia seas. Chaetognatha were most numerous in the Drake Passage and generally in the layer 100 — 300 m. Vertical distribution of Chaetognatha was clearly influenced hydrological conditions.
The article provides a general overview of environmental protection and conservation practice in the Antarctic Treaty area, with special reference to the stipulations of the 1991 Protocol on Environmental Protection and its Annexes.
The pinnipeds were counted on the western shore of Admiralty Bay during 1994. It was found that the numbers of one breeding species Mirounga leonina is stable, the remaining four species show a variable pattern of occurrence. However, there is no evidence to detect any trend since 1988.
The material discussed in this paper was collected in the Drake Passage and Bransfield Strait (Antarctica) within the framework of the BIOMASS-SIBEX programme. Samples were collected by hauling Nansen nets verticaly through the 100 — 0, 300—100 and 500 — 300 m layers in December 1983 and January 1984. Of the six species recorded — Metaconchoecia isocheira, Alacia hettacra, Alacia belgicae, Metaconchoecia skogsbergi, Boroecia antipoda and Discoconchoecia off. elegans — the first three, endemic to Antarctic waters — were predominant (92.9%). Ostracoda were found most abundantly in the eastern part of the study area — between Elephant Island and South Orkney Islands, and in the south-western part of Bransfield Strait. Their vertical distribution depended on the hydrological conditions. Ostracoda were most numerous in the 500—300 m and 300 — 100 m layers; very few were recorded in the 100—0 m surface layer.
Although the Antarctic has avoided the worst effects of alien species, its future seems endangered due to increasing natural and man-made pressures. Rapid changes in three major environmental variables have occurred in the Antarctic region during the last decades. In the short term terrestrial biota are likely to benefit from reduced environmental stresses, but in the long run the colonization of the region by lower latitude species with greater competitive ability will become increasingly important and can lead to large-scale changes in biological composition and trophic complexity in some existing Antarctic terrestrial ecosystems. Moreover, the recent dynamic climate changes combined with human activities in the Antarctic region might modify the status of several alien species which have hitherto been considered transient or persistent and could, therefore, become naturalized and threaten the native communities on a larger scale than today, or influence the status of naturalized species.
The authors describe the scope of Polish studies in the field of biology and ecology carried on during 20 years of activity of Polish Antarctic Station. Principal results are briefly summarized and ample literature is presented.
The paper presents the results of seven-year survey of Antarctic seals along the western shore of Admiralty Bay, King George Island, South Shetland Islands. Five species were monitored during seven of the eight years, between 1988-95, excluding 1993. Numbers of elephant seals and Antarctic fur seals showed strong annual cycles, fur seals with two seasonal peaks. These of the other three species were more irregular. Fewer Weddell seals were seen in 1994 and 1995 then during the period 1988-92; with this exception, no overall trend in numbers was apparent during the period 1988-95.
Alongside the purely scientific nature and the first wintering in Antarctica, another innovative feature of the Belgica expedition was its multinational composition. Two, out of its seven persons strong scientific staff, were Polish - H. Arctowski and A. B. Dobrowolski. The first served as scientific deputy-leader of the expedition, the other as laboratory assistant and meteorologist. Their contribution to the scientific success of the Belgian Antarctic Expedition outlined in the present paper, turned into the starting point of brilliant academic careers in the native country and at international level. Both, Arctowski and Dobrowolski, were acknowledged as symbols of the Polish explorations and scientific investigations in polar regions.
The paper presents a catalogue, with description, detailed map location and references to first publications, of new place names introduced mainly during the Polish Geodynamic Expeditions to West Antarctica, 1984-1991. In the South Shetland Islands, new place names were introduced in parts of King George Island and Deception Island (Some new names for Admiralty Bay, King George Island and Penguin Island, introduced prior to 1984 but not yet formally described, are also included here). In Antarctic Peninsula, new place names have been introduced at Hope Bay (Trinity Peninsula), Arctowski Peninsula-Andvord Bay (Danco Coast/Gerlache Strait) and Paradise Harbour (Danco Coast).
The rocks exposed along the western coast of Arctowski Peninsula and on offshore islands, Danco Coast (West Antarctica), represent the following lithostratigraphic units: the Trinity Peninsula Group metasediments (?Permian-Triassic); the Antarctic Peninsula Volcanic Group lavas, agglomerates and tuffs (Lower Cretaceous); the Andean Intrusive Suite, including adamellite, granite, granodiorite, diorite, tonalite and gabbro plutons (mid-Cretaceous), moreover basic and acid hypabyssal dykes (?Upper Cretaceous). The relationships between these rock-units are shown in geological map and sketches of field exposures.
Epifaunal organisms (bryozoans, foraminifera, serpulid polychaetes, cirripeds, octocorals), scratch marks and borings (brachiopod pedicle attachment traces and gastropod, phoronid, sponge and algal boreholes) were recognized on the brachiopod shells from the Eocene La Meseta Formation of Seymour Island, Antarctic Peninsula. They are rare and occur only on about 10% of shells. It is probable that environmental conditions were not suitable for epibionts whose requirements were to be higher than those of brachiopods. The rarity of epifauna on the dead shells can be explained by their rapid burial.
The length of crystalline cones (cc) is proportional to krill body length and this proportion can be described by the equation L cc = L krill x 1.679 + 52.032 ( cc — μm; L krill - mm). By measuring cc one can determine the size of krill with the precision of 2—3 mm. The structure of crystalline cones is not crystal, and the elemental composition includes much of S and Ca. Crystalline cones are often found in the stomach and feces of animals feeding on krill.
Moulting southern elephant seals, Mirounga leonina (L.), were counted in 17 discrete wallows at Walker Bay on Livingston Island in the South Shetland Islands between 2 January and 16 February 1994. Daily weather conditions were also recorded. It was also found that, although there were no overall correlations between wind scale, air temperature, sunshine, precipitation, sea roughness and cloud cover with seal numbers, there were conditions on specific days that affected the movements of seals between wallows. Most notably, it was found that numbers of seals decreased when they were exposed to winds, and that they often sought out more sheltered sites nearby.
Bowseria arctowskii gen. et sp. nov., a new organic-walled monothalamous (single-chamber) foraminiferan is described from samples collected in Admiralty Bay (King George Island, West Antarctica) at 100- 200 m water-depth (mwd). The species is characterized by a large (1- 2 mm) elongate theca with a single terminal aperture. Molecular phylogenetic analyses, based on partial small subunit rDNA sequences, indicate that the new species belong to a clade of single-chambered foraminifers that branch as a sister group to the multi-chambered textulariids and rotaliids. The most closely related to the new species is an undetermined allogromiid from under the Ross Ice Shelf.
Adamussium jonkersi sp. nov. is described from the Late Oligocene Destruction Bay Formation, Wrona Buttress area, King George Island (South Shetlands), West Antarctica. The unit, characterized by volcanic sandstone, is a shallow marine succession deposited in a moderate- to high-energy environment. The thin-shelled pectinids, collected from the lower part of the unit, are preserved mostly as complete valves. Shell thickness, sculpture pattern and umbonal angle suggest a free-living, inactive swimming life habit.
Lichens of relict penguin colonies and sites affected by active penguin colonies were investigated in Victoria Land, Ross Sea sector, continental Antarctica. A total of 17 coastal sites, seven in northern and ten in southern Victoria Land, have been investigated across 7 ° of latitude from 71 ° to 78 ° S. Altogether 40 taxa of lichens have been identified. Four of the recorded species are new to the Antarctic – Caloplaca erecta , C. soropelta , C. tominii and Physcia tenella ; two species are new to the Victoria Land area – Lecania nylanderiana and Lecanora polytropa . The first lichen records from Beaufort Island are also provided. Data presented here expand the knowledge on the occurrence, diversity and distribution of Victoria Land lichens.
The tarsometatarsus, a compound bone from the lower leg in birds, is the most important skeletal element in fossil penguin taxonomy, especially in the case of early members of this group. However, any attempt to go beyond the problem of mere classification obviously requires the better understanding of osteological traits under consideration. This in turn touches on the issue of interplay between bone and concomitant soft−tissue structures, such as muscles, tendons and vessels. This paper focuses on the more holistic comprehension of the tarsometatarsal section of the Eocene penguin foot, based on the analysis of the myology and the vascular system of its modern counterparts. A number of graphical reconstructions are provided with a discussion of the role of the hypotarsus and inter− metatarsal foramina.