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Number of results: 217
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Abstract

An additional account on the Oligocene cyclostome Bryozoa has been made from the glaciomarine sediments of the Low Head Member (= Pecten conglomerate of Barton 1965) of the Polonez Cove Formation on King George Island (South Shetland Island, West Antarctica). The following genera have been recognized for the first time in Paleogene of Antarctica: Crista, Bicrisia, Exidmonea, Filisparsa and Mecynoecia. Paleoecological interpretation of the bryozoan assemblage implies that the fauna lived in shallow water at a depth of around 50 m.
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Abstract

Solitary corals of the genus Flabellum are described from the Lower Oligocene glaciomarine strata of the Polonez Cove Formation of King George Island, West Antarctica. This is the oldest record of the genus from Antarctica.
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Abstract

Flying bird counts were carried out at Esperanza Bay (62°24'S, 56°59'W), Antarctic Peninsula, between November 1989 and February 1990. Six breeding species (Oceanites oceanicus, Chionis alba, Catharacta lonnbergi, Catharacta maccormicki, Larus dominicanus and Sterna vittata) and six visitor species (Macronectes giganteus, Fulmarus glacialoides, Daption capense, Pagodroma nivea, Fregetta tropica and Phalacrocorax atriceps) were recorded. Kelp gull and Antarctic tern populations have decreased in relation to the data by previous authors, perhaps as a result of the increased activity at Esperanza Station. Cygnus melanocoryphus was recorded for the first time at Esperanza Bay.
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Abstract

Upper Cretaceous calcareous nannoplankton recycled into the Pliocene Pecten Conglomerate of Cockburn Island (Antarctic Peninsula) provide a paleontological record of Upper Cretaceous sedimentary sequences in the James Ross Basin. The calcareous nannofossil assemblage comprises nearly 40 taxa and is dominated by Campanian-Maestrichtian species. The investigated assemblage shares some features with the southern high-latitude contemporaneous calcareous nannofossil assemblages from outcrops on adjacent Seymour (Marambio) Island and many with deep-sea drilling sites in the circum-Antarctic region.
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Abstract

The present paper contains a list of 104 taxa of lichens and lichenicolous fungi, found in the Cape Lions Rump, Site of Special Scientific Interest No. 34 (King George Island, Antarctica), with their distribution and ecological analysis. A provisional vegetation map of the area is also provided. During the field survey the data were collected using the cartogram method in a grid of squares 250 x 250 m. The current abundance and spatial distribution of lichen species provides baseline data for long-term monitoring biological changes.
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Abstract

Skeletal remains of penguins from the Eocene La Meseta Formation (Seymour Island, Antarctica) constitute the only extensive fossil record of Antarctic Sphenisciformes. No articulated skeletons are known, and almost all fossils occur as single isolated elements. Most of the named species are based on tarsometatarsi (for which the taxonomy was revised in 2002). Here, 694 bones (from the Polish collection) other than tarsometatarsi are reviewed, and allocated to species. They confirm previous conclusions and suggest that ten species grouped in six genera are a minimal reliable estimate of the Eocene Antarctic penguin diversity. The species are: Anthropornis grandis, A. nordenskjoeldi, Archaeospheniscus wimani, Delphinornis arctowskii, D. gracilis, D. larseni, Marambiornis exilis, Mesetaornis polaris, Palaeeudyptes gunnari and P. klekowskii. Moreover, diagnoses of four genera (Anthropornis, Archaeospheniscus, Delphinornis and Palaeeudyptes) and two species (P. gunnari and P. klekowskii) are supplemented with additional, non-tarsometatarsal features. Four species of the smallest penguins from the La Meseta Formation (D. arctowskii, D. gracilis, M. exilis and M. polaris) seem to be the youngest taxa within the studied assemblage - their remains come exclusively from the uppermost unit of the formation. All ten recognized species may have co-existed in the Antarctic Peninsula region during the Late Eocene epoch.
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Abstract

Trematomus newnesi (Nototheniidae), a bentho-pelagic fish, caught off Adélie Land (eastern Antarctic) was examined for the presence of internal parasitic worms. These fishes were infected with 11 species and larval forms of parasites: Digenea (Macvicaria pennelli, Neolebouria terranovaensis, Genolinea bowersi, and Elytrophalloides oatesi), larval Cestoda (two forms of tetraphyllidean metacestodes, bilocular form and trilocular form, and diphyllobothriid plerocercoids), Acanthocephala (Metacanthocephalus campbelli, M. johnstoni) and larval Nematoda (Contracaecum osculatum, C. radiatum). Larval cestodes were the dominant parasites, whereas acanthocephalans were relatively rare. Five species and larval forms were recorded also in fish caught in the Davis Sea. A check list of parasites of T. newnesi recorded in the eastern- and western Antarctic comprises 21 species and larval forms. Probably, T. newnesi plays an important role in life cycles of parasitic worms in the Antarctic.
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Abstract

A sediment core (LS-1) collected from Long Lake in King George Island, South Shetland Islands (West Antarctica) was analyzed for a variety of textural, geochemical, isotopic and paleontological properties together with 14C age dates. These data combined with published records of other studies provide a detailed history of local/regional postglacial paleoproductivity variation with respect to terrestrial paleoclimate change. The lithologic contrast of a lower diamicton and an upper fine-grained sediment demonstrates glacial recession and subsequent lake formation. The upper fine-grained deposit, intercalated by mid-Holocene tephra-fallout followed by a tephra gravity flow, was formed in a lacustrine environment. Low total organic carbon (TOC) and biogenic silica (Sibio) contents with high C/N ratios characterize the diamicton, whereas an increase of TOC and Sibio contents characterize the postglacial lacustrine fine-grained sediments, which are dated at c. 4000 yrBP. More notable are the distinct TOC maxima, which may imply enhanced primary productivity during warm periods. Changes in Sibio content and δ13C values, which support the increasing paleoproductivity, are in sympathy with these organic matter variations. The uniform and low TOC contents that are decoupled by Sibio contents are attributed to the tephra gravity flows during the evolution of the lake rather than a reduced paleoproductivity. A very recent TOC maximum is also characterized by high Sibio content and δ13C values, clearly indicating increased paleoproductivity consequent upon gradual warming across King George Island . Comparable with changes in sediment geochemistry, the occurrence and abundance of several diatom species corroborate the paleoproductivity variations together with the lithologic development. However, the paleoclimatic signature in local terrestrial lake environment during the postglacial period (for example the Long Lake) seems to be less distinct, as compared to the marine environment.
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Abstract

Penguin bones from the La Meseta Formation (Seymour Island, Antarctic Peninsula) are the only record of Eocene Antarctic Sphenisciformes. Being an abundant component of the youngest unit of the formation (Telm7), they are not so common in earlier strata. Here, I present the oldest penguin remains from the La Meseta Formation (Telm1-Telm2), often bearing close resemblance to their counterparts from younger units. Addressing the recent findings in fossil penguin systematics, I suggest there is too weak a basis for erecting new Eocene Antarctic taxa based on non-tarsometatarsal elements of penguin skeletons, and considering Oligocene species part of the studied assemblage. Finally, I conclude if the common ancestor of extant Sphenisciformes lived in the Eocene Antarctic (as suggested recently), penguins referred to Delphinornis seem to be prime candidates to that position.
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Abstract

Campylobacter is one of the most common bacterial causes of diarrheal illness in humans. This study describes the isolation of Campylobacter lari from seabirds during 4 consecutive summers (2000-2003) in Hope Bay, Antarctic Peninsula. One hundred and twenty-two spontaneously dead Antarctic seabirds were studied. Ten Campylobacter lari isolates from 7 skuas (Stercorarius spp.), 2 kelp gulls (Larus dominicanus), and 1 Adelie penguin (Pygoscelis adeliae) were identified by phenotypical characteristics. Human activity in Antarctica was identified as a possible source of infectious agents, and migratory birds could be carriers of infectious diseases. However, nothing is known about zoonotic enteropathogens causing diseases in humans living in the Antarctic region. We demonstrated that seabirds carried C. lari in their intestines, and that they were settled around the lakes where humans are supplied with fresh water. Consumption of fresh water from Antarctic lakes contaminated with feces of seabirds could be a risk of human campylobacteriosis. This is the first report of C. lari isolated from seabirds in Hope Bay, Antarctica.
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Abstract

In total, 18 species and larval forms of endoparasitic worms were found in 19 newly examined notothenioid fishes of three species, Trematomus hansom, Notothenia coriiceps and Chionodraco hamatus, caught off Adelie Land. One digenean species, Neolepidapedon trema-tomi, was recorded in this area for the first time. A total list of endoparasitic worms prepared by Zdzitowiecki etal. (1998) increased from 20 to 21 species and larval forms and concerns 11 deter­mined and one determined species of Digenea (the most diverse group), three larval forms of Cestoda, three species (one identified only to genus) of Acanthocephala, two species (one in the larval stage) and one larval form of Nematoda. All these species and forms, with the exception of the indetcrmined digenean, occur also in the deep Antarctica, in the Ross Sea and/or in the Weddell Sea. The prevalence and relative density of infection with each parasite in three host species is given based on summarized previous and new data.
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Abstract

Measurements were made of organic fluxes at a coastal sediment at Signy Island , South Orkney Islands, Antarctica , between December 1990 and March 1992. The deposition rate of organic matter to the sediment was measured at the same time with a maximum sedimentation rate of 306 mg C m–2 d–1. The rates of sedimentary organic input were small during winter ice cover, and the organic content of the sediment declined during this period as available organic matter was depleted. Fresh organic input occurred as soon as the sea-ice melted and ice algal biomass was deposited to the sediment; and was sustained during the spring after ice break-up by continued primary production in the water column. The proportion of available carbon in surface sediments was measured during a seasonal cycle using Pseudomonas aeruginosa as an indicator organism over the 0–1 cm depth horizon. Variations in the amount of organic matter deposited to the sediments and the proportion of available carbon were observed during the seasonal cycle. Seasonal variations of benthic activity in this coastal sediment was regulated by the input and availability of organic matter, and not by seasonal water temperature, which was relatively constant between –1.8 and 0.5°C .
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Abstract

The paper presents the results of taxonomical investigation of the genus Cladonia Hill ex P. Browne from King George Island . Individuals belonging to this lichen genus were studied using methods of classical herbarium taxonomy supported by chemical analysis. Fourteen species have been recognized in the study area, with C. asahinae J.W. Thomson being reported from King George Island for the first time, and C. cervicornis subsp. mawsonii reported as new for the South Shetland Islands. The occurrence of C. cariosa is confirmed for the Antarctic region. The diagnostic characters, ecology and important remarks referring to particular species are briefly presented. An updated key for identification of the species from King George Island and neighbouring islands of South Shetlands is included.
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Abstract

The marine psychrophilic and endemic Antarctic yeast Leucosporidium antarcticum strain 171 synthesizes intracellular b-fructofuranosidase, and intra- and extracellular a-glucosidases. Each enzyme is maximally produced at 5°C , while the strain’s optimum growth temperature is 15°C . Invertase biosynthesis appeared regulated by catabolic repression, and induced by sucrose; the enzyme was extremely unstable ex vivo, and only EDTA, Mn2+, and BSA stabilized it for up to 12 h after yeast cell lysis. Thermal stability of the invertase was also low (30 min at temperatures up to 12°C). The optimum temperature for invertase activity was 30°C , and optimum pH was 4.55 to 4.75. The extracellular a-glucosidase was maximally active at 35°C and pH 6.70–7.50, and stable for 30 min up to 20°C.
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Abstract

Drilling operations of the Cape Roberts Project took place between 1997 and 1999 offshore of Cape Roberts in the western Ross Sea, Antarctica. These were made possible due to a group effort by geoscientists from Australia, Germany, Italy, New Zealand, Great Britain, and the United States. The major goal of this undertaking was the recovery and analysis of sediment core, which was expected to provide a first East Antarctic record of the Early Cenozoic hothouse to icehouse climatic transition. This goal was not attained. Nevertheless, over the three seasons, a 1500 m long composite section was recovered, including a predominantly Early Oligocene to Early Miocene (34—17 Ma) glaciomarine succession. It was analyzed in terms of sediment physical properties, paleontology, tectonic structures and geophysics. This multidisciplinary investigation allowed detailed reconstruction of a significant portion of local environmental history, spanning a period of highly variable environmental conditions strongly affected by local glacier advance and retreat across the Victoria Land Basin margin.
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Abstract

This paper presents some preliminary data on the quantitative distribution of Tanaidacea in Admiralty Bay, mainly in its Ezcurra Inlet. On the soft bottom of this inlet, and especially its small glacial lagoon, Herve Cove, the highest abundance but the lowest species richness of Tanaidacea was found. In the central basin of Admiralty Bay, much higher species richness was observed along with much lower tanaid abundance.
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Abstract

Objects that have come within the inventory are the effect of whaling activity car­ried out in the region of South Shetland Islands in the first half of the twentieth century. They in­clude mainly bones of hunted animals, rarely wooden or metal objects, part of which may be re­lated to the whaling industry. In this paper the areas of particular accumulation of these objects have been determined, and the attempts to explain the reasons for such accumulations have been made. In addition, certain suggestions for further investigations into whaling activity in the South Shetland Islands region have been put forward. During the work 158 large fragments of whale skulls, among others, have been inventoried. The total number of individuals whose pre­served relics have been explored within the surveyed sections of the Admiralty Bay shores has been estimated to be 210-230.
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Abstract

Eocene penguin remains from Seymour Island (Antarctica) are so far the oldest−known record of extinct Sphenisciformes. Rich Argentineand Polish collections of penguin bones from the La Meseta Formation are taxonomically revised on tarsometatarsal morphology. Two genera and four species are erected: Mesetaornis polarisgen. et sp. n., Marambiornis exilisgen. et sp. n., Delphinornis arctowskiisp. n. and D. gracilissp. n. Moreover, the diagnoses of already described species: Anthropornis nordenskjoeldi, A. grandis, Palaeeudyptes klekowskii, P. gunnari, Archaeospheniscus wimani and Delphinornis larseniare revised as well. Gradual cooling of climate, changes of environment andtrophic relationships, that lasted several millions years, were most probably responsible forthe intense speciation and taxonomic diversification of the Middle–Late Eocene La Meseta penguins.
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Abstract

Brachiopods are reported for the first time from the Lower Miocene Cape Melville Formation of King George Island, South Shetland Islands, West Antarctica. Two genera, Liothyrella Thomson and Paraldingia Richardson have been identified. This is the first occurrence of Paraldingia in Antarctica.
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Abstract

A few specimens of a macroporid bryozoan were collected, from the Eocene La Meseta Formation from Seymour (Marambio) Island, Antarctic Peninsula. Based on the morphology of the studied specimens Macropora antarctica sp.n. has been erected. This is the stratigraphically oldest species of the genus which exhibits a number of similarities with the Tertiary fossils and some Recent macroporids reported from the Southern Hemisphere i.e., Australia, New Zealand and South America.
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Abstract

The occurrence of coreless winters in the South Shetland Islands region is related to increase in the intensity of cyclonic circulation and to the presence of massive and rapid advection of warm air northerly and westerly. Coreless winter developments depend on large-scale oceanic processes – the presence of positive anomalies in sea surface temperature (SST) in the Bellingshausen Sea over the range 080°–092°W and the retreat of sea ice extent southwards. When negative anomalies of SST in the same region are observed and the sea ice extent advances northwards, a winter with clearly marked cold core is experienced at the Arctowski Station on the South Shetlands.
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Abstract

Molluscan fossils accompanied by familiar SSF have been recovered from Early Cambrian limestone erratics in the Early Miocene glaciomarine Cape Melville Formation of King George Island, West Antarctica. The molluscan fauna comprises the hyoliths Conotheca, Microcornus, Parkula, Hyptiotheca, “Hyolithes”, the helcionelloids ?Pararacornus, Yochelcionella, Anabarella, the low dextrally coiled Pelagiella and the high helically coiled Beshtashella, as well as the problematic mollusc Cupitheca. Most of described species are recorded here for the first time from Antarctica. The lithological and fossil contents of the erratics are almost the same as from autochthonous successions the Shackleton Limestone in the Argentina Range and Transantarctic Mountains. Early Cambrian outcrops around the Weddell Sea are a probable source of the erratic boulders. The Antarctic fauna is very similar to that from uppermost Botomian and Toyonian carbonate deposits in the Cambrian Basins of South Australia. These faunal and facies similarities between Antarctica and Australia confirm their neighbouring position and common biotic and basin evolution on the Cambrian Gondwana margin.
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Abstract

The infections of four fish species, Trematomus newnesi, T. bernacchii, Lindbergichthys nudifrons and Harpagifer antarcticus with parasitic worms, in the coastal zone off the Vernadsky Station (Argentine Islands, West Antarctica) are described. Data on infections are compared with previous results from Admiralty Bay at the South Shetland Islands. Indices of infection are for each host-parasite relationship. In total, 16 taxa of parasites were recorded: 6 digeneans, 3 larval cestodes, 4 (adult and cystacanth) acanthocephalans, and 3 (adult and larval) nematodes. Fifteen of them have been previously recorded in Notothenia coriiceps from this area. Hence, the number of parasitic taxa recorded in this region increased from 21 to 22. Either the digenean Macvicaria georgiana or acanthocephalan Corynosoma pseudohamanni were dominants in different hosts. Trematomus bernacchii was the most strongly infected, especially with M. georgiana (prevalence 100%, mean abundance 113.7). The infection parameters of the majority of parasites were lower at the Vernadsky Station than in the Admiralty Bay, especially for host-parasite relations with larval cestodes and nematodes. The presently reported study have confirmed that the southern range of distribution of two acanthocephalans, Aspersentis megarhynchus and Corynosoma hamanni extends south to the area near the Argentine Islands.
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Abstract

On the basis of the distinctly biplicate and carinate leaves in the distal portion Grimmia lawiana J.H. Willis, the only continental Antarctic endemic moss species, is transferred to the genus Coscinodon Spreng. and the new combination C. lawianus (J.H. Willis) Ochyra is proposed. The species is described and illustrated, its affinities are discussed and its geographical distribution in the Antarctic is mapped. Grimmia reflexidens Müll. Hal., a southern South American endemic species from Chile , is briefly assessed and this species is also shifted to Coscinodon as C. reflexidens (Müll. Hal.) Ochyra, comb. nov. A key to all species of the genus Coscinodon is presented. Guembelia longirostris (Hook.) Ochyra et Żarnowiec is reported for the first time from the Antarctic on the basis of a specimen collected from the Nordenskjöld Coast on the eastern coast of the Antarctic Peninsula.
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Abstract

The cephalopod diet of the gentoo penguin, Pygoscelis papua and the Antarctic fur seal, Arctocephalus gazella was comparatively analyzed at Laurie Island, South Orkney Islands. A total of 125 stomach samples were collected by the water off-loading method from gentoo penguins during the autumns of 1993, 1995 and 1996, and 39 fur seal scats were collected from mid March to April 1988. Cephalopods preyed upon by gentoo penguins were represented by 1974 beaks (1628 lower, 346 upper) which occurred in 50.4% of the samples. Lower beaks identified belonged exclusively to the squid Psychroteuthis glacialis. The mean lower rostral length (LRL) of these beaks was 1.1 mm (range 0.4– 1.8 mm). From the Antarctic fur seal scats 103 beaks (41 lower, 62 upper) were removed from 60.6% of scats which contained prey remains. The cephalopod species identified were Slosarczykovia circumantarctica and P. glacialis which constituted 78.8% and 21.1% in terms of numbers, respectively. The mean lower rostral length for S. circumantarctica was 2.7 mm (range 2.0–3.5 mm), while that of P. glacialis was 1.6 mm (range 1.0–2.5 mm). The foraging behaviour of the two top predators was analyzed and discussed according to the composition and size of their cephalopod prey.
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