Science.gov

Sample records for antarctic birds neornithes

  1. [Stable morphologies and mosaicism in the macroevolution of birds (Neornithes)].

    PubMed

    Zelenkov, N V

    2015-01-01

    Modern orders of Neornithine birds are separated by distinct morphological gaps, hampering the development of particular models. of macroevolutionary transformations. However, recent decades have witnessed the discovery and extensive study of many fossil groups of birds, which shed light on the origin of modern higher taxa. These fossils further allow analyzing the whole process of the macroevolutionary change in this group of vertebrates during the Cenozoic. Here, a brief review is presented of the "transitional" taxa with special attention to representative of the clade Galloanseres. Almost all transitional groups of fossil birds do display mosaic morphology. It is noted that many stable morphologies (characters and character complexes) persist in different groups, occurring either as primitive states, or as advanced ones. The stable recurrence of these characters is caused by the persistence of stable ontogenetic pathways. On the other hand, independent evolution of various morphologies can be explained by the modular organization of the development. The modularity in the structure of the foot is used here as an example to show a possible way of the origin of the foot in extant perching birds (Passeriformes). The mosaic morphology of the transitional taxa is seen as the only possible way to overcome the evolutionary constraint of the parallel optimization of numerous organismal systems. It is noted that in course of macroevolutionary change, no complete filling of morphological gaps occur. Transitional forms are separated by additional gaps from their ancestors and descendants. Hence, stem groups are seen as the most probable ancestors of crown taxa. It is further noted that the evolutionary formation of some higher taxa of the living birds was initiated by the evolution of advanced morphology of the feeding apparatus and skull, while change in their. postcranial morphology was delayed. PMID:26353395

  2. Higher-order phylogeny of modern birds (Theropoda, Aves: Neornithes) based on comparative anatomy. II. Analysis and discussion

    PubMed Central

    LIVEZEY, BRADLEY C; ZUSI, RICHARD L

    2007-01-01

    In recent years, avian systematics has been characterized by a diminished reliance on morphological cladistics of modern taxa, intensive palaeornithogical research stimulated by new discoveries and an inundation by analyses based on DNA sequences. Unfortunately, in contrast to significant insights into basal origins, the broad picture of neornithine phylogeny remains largely unresolved. Morphological studies have emphasized characters of use in palaeontological contexts. Molecular studies, following disillusionment with the pioneering, but non-cladistic, work of Sibley and Ahlquist, have differed markedly from each other and from morphological works in both methods and findings. Consequently, at the turn of the millennium, points of robust agreement among schools concerning higher-order neornithine phylogeny have been limited to the two basalmost and several mid-level, primary groups. This paper describes a phylogenetic (cladistic) analysis of 150 taxa of Neornithes, including exemplars from all non-passeriform families, and subordinal representatives of Passeriformes. Thirty-five outgroup taxa encompassing Crocodylia, predominately theropod Dinosauria, and selected Mesozoic birds were used to root the trees. Based on study of specimens and the literature, 2954 morphological characters were defined; these characters have been described in a companion work, approximately one-third of which were multistate (i.e. comprised at least three states), and states within more than one-half of these multistate characters were ordered for analysis. Complete heuristic searches using 10 000 random-addition replicates recovered a total solution set of 97 well-resolved, most-parsimonious trees (MPTs). The set of MPTs was confirmed by an expanded heuristic search based on 10 000 random-addition replicates and a full ratchet-augmented exploration to ascertain global optima. A strict consensus tree of MPTs included only six trichotomies, i.e. nodes differing topologically among MPTs

  3. Higher-order phylogeny of modern birds (Theropoda, Aves: Neornithes) based on comparative anatomy. II. Analysis and discussion.

    PubMed

    Livezey, Bradley C; Zusi, Richard L

    2007-01-01

    In recent years, avian systematics has been characterized by a diminished reliance on morphological cladistics of modern taxa, intensive palaeornithogical research stimulated by new discoveries and an inundation by analyses based on DNA sequences. Unfortunately, in contrast to significant insights into basal origins, the broad picture of neornithine phylogeny remains largely unresolved. Morphological studies have emphasized characters of use in palaeontological contexts. Molecular studies, following disillusionment with the pioneering, but non-cladistic, work of Sibley and Ahlquist, have differed markedly from each other and from morphological works in both methods and findings. Consequently, at the turn of the millennium, points of robust agreement among schools concerning higher-order neornithine phylogeny have been limited to the two basalmost and several mid-level, primary groups. This paper describes a phylogenetic (cladistic) analysis of 150 taxa of Neornithes, including exemplars from all non-passeriform families, and subordinal representatives of Passeriformes. Thirty-five outgroup taxa encompassing Crocodylia, predominately theropod Dinosauria, and selected Mesozoic birds were used to root the trees. Based on study of specimens and the literature, 2954 morphological characters were defined; these characters have been described in a companion work, approximately one-third of which were multistate (i.e. comprised at least three states), and states within more than one-half of these multistate characters were ordered for analysis. Complete heuristic searches using 10 000 random-addition replicates recovered a total solution set of 97 well-resolved, most-parsimonious trees (MPTs). The set of MPTs was confirmed by an expanded heuristic search based on 10 000 random-addition replicates and a full ratchet-augmented exploration to ascertain global optima. A strict consensus tree of MPTs included only six trichotomies, i.e. nodes differing topologically among MPTs

  4. Climate Change Influences on Antarctic Bird Populations

    NASA Astrophysics Data System (ADS)

    Korczak-Abshire, Małgorzata

    2010-01-01

    Rapid changes in the major environmental variables like: temperature, wind and precipitation have occurred in the Antarctic region during the last 50 years. In this very sensitive region, even small changes can potentially lead to major environmental perturbations. Then the climate change poses a new challenge to the survival of Antarctic wildlife. As important bioindicators of changes in the ecosystem seabirds and their response to the climate perturbations have been recorded. Atmospheric warming and consequent changes in sea ice conditions have been hypothesized to differentially affect predator populations due to different predator life-history strategies and substantially altered krill recruitment dynamics.

  5. Entanglement of Antarctic fur seals at Bird Island, South Georgia.

    PubMed

    Waluda, Claire M; Staniland, Iain J

    2013-09-15

    Between November 1989 and March 2013, 1033 Antarctic fur seals Arctocephalus gazella were observed entangled in marine debris at Bird Island, South Georgia. The majority of entanglements involved plastic packaging bands (43%), synthetic line (25%) or fishing net (17%). Juvenile male seals were the most commonly entangled (44%). A piecewise regression analysis showed that a single breakpoint at 1994 gave the best description of inter-annual variability in the data, with higher levels of entanglements prior to 1994 (mean=110±28) followed by persistent lower levels (mean=28±4). Records of entanglements from other sites monitored in the Scotia Sea are also presented. Legislation imposed by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) has, to a certain extent, been effective, but persistent low levels of seal entanglements are still a cause for concern at South Georgia. PMID:23915979

  6. Antibiotic resistance in Escherichia coli strains isolated from Antarctic bird feces, water from inside a wastewater treatment plant, and seawater samples collected in the Antarctic Treaty area

    NASA Astrophysics Data System (ADS)

    Rabbia, Virginia; Bello-Toledo, Helia; Jiménez, Sebastián; Quezada, Mario; Domínguez, Mariana; Vergara, Luis; Gómez-Fuentes, Claudio; Calisto-Ulloa, Nancy; González-Acuña, Daniel; López, Juana; González-Rocha, Gerardo

    2016-06-01

    Antibiotic resistance is a problem of global concern and is frequently associated with human activity. Studying antibiotic resistance in bacteria isolated from pristine environments, such as Antarctica, extends our understanding of these fragile ecosystems. Escherichia coli strains, important fecal indicator bacteria, were isolated on the Fildes Peninsula (which has the strongest human influence in Antarctica), from seawater, bird droppings, and water samples from inside a local wastewater treatment plant. The strains were subjected to molecular typing with pulsed-field gel electrophoresis to determine their genetic relationships, and tested for antibiotic susceptibility with disk diffusion tests for several antibiotic families: β-lactams, quinolones, aminoglycosides, tetracyclines, phenicols, and trimethoprim-sulfonamide. The highest E. coli count in seawater samples was 2400 cfu/100 mL. Only strains isolated from seawater and the wastewater treatment plant showed any genetic relatedness between groups. Strains of both these groups were resistant to β-lactams, aminoglycosides, tetracycline, and trimethoprim-sulfonamide.In contrast, strains from bird feces were susceptible to all the antibiotics tested. We conclude that naturally occurring antibiotic resistance in E. coli strains isolated from Antarctic bird feces is rare and the bacterial antibiotic resistance found in seawater is probably associated with discharged treated wastewater originating from Fildes Peninsula treatment plants.

  7. Corticosterone, prolactin and egg neglect behavior in relation to mercury and legacy POPs in a long-lived Antarctic bird.

    PubMed

    Tartu, S; Angelier, F; Wingfield, J C; Bustamante, P; Labadie, P; Budzinski, H; Weimerskirch, H; Bustnes, J O; Chastel, O

    2015-02-01

    Seabirds often have high loads of contaminants. These contaminants have endocrine disrupting properties but their relationships with some endocrine mechanisms are still poorly investigated in free-living organisms. This is the case for the stress response which shifts energy investment away from reproduction and redirects it towards survival. In birds, this stress response is achieved through a release of corticosterone and is also accompanied by a decrease in circulating prolactin, an anterior pituitary hormone widely involved in regulating parental cares. We measured blood concentrations of some legacy persistent organic pollutants (POPs) and mercury (Hg) and examined their relationships with the corticosterone and prolactin responses of known-age (9-46 years old) incubating snow petrels (Pagodroma nivea) to a standardized capture/handling stress protocol. In this Antarctic seabird, we also investigated whether high contaminant burden correlates with a higher occurrence of egg neglect, a frequently observed behavior in snow petrels. POPs and Hg were unrelated to age. Stress-induced corticosterone concentrations were positively related to POPs in both sexes, and stress-induced prolactin concentrations were negatively related to Hg in males. Egg-neglect behavior was not related to POPs burden, but males with higher Hg concentrations were more likely to neglect their egg. This suggests that in birds, relationships between age and contaminants are complex and that even low to moderate concentrations of POPs and Hg are significantly related to hormonal secretion. In this Antarctic species, exposure to legacy POPs and Hg could make individuals more susceptible to environmental stressors such as ongoing disturbances in Polar Regions. PMID:25461020

  8. Egg shape changes at the theropod-bird transition, and a morphometric study of amniote eggs.

    PubMed

    Deeming, D Charles; Ruta, Marcello

    2014-11-01

    The eggs of amniotes exhibit a remarkable variety of shapes, from spherical to elongate and from symmetrical to asymmetrical. We examine eggshell geometry in a diverse sample of fossil and living amniotes using geometric morphometrics and linear measurements. Our goal is to quantify patterns of morphospace occupation and shape variation in the eggs of recent through to Mesozoic birds (neornithe plus non-neornithe avialans), as well as in eggs attributed to non-avialan theropods. In most amniotes, eggs show significant deviation from sphericity, but departure from symmetry around the equatorial axis is mostly confined to theropods and birds. Mesozoic bird eggs differ significantly from extant bird eggs, but extinct Cenozoic bird eggs do not. This suggests that the range of egg shapes in extant birds had already been attained in the Cenozoic. We conclude with a discussion of possible biological factors imparting variation to egg shapes during their formation in the oviduct. PMID:26064565

  9. A new time tree reveals Earth history’s imprint on the evolution of modern birds

    PubMed Central

    Claramunt, Santiago; Cracraft, Joel

    2015-01-01

    Determining the timing of diversification of modern birds has been difficult. We combined DNA sequences of clock-like genes for most avian families with 130 fossil birds to generate a new time tree for Neornithes and investigated their biogeographic and diversification dynamics. We found that the most recent common ancestor of modern birds inhabited South America around 95 million years ago, but it was not until the Cretaceous-Paleogene transition (66 million years ago) that Neornithes began to diversify rapidly around the world. Birds used two main dispersion routes: reaching the Old World through North America, and reaching Australia and Zealandia through Antarctica. Net diversification rates increased during periods of global cooling, suggesting that fragmentation of tropical biomes stimulated speciation. Thus, we found pervasive evidence that avian evolution has been influenced by plate tectonics and environmental change, two basic features of Earth’s dynamics. PMID:26824065

  10. A new time tree reveals Earth history's imprint on the evolution of modern birds.

    PubMed

    Claramunt, Santiago; Cracraft, Joel

    2015-12-01

    Determining the timing of diversification of modern birds has been difficult. We combined DNA sequences of clock-like genes for most avian families with 130 fossil birds to generate a new time tree for Neornithes and investigated their biogeographic and diversification dynamics. We found that the most recent common ancestor of modern birds inhabited South America around 95 million years ago, but it was not until the Cretaceous-Paleogene transition (66 million years ago) that Neornithes began to diversify rapidly around the world. Birds used two main dispersion routes: reaching the Old World through North America, and reaching Australia and Zealandia through Antarctica. Net diversification rates increased during periods of global cooling, suggesting that fragmentation of tropical biomes stimulated speciation. Thus, we found pervasive evidence that avian evolution has been influenced by plate tectonics and environmental change, two basic features of Earth's dynamics. PMID:26824065

  11. [Jaws of birds].

    PubMed

    Matsuoka, Hiroshige

    2005-05-01

    Birds (Class Aves) have been hypothesized to have evolved from theropod dinosaurs, which belong to the group known as diapsid reptiles, during the Mesozoic era. They subsequently acquired derived characters relating to flying ability in all parts of their body, including the jaws, which were toothed in the ancestral forms but beaked in later members. When the fore limbs became modified as wings specialized for flight, they became incapable of grasping food, which function was then assumed by the avian bill. Avian bills consequently evolved great morphological diversity reflecting very divergent modes of feeding. To illustrate the progression of "the evolution of vertebrate jaws," the comparative osteology of avian cranial bones is exemplified by reference to Mesozoic birds and the morphological and functional variations observed among the bills of Neornithes. PMID:15876751

  12. Antarctic science

    NASA Astrophysics Data System (ADS)

    Summerhayes, Colin

    Once upon a time, dinosaurs roamed Antarctica and swam in its seas. Since then, life evolved as the climate cooled into the ice ages. Life will no doubt continue to evolve there as the globe now warms. But nowadays, humans are having a profound and direct effect on life in Antarctica, the sub-Antarctic islands, and the surrounding Southern Ocean, which are being invaded by a wide range of alien species including microbes, algae, fungi, bryophytes, land plants, invertebrates, fish, birds, and mammals.

  13. Age-Related Mercury Contamination and Relationship with Luteinizing Hormone in a Long-Lived Antarctic Bird

    PubMed Central

    Tartu, Sabrina; Bustamante, Paco; Goutte, Aurélie; Cherel, Yves; Weimerskirch, Henri; Bustnes, Jan Ove; Chastel, Olivier

    2014-01-01

    Seabirds, as long-lived top predators, accumulate contaminants such as mercury (Hg), an established endocrine disruptor. In long lived species hormonal secretion varies with age; therefore, Hg-induced endocrine disruption may be exacerbated in some age classes. Here we investigated relationships between blood total Hg and luteinizing hormone (LH, a key pituitary hormone for the onset of breeding), in pre-laying known-age (11–45 years old) snow petrels (Pagodroma nivea) from Adélie Land, Antarctica. We predicted that 1) blood Hg would increase with advancing age as a consequence of bio-accumulation; and that 2) increasing blood Hg would be related to decreased concentrations of LH in the most Hg-contaminated individuals. Hg concentrations were higher in females than in males (p<0.001), and contrary to our prediction, decreased with advancing age in males (p = 0.009) and tended to do so in females (p = 0.06). The analysis of stable isotopes (δ13C and δ15N) suggested that this unexpected pattern could originate from age and sex-related variations in trophic niche, and hence Hg exposure. Regarding LH, our prediction was only supported in young birds (≤23 years) where baseline LH was inversely correlated with Hg concentrations (p = 0.04). Hg burden did not predict baseline LH or GnRH-induced LH in birds that were more than 23 years old. These results show that age and contaminants may interfere with major endocrine mechanisms and, together with other recent studies, support the view that Hg could be connected to LH secretion and could then impair the fitness of long-lived birds. PMID:25072936

  14. Birds, Birds, Birds!

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1992-01-01

    Ranger Rick's Nature Scope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. Contents are organized into the following sections: (1) "What Makes a Bird a Bird?," which provides…

  15. Fossil birds from the Late Cretaceous Los Alamitos Formation, Río Negro Province, Argentina

    NASA Astrophysics Data System (ADS)

    Agnolin, Federico L.; Martinelli, Agustín G.

    2009-02-01

    In this note we report new avian remains from the Late Cretaceous Los Alamitos Formation (Campanian-Maastrichtian) at the Los Alamitos locality, Río Negro Province, Argentina. Isolated remains referable to indeterminate Aves, ?Patagopterygiformes, indeterminate Ornithurae, cf. Hesperornithes and cf. Neornithes are described and discussed. The new genus and species Alamitornis minutus is erected to include a minute-sized and gracile bird, probably related to the non-volant ratite-like bird Patagopteryx. If correctly identified, the record of Hesperornithes may be the first for this group in the Southern Hemisphere. The Los Alamitos paleoavifauna represents one of the most diverse fossil bird assemblage from the Mesozoic of Gondwana known to date.

  16. Antarctic Entomology.

    PubMed

    Chown, Steven L; Convey, Peter

    2016-03-11

    The Antarctic region comprises the continent, the Maritime Antarctic, the sub-Antarctic islands, and the southern cold temperate islands. Continental Antarctica is devoid of insects, but elsewhere diversity varies from 2 to more than 200 species, of which flies and beetles constitute the majority. Much is known about the drivers of this diversity at local and regional scales; current climate and glacial history play important roles. Investigations of responses to low temperatures, dry conditions, and varying salinity have spanned the ecological to the genomic, revealing new insights into how insects respond to stressful conditions. Biological invasions are common across much of the region and are expected to increase as climates become warmer. The drivers of invasion are reasonably well understood, although less is known about the impacts of invasion. Antarctic entomology has advanced considerably over the past 50 years, but key areas, such as interspecific interactions, remain underexplored. PMID:26982437

  17. Antarctic meteorites

    NASA Astrophysics Data System (ADS)

    Cassidy, W. A.; Rancitelli, L. A.

    1982-04-01

    An abundance of meteorites has been discovered on two sites in the Antarctic which may assist in the study of the origins of meteorites and the history of the solar system. Characteristics particular to those meteorites discovered in this region are explained. These specimens, being well preserved due to the climate, have implications in the study of the cosmic ray flux through time, the meteoroid complex in space, and cosmic ray exposure ages. Implications for the study of the Antarctic, particularly the ice flow, are also discussed. Further discoveries of meteorites in this region are anticipated.

  18. The Bird.

    ERIC Educational Resources Information Center

    Hannon, Jean

    2001-01-01

    Students use a dead bird to learn about bird life, anatomy, and death. Students examine a bird body and discuss what happened to the bird. Uses outdoor education as a resource for learning about animals. (SAH)

  19. Bird Flu

    MedlinePlus

    ... viruses infect birds, including chickens, other poultry, and wild birds such as ducks. Most bird flu viruses ... become sick. It may also be possible to catch bird flu by eating poultry or eggs that ...

  20. Antarctic Genomics

    PubMed Central

    Clarke, Andrew; Cockell, Charles S.; Convey, Peter; Detrich III, H. William; Fraser, Keiron P. P.; Johnston, Ian A.; Methe, Barbara A.; Murray, Alison E.; Peck, Lloyd S.; Römisch, Karin; Rogers, Alex D.

    2004-01-01

    With the development of genomic science and its battery of technologies, polar biology stands on the threshold of a revolution, one that will enable the investigation of important questions of unprecedented scope and with extraordinary depth and precision. The exotic organisms of polar ecosystems are ideal candidates for genomic analysis. Through such analyses, it will be possible to learn not only the novel features that enable polar organisms to survive, and indeed thrive, in their extreme environments, but also fundamental biological principles that are common to most, if not all, organisms. This article aims to review recent developments in Antarctic genomics and to demonstrate the global context of such studies. PMID:18629155

  1. Antarctic micrometeorites

    NASA Technical Reports Server (NTRS)

    Kurat, G.; Koeberl, C.; Presper, T.; Brandstaetter, F.; Maurette, Michel

    1994-01-01

    Micrometeoroids in the size range 50-500 micron dominate the flux onto the Earth. Contrary to theoretical predictions, many of them survive atmospheric entry almost unchanged. Such micrometeorites can be collected from the Antarctic ice sheet where they account for a surprisingly large proportion of the total dust content of the ice. Early studies of this important class of extraterrestrial material have revealed that some Antarctic micrometeorites are similar to CM chondrites in chemical bulk composition and mineral composition, and a few seem to resemble CI chondrites. However, none of the micrometeorites investigated so far match CM or CI chondrites exactly, nor is there a match between average bulk micrometeorite composition and that of any other chondrite class. Also, the micrometeorite mineral chemistry is different from that of carbonaceous chondrites. Several elements are depleted in micrometeorites as compared to carbonaceous chondrites and some are enriched. The question arises whether these differences are pristine or if some of them are of secondary origin. On the basis of our data we will attempt to answer these questions, some of which have been addressed by us before.

  2. Dental Disparity and Ecological Stability in Bird-like Dinosaurs prior to the End-Cretaceous Mass Extinction.

    PubMed

    Larson, Derek W; Brown, Caleb M; Evans, David C

    2016-05-23

    The causes, rate, and selectivity of the end-Cretaceous mass extinction continue to be highly debated [1-5]. Extinction patterns in small, feathered maniraptoran dinosaurs (including birds) are important for understanding extant biodiversity and present an enigma considering the survival of crown group birds (Neornithes) and the extinction of their close kin across the end-Cretaceous boundary [6]. Because of the patchy Cretaceous fossil record of small maniraptorans [7-12], this important transition has not been closely examined in this group. Here, we test the hypothesis that morphological disparity in bird-like dinosaurs was decreasing leading up to the end-Cretaceous mass extinction, as has been hypothesized in some dinosaurs [13, 14]. To test this, we examined tooth morphology, an ecological indicator in fossil reptiles [15-19], from over 3,100 maniraptoran teeth from four groups (Troodontidae, Dromaeosauridae, Richardoestesia, and cf. Aves) across the last 18 million years of the Cretaceous. We demonstrate that tooth disparity, a proxy for variation in feeding ecology, shows no significant decline leading up to the extinction event within any of the groups. Tooth morphospace occupation also remains static over this time interval except for increased size during the early Maastrichtian. Our data provide strong support that extinction within this group occurred suddenly after a prolonged period of ecological stability. To explain this sudden extinction of toothed maniraptorans and the survival of Neornithes, we propose that diet may have been an extinction filter and suggest that granivory associated with an edentulous beak was a key ecological trait in the survival of some lineages. PMID:27112293

  3. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary.

    PubMed

    Longrich, Nicholas R; Tokaryk, Tim; Field, Daniel J

    2011-09-13

    The effect of the Cretaceous-Paleogene (K-Pg) (formerly Cretaceous-Tertiary, K-T) mass extinction on avian evolution is debated, primarily because of the poor fossil record of Late Cretaceous birds. In particular, it remains unclear whether archaic birds became extinct gradually over the course of the Cretaceous or whether they remained diverse up to the end of the Cretaceous and perished in the K-Pg mass extinction. Here, we describe a diverse avifauna from the latest Maastrichtian of western North America, which provides definitive evidence for the persistence of a range of archaic birds to within 300,000 y of the K-Pg boundary. A total of 17 species are identified, including 7 species of archaic bird, representing Enantiornithes, Ichthyornithes, Hesperornithes, and an Apsaravis-like bird. None of these groups are known to survive into the Paleogene, and their persistence into the latest Maastrichtian therefore provides strong evidence for a mass extinction of archaic birds coinciding with the Chicxulub asteroid impact. Most of the birds described here represent advanced ornithurines, showing that a major radiation of Ornithurae preceded the end of the Cretaceous, but none can be definitively referred to the Neornithes. This avifauna is the most diverse known from the Late Cretaceous, and although size disparity is lower than in modern birds, the assemblage includes both smaller forms and some of the largest volant birds known from the Mesozoic, emphasizing the degree to which avian diversification had proceeded by the end of the age of dinosaurs. PMID:21914849

  4. Mass extinction of birds at the Cretaceous–Paleogene (K–Pg) boundary

    PubMed Central

    Longrich, Nicholas R.; Tokaryk, Tim; Field, Daniel J.

    2011-01-01

    The effect of the Cretaceous-Paleogene (K-Pg) (formerly Cretaceous–Tertiary, K–T) mass extinction on avian evolution is debated, primarily because of the poor fossil record of Late Cretaceous birds. In particular, it remains unclear whether archaic birds became extinct gradually over the course of the Cretaceous or whether they remained diverse up to the end of the Cretaceous and perished in the K–Pg mass extinction. Here, we describe a diverse avifauna from the latest Maastrichtian of western North America, which provides definitive evidence for the persistence of a range of archaic birds to within 300,000 y of the K–Pg boundary. A total of 17 species are identified, including 7 species of archaic bird, representing Enantiornithes, Ichthyornithes, Hesperornithes, and an Apsaravis-like bird. None of these groups are known to survive into the Paleogene, and their persistence into the latest Maastrichtian therefore provides strong evidence for a mass extinction of archaic birds coinciding with the Chicxulub asteroid impact. Most of the birds described here represent advanced ornithurines, showing that a major radiation of Ornithurae preceded the end of the Cretaceous, but none can be definitively referred to the Neornithes. This avifauna is the most diverse known from the Late Cretaceous, and although size disparity is lower than in modern birds, the assemblage includes both smaller forms and some of the largest volant birds known from the Mesozoic, emphasizing the degree to which avian diversification had proceeded by the end of the age of dinosaurs. PMID:21914849

  5. Antarctic skuas recognize individual humans.

    PubMed

    Lee, Won Young; Han, Yeong-Deok; Lee, Sang-Im; Jablonski, Piotr G; Jung, Jin-Woo; Kim, Jeong-Hoon

    2016-07-01

    Recent findings report that wild animals can recognize individual humans. To explain how the animals distinguish humans, two hypotheses are proposed. The high cognitive abilities hypothesis implies that pre-existing high intelligence enabled animals to acquire such abilities. The pre-exposure to stimuli hypothesis suggests that frequent encounters with humans promote the acquisition of discriminatory abilities in these species. Here, we examine individual human recognition abilities in a wild Antarctic species, the brown skua (Stercorarius antarcticus), which lives away from typical human settlements and was only recently exposed to humans due to activities at Antarctic stations. We found that, as nest visits were repeated, the skua parents responded at further distances and were more likely to attack the nest intruder. Also, we demonstrated that seven out of seven breeding pairs of skuas selectively responded to a human nest intruder with aggression and ignored a neutral human who had not previously approached the nest. The results indicate that Antarctic skuas, a species that typically inhabited in human-free areas, are able to recognize individual humans who disturbed their nests. Our findings generally support the high cognitive abilities hypothesis, but this ability can be acquired during a relatively short period in the life of an individual as a result of interactions between individual birds and humans. PMID:26939544

  6. Heavy metals in Antarctic organisms

    SciTech Connect

    Moreno, J.E.A. de; Moreno, V.J.; Gerpe, M.S.; Vodopivez, C.

    1997-02-01

    To evaluate levels of essential (zinc and copper) and non-essential (mercury and cadmium) heavy metals, 34 species of organisms from different areas close to the Antarctic Peninsula were analysed. These included algae, filter-feeders, omnivorous invertebrates and vertebrates. Mercury was not detected, while cadmium was found in the majority of organisms analysed (detection limit was 0.05 ppm for both metals). The highest cadmium concentration was observed in the starfish Odontaster validus. Anthozoans, sipunculids and nudibranchs showed maximum levels of zinc, while the highest copper level was found in the gastropod Trophon brevispira. Mercury and cadmium levels in fishes were below the detection limit. Concentrations of essential and non-essential metals in birds were highest in liver followed by muscle and eggs. Cadmium and mercury levels in muscle of southern elephant seals were above the detection limit, whereas in Antarctic fur seals they were below it. The objective of the study was to gather baseline information for metals in Antarctic Ocean biota that may be needed to detect, measure and monitor future environmental changes. 46 refs., 7 figs., 8 tabs.

  7. 78 FR 27260 - Comment Request: Antarctic Conservation Act Application Permit Form

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-09

    ... type of object to be taken (plant, native mammal, or native bird. Use of the Information The purpose of... Act of 1978, Public Law 95-541, as amended by the Antarctic Science, Tourism, and Conservation Act...

  8. Occurrence of yeasts in faecal samples from Antarctic and South American seabirds.

    PubMed

    Chryssanthou, E; Wennberg, H; Bonnedahl, J; Olsen, B

    2011-11-01

    During an expedition to the Southern Argentinean town of Ushuaia, the Antarctic Peninsula, Antarctic Islands and the Falkland Islands, we collected 94 faecal specimens from wild birds to screen for yeast within the different bird species. The yeast species were identified by morphological features and commercial characterisation kits. From 54% of the specimens, we isolated 122 strains representing 29 yeast species. Debaryomyces hansenii, Candida lambica and Candida krusei were the most frequently isolated species. We found a plethora of yeasts in birds living in proximity to humans, whereas birds living in more remote areas were colonised with a lower number of fungal species. PMID:21672044

  9. 45 CFR 670.20 - Designation of native birds.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 3 2012-10-01 2012-10-01 false Designation of native birds. 670.20 Section 670.20 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Native Mammals, Birds, Plants, and Invertebrates §...

  10. 45 CFR 670.20 - Designation of native birds.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Designation of native birds. 670.20 Section 670.20 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Native Mammals, Birds, Plants, and Invertebrates §...

  11. 45 CFR 670.20 - Designation of native birds.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 3 2011-10-01 2011-10-01 false Designation of native birds. 670.20 Section 670.20 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Native Mammals, Birds, Plants, and Invertebrates §...

  12. 45 CFR 670.20 - Designation of native birds.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 3 2013-10-01 2013-10-01 false Designation of native birds. 670.20 Section 670.20 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Native Mammals, Birds, Plants, and Invertebrates §...

  13. 45 CFR 670.20 - Designation of native birds.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 3 2014-10-01 2014-10-01 false Designation of native birds. 670.20 Section 670.20 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Native Mammals, Birds, Plants, and Invertebrates §...

  14. In search of human-associated bacterial pathogens in Antarctic wildlife: report from six penguin colonies regularly visited by tourists.

    PubMed

    Bonnedahl, Jonas; Broman, Tina; Waldenström, Jonas; Palmgren, Helena; Niskanen, Taina; Olsen, Björn

    2005-08-01

    We investigated the potential role of Antarctic tourism in the introduction of human-associated pathogens into Antarctic wildlife. We collected and analyzed 233 fecal samples from eight bird species. The samples were collected at six localities on the Antarctic Peninsula, which often is visited by tourists. Every sample was investigated for pathogens of potential human origin: Campylobacter jejuni, Salmonella spp., and Yersina spp. None of these bacteria was found. Our data suggest that the tourism industry so far has achieved its goal of not introducing pathogens into the Antarctic region. There is, however, an urgent need to further investigate the situation in areas closer to permanent Antarctic settlements. PMID:16201212

  15. 77 FR 23766 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-20

    ... amended by the Antarctic Science, Tourism and Conservation Act of 1996, has developed regulations for the... Protected Areas (ASPA's), The applicant plans to enter ASPA 116-New College Valley, Cape Bird; ASPA 121-Cape... imagery will used for further scientific analysis. Location ASPA 116-New College Valley, Cape Bird;...

  16. At-Sea Distribution and Prey Selection of Antarctic Petrels and Commercial Krill Fisheries

    PubMed Central

    Descamps, Sébastien; Tarroux, Arnaud; Cherel, Yves; Delord, Karine; Godø, Olaf Rune; Kato, Akiko; Krafft, Bjørn A.; Lorentsen, Svein-Håkon; Ropert-Coudert, Yan; Skaret, Georg; Varpe, Øystein

    2016-01-01

    Commercial fisheries may impact marine ecosystems and affect populations of predators like seabirds. In the Southern Ocean, there is an extensive fishery for Antarctic krill Euphausia superba that is projected to increase further. Comparing distribution and prey selection of fishing operations versus predators is needed to predict fishery-related impacts on krill-dependent predators. In this context, it is important to consider not only predators breeding near the fishing grounds but also the ones breeding far away and that disperse during the non-breeding season where they may interact with fisheries. In this study, we first quantified the overlap between the distribution of the Antarctic krill fisheries and the distribution of a krill dependent seabird, the Antarctic petrel Thalassoica antarctica, during both the breeding and non-breeding season. We tracked birds from the world biggest Antarctic petrel colony (Svarthamaren, Dronning Maud Land), located >1000 km from the main fishing areas, during three consecutive seasons. The overall spatial overlap between krill fisheries and Antarctic petrels was limited but varied greatly among and within years, and was high in some periods during the non-breeding season. In a second step, we described the length frequency distribution of Antarctic krill consumed by Antarctic petrels, and compared this with results from fisheries, as well as from diet studies in other krill predators. Krill taken by Antarctic petrels did not differ in size from that taken by trawls or from krill taken by most Antarctic krill predators. Selectivity for specific Antarctic krill stages seems generally low in Antarctic predators. Overall, our results show that competition between Antarctic petrels and krill fisheries is currently likely negligible. However, if krill fisheries are to increase in the future, competition with the Antarctic petrel may occur, even with birds breeding thousands of kilometers away. PMID:27533327

  17. At-Sea Distribution and Prey Selection of Antarctic Petrels and Commercial Krill Fisheries.

    PubMed

    Descamps, Sébastien; Tarroux, Arnaud; Cherel, Yves; Delord, Karine; Godø, Olaf Rune; Kato, Akiko; Krafft, Bjørn A; Lorentsen, Svein-Håkon; Ropert-Coudert, Yan; Skaret, Georg; Varpe, Øystein

    2016-01-01

    Commercial fisheries may impact marine ecosystems and affect populations of predators like seabirds. In the Southern Ocean, there is an extensive fishery for Antarctic krill Euphausia superba that is projected to increase further. Comparing distribution and prey selection of fishing operations versus predators is needed to predict fishery-related impacts on krill-dependent predators. In this context, it is important to consider not only predators breeding near the fishing grounds but also the ones breeding far away and that disperse during the non-breeding season where they may interact with fisheries. In this study, we first quantified the overlap between the distribution of the Antarctic krill fisheries and the distribution of a krill dependent seabird, the Antarctic petrel Thalassoica antarctica, during both the breeding and non-breeding season. We tracked birds from the world biggest Antarctic petrel colony (Svarthamaren, Dronning Maud Land), located >1000 km from the main fishing areas, during three consecutive seasons. The overall spatial overlap between krill fisheries and Antarctic petrels was limited but varied greatly among and within years, and was high in some periods during the non-breeding season. In a second step, we described the length frequency distribution of Antarctic krill consumed by Antarctic petrels, and compared this with results from fisheries, as well as from diet studies in other krill predators. Krill taken by Antarctic petrels did not differ in size from that taken by trawls or from krill taken by most Antarctic krill predators. Selectivity for specific Antarctic krill stages seems generally low in Antarctic predators. Overall, our results show that competition between Antarctic petrels and krill fisheries is currently likely negligible. However, if krill fisheries are to increase in the future, competition with the Antarctic petrel may occur, even with birds breeding thousands of kilometers away. PMID:27533327

  18. Exploring the Relationship between Skeletal Mass and Total Body Mass in Birds

    PubMed Central

    Martin-Silverstone, Elizabeth; Vincze, Orsolya; McCann, Ria; Jonsson, Carl H. W.; Palmer, Colin; Kaiser, Gary; Dyke, Gareth

    2015-01-01

    Total body mass (TBM) is known to be related to a number of different osteological features in vertebrates, including limb element measurements and total skeletal mass. The relationship between skeletal mass and TBM in birds has been suggested as a way of estimating the latter in cases where only the skeleton is known (e.g., fossils). This relationship has thus also been applied to other extinct vertebrates, including the non-avian pterosaurs, while other studies have used additional skeletal correlates found in modern birds to estimate TBM. However, most previous studies have used TBM compiled from the literature rather than from direct measurements, producing values from population averages rather than from individuals. Here, we report a new dataset of 487 extant birds encompassing 79 species that have skeletal mass and TBM recorded at the time of collection or preparation. We combine both historical and new data for analyses with phylogenetic control and find a similar and well-correlated relationship between skeletal mass and TBM. Thus, we confirm that TBM and skeletal mass are accurate proxies for estimating one another. We also look at other factors that may have an effect on avian body mass, including sex, ontogenetic stage, and flight mode. While data are well-correlated in all cases, phylogeny is a major control on TBM in birds strongly suggesting that this relationship is not appropriate for estimating the total mass of taxa outside of crown birds, Neornithes (e.g., non-avian dinosaurs, pterosaurs). Data also reveal large variability in both bird skeletal and TBM within single species; caution should thus be applied when using published mass to test direct correlations with skeletal mass and bone lengths. PMID:26509531

  19. Bird guard

    DOEpatents

    Fairchild, Dana M.

    2010-03-02

    The bird guard provides a device to protect electrical insulators comprising a central shaft; a clamp attached to an end of the shaft to secure the device to a transmission tower; a top and bottom cover to shield transmission tower insulators; and bearings to allow the guard to rotate in order to frighten birds away from the insulators.

  20. The Antarctic Ice.

    ERIC Educational Resources Information Center

    Radok, Uwe

    1985-01-01

    The International Antarctic Glaciological Project has collected information on the East Antarctic ice sheet since 1969. Analysis of ice cores revealed climatic history, and radar soundings helped map bedrock of the continent. Computer models of the ice sheet and its changes over time will aid in predicting the future. (DH)

  1. The Antarctic Ozone Hole.

    ERIC Educational Resources Information Center

    Stolarski, Richard S.

    1988-01-01

    Discusses the Airborne Antarctic Ozone Experiment (1987) and the findings of the British Antarctic Survey (1985). Proposes two theories for the appearance of the hole in the ozone layer over Antarctica which appears each spring; air pollution and natural atmospheric shifts. Illustrates the mechanics of both. Supports worldwide chlorofluorocarbon…

  2. Antarctic Meteorology and Climatology

    NASA Astrophysics Data System (ADS)

    King, J. C.; Turner, J.

    1997-07-01

    This book is a comprehensive survey of the climatology and meteorology of Antarctica. The first section of the book reviews the methods by which we can observe the Antarctic atmosphere and presents a synthesis of climatological measurements. In the second section, the authors consider the processes that maintain the observed climate, from large-scale atmospheric circulation to small-scale processes. The final section reviews our current knowledge of the variability of Antarctic climate and the possible effects of "greenhouse" warming. The authors stress links among the Antarctic atmosphere, other elements of the Antarctic climate system (oceans, sea ice and ice sheets), and the global climate system. This volume will be of greatest interest to meteorologists and climatologists with a specialized interest in Antarctica, but it will also appeal to researchers in Antarctic glaciology, oceanography and biology. Graduates and undergraduates studying physical geography, and the earth, atmospheric and environmental sciences will find much useful background material in the book.

  3. Birds, Examining Your Environment.

    ERIC Educational Resources Information Center

    MacBean, John C.; And Others

    Designed to provide new and different ways of observing birds rather than simply identifying them, this book attempts to develop skills for how to look at birds. Activities in each of the four sections, "Live Birds,""Birds' Eggs,""Birds' Nests," and "Dead Birds," are specifically planned to get one involved with birds in their natural environment.…

  4. 77 FR 26048 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-02

    .... 95-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996, has developed..., Caughley Beach, Cape Bird; ASPA 117--Avian Island; ASPA 121--Cape Royds; ASPA 124--Cape Crozier; ASPA 125... Island; ASPA 116--New College Valley, Caughley Beach, Cape Bird; ASPA 117--Avian Island; ASPA 121--...

  5. 76 FR 61117 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-03

    .... 95-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996, has developed... Heights, Ross Island (ASPA 122), Backdoor Bay, Cape Royds (ASPA 157), and New College Valley, Cape Bird... Bird (ASPA 116). Dates November 11, 2011 to December 31, 2011. Nadene G. Kennedy, Permit...

  6. 76 FR 58049 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    .... 95-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996, has developed... Island (ASPA 105), New College Valley, Cape Bird (ASPA 116), Cape Royds (ASPA 121), Arrival Heights (ASPA... College Valley, Cape Bird, ASPA 121-Cape Royds, ASPA 122-Arrival Heights, ASPA 124-Cape Crozier, ASPA...

  7. The Antarctic Submillimetre Telescope

    NASA Astrophysics Data System (ADS)

    Minier, V.; Olmi, L.; Durand, G.; Daddi, E.; Israel, F.; Kramer, C.; Lagage, P.-O.; de Petris, M.; Sabbatini, L.; Spinoglio, L.; Schneider, N.; Tothill, N.; Tremblin, P.; Valenziano, L.; Veyssière, C.

    This report aims to provide a summary of the status of our Antarctic Submillimetre Telescope (AST) project up to date. It is a very new project for Antarctic astronomy. Necessary prerequisites for a future deployment of a large size telescope infrastructure have been tested in years 2007 and 2008. The knowledge of the transmission, frost formation and temperature gradient were fundamental parameters before starting a feasibility study. The telescope specifications and requirements are currently discussed with the industrial partnership.

  8. Linking the evolution of body shape and locomotor biomechanics in bird-line archosaurs.

    PubMed

    Allen, Vivian; Bates, Karl T; Li, Zhiheng; Hutchinson, John R

    2013-05-01

    Locomotion in living birds (Neornithes) has two remarkable features: feather-assisted flight, and the use of unusually crouched hindlimbs for bipedal support and movement. When and how these defining functional traits evolved remains controversial. However, the advent of computer modelling approaches and the discoveries of exceptionally preserved key specimens now make it possible to use quantitative data on whole-body morphology to address the biomechanics underlying this issue. Here we use digital body reconstructions to quantify evolutionary trends in locomotor biomechanics (whole-body proportions and centre-of-mass position) across the clade Archosauria. We use three-dimensional digital reconstruction to estimate body shape from skeletal dimensions for 17 archosaurs along the ancestral bird line, including the exceptionally preserved, feathered taxa Microraptor, Archaeopteryx, Pengornis and Yixianornis, which represent key stages in the evolution of the avian body plan. Rather than a discrete transition from more-upright postures in the basal-most birds (Avialae) and their immediate outgroup deinonychosauria, our results support hypotheses of a gradual, stepwise acquisition of more-crouched limb postures across much of theropod evolution, although we find evidence of an accelerated change within the clade Maniraptora (birds and their closest relatives, such as deinonychosaurs). In addition, whereas reduction of the tail is widely accepted to be the primary morphological factor correlated with centre-of-mass position and, hence, evolution of hindlimb posture, we instead find that enlargement of the pectoral limb and several associated trends have a much stronger influence. Intriguingly, our support for the onset of accelerated morpho-functional trends within Maniraptora is closely correlated with the evolution of flight. Because we find that the evolution of enlarged forelimbs is strongly linked, via whole-body centre of mass, to hindlimb function during

  9. Marine pelagic ecosystems: the west Antarctic Peninsula.

    PubMed

    Ducklow, Hugh W; Baker, Karen; Martinson, Douglas G; Quetin, Langdon B; Ross, Robin M; Smith, Raymond C; Stammerjohn, Sharon E; Vernet, Maria; Fraser, William

    2007-01-29

    The marine ecosystem of the West Antarctic Peninsula (WAP) extends from the Bellingshausen Sea to the northern tip of the peninsula and from the mostly glaciated coast across the continental shelf to the shelf break in the west. The glacially sculpted coastline along the peninsula is highly convoluted and characterized by deep embayments that are often interconnected by channels that facilitate transport of heat and nutrients into the shelf domain. The ecosystem is divided into three subregions, the continental slope, shelf and coastal regions, each with unique ocean dynamics, water mass and biological distributions. The WAP shelf lies within the Antarctic Sea Ice Zone (SIZ) and like other SIZs, the WAP system is very productive, supporting large stocks of marine mammals, birds and the Antarctic krill, Euphausia superba. Ecosystem dynamics is dominated by the seasonal and interannual variation in sea ice extent and retreat. The Antarctic Peninsula is one among the most rapidly warming regions on Earth, having experienced a 2 degrees C increase in the annual mean temperature and a 6 degrees C rise in the mean winter temperature since 1950. Delivery of heat from the Antarctic Circumpolar Current has increased significantly in the past decade, sufficient to drive to a 0.6 degrees C warming of the upper 300 m of shelf water. In the past 50 years and continuing in the twenty-first century, the warm, moist maritime climate of the northern WAP has been migrating south, displacing the once dominant cold, dry continental Antarctic climate and causing multi-level responses in the marine ecosystem. Ecosystem responses to the regional warming include increased heat transport, decreased sea ice extent and duration, local declines in icedependent Adélie penguins, increase in ice-tolerant gentoo and chinstrap penguins, alterations in phytoplankton and zooplankton community composition and changes in krill recruitment, abundance and availability to predators. The climate

  10. Marine pelagic ecosystems: the West Antarctic Peninsula

    PubMed Central

    Ducklow, Hugh W; Baker, Karen; Martinson, Douglas G; Quetin, Langdon B; Ross, Robin M; Smith, Raymond C; Stammerjohn, Sharon E; Vernet, Maria; Fraser, William

    2006-01-01

    The marine ecosystem of the West Antarctic Peninsula (WAP) extends from the Bellingshausen Sea to the northern tip of the peninsula and from the mostly glaciated coast across the continental shelf to the shelf break in the west. The glacially sculpted coastline along the peninsula is highly convoluted and characterized by deep embayments that are often interconnected by channels that facilitate transport of heat and nutrients into the shelf domain. The ecosystem is divided into three subregions, the continental slope, shelf and coastal regions, each with unique ocean dynamics, water mass and biological distributions. The WAP shelf lies within the Antarctic Sea Ice Zone (SIZ) and like other SIZs, the WAP system is very productive, supporting large stocks of marine mammals, birds and the Antarctic krill, Euphausia superba. Ecosystem dynamics is dominated by the seasonal and interannual variation in sea ice extent and retreat. The Antarctic Peninsula is one among the most rapidly warming regions on Earth, having experienced a 2°C increase in the annual mean temperature and a 6°C rise in the mean winter temperature since 1950. Delivery of heat from the Antarctic Circumpolar Current has increased significantly in the past decade, sufficient to drive to a 0.6°C warming of the upper 300 m of shelf water. In the past 50 years and continuing in the twenty-first century, the warm, moist maritime climate of the northern WAP has been migrating south, displacing the once dominant cold, dry continental Antarctic climate and causing multi-level responses in the marine ecosystem. Ecosystem responses to the regional warming include increased heat transport, decreased sea ice extent and duration, local declines in ice-dependent Adélie penguins, increase in ice-tolerant gentoo and chinstrap penguins, alterations in phytoplankton and zooplankton community composition and changes in krill recruitment, abundance and availability to predators. The climate/ecological gradients

  11. Sugars in Antarctic aerosol

    NASA Astrophysics Data System (ADS)

    Barbaro, Elena; Kirchgeorg, Torben; Zangrando, Roberta; Vecchiato, Marco; Piazza, Rossano; Barbante, Carlo; Gambaro, Andrea

    2015-10-01

    The processes and transformations occurring in the Antarctic aerosol during atmospheric transport were described using selected sugars as source tracers. Monosaccharides (arabinose, fructose, galactose, glucose, mannose, ribose, xylose), disaccharides (sucrose, lactose, maltose, lactulose), alcohol-sugars (erythritol, mannitol, ribitol, sorbitol, xylitol, maltitol, galactitol) and anhydrosugars (levoglucosan, mannosan and galactosan) were measured in the Antarctic aerosol collected during four different sampling campaigns. For quantification, a sensitive high-pressure anion exchange chromatography was coupled with a single quadrupole mass spectrometer. The method was validated, showing good accuracy and low method quantification limits. This study describes the first determination of sugars in the Antarctic aerosol. The total mean concentration of sugars in the aerosol collected at the "Mario Zucchelli" coastal station was 140 pg m-3; as for the aerosol collected over the Antarctic plateau during two consecutive sampling campaigns, the concentration amounted to 440 and 438 pg m-3. The study of particle-size distribution allowed us to identify the natural emission from spores or from sea-spray as the main sources of sugars in the coastal area. The enrichment of sugars in the fine fraction of the aerosol collected on the Antarctic plateau is due to the degradation of particles during long-range atmospheric transport. The composition of sugars in the coarse fraction was also investigated in the aerosol collected during the oceanographic cruise.

  12. Rebound of Antarctic ozone

    NASA Astrophysics Data System (ADS)

    Salby, Murry; Titova, Evgenia; Deschamps, Lilia

    2011-05-01

    Restrictions on CFCs have led to a gradual decline of Equivalent Effective Stratospheric Chlorine (EESC). A rebound of Antarctic ozone, however, has remained elusive, masked by large interannual changes that dominate its current evolution. A positive response of ozone is not expected to emerge for at least 1-2 decades, possibly not for half a century. We show that interannual changes of the Antarctic ozone hole are accounted for almost perfectly by changes in dynamical forcing of the stratosphere. The close relationship enables dynamically-induced changes of ozone to be removed, unmasking the climate signal associated with CFCs. The component independent of dynamically-induced changes exhibits a clear upward trend over the last decade - the first signature of a rebound in Antarctic ozone. It enables ozone to be tracked relative to CFCs and other changes of climate.

  13. Antarctic terrestrial ecosystems

    SciTech Connect

    Walton, D.W.H.

    1987-01-01

    The Maritime and Continental Antarctic terrestrial ecosystems are considered in the context of environmental impacts - habitat destruction, alien introductions, and pollution. Four types of pollution are considered: nutrients, radionuclides, inert materials, and noxious chemicals. Their ability to recover from perturbation is discussed in the light of present scientific knowledge, and the methods used to control impacts are reviewed. It is concluded that techniques of waste disposal are still inadequate, adequate training in environmental and conservation principles for Antarctic personnel in many countries is lacking, and scientific investigations may be a much more serious threat than tourism to the integrity of these ecosystems. Some priorities crucial to future management are suggested.

  14. The Completeness of the Fossil Record of Mesozoic Birds: Implications for Early Avian Evolution

    PubMed Central

    Brocklehurst, Neil; Upchurch, Paul; Mannion, Philip D.; O'Connor, Jingmai

    2012-01-01

    Many palaeobiological analyses have concluded that modern birds (Neornithes) radiated no earlier than the Maastrichtian, whereas molecular clock studies have argued for a much earlier origination. Here, we assess the quality of the fossil record of Mesozoic avian species, using a recently proposed character completeness metric which calculates the percentage of phylogenetic characters that can be scored for each taxon. Estimates of fossil record quality are plotted against geological time and compared to estimates of species level diversity, sea level, and depositional environment. Geographical controls on the avian fossil record are investigated by comparing the completeness scores of species in different continental regions and latitudinal bins. Avian fossil record quality varies greatly with peaks during the Tithonian-early Berriasian, Aptian, and Coniacian–Santonian, and troughs during the Albian-Turonian and the Maastrichtian. The completeness metric correlates more strongly with a ‘sampling corrected’ residual diversity curve of avian species than with the raw taxic diversity curve, suggesting that the abundance and diversity of birds might influence the probability of high quality specimens being preserved. There is no correlation between avian completeness and sea level, the number of fluviolacustrine localities or a recently constructed character completeness metric of sauropodomorph dinosaurs. Comparisons between the completeness of Mesozoic birds and sauropodomorphs suggest that small delicate vertebrate skeletons are more easily destroyed by taphonomic processes, but more easily preserved whole. Lagerstätten deposits might therefore have a stronger impact on reconstructions of diversity of smaller organisms relative to more robust forms. The relatively poor quality of the avian fossil record in the Late Cretaceous combined with very patchy regional sampling means that it is possible neornithine lineages were present throughout this interval but

  15. Diagnosing Antarctic Fog

    NASA Astrophysics Data System (ADS)

    Lazzara, M. A.

    2010-07-01

    Fog affects aviation and other logistical operations in the Antarctic; nevertheless limited studies have been conducted to understand fog behavior in this part of the world. A study has been conducted in the Ross Island region of Antarctica, the location of McMurdo Station and Scott Base - the main stations of the United States and New Zealand Antarctic programs, respectively. Using tools such as multi-channel satellites observations and supported by in situ radiosonde and ground-based automatic weather station observations, combined with back trajectory and mesoscale numerical models, discover that austral summer fog events are "advective" in temperament. The diagnosis finds a primary source region from the southeast over the Ross Ice Shelf (over 72% of the cases studied) while a minority of cases point toward a secondary fog source region to the north along the Scott Coast of the Ross Sea with influences from the East Antarctic Plateau. Part of this examination confirms existing anecdotes from forecasters and weather observers, while refuting others about fog and its behavior in this environment. This effort marks the beginning of our understanding of Antarctic fog behavior.

  16. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Certificate for pet birds, commercial birds, zoological birds, and research birds. 93.104 Section 93.104 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND...

  17. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Certificate for pet birds, commercial birds, zoological birds, and research birds. 93.104 Section 93.104 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND...

  18. Birds Kept as Pets

    MedlinePlus

    ... restricts the importation of pet birds from certain countries and enforces a 30-day quarantine for all imported birds except those that come from Canada. People interested in importing pet birds should visit the USDA non-US Origin Pet Bird Importation website . Choosing a bird Match ...

  19. The Brazilian research contribution to knowledge of the plant communities from Antarctic ice free areas.

    PubMed

    Pereira, Antonio B; Putzke, Jair

    2013-09-01

    This work aims to summarize the results of research carried out by Brazilian researchers on the plant communities of Antarctic ice free areas during the last twenty five years. Since 1988 field work has been carried out in Elephant Island, King George Island, Nelson Island and Deception Island. During this period six papers were published on the chemistry of lichens, seven papers on plant taxonomy, five papers on plant biology, two studies on UVB photoprotection, three studies about the relationships between plant communities and bird colonies and eleven papers on plant communities from ice free areas. At the present, Brazilian botanists are researching the plant communities of Antarctic ice free areas in order to understand their relationships to soil microbial communities, the biodiversity, the distribution of the plants populations and their relationship with birds colonies. In addition to these activities, a group of Brazilian researchers are undertaking studies related to Antarctic plant genetic diversity, plant chemistry and their biotechnological applications. PMID:24068084

  20. Diving birds

    NASA Astrophysics Data System (ADS)

    Clanet, Christophe; Masson, Lucien; McKinley, Gareth; Cohen, Robert; Ecole polytechnique Collaboration; MIT Collaboration

    2015-11-01

    Many seabirds (gannets, pelicans, gulls, albatrosses) dive into water at high speeds (25 m/s) in order to capture underwater preys. Diving depths of 20 body lengths are reported in the literature. This value is much larger than the one achieved by men, which is of the order of 5. We study this difference by comparing the impact of slender vs bluff bodies. We show that, contrary to bluff bodies, the penetration depth of slender bodies presents a maximum value for a specific impact velocity that we connect to the velocity of diving birds.

  1. Plant and bird presence strongly influences the microbial communities in soils of Admiralty Bay, Maritime Antarctica.

    PubMed

    Teixeira, Lia C R S; Yeargeau, Etienne; Balieiro, Fabiano C; Piccolo, Marisa C; Peixoto, Raquel S; Greer, Charles W; Rosado, Alexandre S

    2013-01-01

    Understanding the environmental factors that shape microbial communities is crucial, especially in extreme environments, like Antarctica. Two main forces were reported to influence Antarctic soil microbes: birds and plants. Both birds and plants are currently undergoing relatively large changes in their distribution and abundance due to global warming. However, we need to clearly understand the relationship between plants, birds and soil microorganisms. We therefore collected rhizosphere and bulk soils from six different sampling sites subjected to different levels of bird influence and colonized by Colobanthus quitensis and Deschampsia antarctica in Admiralty Bay, King George Island, Maritime Antarctic. Microarray and qPCR assays targeting 16S rRNA genes of specific taxa were used to assess microbial community structure, composition and abundance and analyzed with a range of soil physico-chemical parameters. The results indicated significant rhizosphere effects in four out of the six sites, including areas with different levels of bird influence. Acidobacteria were significantly more abundant in soils with little bird influence (low nitrogen) and in bulk soil. In contrast, Actinobacteria were significantly more abundant in the rhizosphere of both plant species. At two of the sampling sites under strong bird influence (penguin colonies), Firmicutes were significantly more abundant in D. antarctica rhizosphere but not in C. quitensis rhizosphere. The Firmicutes were also positively and significantly correlated to the nitrogen concentrations in the soil. We conclude that the microbial communities in Antarctic soils are driven both by bird and plants, and that the effect is taxa-specific. PMID:23840411

  2. Differences between Antarctic and non-Antarctic meteorites: An assessment

    SciTech Connect

    Koeberl, C. ); Cassidy, W.A. )

    1991-01-01

    The discovery of a statistically significant number of meteorites in Antarctica over the past 20 years has posed many questions. One of the most intriguing suggestions that came up during the study of the Antarctic samples was that there might be a difference between the parent populations of Antarctic and non-Antarctic samples was that there might be a difference between the parent populations of Antarctic and non-Antarctic meteorites. This interpretation was put forward after the detection of a significant difference in the abundances of volatile and mobile trace elements in H, L, and C chondrites and achondrites. Other major differences include the occurrence of previously rare or unknown meteorites, different meteorite-type frequencies, petrographic characteristics, oxygen isotopic compositions, and smaller average masses. Not all differences between the Antarctic and non-Antarctic meteorite populations can be explained by weathering, pairing, or different collection procedures. Variable trace element abundances and distinct differences in the thermal history and thermoluminescence characteristics have to be interpreted as being pre-terrestrial in origin. Such differences imply the existence of meteoroid streams, whose existence poses problems in the framework of our current knowledge of celestial mechanics. In this paper we summarize the contributions in this series and provide a review of the current state of the question for the reality and cause of differences between Antarctic and non-Antarctic meteorites.

  3. Viruses in Antarctic lakes

    NASA Technical Reports Server (NTRS)

    Kepner, R. L. Jr; Wharton, R. A. Jr; Suttle, C. A.; Wharton RA, J. r. (Principal Investigator)

    1998-01-01

    Water samples collected from four perennially ice-covered Antarctic lakes during the austral summer of 1996-1997 contained high densities of extracellular viruses. Many of these viruses were found to be morphologically similar to double-stranded DNA viruses that are known to infect algae and protozoa. These constitute the first observations of viruses in perennially ice-covered polar lakes. The abundance of planktonic viruses and data suggesting substantial production potential (relative to bacteria] secondary and photosynthetic primary production) indicate that viral lysis may be a major factor in the regulation of microbial populations in these extreme environments. Furthermore, we suggest that Antarctic lakes may be a reservoir of previously undescribed viruses that possess novel biological and biochemical characteristics.

  4. Antarctic Meteorite Newsletter

    NASA Technical Reports Server (NTRS)

    Lindstrom, Marilyn

    2000-01-01

    This newsletter contains something for everyone! It lists classifications of about 440 meteorites mostly from the 1997 and 1998 ANSMET (Antarctic Search for Meteorites) seasons. It also gives descriptions of about 45 meteorites of special petrologic type. These include 1 iron, 17 chondrites (7 CC, 1 EC, 9 OC) and 27 achondrites (25 HED, UR). Most notable are an acapoloite (GRA98028) and an olivine diogenite (GRA98108).

  5. Antarctic Photochemistry: Uncertainty Analysis

    NASA Technical Reports Server (NTRS)

    Stewart, Richard W.; McConnell, Joseph R.

    1999-01-01

    Understanding the photochemistry of the Antarctic region is important for several reasons. Analysis of ice cores provides historical information on several species such as hydrogen peroxide and sulfur-bearing compounds. The former can potentially provide information on the history of oxidants in the troposphere and the latter may shed light on DMS-climate relationships. Extracting such information requires that we be able to model the photochemistry of the Antarctic troposphere and relate atmospheric concentrations to deposition rates and sequestration in the polar ice. This paper deals with one aspect of the uncertainty inherent in photochemical models of the high latitude troposphere: that arising from imprecision in the kinetic data used in the calculations. Such uncertainties in Antarctic models tend to be larger than those in models of mid to low latitude clean air. One reason is the lower temperatures which result in increased imprecision in kinetic data, assumed to be best characterized at 298K. Another is the inclusion of a DMS oxidation scheme in the present model. Many of the rates in this scheme are less precisely known than are rates in the standard chemistry used in many stratospheric and tropospheric models.

  6. Thermoluminescence and Antarctic meteorites

    NASA Technical Reports Server (NTRS)

    Sears, D. W. G.; Hasan, F. A.

    1986-01-01

    The level of natural thermoluminescence (TL) in meteorites is the result of competition between build-up, due to exposure to cosmic radiation, and thermal decay. Antarctic meteorites tend to have lower natural TL than non-Antarctic meteorites because of their generally larger terrestrial ages. However, since a few observed falls have low TL due to a recent heating event, such as passage within approximately 0.7 astronomical units of the Sun, this could also be the case for some Antarctic meteorites. Dose rate variations due to shielding, heating during atmospheric passage, and anomalous fading also cause natural TL variations, but the effects are either relatively small, occur infrequently, or can be experimentally circumvented. The TL sensitivity of meteorites reflects the abundance and nature of the feldspar. Thus intense shock, which destroys feldspar, causes the TL sensitivity to decrease by 1 to 2 orders of magnitude, while metamorphism, which generates feldspar through the devitrification of glass, causes TL sensitivity to increase by a factor of approximately 10000. The TL-metamorphism relationship is particularly strong for the lowest levels of metamorphism. The order-disorder transformation in feldspar also affect the TL emission characteristics and thus TL provides a means of paleothermometry.

  7. Antarctic sea ice change and variability - Physical and ecological implications

    NASA Astrophysics Data System (ADS)

    Massom, Robert A.; Stammerjohn, Sharon E.

    2010-08-01

    Although Antarctic sea ice is undergoing a slight increase in overall extent, major regional changes are occurring in its spatio-temporal characteristics (most notably in sea ice seasonality). Biologically significant aspects of Antarctic sea ice are evaluated, emphasising the importance of scale and thermodynamics versus dynamics. Changing sea ice coverage is having major direct and indirect though regionally-dependent effects on ecosystem structure and function, with the most dramatic known effects to date occurring in the West Antarctic Peninsula region. There is mounting evidence that loss of sea ice has affected multiple levels of the marine food web in a complex fashion and has triggered cascading effects. Impacts on primary production, Antarctic krill, fish, marine mammals and birds are assessed, and are both negative and positive. The review includes recent analysis of change/variability in polynyas and fast ice, and also highlights the significance of extreme events (which have paradoxical impacts). Possible future scenarios are investigated in the light of the predicted decline in sea ice by 2100 e.g. increased storminess/waviness, numbers of icebergs and snowfall. Our current lack of knowledge on many aspects of sea ice-related change and biological response is emphasised.

  8. International Workshop on Antarctic Meteorites

    NASA Technical Reports Server (NTRS)

    Annexstad, J. O.; Schultz, L.; Waenke, H.

    1986-01-01

    Topics addressed include: meteorite concentration mechanisms; meteorites and the Antarctic ice sheet; iron meteorites; iodine overabundance in meteorites; entrainment, transport, and concentration of meteorites in polar ice sheets; weathering of stony meteorites; cosmic ray records; radiocarbon dating; element distribution and noble gas isotopic abundances in lunar meteorites; thermoanalytical characterization; trace elements; thermoluminescence; parent sources; and meteorite ablation and fusion spherules in Antarctic ice.

  9. Torn Paper Birds.

    ERIC Educational Resources Information Center

    Harrington, Carolyn Lang

    1998-01-01

    Describes a lesson for third-grade students that begins with an examination of bird prints done by John James Audubon and moves into the students creating their own torn paper birds. Introduces the students to the beauty of birds and focuses on the environmental issues that face birds and their habitats. (CMK)

  10. Biodiversity and biogeography of Antarctic and sub-Antarctic mollusca

    NASA Astrophysics Data System (ADS)

    Linse, Katrin; Griffiths, Huw J.; Barnes, David K. A.; Clarke, Andrew

    2006-04-01

    For many decades molluscan data have been critical to the establishment of the concept of a global-scale increase in species richness from the poles to the equator. Low polar diversity is key to this latitudinal cline in diversity. Here we investigate richness patterns in the two largest classes of molluscs at both local and regional scales throughout the Southern Ocean. We show that biodiversity is very patchy in the Southern Ocean (at the 1000-km scale) and test the validity of historical biogeographic sub-regions and provinces. We used multivariate analysis of biodiversity patterns at species, genus and family levels to define richness hotspots within the Southern Ocean and transition areas. This process identified the following distinct sub-regions in the Southern Ocean: Antarctic Peninsula, Weddell Sea, East Antarctic—Dronning Maud Land, East Antarctic—Enderby Land, East Antarctic—Wilkes Land, Ross Sea, and the independent Scotia arc and sub Antarctic islands. Patterns of endemism were very different between the bivalves and gastropods. On the basis of distributional ranges and radiation centres of evolutionarily successful families and genera we define three biogeographic provinces in the Southern Ocean: (1) the continental high Antarctic province excluding the Antarctic Peninsula, (2) the Scotia Sea province including the Antarctic Peninsula, and (3) the sub Antarctic province comprising the islands in the vicinity of the Antarctic Circumpolar Current.

  11. Gazetteer of the Antarctic

    USGS Publications Warehouse

    U.S. Board on Geographic Names; Defense Mapping Agency; U.S. Geological Survey; National Science Foundation

    1989-01-01

    This gazetteer lists antarctic names approved by the United States Board on Geographic Names and by the Secretary of the Interior. The Board is the interagency body created by law to standardize and promulgate geographic names for official purposes. As the official standard for names in Antarctica, the gazetteer assures accuracy and uniformity for the specialist and the general user alike. Unlike the last (1981) edition, now out of print, the book contains neither historical notes nor textual descriptions of features. The gazetteer contains names of features in Antarctica and the area extending northward to the Antarctic Convergence that have been approved by the Board as recently as mid-1989. It supersedes previous Board gazetteers for the area. For each geographic feature, the book contains the name, cross references if any, and latitude and longitude. Coverage corresponds to that of maps at the scale of 1:250,000 or larger for islands, coastal Antarctica, and mountains and ranges of the continent. Much of the interior of Antarctica, an ice plateau, has been mapped at a smaller scale and is nearly devoid of features and toponyms. All of the names are for natural features; scientific stations are not listed. For the names of submarine features, reference should be made to the Gazetteer of Undersea Features, U.S. Board on Geographic Names (1981).

  12. Revisiting Antarctic Ozone Depletion

    NASA Astrophysics Data System (ADS)

    Grooß, Jens-Uwe; Tritscher, Ines; Müller, Rolf

    2015-04-01

    Antarctic ozone depletion is known for almost three decades and it has been well settled that it is caused by chlorine catalysed ozone depletion inside the polar vortex. However, there are still some details, which need to be clarified. In particular, there is a current debate on the relative importance of liquid aerosol and crystalline NAT and ice particles for chlorine activation. Particles have a threefold impact on polar chlorine chemistry, temporary removal of HNO3 from the gas-phase (uptake), permanent removal of HNO3 from the atmosphere (denitrification), and chlorine activation through heterogeneous reactions. We have performed simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) employing a recently developed algorithm for saturation-dependent NAT nucleation for the Antarctic winters 2011 and 2012. The simulation results are compared with different satellite observations. With the help of these simulations, we investigate the role of the different processes responsible for chlorine activation and ozone depletion. Especially the sensitivity with respect to the particle type has been investigated. If temperatures are artificially forced to only allow cold binary liquid aerosol, the simulation still shows significant chlorine activation and ozone depletion. The results of the 3-D Chemical Transport Model CLaMS simulations differ from purely Lagrangian longtime trajectory box model simulations which indicates the importance of mixing processes.

  13. RADARSAT: The Antarctic Mapping Project

    NASA Technical Reports Server (NTRS)

    Jezek, Kenneth C.; Lindstrom, E. (Technical Monitor)

    2002-01-01

    The first Antarctic Imaging Campaign (AIC) occurred during the period September 9, 1997 through October 20, 1997. The AIC utilized the unique attributes of the Canadian RADARSAT-1 to acquire the first, high-resolution, synthetic aperture imagery covering the entire Antarctic Continent. Although the primary goal of the mission was the acquisition of image data, the nearly flawless execution of the mission enabled additional collections of exact repeat orbit data. These data, covering an extensive portion of the interior Antarctic, potentially are suitable for interferometric analysis of topography and surface velocity. This document summarizes the Project through completion with delivery of products to the NASA DAACs.

  14. Psychological factors in the antarctic.

    PubMed

    Rothblum, E D

    1990-05-01

    For the people who live and work in the Antarctic, isolation and extreme physical conditions cause considerable stress. This article reviews psychological research on Antarctic residents, focusing on factors related to the isolation (effective personnel selection, positive adjustment, conflict, and reintegration into the home environment) and factors related to the physical environment (the extreme cold, high altitude, increased radiation, sensory deprivation, and seasonal changes in activity level). Finally, Antarctic research has been applied to the study of future space travel and space station habitation. PMID:2189993

  15. 78 FR 56744 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-13

    ... salvage shed bird feathers and broken pieces of eggshell from Adelie, chinstrap and Gentoo penguins and... Antarctic tern. The salvaged feathers and eggshell pieces would be incorporated into pieces of artwork that would be publicly displayed. Feathers and eggshells would be collected in the Cape Shirreff ASPA as...

  16. 75 FR 22433 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-28

    ...-541), as amended by the Antarctic Science, Tourism and Conservation Act of 1996, has developed... (ASPA 121), Cape Bird, and Beaufort Island (ASPA 105) to study penguins and the effect of age... antennas will be set up at Cape Royds. Location: Cape Crozier (ASPA 124), Cape Royds (ASPA 121), Cape...

  17. Antarctic stratospheric ice crystals

    SciTech Connect

    Goodman, J. ); Toon, O.B.; Pueschel, R.F.; Snetsinger, K.G. ) Verma, S. )

    1989-11-30

    Ice crystals were replicated over the Palmer Peninsula at approximately 72{degree}S on six occasions during the 1987 Airborne Antarctic Ozone Experiment. The sampling altitude was between 12.5 and 18.5 km (45-65 thousand ft pressure altitude) with the temperature between 190 and 201 K. The atmosphere was subsaturated with respect to ice in all cases. The collected crystals were predominantly solid and hollow columns. The largest crystals were sampled at lower altitudes where the potential temperature was below 400 K. While the crystals were larger than anticipated, their low concentration results in a total surface area that is less than one tenth of the total aerosol surface area. The large ice crystals may play an important role in the observed stratospheric dehydration processes through sedimentation. Evidence of scavenging of submicron particles further suggests that the ice crystals may be effective in the removal of stratospheric chemicals.

  18. Antarctic Meteorite Location Map Series

    NASA Technical Reports Server (NTRS)

    Schutt, John (Editor); Fessler, Brian (Editor); Cassidy, William (Editor)

    1989-01-01

    Antarctica has been a prolific source of meteorites since meteorite concentrations were discovered in 1969. The Antarctic Search For Meteorites (ANSMET) project has been active over much of the Trans-Antarctic Mountain Range. The first ANSMET expedition (a joint U.S.-Japanese effort) discovered what turned out to be a significant concentration of meteorites at the Allan Hills in Victoria Land. Later reconnaissance in this region resulted in the discovery of meteorite concentrations on icefields to the west of the Allan Hills, at Reckling Moraine, and Elephant Moraine. Antarctic meteorite location maps (reduced versions) of the Allan Hills main, near western, middle western, and far western icefields and the Elephant Moraine icefield are presented. Other Antarctic meteorite location maps for the specimens found by the ANSMET project are being prepared.

  19. Antarctic Crabs: Invasion or Endurance?

    PubMed Central

    Griffiths, Huw J.; Whittle, Rowan J.; Roberts, Stephen J.; Belchier, Mark; Linse, Katrin

    2013-01-01

    Recent scientific interest following the “discovery” of lithodid crabs around Antarctica has centred on a hypothesis that these crabs might be poised to invade the Antarctic shelf if the recent warming trend continues, potentially decimating its native fauna. This “invasion hypothesis” suggests that decapod crabs were driven out of Antarctica 40–15 million years ago and are only now returning as “warm” enough habitats become available. The hypothesis is based on a geographically and spatially poor fossil record of a different group of crabs (Brachyura), and examination of relatively few Recent lithodid samples from the Antarctic slope. In this paper, we examine the existing lithodid fossil record and present the distribution and biogeographic patterns derived from over 16,000 records of Recent Southern Hemisphere crabs and lobsters. Globally, the lithodid fossil record consists of only two known specimens, neither of which comes from the Antarctic. Recent records show that 22 species of crabs and lobsters have been reported from the Southern Ocean, with 12 species found south of 60°S. All are restricted to waters warmer than 0°C, with their Antarctic distribution limited to the areas of seafloor dominated by Circumpolar Deep Water (CDW). Currently, CDW extends further and shallower onto the West Antarctic shelf than the known distribution ranges of most lithodid species examined. Geological evidence suggests that West Antarctic shelf could have been available for colonisation during the last 9,000 years. Distribution patterns, species richness, and levels of endemism all suggest that, rather than becoming extinct and recently re-invading from outside Antarctica, the lithodid crabs have likely persisted, and even radiated, on or near to Antarctic slope. We conclude there is no evidence for a modern-day “crab invasion”. We recommend a repeated targeted lithodid sampling program along the West Antarctic shelf to fully test the validity of the

  20. What Makes a Bird a Bird?

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Presents background information and activities that focus on how birds are classified, how they are different from other animals, and the main characteristics of the class "Aves." Activities include an objective, recommended age level(s), subject area(s), list of materials needed, and procedures. Two ready-to-copy pages with bird illustrations are…

  1. 45 CFR 670.25 - Designation of specially protected species of native mammals, birds, and plants.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Designation of specially protected species of native mammals, birds, and plants. 670.25 Section 670.25 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS...

  2. 45 CFR 670.25 - Designation of specially protected species of native mammals, birds, and plants.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 3 2011-10-01 2011-10-01 false Designation of specially protected species of native mammals, birds, and plants. 670.25 Section 670.25 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS...

  3. Avian Influenza in Birds

    MedlinePlus

    ... and even kill certain domesticated bird species including chickens, ducks, and turkeys. Infected birds can shed avian ... virus’ ability to cause disease and mortality in chickens in a laboratory setting [2.5 MB, 64 ...

  4. Birds: Old Questions and New.

    ERIC Educational Resources Information Center

    Flannery, Maura C.

    2002-01-01

    Discusses questions such as how birds fly and the meaning of bird songs. Explains the relationship between birds and ecological activism and points out the excitement in research and observation of birds. (Contains 34 references.) (YDS)

  5. Audubon Bird Study Program.

    ERIC Educational Resources Information Center

    National Audubon Society, New York, NY.

    Included are a student reader, "The Story of Birds," a leaders' guide, a large colored Audubon bird chart, and a separate guide for the chart. The student reader is divided into eleven sections which relate to the various physical and behavioral features of birds such as feathers, feeding habits as related to the shape of bills and feet, nests,…

  6. The Antarctic Master Directory -- a resource for Antarctic Scientists

    NASA Astrophysics Data System (ADS)

    Scharfen, G.; Bauer, R.

    2002-12-01

    Under the auspices of the Antarctic Treaty, a group of nations conducting Antarctic scientific research have created the Antarctic Master Directory (AMD), a resource for Antarctic scientists. The AMD is a Web-based, searchable directory containing data descriptions (metadata in the form of DIF entries) of Antarctic scientific data, and is a node of the International Directory Network/Global Change Master Directory (IDN/GCMD). The data descriptions in the AMD, essentially a data catalog of Antarctic scientific data, include information about what data were collected, where they were collected, when they were collected, who the scientists are, who the point of contact is, and information about the format of the data and what documentation and bibliographic information exists. As part of the AMD effort, the National Science Foundation Office of Polar Programs (OPP) funds the National Snow and Ice Data Center to operate the U.S. Antarctic Data Coordination Center (USADCC), the US focal point for the AMD. The USADCC assists PIs as they meet the requirements of the OPP "Guidelines and Award Conditions for Scientific Data", which identify the conditions for awards and responsibilities of PIs regarding the archival of data, and submission of metadata, resulting from their NSF OPP grants. The USADCC offers access to free, easy-to-use online tools that PIs can use to create the data descriptions that the NSF policy data requires. We provide advice to PIs on how to meet the data policy requirements, and can answer specific questions on related issues. Scientists can access data set descriptions submitted to the AMD, by thousands of scientists around the world, from the USADCC web pages.

  7. Antarctic Miocene Climate

    NASA Astrophysics Data System (ADS)

    Ashworth, A. C.; Lewis, A. R.

    2013-12-01

    Fossils from Antarctic Miocene terrestrial deposits, coupled with stratigraphic, geochemical and paleontological data from marine boreholes, provide new insights into the climatic history of the continent. During the Miocene, ice caps coalesced to form ice sheets and vegetated surfaces gave way to barren expanses. The cryospheric changes especially have global climatic implications. The fossil data consists of diatoms, pollen and spores, and macroscopic remains of plants, ostracods, insects, molluscs and a fish. Plant fossils include wood and leaves of Nothofagus (southern beech), seeds of several vascular plants, including Ranunculus (buttercup), Hippuris (mare's-tail) and Myriophyllum (watermilfoil), megaspores of Isoetes (quillwort), and moss species. The insect chitin consists of larval head capsules of Chironomidae (midges) and exoskeletal parts of Coleoptera (beetles). The molluscs include freshwater gastropods and bivalves. The majority of these taxa are likely descendants of taxa that had survived on the continent from the Paleogene or earlier. Even though early Miocene glaciations may have been large, the climate was never cold enough to cause the extinction of the biota, which probably survived in coastal refugia. Early Miocene (c. 20 Ma) macrofossils from the McMurdo Dry Valleys (77°S) support palynological interpretations from the Cape Roberts and ANDRILL marine records that the upland vegetation was a shrub tundra. Mean summer temperature (MST) in the uplands was c. 6°C and possibly higher at the coast. The climate was wet, supporting mires and lakes. By the mid-Miocene, even though the climate continued to be wet. MST was c. 4°C which was too cold to support Nothofagus and most vascular plant species. Stratigraphic evidence indicates that the time between the Early and Mid-Miocene was a time of repeated ice advances and retreats of small glaciers originating from ice caps. At c. 14 Ma there appears to have been a modal shift in climate to

  8. Environmental contamination in Antarctic ecosystems.

    PubMed

    Bargagli, R

    2008-08-01

    Although the remote continent of Antarctica is perceived as the symbol of the last great wilderness, the human presence in the Southern Ocean and the continent began in the early 1900s for hunting, fishing and exploration, and many invasive plant and animal species have been deliberately introduced in several sub-Antarctic islands. Over the last 50 years, the development of research and tourism have locally affected terrestrial and marine coastal ecosystems through fuel combustion (for transportation and energy production), accidental oil spills, waste incineration and sewage. Although natural "barriers" such as oceanic and atmospheric circulation protect Antarctica from lower latitude water and air masses, available data on concentrations of metals, pesticides and other persistent pollutants in air, snow, mosses, lichens and marine organisms show that most persistent contaminants in the Antarctic environment are transported from other continents in the Southern Hemisphere. At present, levels of most contaminants in Antarctic organisms are lower than those in related species from other remote regions, except for the natural accumulation of Cd and Hg in several marine organisms and especially in albatrosses and petrels. The concentrations of organic pollutants in the eggs of an opportunistic top predator such as the south polar skua are close to those that may cause adverse health effects. Population growth and industrial development in several countries of the Southern Hemisphere are changing the global pattern of persistent anthropogenic contaminants and new classes of chemicals have already been detected in the Antarctic environment. Although the Protocol on Environmental Protection to the Antarctic Treaty provides strict guidelines for the protection of the Antarctic environment and establishes obligations for all human activity in the continent and the Southern Ocean, global warming, population growth and industrial development in countries of the Southern

  9. Community structure across a large-scale ocean productivity gradient: Marine bird assemblages of the Southern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Hyrenbach, K. David; Veit, Richard R.; Weimerskirch, Henri; Metzl, Nicolas; Hunt, George L., Jr.

    2007-07-01

    Our objective was to understand how marine birds respond to oceanographic variability across the Southern Indian Ocean using data collected during an 16-day cruise (4-21 January 2003). We quantified concurrent water mass distributions, ocean productivity patterns, and seabird distributions across a heterogeneous pelagic ecosystem from subtropical to sub-Antarctic waters. We surveyed 5155 km and sighted 15,606 birds from 51 species, and used these data to investigate how seabirds respond to spatial variability in the structure and productivity of the ocean. We addressed two spatial scales: the structure of seabird communities across macro-mega scale (1000 s km) biogeographic domains, and their coarse-scale (10 s km) aggregation at hydrographic and bathymetric gradients. Both seabird density and species composition changed with latitudinal and onshore-offshore gradients in depth, water temperature, and chlorophyll-a concentration. The average seabird density increased across the subtropical convergence (STC) from 2.4 birds km -2 in subtropical waters to 23.8 birds km -2 in sub-Antarctic waters. The composition of the avifauna also differed across biogeographic domains. Prions ( Pachyptila spp.) accounted for 57% of all sub-Antarctic birds, wedge-tailed shearwaters ( Puffinus pacificus) accounted for 46% of all subtropical birds, and Indian Ocean yellow-nosed albatross ( Thallasarche carteri) accounted for 32% of all birds in the STC. While surface feeders were the most abundant foraging guild across the study area, divers were disproportionately more numerous in the sub-Antarctic domain, and plungers were disproportionately more abundant in subtropical waters. Seabird densities were also higher within shallow shelf-slope regions, especially in sub-Antarctic waters, where large numbers of breeding seabirds concentrated. However, we did not find elevated seabird densities along the STC, suggesting that this broad frontal region is not a site of enhanced aggregation.

  10. Melting glaciers: a probable source of DDT to the Antarctic marine ecosystem.

    PubMed

    Geisz, Heidi N; Dickhut, Rebecca M; Cochran, Michele A; Fraser, William R; Ducklow, Hugh W

    2008-06-01

    Persistent organic pollutants reach polar regions by long-range atmospheric transport and biomagnify through the food web accumulating in higher trophic level predators. We analyzed Adélie penguin (Pygoscelis adeliae) samples collected from 2004 to 2006 to evaluate current levels of sigmaDDT (p,p'-DDT + p,p'-DDE) in these birds, which are confined to Antarctica. Ratios of p,p'-DDT to p,p'-DDE in Adélie penguins have declined significantly since 1964 indicating current exposure to old rather than new sources of sigmaDDT. However, sigmaDDT has not declined in Adélie penguins from the Western Antarctic Peninsula for more than 30 years and the presence of p,p'-DDT in these birds indicates that there is a current source of DDT to the Antarctic marine food web. DDT has been banned or severely restricted since peak use in the 1970s, implicating glacier meltwater as a likely source for DDT contamination in coastal Antarctic seas. Our estimates indicate that 1-4 kg x y(-1) sigmaDDT are currently being released into coastal waters along the Western Antarctic Ice Sheet due to glacier ablation. PMID:18589951

  11. Antarctic Meteorite Classification and Petrographic Database Enhancements

    NASA Astrophysics Data System (ADS)

    Todd, N. S.; Satterwhite, C. E.; Righter, K.

    2012-03-01

    Describes the Antarctic Meteorite Classification Database and the latest enhancements made to the data acquisition process used to provide updated meteorite data concurrent with the publication of the Antarctic Meteorite Newsletter twice a year.

  12. Life hung by a thread: endurance of Antarctic fauna in glacial periods.

    PubMed

    Thatje, Sven; Hillenbrand, Claus-Dieter; Mackensen, Andreas; Larter, Rob

    2008-03-01

    Today, Antarctica exhibits some of the harshest environmental conditions for life on Earth. During the last glacial period, Antarctic terrestrial and marine life was challenged by even more extreme environmental conditions. During the present interglacial period, polar life in the Southern Ocean is sustained mainly by large-scale primary production. We argue that during the last glacial period, faunal populations in the Antarctic were limited to very few areas of local marine productivity (polynyas), because complete, multiannual sea-ice and ice shelf coverage shut down most of the Southern Ocean productivity within today's seasonal sea-ice zone. Both marine sediments containing significant numbers of planktonic and benthic foraminifera and fossil bird stomach oil deposits in the adjacent Antarctic hinterland provide indirect evidence for the existence of polynyas during the last glacial period. We advocate that the existence of productive oases in the form of polynyas during glacial periods was essential for the survival of marine and most higher-trophic terrestrial fauna. Reduced to such refuges, much of today's life in the high Antarctic realm might have hung by a thread during the last glacial period, because limited resources available to the food web restricted the abundance and productivity of both Antarctic terrestrial and marine life. PMID:18459332

  13. Antarctic Peninsula and Weddell Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Numerous icebergs are breaking out of the sea ice in the Southern Ocean surrounding the Antarctic Peninsula. This true-color MODIS image from November 13, 2001, shows several icebergs drifting out of the Weddell Sea. The Antarctic Peninsula (left) reaches out into the Drake Passage, which separates the southern tip of South America from Antarctica. Warmer temperatures have cleared a tiny patch of bare ground at the Peninsula's tip. The predominant ocean current in the area is the Antarctic Circumpolar Current ('circum' meaning 'around'), which is also the 'West Wind Drift.' The current is the largest permanent current in the world, and water is moved eastward by westerly winds. Icebergs leaving the Weddell Sea are likely to be moved north and east by the current. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  14. Multidecadal warming of Antarctic waters.

    PubMed

    Schmidtko, Sunke; Heywood, Karen J; Thompson, Andrew F; Aoki, Shigeru

    2014-12-01

    Decadal trends in the properties of seawater adjacent to Antarctica are poorly known, and the mechanisms responsible for such changes are uncertain. Antarctic ice sheet mass loss is largely driven by ice shelf basal melt, which is influenced by ocean-ice interactions and has been correlated with Antarctic Continental Shelf Bottom Water (ASBW) temperature. We document the spatial distribution of long-term large-scale trends in temperature, salinity, and core depth over the Antarctic continental shelf and slope. Warming at the seabed in the Bellingshausen and Amundsen seas is linked to increased heat content and to a shoaling of the mid-depth temperature maximum over the continental slope, allowing warmer, saltier water greater access to the shelf in recent years. Regions of ASBW warming are those exhibiting increased ice shelf melt. PMID:25477461

  15. Integrated Science and Logistical Planning to Support Big Questions in Antarctic Science

    NASA Astrophysics Data System (ADS)

    Vaughan, D. G.; Stockings, T. M.

    2015-12-01

    Each year, British Antarctic Survey (BAS) supports an extensive programme of science at five Antarctic and sub-Antarctic stations, ranging from the tiny Bird Island Research Station at 54°S in the South Atlantic, to the massive, and fully re-locatable, Halley Research Station on Brunt Ice Shelf at 75°S. The BAS logistics hub, Rothera Research Station on the Antarctic Peninsula supports deployment of deep-field and airborne field campaigns through much of the Antarctic continent, and an innovative new UK polar research vessel is under design, and planned to enter service in the Southern Ocean in 2019. BAS's core science programme covering all aspects of physical, biological and geological science is delivered by our own science teams, but every year many other UK scientists and overseas collaborators also access BAS's Antarctic logistics to support their own programmes. As an integrated science and logistics provider, BAS is continuously reviewing its capabilities and operational procedures to ensure that the future long-term requirements of science are optimally supported. Current trends are towards providing the capacity for heavier remote operations and larger-scale field camps, increasing use of autonomous ocean and airborne platforms, and increasing opportunities to provide turnkey solutions for low-cost experimental deployments. This talk will review of expected trends in Antarctic science and the opportunities to conduct science in Antarctica. It will outline the anticipated logistic developments required to support future stakeholder-led and strategically-directed science programmes, and the long-term ambitions of our science communities indentified in several recent horizon-scanning activities.

  16. Antarctic analogs for Enceladus

    NASA Astrophysics Data System (ADS)

    Murray, A. E.; Andersen, D. T.; McKay, C. P.

    2014-12-01

    Enceladus is a new world for Astrobiology. The Cassini discovery of the icy plume emanating from the South Polar region indicates an active world, where detection of water, organics, sodium, and nano-particle silica in the plume strongly suggests that the source is a subsurface salty ocean reservoir. Recent gravity data from Cassini confirms the presence of a regional sea extending north to 50°S. An ocean habitat under a thick ice cover is perhaps a recurring theme in the Outer Solar System, but what makes Enceladus unique is that the plume jetting out into space is carrying samples of this ocean. Therefore, through the study of Enceladus' plumes we can gain new insights not only of a possible habitable world in the Solar Systems, but also about the formation and evolution of other icy-satellites. Cassini has been able to fly through this plume - effectively sampling the ocean. It is time to plan for future missions that do more detailed analyses, possibly return samples back to Earth and search for evidence of life. To help prepare for such missions, the need for earth-based analog environments is essential for logistical, methodological (life detection) and theoretical development. We have undertaken studies of two terrestrial environments that are close analogs to Enceladus' ocean: Lake Vida and Lake Untersee - two ice-sealed Antarctic lakes that represent physical, chemical and possibly biological analogs for Enceladus. By studying the diverse biology and physical and chemical constraints to life in these two unique lakes we will begin to understand the potential habitability of Enceladus and other icy moons, including possible sources of nutrients and energy, which together with liquid water are the key ingredients for life. Analog research such as this will also enable us to develop and test new strategies to search for evidence of life on Enceladus.

  17. Antarctic Ozone Hole, 2000

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Each spring the ozone layer over Antarctica nearly disappears, forming a 'hole' over the entire continent. The hole is created by the interaction of some man-made chemicals-freon, for example-with Antarctica's unique weather patterns and extremely cold temperatures. Ozone in the stratosphere absorbs ultraviolet radiation from the sun, thereby protecting living things. Since the ozone hole was discovered many of the chemicals that destroy ozone have been banned, but they will remain in the atmosphere for decades. In 2000, the ozone hole grew quicker than usual and exceptionally large. By the first week in September the hole was the largest ever-11.4 million square miles. The top image shows the average total column ozone values over Antarctica for September 2000. (Total column ozone is the amount of ozone from the ground to the top of the atmosphere. A relatively typical measurement of 300 Dobson Units is equivalent to a layer of ozone 0.12 inches thick on the Earth's surface. Levels below 220 Dobson Units are considered to be significant ozone depletion.) The record-breaking hole is likely the result of lower than average ozone levels during the Antarctic fall and winter, and exceptionally cold temperatures. In October, however (bottom image), the hole shrank dramatically, much more quickly than usual. By the end of October, the hole was only one-third of it's previous size. In a typical year, the ozone hole does not collapse until the end of November. NASA scientists were surprised by this early shrinking and speculate it is related to the region's weather. Global ozone levels are measured by the Total Ozone Mapping Spectrometer (TOMS). For more information about ozone, read the Earth Observatory's ozone fact sheet, view global ozone data and see these ozone images. Images by Greg Shirah, NASA GSFC Scientific Visualization Studio.

  18. Diseases Transmitted by Birds.

    PubMed

    Levison, Matthew E

    2015-08-01

    Although many people these days actually work very hard at leisure time activities, diseases are most commonly acquired from birds during the course of work in the usual sense of the term, not leisure. However, travel for pleasure to areas where the diseases are highly endemic puts people at risk of acquiring some of these bird-related diseases (for example, histoplasmosis and arbovirus infections), as does ownership of birds as pets (psittacosis). PMID:26350315

  19. Feeding repellence in Antarctic bryozoans.

    PubMed

    Figuerola, Blanca; Núñez-Pons, Laura; Moles, Juan; Avila, Conxita

    2013-11-01

    The Antarctic sea star Odontaster validus and the amphipod Cheirimedon femoratus are important predators in benthic communities. Some bryozoans are part of the diet of the asteroid and represent both potential host biosubstrata and prey for this omnivorous lysianassid amphipod. In response to such ecological pressure, bryozoans are expected to develop strategies to deter potential predators, ranging from physical to chemical mechanisms. However, the chemical ecology of Antarctic bryozoans has been scarcely studied. In this study we evaluated the presence of defenses against predation in selected species of Antarctic bryozoans. The sympatric omnivorous consumers O. validus and C. femoratus were selected to perform feeding assays with 16 ether extracts (EE) and 16 butanol extracts (BE) obtained from 16 samples that belonged to 13 different bryozoan species. Most species (9) were active (12 EE and 1 BE) in sea star bioassays. Only 1 BE displayed repellence, indicating that repellents against the sea star are mainly lipophilic. Repellence toward C. femoratus was found in all species in different extracts (10 EE and 12 BE), suggesting that defenses against the amphipod might be both lipophilic and hydrophilic. Interspecific and intraspecific variability of bioactivity was occasionally detected, suggesting possible environmental inductive responses, symbiotic associations, and/or genetic variability. Multivariate analysis revealed similarities among species in relation to bioactivities of EE and/or BE. These findings support the hypothesis that, while in some cases alternative chemical or physical mechanisms may also provide protection, repellent compounds play an important role in Antarctic bryozoans as defenses against predators. PMID:24221581

  20. Cosmogenic records in Antarctic meteorites

    NASA Technical Reports Server (NTRS)

    Goswami, J. N.; Nishiizumi, K.

    1983-01-01

    Aliquot samples of 29 Antarctic L and H chondrites are analyzed for their nuclear track records and Mn-53 activities. The track density in the analyzed samples ranges from 10 to the 4th to approximately 6 x 10 to the 6th per sq cm. A significant finding is the observation of track-rich grains in a set of four L3 chondrites (ALHA 77215, 77216, 77217, and 77252), suspected of belonging to the same fall based on petrographic observations. An additional sample, ALHA 78105, an L6 chondrite, also has track-rich grains. Mn-53 activity is at near saturation level in approximately 65 percent of the analyzed samples, suggesting exposure ages of greater than 10 m.y. in these cases. Very few H chondrites from the 7-m.y. exposure age peak are apparently sampled among the ones investigated in this study. Approximately 6 percent and 4 percent, respectively, of the Antarctic H and L chondrites analyzed thus far for their cosmogenic records have precompaction irradiation features. A combined analysis of Mn-53 and nuclear track data makes it possible to confirm or rule out the proposed pairing of several sets of Antarctic meteorites and to estimate the preatmospheric sizes of some of these meteorites. The results suggest that most of the small Antarctic meteorites (less than 1 kg) have suffered high (greater than 95 percent) ablation mass-loss.

  1. Birds on power lines

    NASA Astrophysics Data System (ADS)

    Arnaldo Redinz, José

    2014-07-01

    Why can a bird safely rest on a high-voltage power line? We discuss three effects that can lead to the development of voltages and currents in the bird's body. To explain the absence of electric shocks, we give numerical estimates of these voltages and currents obtained from the standard solution for the voltage along a two-wire transmission line.

  2. Migratory Birds. Issue Pac.

    ERIC Educational Resources Information Center

    Fish and Wildlife Service (Dept. of Interior), Washington, DC.

    The materials in this educational packet are designed for use with students in grades 4 through 7. They consist of an overview, teaching guides and student data sheets for three activities, and a poster. The overview discusses why, how, where, and when birds migrate as well as problems birds encounter while migrating; the importance of research…

  3. Spermiogenesis in birds

    PubMed Central

    Aire, Tom A

    2014-01-01

    Current knowledge on avian spermiogenesis, including strengths and weaknesses, has been reviewed. Information on avian spermiogenesis considerably lags behind that in mammals because of the paucity of reports in birds. Spermiogenesis in passerine birds has received even much less attention than in non-passerine birds. Mechanisms underlying morphogenesis of the acrosome and nucleus, and roles of microtubular assemblies are poorly understood. The proximal centriole found in non-passerine birds, but hitherto considered to be absent in passerine birds, has recently been described in spermatids and mature spermatozoa of 2 passeridan species, including the Masked weaver for which new and detailed spermiogenetic information is provided in this review. A great deal more studies on spermiogenesis, and spermatogenesis generally, in various avian species are required to considerably enhance knowledge of this phenomenon, contribute to comparative spermatology, provide a basis for appropriate applied studies, and contribute to understanding of phylogeny in this vast order of vertebrates. PMID:26413401

  4. Radarsat Antarctic Mapping Project: Antarctic Imaging Campaign 2

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Radarsat Antarctic Mapping Project is a collaboration between NASA and the Canadian Space Agency to map Antarctica using synthetic aperture radar (SAR). The first Antarctic Mapping Mission (AMM-1) was successfully completed in October 1997. Data from the acquisition phase of the 1997 campaign have been used to achieve the primary goal of producing the first, high-resolution SAR image map of Antarctica. The limited amount of data suitable for interferometric analysis have also been used to produce remarkably detailed maps of surface velocity for a few selected regions. Most importantly, the results from AMM-1 are now available to the general science community in the form of various resolution, radiometrically calibrated and geometrically accurate image mosaics. The second Antarctic imaging campaign occurred during the fall of 2000. Modified from AMM-1, the satellite remained in north looking mode during AMM-2 restricting coverage to regions north of about -80 degrees latitude. But AMM-2 utilized for the first time RADARSAT-1 fine beams providing an unprecedented opportunity to image many of Antarctica's fast glaciers whose extent was revealed through AMM-1 data. AMM-2 also captured extensive data suitable for interferometric analysis of the surface velocity field. This report summarizes the science goals, mission objectives, and project status through the acquisition phase and the start of the processing phase. The reports describes the efforts of team members including Alaska SAR Facility, Jet Propulsion Laboratory, Vexcel Corporation, Goddard Space Flight Center, Wallops Flight Facility, Ohio State University, Environmental Research Institute of Michigan, White Sands Facility, Canadian Space Agency Mission Planning and Operations Groups, and the Antarctic Mapping Planning Group.

  5. Christmas Island birds returning

    NASA Astrophysics Data System (ADS)

    Six months after their mass exodus, birds are beginning to return to Christmas Island. Roughly 17 million birds, almost the entire adult bird population, either perished or fled their mid-Pacific atoll home last autumn, leaving behind thousands of nestlings to starve (Eos, April 5, 1983, p. 131). It is believed that the strong El Niño altered the ecology of the surrounding waters and forced the birds to flee. Christmas Island is the world's largest coral atoll.“Ocean and atmosphere scientists are unsure of future directions for the El Niño conditions and cannot now predict what will happen to the birds in the coming months,” said Ralph W. Schreiber, curator of ornithology at the Natural History Museum of Los Angeles County in California. Heisthe ornithologist who discovered the disappearance. “The recovery of the bird populations depends on the food supply in the waters surrounding the island.” The island's birds feed exclusively on small fish and squid.

  6. Chemical studies of differentiated meteorites. I - Labile trace elements in Antarctic and non-Antarctic eucrites

    NASA Technical Reports Server (NTRS)

    Paul, Rick L.; Lipschutz, Michael E.

    1990-01-01

    Element contents of Ag, Au, Bi, Cd, Co, Cs, Ga, In, Rb, Sb, Se, Te, Tl, U, and Zn were analyzed, using RNAA, in 25 Antarctic and nine non-Antarctic eucrites to determine whether these two populations differ significantly in thermal history and derive from the same or different eucrite parent body. Data for these 15 elements indicate that basaltic Antarctic and non-Antarctic eucrite populations reflect the same genetic processes and, hence, come from the same parent asteroid.

  7. Oxyspiruriasis in zoo birds.

    PubMed

    Vellayan, S; Jeffery, J; Oothuman, P; Zahedi, M; Krishnasamy, M; Paramaswaran, S; Rohela, M; Abdul-Aziz, N M

    2012-06-01

    Oxyspiruriasis caused by the bird eyeworm, Oxyspirura mansoni, a thelaziid nematode, in three species of pheasants, 3 Chrysolophus pictus (golden pheasant), 7 Lophura nycthemera (silver pheasant) and 9 Phasianus colchicus (common pheasant) in Zoo Negara Malaysia are reported. Birds with the disease were treated with a solution of 0.5% iodine or 0.5% lysol. Antistress powder for 4 days in water and non-strep vitamin powder in water was also provided. Control measures included removal of the cockroach intermediate host, Pycnoscelus surinamensis (Surinam cockroach) from the vicinity of the birds. The golden pheasant is a new host for O. mansoni in peninsular Malaysia. PMID:22735854

  8. Geographic names of the Antarctic

    USGS Publications Warehouse

    U.S. Board on Geographic Names; U.S. Geological Survey; Defense Mapping Agency; National Science Foundation

    1995-01-01

    This gazetteer contains 12,710 names approved by the United States Board on Geographic Names and the Secretary of the Interior for features in Antarctica and the area extending northward to the Antarctic Convergence. Included in this geographic area, the Antarctic region, are the off-lying South Shetland Islands, the South Orkney Islands, the South Sandwich Islands, South Georgia, Bouvetøya, Heard Island, and the Balleny Islands. These names have been approved for use by U.S. Government agencies. Their use by the Antarctic specialist and the public is highly recommended for the sake of accuracy and uniformity. This publication, which supersedes previous Board gazetteers or lists for the area, contains names approved as recently as December 1994. The basic name coverage of this gazetteer corresponds to that of maps at the scale of 1:250,000 or larger for coastal Antarctica, the off-lying islands, and isolated mountains and ranges of the continent. Much of the interior of Antarctica is a featureless ice plateau. That area has been mapped at a smaller scale and is nearly devoid of toponyms. All of the names are for natural features, such as mountains, glaciers, peninsulas, capes, bays, islands, and subglacial entities. The names of scientific stations have not been listed alphabetically, but they may appear in the texts of some decisions. For the names of submarine features, reference should be made to the Gazetteer of Undersea Features, 4th edition, U.S. Board on Geographic Names, 1990.

  9. Formax Preserved Birds

    ERIC Educational Resources Information Center

    Sheridan, Philip

    1978-01-01

    A quick, simple method for preserving bird specimens using borax and a formalin solution is described. Procedures for injecting and mounting the specimens are given along with certain restrictions on preserving specimens. (MA)

  10. Angry Birds in Space

    NASA Video Gallery

    Aboard the International Space Station, Flight Engineer Don Pettit of NASA created a video using Angry Birds Space to explain how physics works in space, including demonstrating trajectories in mic...

  11. Awesome Audubon Birds

    ERIC Educational Resources Information Center

    Kahler, Laura

    2010-01-01

    In this article, the author describes a watercolor art lesson on Audubon birds. She also discusses how science, technology, writing skills, and the elements and principles of art can be incorporated into the lesson.

  12. Europe's last Mesozoic bird

    NASA Astrophysics Data System (ADS)

    Dyke, Gareth; Dortangs, Rudi; Jagt, John; Mulder, Eric; Schulp, Anne; Chiappe, Luis

    2002-08-01

    Birds known from more than isolated skeletal elements are rare in the fossil record, especially from the European Mesozoic. This paucity has hindered interpretations of avian evolution immediately prior to, and in the aftermath of, the Cretaceous-Tertiary (K-T) extinction event. We report on a specimen of a large ornithurine bird (closely related to Ichthyornis) from the uppermost Cretaceous (Maastricht Formation) of Belgium. This is the first record of a bird from these historic strata and the only phylogenetically informative ornithurine to be recovered from the Mesozoic of Europe. Because this new specimen was collected from 40 m below the K-T boundary (approximate age of 65.8 Ma), it is also the youngest non-neornithine (=non-modern) bird known from anywhere in the world.

  13. Angry Birds Space Encounter

    NASA Video Gallery

    At NASA's Kennedy Space Center Visitor Complex in Florida, a grand opening celebration was held for the new Angry Birds Space Encounter, March 22. Finland-based Rovio Entertainment, the creator of ...

  14. Bird Vision System

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Bird Vision system is a multicamera photogrammerty software application that runs on a Microsoft Windows XP platform and was developed at Kennedy Space Center by ASRC Aerospace. This software system collects data about the locations of birds within a volume centered on the Space Shuttle and transmits it in real time to the laptop computer of a test director in the Launch Control Center (LCC) Firing Room.

  15. Osteological and Soft-Tissue Evidence for Pneumatization in the Cervical Column of the Ostrich (Struthio camelus) and Observations on the Vertebral Columns of Non-Volant, Semi-Volant and Semi-Aquatic Birds

    PubMed Central

    Apostolaki, Naomi E.; Rayfield, Emily J.; Barrett, Paul M.

    2015-01-01

    Postcranial skeletal pneumaticity (PSP) is a condition most notably found in birds, but that is also present in other saurischian dinosaurs and pterosaurs. In birds, skeletal pneumatization occurs where bones are penetrated by pneumatic diverticula, membranous extensions that originate from air sacs that serve in the ventilation of the lung. Key questions that remain to be addressed include further characterizing (1) the skeletal features that can be used to infer the presence/absence and extent of PSP in birds and non-avian dinosaurs, and (2) the association between vertebral laminae and specific components of the avian respiratory system. Previous work has used vertebral features such as pneumatic foramina, fossae, and laminae to identify/infer the presence of air sacs and diverticula, and to discuss the range of possible functions of such features. Here, we tabulate pneumatic features in the vertebral column of 11 avian taxa, including the flightless ratites and selected members of semi-volant and semi-aquatic Neornithes. We investigate the associations of these osteological features with each other and, in the case of Struthio camelus, with the specific presence of pneumatic diverticula. We find that the mere presence of vertebral laminae does not indicate the presence of skeletal pneumaticity, since laminae are not always associated with pneumatic foramina or fossae. Nevertheless, laminae are more strongly developed when adjacent to foramina or fossae. In addition, membranous air sac extensions and adjacent musculature share the same attachment points on the vertebrae, rendering the use of such features for reconstructing respiratory soft tissue features ambiguous. Finally, pneumatic diverticula attach to the margins of laminae, foramina, and/or fossae prior to their intraosseous course. Similarities in PSP distribution among the examined taxa are concordant with their phylogenetic interrelationships. The possible functions of PSP are discussed in brief, based

  16. A Field Guide to Common Educator Birds.

    ERIC Educational Resources Information Center

    Smock, Judith N.

    1990-01-01

    Teaching may be for the birds, but many educator birds have been abandoning the field of late for downier nests. Several species still remain, including the crown-tufted superintendent bird, the red-throated assistant superintendent bird, the crested fly-catcher principal bird, the exotic scenery bird, the roadrunner psychologist bird, and the…

  17. Antarctic Meteorite Newsletter, Volume 28, Number 2

    NASA Technical Reports Server (NTRS)

    Righter, Kevin (Editor); Satterwhite, Cecilia (Editor)

    2005-01-01

    This newsletter contains classifications for 274 new meteorites from the 2003 and 2004 ANtarctic Search for METeorites (ANSMET) collections. They include samples from the Cumulus Hills, Larkman Nunatak, LaPaz Ice Field, MacAlpine Hills, Dominion Range, Miller Range, Roberts Massif, and Sandford Cliffs. Tables are provided of the newly classified Antarctic meteorites, meteorites classified by type, and tentative pairings petrographic descriptions.

  18. Aerodynamics of bird flight

    NASA Astrophysics Data System (ADS)

    Dvořák, Rudolf

    2016-03-01

    Unlike airplanes birds must have either flapping or oscillating wings (the hummingbird). Only such wings can produce both lift and thrust - two sine qua non attributes of flying.The bird wings have several possibilities how to obtain the same functions as airplane wings. All are realized by the system of flight feathers. Birds have also the capabilities of adjusting the shape of the wing according to what the immediate flight situation demands, as well as of responding almost immediately to conditions the flow environment dictates, such as wind gusts, object avoidance, target tracking, etc. In bird aerodynamics also the tail plays an important role. To fly, wings impart downward momentum to the surrounding air and obtain lift by reaction. How this is achieved under various flight situations (cruise flight, hovering, landing, etc.), and what the role is of the wing-generated vortices in producing lift and thrust is discussed.The issue of studying bird flight experimentally from in vivo or in vitro experiments is also briefly discussed.

  19. Cats protecting birds revisited.

    PubMed

    Fan, Meng; Kuang, Yang; Feng, Zhilan

    2005-09-01

    In this paper, we revisit the dynamical interaction among prey (bird), mesopredator (rat), and superpredator (cat) discussed in [Courchamp, F., Langlais, M., Sugihara, G., 1999. Cats protecting birds: modelling the mesopredator release effect. Journal of Animal Ecology 68, 282-292]. First, we develop a prey-mesopredator-superpredator (i.e., bird-rat-cat, briefly, BRC) model, where the predator's functional responses are derived based on the classical Holling's time budget arguments. Our BRC model overcomes several model construction problems in Courchamp et al. (1999), and admits richer, reasonable and realistic dynamics. We explore the possible control strategies to save or restore the bird by controlling or eliminating the rat or the cat when the bird is endangered. We establish the existence of two types of mesopredator release phenomena: severe mesopredator release, where once superpredators are suppressed, a burst of mesopredators follows which leads their shared prey to extinction; and mild mesopredator release, where the mesopredator release could assert more negative impact on the endemic prey but does not lead the endemic prey to extinction. A sharp sufficient criterion is established for the occurrence of severe mesopredator release. We also show that, in a prey-mesopredator-superpredator trophic food web, eradication of introduced superpredators such as feral domestic cats in the BRC model, is not always the best solution to protect endemic insular prey. The presence of a superpredator may have a beneficial effect in such systems. PMID:15998496

  20. Chemistry of the Antarctic stratosphere

    NASA Technical Reports Server (NTRS)

    Mcelroy, Michael B.; Salawitch, Ross J.; Wofsy, Steven C.

    1988-01-01

    Interferometric measurements of HCl, ClNO3, HNO3, NO2, and NO obtained over the Antarctic in 1986 are used to model the chemistry of the atmosphere in the region of the Ozone Hole. The low abundance noted in stratospheric HCl is attributed to incorporation of HCl in polar stratospheric clouds and subsequent reaction of HCl with ClNO3. The results point to a net loss of HNO3 from the stratosphere and to the suppression of the abundance of odd nitrogen at high altitudes in the vortex. O3 loss is suggested to be due to the catalytic influence of halogen radicals.

  1. Antibiotic resistance in wild birds

    PubMed Central

    Bonnedahl, Jonas

    2014-01-01

    Wild birds have been postulated as sentinels, reservoirs, and potential spreaders of antibiotic resistance. Antibiotic-resistant bacteria have been isolated from a multitude of wild bird species. Several studies strongly indicate transmission of resistant bacteria from human rest products to wild birds. There is evidence suggesting that wild birds can spread resistant bacteria through migration and that resistant bacteria can be transmitted from birds to humans and vice versa. Through further studies of the spatial and temporal distribution of resistant bacteria in wild birds, we can better assess their role and thereby help to mitigate the increasing global problem of antibiotic resistance. PMID:24697355

  2. Conservation and the Antarctic environment: the working group reports of the joint IUCN/SCAR symposium on the scientific requirements for Antarctic conservation

    SciTech Connect

    Bonner, W.N.; Angel, M.V.

    1987-01-01

    Six working groups were set up at the joint IUCN/SCAR Symposium on the scientific requirements for Antarctic conservation. These were charged with (i) identifying gaps in the scientific understanding of ecosystems that inhibit rational management, and (ii) considering whether present conservation practices were taking enough account of what is known of the region, particularly with regard to protected areas. There is still a need for synthesis and further work on stocks and the life history of krill in the pelagic ecosystem. Studies of crabeater seals deserve priority. The network of existing protected areas is inadequate for preserving all species of birds, seals and whales; new criteria are needed for effective conservation. On land, the Agreed Measures provide an adequate framework for conservation, though additional steps are needed to ensure adherence to their provisions. Selection criteria are deficient and additional measures are required. Commercial mineral exploitation in the Antarctic is a long way in the future but exploitation could result from political motives. There is a need for a data base for the design of investigations and impact assessment. Operational hazards need to be modelled in advance. The relevance of existing drilling technology (both for mining and for deep stratographical information) onshore and offshore, and the applicability of Arctic experience to future operations in the Antarctic need to be assessed. Operational hazards, such as icebergs, pressures encountered while drilling, well blow-outs, and oil spills, need to the anticipated and modelled in advance.

  3. [Birds' sense of direction].

    PubMed

    Hohtola, Esa

    2016-01-01

    Birds utilize several distinct sensory systems in a flexible manner in their navigation. When navigating with the help of landmarks, location of the sun and stars, or polarization image of the dome of the sky, they resort to vision. The significance of olfaction in long-range navigation has been under debate, even though its significance in local orientation is well documented. The hearing in birds extends to the infrasound region. It has been assumed that they are able to hear the infrasounds generated in the mountains and seaside and navigate by using them. Of the senses of birds, the most exotic one is the ability to sense magnetic fields of the earth. PMID:27522832

  4. Rabbits killing birds revisited.

    PubMed

    Zhang, Jimin; Fan, Meng; Kuang, Yang

    2006-09-01

    We formulate and study a three-species population model consisting of an endemic prey (bird), an alien prey (rabbit) and an alien predator (cat). Our model overcomes several model construction problems in existing models. Moreover, our model generates richer, more reasonable and realistic dynamics. We explore the possible control strategies to save or restore the bird by controlling or eliminating the rabbit or the cat when the bird is endangered. We confirm the existence of the hyperpredation phenomenon, which is a big potential threat to most endemic prey. Specifically, we show that, in an endemic prey-alien prey-alien predator system, eradication of introduced predators such as the cat alone is not always the best solution to protect endemic insular prey since predator control may fail to protect the indigenous prey when the control of the introduced prey is not carried out simultaneously. PMID:16529776

  5. Biomechanics of bird flight.

    PubMed

    Tobalske, Bret W

    2007-09-01

    Power output is a unifying theme for bird flight and considerable progress has been accomplished recently in measuring muscular, metabolic and aerodynamic power in birds. The primary flight muscles of birds, the pectoralis and supracoracoideus, are designed for work and power output, with large stress (force per unit cross-sectional area) and strain (relative length change) per contraction. U-shaped curves describe how mechanical power output varies with flight speed, but the specific shapes and characteristic speeds of these curves differ according to morphology and flight style. New measures of induced, profile and parasite power should help to update existing mathematical models of flight. In turn, these improved models may serve to test behavioral and ecological processes. Unlike terrestrial locomotion that is generally characterized by discrete gaits, changes in wing kinematics and aerodynamics across flight speeds are gradual. Take-off flight performance scales with body size, but fully revealing the mechanisms responsible for this pattern awaits new study. Intermittent flight appears to reduce the power cost for flight, as some species flap-glide at slow speeds and flap-bound at fast speeds. It is vital to test the metabolic costs of intermittent flight to understand why some birds use intermittent bounds during slow flight. Maneuvering and stability are critical for flying birds, and design for maneuvering may impinge upon other aspects of flight performance. The tail contributes to lift and drag; it is also integral to maneuvering and stability. Recent studies have revealed that maneuvers are typically initiated during downstroke and involve bilateral asymmetry of force production in the pectoralis. Future study of maneuvering and stability should measure inertial and aerodynamic forces. It is critical for continued progress into the biomechanics of bird flight that experimental designs are developed in an ecological and evolutionary context. PMID:17766290

  6. LiteBIRD

    NASA Astrophysics Data System (ADS)

    Ishino, Hirokazu

    2016-07-01

    We present LiteBIRD, a satellite project dedicated for the detection of the CMB B-mode polarization. The purpose of LiteBIRD is to measure the tensor-to-scalar ratio r with a precision of σr < 0.001 to test large-single-field slow-roll inflation models by scanning all the sky area for three years at the sun-earth L2 with the sensitivity of 3.2μKṡarcmin. We report an overview and the status of the project, including the ongoing detector and systematic studies.

  7. Underwater Optics in Sub-Antarctic and Antarctic Coastal Ecosystems

    PubMed Central

    Huovinen, Pirjo; Ramírez, Jaime; Gómez, Iván

    2016-01-01

    Understanding underwater optics in natural waters is essential in evaluating aquatic primary production and risk of UV exposure in aquatic habitats. Changing environmental conditions related with global climate change, which imply potential contrasting changes in underwater light climate further emphasize the need to gain insights into patterns related with underwater optics for more accurate future predictions. The present study evaluated penetration of solar radiation in six sub-Antarctic estuaries and fjords in Chilean North Patagonian region (39–44°S) and in an Antarctic bay (62°S). Based on vertical diffuse attenuation coefficients (Kd), derived from measurements with a submersible multichannel radiometer, average summer UV penetration depth (z1%) in these water bodies ranged 2–11 m for UV-B (313 nm), 4–27 m for UV-A (395 nm), and 7–30 m for PAR (euphotic zone). UV attenuation was strongest in the shallow Quempillén estuary, while Fildes Bay (Antarctica) exhibited the highest transparency. Optically non-homogeneous water layers and seasonal variation in transparency (lower in winter) characterized Comau Fjord and Puyuhuapi Channel. In general, multivariate analysis based on Kd values of UV and PAR wavelengths discriminated strongly Quempillén estuary and Puyuhuapi Channel from other study sites. Spatial (horizontal) variation within the estuary of Valdivia river reflected stronger attenuation in zones receiving river impact, while within Fildes Bay a lower spatial variation in water transparency could in general be related to closeness of glaciers, likely due to increased turbidity through ice-driven processes. Higher transparency and deeper UV-B penetration in proportion to UV-A/visible wavelengths observed in Fildes Bay suggests a higher risk for Antarctic ecosystems reflected by e.g. altered UV-B damage vs. photorepair under UV-A/PAR. Considering that damage repair processes often slow down under cool temperatures, adverse UV impact could be

  8. Underwater Optics in Sub-Antarctic and Antarctic Coastal Ecosystems.

    PubMed

    Huovinen, Pirjo; Ramírez, Jaime; Gómez, Iván

    2016-01-01

    Understanding underwater optics in natural waters is essential in evaluating aquatic primary production and risk of UV exposure in aquatic habitats. Changing environmental conditions related with global climate change, which imply potential contrasting changes in underwater light climate further emphasize the need to gain insights into patterns related with underwater optics for more accurate future predictions. The present study evaluated penetration of solar radiation in six sub-Antarctic estuaries and fjords in Chilean North Patagonian region (39-44°S) and in an Antarctic bay (62°S). Based on vertical diffuse attenuation coefficients (Kd), derived from measurements with a submersible multichannel radiometer, average summer UV penetration depth (z1%) in these water bodies ranged 2-11 m for UV-B (313 nm), 4-27 m for UV-A (395 nm), and 7-30 m for PAR (euphotic zone). UV attenuation was strongest in the shallow Quempillén estuary, while Fildes Bay (Antarctica) exhibited the highest transparency. Optically non-homogeneous water layers and seasonal variation in transparency (lower in winter) characterized Comau Fjord and Puyuhuapi Channel. In general, multivariate analysis based on Kd values of UV and PAR wavelengths discriminated strongly Quempillén estuary and Puyuhuapi Channel from other study sites. Spatial (horizontal) variation within the estuary of Valdivia river reflected stronger attenuation in zones receiving river impact, while within Fildes Bay a lower spatial variation in water transparency could in general be related to closeness of glaciers, likely due to increased turbidity through ice-driven processes. Higher transparency and deeper UV-B penetration in proportion to UV-A/visible wavelengths observed in Fildes Bay suggests a higher risk for Antarctic ecosystems reflected by e.g. altered UV-B damage vs. photorepair under UV-A/PAR. Considering that damage repair processes often slow down under cool temperatures, adverse UV impact could be further

  9. Birds of Prey.

    ERIC Educational Resources Information Center

    Irwin, Harriet

    Introducing students to different hawks and owls found in Wisconsin and building a basis for appreciation of these birds in their own environment is the purpose of this teacher's guide. Primarily geared for upper elementary and junior high grades, the concepts presented could be used in conjunction with the study of ecology. A filmstrip is…

  10. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... been vaccinated with with a vaccine for the H5 or H7 subtype of avian influenza; (5) That Newcastle...) of this subchapter as a region where highly pathogenic avian influenza exists; and (7) That the birds... vaccine for the H5 or H7 subtype of avian influenza; (6) That Newcastle disease did not occur anywhere...

  11. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... been vaccinated with with a vaccine for the H5 or H7 subtype of avian influenza; (5) That Newcastle...) of this subchapter as a region where highly pathogenic avian influenza exists; and (7) That the birds... vaccine for the H5 or H7 subtype of avian influenza; (6) That Newcastle disease did not occur anywhere...

  12. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... been vaccinated with with a vaccine for the H5 or H7 subtype of avian influenza; (5) That Newcastle...) of this subchapter as a region where highly pathogenic avian influenza exists; and (7) That the birds... vaccine for the H5 or H7 subtype of avian influenza; (6) That Newcastle disease did not occur anywhere...

  13. Eating Like a Bird.

    ERIC Educational Resources Information Center

    Brothers, Chris; Fortner, Rosanne W.

    This teacher guide and student workbook set contains two learning activities, designed for fifth through ninth grade students, that concentrate on the adaptations of shorebird beaks for a variety of habitats and food sources, and the effect of toxic chemicals in the food chain on the birds. In activity A, students discover how shorebirds are…

  14. Birds. Nature Discovery I.

    ERIC Educational Resources Information Center

    Stone, Sally F.

    The birds of New England and their particular habitats are explored in this guide which is part of a series of Nature Discovery publications. The materials are designed to directly supplement the natural science curricula and to complement other subject areas including social studies, language arts, music, and art. The program is designed for…

  15. Fish, birds and flies

    NASA Astrophysics Data System (ADS)

    Gibbings, J. C.

    2013-04-01

    The article in your animal physics special issue on the use of magnetic field sensing in bird navigation (November 2012 pp38-42) reminded me of a comment made regarding a paper that I presented in the US many years ago.

  16. Bird community composition

    USGS Publications Warehouse

    Antrobus, T.J.; Guilfoyle, M.P.; Barrow, W.C., Jr.; Hamel, P.B.; Wakeley, J.S.

    2000-01-01

    Neotropical migrants are birds that breed in North America and winter primarily in Central and South America. Long-term population studies of birds in the Eastern United States indicated declines of some forest-dwelling birds, many of which winter in the Neotropics (Peterjohn and others 1995). These declines were attributed to loss of wintering and breeding habitat due to deforestation and fragmentation, respectively. Many species of Nearctic migrants--birds that breed in the northern regions of North America and winter in the Southern United States--are also experiencing population declines. Because large areas of undistrubed, older, bottomland hardwood forests oftern contain large numbers of habitat specialists, including forest-interior neotropical migrants and wintering Nearctic migrants, these forests may be critical in maintaining avian diversity. This study had two primary objectivs: (1) to create a baseline data set that can be used as a standard against which other bottomland hardwood forests can be compared, and (2) to establish long-term monitoring stations during both breeding and wintering seasons to discern population trends of avian species using bottomland hardwood forests.

  17. Microbial ecology of Antarctic aquatic systems.

    PubMed

    Cavicchioli, Ricardo

    2015-11-01

    The Earth's biosphere is dominated by cold environments, and the cold biosphere is dominated by microorganisms. Microorganisms in cold Southern Ocean waters are recognized for having crucial roles in global biogeochemical cycles, including carbon sequestration, whereas microorganisms in other Antarctic aquatic biomes are not as well understood. In this Review, I consider what has been learned about Antarctic aquatic microbial ecology from 'omic' studies. I assess the factors that shape the biogeography of Antarctic microorganisms, reflect on some of the unusual biogeochemical cycles that they are associated with and discuss the important roles that viruses have in controlling ecosystem function. PMID:26456925

  18. A message to the antarctic community

    SciTech Connect

    Wilkness, P.E.

    1992-12-01

    Peter E. Wilkness, Division Director of the NSF Division of Polar Programs, summarizes the advances and changes in support of the US Antarctic Program over the last decade. Antarctic research has emerged as a vital component of global environmental concerns. Unique opportunities for astronomers and astrophysicists are found in the Antarctic. Logistic support and operational capabilities have been enhanced and the US stations have been renovated or replaced. Improved environmental management, both in terms of clean-up and current activities, is well under way. The challenge lies in managing and using these new tools in response to the public expectation of public benefit.

  19. Birds of Prey of Wisconsin.

    ERIC Educational Resources Information Center

    Hamerstrom, Frances

    This copiously illustrated document is designed to be a field quide to birds of prey that are common to Wisconsin, as well as to some that enter the state occasionally. An introduction discusses birds of prey with regard to migration patterns, the relationship between common names and the attitudes of people toward certain birds, and natural signs…

  20. Science Is for the Birds

    ERIC Educational Resources Information Center

    Potenza, Susan Ade

    2007-01-01

    In this article, the author discusses a five-month interdisciplinary bird study that she designed for her seventh-grade students that combines life science, technology, writing, art, mathematics, social studies and literature. The driving force behind this yearly unit is the BirdSleuth eBird program (formerly the Cornell University Classroom…

  1. Birding--Fun and Science

    ERIC Educational Resources Information Center

    McIntosh, Phyllis

    2014-01-01

    This feature article presents the basics of birding, or bird watching, and discusses its appeal, especially to serious birders. A section on "citizen scientists" explains organizations that collect data on birds and describes projects they organize. Other sections discuss the legacy of John James Audubon and the bald eagle.

  2. Attracting Birds to Your Backyard.

    ERIC Educational Resources Information Center

    Joyce, Brian

    1994-01-01

    Discusses methods for drawing birds to outdoor education areas, including the use of wild and native vegetation. Lists specific garden plants suitable for attracting birds in each season. Includes a guide to commercial bird seed and instructions for building homemade birdfeeders and nestboxes. (LZ)

  3. Antarctic Ozone: Theory and Observation.

    NASA Astrophysics Data System (ADS)

    Salawitch, Ross Jay

    The amount of ozone observed in October over Antarctica has fallen steadily and precipitously in the last decade. Observational data describing the phenomenology of the Antarctic ozone reduction are reviewed, followed by the presentation of theories that seek to account for the observed ozone reductions while satisfying other available constraints. We begin with a discussion of the thermodynamic properties of solid phases containing HCl and HNO_3. The presence of clouds in the Antarctic stratosphere, caused be extremely low temperatures during spring, leads to condensation and precipitation of HNO_3, and condensation and reaction of HCl. Both processes lead to the conversion of unreactive forms of chlorine to chlorine oxides, which participate in a sequence of chemical reactions that consume ozone. A chemical model that incorporates the influence of cloud catalyzed heterogeneous reactions is compared in detail to the interferometric measurements of HCl, ClNO_3, HNO_3 , NO_2, and NO obtained over Antarctica during the spring of 1986 (Farmer et al., 1987). Model results are consistent with observed temporal trends of these species and with trends for total column ozone reported by Stolarski et al. (1986). Loss of ozone is attributed to the catalytic influence of chlorine and bromine radicals, in cycles suggested by McElroy et al. (1986b) and Molina and Molina (1987). Constraints are then placed on the abundance of stratospheric bromine by analysis of observations of OClO over Antarctica during the spring of 1986 (Solomon et al., 1987a). The diurnal variation of OClO is consistent with 16 +/- 4 ppt of stratospheric bromine if a fraction of the overall ClO + BrO reaction proceeds through a channel resulting in the production of BrCl. Bromine levels in this range would contribute approximately 20% of the total ozone loss. Finally, it is shown that the production of reactive chlorine oxides by heterogeneous processes depends on the initial concentration of HCl relative

  4. Carbonate Deposition on Antarctic Shelves

    NASA Astrophysics Data System (ADS)

    Frank, T. D.; James, N. P.; Malcolm, I.

    2011-12-01

    Limestones associated with glaciomarine deposits occur throughout the geologic record but remain poorly understood. The best-described examples formed during major ice ages of the Neoproterozoic and Late Paleozoic. Quaternary analogs on Antarctic shelves have received comparatively little study. Here, we report on the composition, spatial distribution, and stratigraphic context of carbonate sediments contained in piston cores from the Ross Sea. The goals of this work are to (1) document the nature and distribution of carbonate sediments on the Ross Sea continental shelf and (2) examine temporal relationships to Quaternary glaciation. Results will be used to develop criteria that will improve understanding of analogous deposits in the ancient record. All carbonate-rich intervals in piston cores from the Ross Rea, now housed at the Antarctic Marine Geology Research Facility at Florida State University, were examined and described in detail. Sediment samples were disaggregated and sieved into size fractions before description with paleontological analysis carried out on the coarsest size fraction (>250 microns). Carbonate-rich sediments are concentrated in the northwestern Ross Sea, along the distal margins of Mawson and Pennell Banks. Calcareous facies include a spectrum of lithologies that range from fossiliferous mud, sand, and gravel to skeletal floatstone-rudstone and bafflestone. Floatstone-rudstone and bafflestone is most abundant along western-facing slopes in areas protected from the Antarctic Coastal Current. Sand-prone facies dominate the tops of banks and mud-prone, often spicultic, facies occur in deeper areas. The carbonate factory is characterized by a low-diversity, heterozoan assemblage that is dominated by stylasterine hydrocorals, barnacles, and bryozoans. Molluscs and echinoids are present but not abundant. Planktic and benthic foraminifera are ubiquitous components of the sediment matrix, which is locally very rich in sponge spicules. Biota rarely

  5. Unveiling the Antarctic subglacial landscape.

    NASA Astrophysics Data System (ADS)

    Warner, Roland; Roberts, Jason

    2010-05-01

    Better knowledge of the subglacial landscape of Antarctica is vital to reducing uncertainties regarding prediction of the evolution of the ice sheet. These uncertainties are associated with bedrock geometry for ice sheet dynamics, including possible marine ice sheet instabilities and subglacial hydrological pathways (e.g. Wright et al., 2008). Major collaborative aerogeophysics surveys motivated by the International Polar Year (e.g. ICECAP and AGAP), and continuing large scale radar echo sounding campaigns (ICECAP and NASA Ice Bridge) are significantly improving the coverage. However, the vast size of Antarctica and logistic difficulties mean that data gaps persist, and ice thickness data remains spatially inhomogeneous. The physics governing large scale ice sheet flow enables ice thickness, and hence bedrock topography, to be inferred from knowledge of ice sheet surface topography and considerations of ice sheet mass balance, even in areas with sparse ice thickness measurements (Warner and Budd, 2000). We have developed a robust physically motivated interpolation scheme, based on these methods, and used it to generate a comprehensive map of Antarctic bedrock topography, using along-track ice thickness data assembled for the BEDMAP project (Lythe et al., 2001). This approach reduces ice thickness biases, compared to traditional inverse distance interpolation schemes which ignore the information available from considerations of ice sheet flow. In addition, the use of improved balance fluxes, calculated using a Lagrangian scheme, eliminates the grid orientation biases in ice fluxes associated with finite difference methods (Budd and Warner, 1996, Le Brocq et al., 2006). The present map was generated using a recent surface DEM (Bamber et al., 2009, Griggs and Bamber, 2009) and accumulation distribution (van de Berg et al., 2006). Comparing our results with recent high resolution regional surveys gives confidence that all major subglacial topographic features are

  6. Denitrification in the Antarctic stratosphere

    NASA Technical Reports Server (NTRS)

    Salawitch, R. J.; Gobbi, G. P.; Wofsy, S. C.; Mcelroy, M. B.

    1989-01-01

    Rapid loss of ozone over Antarctica in spring requires that the abundance of gaseous nitric acid be very low. Precipitation of particulate nitric acid has been assumed to occur in association with large ice crystals, requiring significant removal of H2O and temperatures well below the frost point. However, stratospheric clouds exhibit a bimodal size distribution in the Antarctic atmosphere, with most of the nitrate concentrated in particles with radii of 1 micron or greater. It is argued here that the bimodal size distribution sets the stage for efficient denitrification, with nitrate particles either falling on their own or serving as nuclei for the condensation of ice. Denitrification can therefore occur without significant dehydration, and it is unnecessary for temperatures to drop significantly below the frost point.

  7. Understanding Antarctic Climate and Glacial History

    NASA Astrophysics Data System (ADS)

    DeConto, Rob; Escutia, Carlota

    2010-01-01

    First Antarctic Climate Evolution Symposium; Granada, Spain, 7-11 September 2009; Antarctic Climate Evolution (ACE; http://www.ace.scar.org), a scientific research project of the Scientific Committee on Antarctic Research and a core International Polar Year project, held its first international symposium in Spain in September 2009. ACE's mission is to facilitate the study of Antarctic climate and glacial history through integration of numerical modeling with geophysical and geological data. Nearly 200 international scientists from the fields of climate, ocean, and ice modeling joined geologists, geophysicists, and geochemists for 5 days of intense interaction. Oral sessions were plenary and were limited to allow time for poster viewing, discussion, and workshops (http://www.acegranada2009.com/).

  8. Conservation in the Antarctic and Subantarctic

    ERIC Educational Resources Information Center

    McKenzie, D.

    1972-01-01

    Discusses briefly the ecosystems which have existed for a long time in the Antarctic region. Article indicates unwise killing of animals in that region may disturb important ecosystems which is unsound for economic benefits over a longer period. (PS)

  9. Cryosphere: Antarctic ice growth and retreat

    NASA Astrophysics Data System (ADS)

    Evans, Jeffrey

    2015-08-01

    Antarctic Ice Sheet change during the last glacial cycle is unclear. The timing of moraine development in the Ross basin suggests that the ice sheet reached maximum thickness under the warming temperatures of the last termination.

  10. Update on Terrestrial Ages of Antarctic Meteorites

    NASA Technical Reports Server (NTRS)

    Welten, K. C.; Nishiizumi, K.; Caffee, M. W.

    2000-01-01

    Terrestial ages are presented for 70 Antarctic meteorites, based on cosmogenic Be-10, Al-26 and Cl-36 in the metal phase. Also, results of leaching experiments are discussed to study possible contamination of stony meteorites with atmospheric Be-10

  11. Formation of the 1988 Antarctic ozone hole

    SciTech Connect

    Krueger, A.J.; Stolarski, R.S.; Schoeberl, M.R. )

    1989-05-01

    The 1988 Antarctic ozone hole, as observed with the Nimbus 7 TOMS instrument, formed in August but failed to deepen significantly during September. The structure of the surrounding total ozone maxima also differed from the prior year. The 1987 total ozone pattern was pole centered and symmetrical. During 1988 a persistent strong wavenumber 1 perturbation in total ozone developed in August which resulted in displacement of the polar ozone minimum to the base of the Antarctic Peninsula. Subsequently, a series of transient events diminished and a larger scale decrease in polar total ozone began. The decrease lasted less than two weeks, resulting in a net change of only 25 DU compared with the nearly 100 DU decline observed during the same period in 1987. The minimum values remained roughly constant until October 19, 1988 and then increased rapidly. The 1988 Antarctic ozone hole subsequently drifted off the Antarctic continent in late October and dissipated in mid-November.

  12. Breakup of Pack Ice, Antarctic Ice Shelf

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Breakup of Pack Ice along the periphery of the Antarctic Ice Shelf (53.5S, 3.0E) produced this mosaic of ice floes off the Antarctic Ice Shelf. Strong offshore winds, probably associated with strong katabatic downdrafts from the interior of the continent, are seen peeling off the edges of the ice shelf into long filamets of sea ice, icebergs, bergy bits and growlers to flow northward into the South Atlantic Ocean. 53.5S, 3.0E

  13. Potential climate change effects on the habitat of antarctic krill in the weddell quadrant of the southern ocean.

    PubMed

    Hill, Simeon L; Phillips, Tony; Atkinson, Angus

    2013-01-01

    Antarctic krill is a cold water species, an increasingly important fishery resource and a major prey item for many fish, birds and mammals in the Southern Ocean. The fishery and the summer foraging sites of many of these predators are concentrated between 0° and 90°W. Parts of this quadrant have experienced recent localised sea surface warming of up to 0.2°C per decade, and projections suggest that further widespread warming of 0.27° to 1.08°C will occur by the late 21(st) century. We assessed the potential influence of this projected warming on Antarctic krill habitat with a statistical model that links growth to temperature and chlorophyll concentration. The results divide the quadrant into two zones: a band around the Antarctic Circumpolar Current in which habitat quality is particularly vulnerable to warming, and a southern area which is relatively insensitive. Our analysis suggests that the direct effects of warming could reduce the area of growth habitat by up to 20%. The reduction in growth habitat within the range of predators, such as Antarctic fur seals, that forage from breeding sites on South Georgia could be up to 55%, and the habitat's ability to support Antarctic krill biomass production within this range could be reduced by up to 68%. Sensitivity analysis suggests that the effects of a 50% change in summer chlorophyll concentration could be more significant than the direct effects of warming. A reduction in primary production could lead to further habitat degradation but, even if chlorophyll increased by 50%, projected warming would still cause some degradation of the habitat accessible to predators. While there is considerable uncertainty in these projections, they suggest that future climate change could have a significant negative effect on Antarctic krill growth habitat and, consequently, on Southern Ocean biodiversity and ecosystem services. PMID:23991072

  14. Potential Climate Change Effects on the Habitat of Antarctic Krill in the Weddell Quadrant of the Southern Ocean

    PubMed Central

    Hill, Simeon L.; Phillips, Tony; Atkinson, Angus

    2013-01-01

    Antarctic krill is a cold water species, an increasingly important fishery resource and a major prey item for many fish, birds and mammals in the Southern Ocean. The fishery and the summer foraging sites of many of these predators are concentrated between 0° and 90°W. Parts of this quadrant have experienced recent localised sea surface warming of up to 0.2°C per decade, and projections suggest that further widespread warming of 0.27° to 1.08°C will occur by the late 21st century. We assessed the potential influence of this projected warming on Antarctic krill habitat with a statistical model that links growth to temperature and chlorophyll concentration. The results divide the quadrant into two zones: a band around the Antarctic Circumpolar Current in which habitat quality is particularly vulnerable to warming, and a southern area which is relatively insensitive. Our analysis suggests that the direct effects of warming could reduce the area of growth habitat by up to 20%. The reduction in growth habitat within the range of predators, such as Antarctic fur seals, that forage from breeding sites on South Georgia could be up to 55%, and the habitat’s ability to support Antarctic krill biomass production within this range could be reduced by up to 68%. Sensitivity analysis suggests that the effects of a 50% change in summer chlorophyll concentration could be more significant than the direct effects of warming. A reduction in primary production could lead to further habitat degradation but, even if chlorophyll increased by 50%, projected warming would still cause some degradation of the habitat accessible to predators. While there is considerable uncertainty in these projections, they suggest that future climate change could have a significant negative effect on Antarctic krill growth habitat and, consequently, on Southern Ocean biodiversity and ecosystem services. PMID:23991072

  15. Ecological importance of the Southern Boundary of the Antarctic Circumpolar Current

    NASA Astrophysics Data System (ADS)

    Tynan, Cynthia T.

    1998-04-01

    The Southern Ocean surrounds the Antarctic continent and supports one of the most productive marine ecosystems. Migratory and endemic species of whales, seals and birds benefit from the high biomass of their principal prey, krill (Euphausia superba) and cephalopods, in this area. Most species of baleen whales and male sperm whales in the Southern Hemisphere migrate between low-latitude breeding grounds in winter and highly productive Antarctic feeding grounds in summer. Here I show the importance of the southernmost reaches of the strongest ocean current, the Antarctic Circumpolar Current (ACC), to a complex and predictable food web of the Southern Ocean. The circumpolar distributions of blue, fin and humpback whales from spring to midsummer trace the non-uniform high-latitude penetration of shoaled, nutrient-rich Upper Circumpolar Deep Water, which is carried eastward by the ACC. The poleward extent of this water mass delineates the Southern Boundary of the ACC and corresponds not only to the circumpolar distributions of baleen whales, but also to distributions of krill and to regions of high, seasonally averaged, phytoplankton biomass. Sperm whales, which feed on cephalopods, also congregate in highest densities near the Southern Boundary. The association of primary production, Krill, and whales with the Southern Boundary, suggests that it provides predictably productive foraging for many species, and is of critical importance to the function of the Southern Ocean ecosystem.

  16. Antarctic, Sub-Antarctic and cold temperate echinoid database

    PubMed Central

    Pierrat, Benjamin; Saucède, Thomas; Festeau, Alain; David, Bruno

    2012-01-01

    Abstract This database includes spatial data of Antarctic, Sub-Antarctic and cold temperate echinoid distribution (Echinodermata: Echinoidea) collected during many oceanographic campaigns led in the Southern Hemisphere from 1872 to 2010. The dataset lists occurrence data of echinoid distribution south of 35°S latitude, together with information on taxonomy (from species to genus level), sampling sources (cruise ID, sampling dates, ship names) and sampling sites (geographic coordinates and depth). Echinoid occurrence data were compiled from the Antarctic Echinoid Database (David et al. 2005a), which integrates records from oceanographic cruises led in the Southern Ocean until 2003. This database has been upgraded to take into account data from oceanographic cruises led after 2003. The dataset now reaches a total of 6160 occurrence data that have been checked for systematics reliability and consistency. It constitutes today the most complete database on Antarctic and Sub-Antarctic echinoids. PMID:22787419

  17. Threatened bird valuation in Australia.

    PubMed

    Zander, Kerstin K; Ainsworth, Gillian B; Meyerhoff, Jürgen; Garnett, Stephen T

    2014-01-01

    Threatened species programs need a social license to justify public funding. A contingent valuation survey of a broadly representative sample of the Australian public found that almost two thirds (63%) supported funding of threatened bird conservation. These included 45% of a sample of 645 respondents willing to pay into a fund for threatened bird conservation, 3% who already supported bird conservation in another form, and 15% who could not afford to pay into a conservation fund but who nevertheless thought that humans have a moral obligation to protect threatened birds. Only 6% explicitly opposed such payments. Respondents were willing to pay about AUD 11 annually into a conservation fund (median value), including those who would pay nothing. Highest values were offered by young or middle aged men, and those with knowledge of birds and those with an emotional response to encountering an endangered bird. However, the prospect of a bird going extinct alarmed almost everybody, even most of those inclined to put the interests of people ahead of birds and those who resent the way threatened species sometimes hold up development. The results suggest that funding for threatened birds has widespread popular support among the Australian population. Conservatively they would be willing to pay about AUD 14 million per year, and realistically about AUD 70 million, which is substantially more than the AUD 10 million currently thought to be required to prevent Australian bird extinctions. PMID:24955957

  18. Threatened Bird Valuation in Australia

    PubMed Central

    Zander, Kerstin K.; Ainsworth, Gillian B.; Meyerhoff, Jürgen; Garnett, Stephen T.

    2014-01-01

    Threatened species programs need a social license to justify public funding. A contingent valuation survey of a broadly representative sample of the Australian public found that almost two thirds (63%) supported funding of threatened bird conservation. These included 45% of a sample of 645 respondents willing to pay into a fund for threatened bird conservation, 3% who already supported bird conservation in another form, and 15% who could not afford to pay into a conservation fund but who nevertheless thought that humans have a moral obligation to protect threatened birds. Only 6% explicitly opposed such payments. Respondents were willing to pay about AUD 11 annually into a conservation fund (median value), including those who would pay nothing. Highest values were offered by young or middle aged men, and those with knowledge of birds and those with an emotional response to encountering an endangered bird. However, the prospect of a bird going extinct alarmed almost everybody, even most of those inclined to put the interests of people ahead of birds and those who resent the way threatened species sometimes hold up development. The results suggest that funding for threatened birds has widespread popular support among the Australian population. Conservatively they would be willing to pay about AUD 14 million per year, and realistically about AUD 70 million, which is substantially more than the AUD 10 million currently thought to be required to prevent Australian bird extinctions. PMID:24955957

  19. Health aspects of Antarctic tourism.

    PubMed

    Prociv, P

    1998-12-01

    Increasing numbers of seaborne tourists are visiting Antarctica, with most coming from the United States (3503 in 1996-97), Germany (777), and Australia (680; cf. 356 in 1994-95 and 410 in 1995-96). The impression among travel medicine clinicians is that, each year, more prospective travelers seek advice about the health demands of this type of adventure, mostly relating to fitness for travel, exposure to extreme cold, hazards in ice and snow, and other potential health risks. This is a recent phenomenon. While a regular shipping service had been established between the Falklands and the subantarctic islands of South Georgia and the South Shetlands by 1924, the first documented tourists accompanied an Argentine expedition to the South Orkneys in 1933.1 Commercial airline flights over these islands and the Antarctic Peninsula began in 1956, from Chile, and recreational cruises to the Peninsula began in 1958. Tourist numbers subsequently grew slowly, for what was clearly an exclusive and very expensive undertaking, with few ships available for these hazardous voyages. From 1957 to 1993, 37,000 tourists visited by sea, most seeing only the Peninsula.2 The dramatic recent growth in numbers is a consequence of the collapse of the Soviet Union. The small fleet of ice-strengthened research vessels and working icebreakers, which was made redundant by withdrawal of central government support from isolated communities and military activities along the northern coast of Siberia (and from Antarctic research bases), now accounts for the bulk of charter-cruise tourism to Antarctica, at competitive prices. According to the International Association of Antarctica Tour Operators,3 7322 people traveled to Antarctica on commercially organized voyages in the 1996-97 season, and a record 10,000 shipborne visitors were expected for the 1997-98 season (November-March), traveling mainly from South America to the Peninsula on 15 ice-reinforced vessels, each carrying between 36 and 180

  20. Controls and variability of solute and sedimentary fluxes in Antarctic and sub-Antarctic Environments

    NASA Astrophysics Data System (ADS)

    Zwolinski, Zbigniew

    2015-04-01

    The currently prepared SEDIBUD Book on "Source-to-Sink Fluxes in Undisturbed Cold Environments" (edited by Achim A. Beylich, John C. Dixon and Zbigniew Zwolinski and published by Cambridge University Press) is summarizing and synthesizing the achievements of the International Association of Geomorphologists` (I.A.G./A.I.G.) Working Group SEDIBUD (Sediment Budgets in Cold Environments), which has been active since 2005 (http://www.geomorph.org/wg/wgsb.html). The book comprises five parts. One of them is part about sub-Antarctic and Antarctic Environments. This part "Sub-Antarctic and Antarctic Environments" describes two different environments, namely oceanic and continental ones. Each part contains results of research on environmental drivers and rates of contemporary solute and sedimentary fluxes in selected sites. Apart from describing the environmental conditions of the whole continent of Antarctica and sub-Antarctic islands (Zb.Zwolinski, M.Kejna, A.N.Lastochkin, A.Zhirov, S.Boltramovich) this part of the book characterizes terrestrial polar oases free from multi-year ice and snow covers (Zb.Zwolinski). The detailed results of geoecological and sedimentological research come from different parts of Antarctica. Antarctic continental shelf (E.Isla) is an example of sub-Antarctic oceanic environment. South Shetlands, especially King George Island (Zb.Zwolinski, M.Kejna, G.Rachlewicz, I.Sobota, J.Szpikowski), is an example of sub-Antarctic terrestrial environment. Antarctic Peninsula (G.Vieira, M.Francelino, J.C.Fernandes) and surroundings of McMurdo Dry Valleys (W.B.Lyons, K.A.Welch, J.Levy, A.Fountain, D.McKnight) are examples of Antarctic continental environments. The key goals of the Antarctic and sub-Antarctic book chapters are following: (i) identify the main environmental drivers and rates of contemporary solute and sedimentary fluxes, and (ii) model possible effects of projected climate change on solute and sedimentary fluxes in cold climate environments

  1. Winter bird population studies and project prairie birds for surveying grassland birds

    USGS Publications Warehouse

    Twedt, D.J.; Hamel, P.B.; Woodrey, M.S.

    2008-01-01

    We compared 2 survey methods for assessing winter bird communities in temperate grasslands: Winter Bird Population Study surveys are area-searches that have long been used in a variety of habitats whereas Project Prairie Bird surveys employ active-flushing techniques on strip-transects and are intended for use in grasslands. We used both methods to survey birds on 14 herbaceous reforested sites and 9 coastal pine savannas during winter and compared resultant estimates of species richness and relative abundance. These techniques did not yield similar estimates of avian populations. We found Winter Bird Population Studies consistently produced higher estimates of species richness, whereas Project Prairie Birds produced higher estimates of avian abundance for some species. When it is important to identify all species within the winter bird community, Winter Bird Population Studies should be the survey method of choice. If estimates of the abundance of relatively secretive grassland bird species are desired, the use of Project Prairie Birds protocols is warranted. However, we suggest that both survey techniques, as currently employed, are deficient and recommend distance- based survey methods that provide species-specific estimates of detection probabilities be incorporated into these survey methods.

  2. 76 FR 9849 - Comprehensive Environmental Evaluations for Antarctic Activities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-22

    ... Comprehensive Environmental Evaluations for Antarctic Activities SUMMARY: The Department of State gives notice of the availability of two draft Comprehensive Environmental Evaluations (CEEs) for activities... Evaluation: Construction and Operation of Jang Bogo Antarctic Research Station, Terra Nova Bay,...

  3. Quantifying Antarctic marine biodiversity: The SCAR-MarBIN data portal

    NASA Astrophysics Data System (ADS)

    Griffiths, Huw J.; Danis, Bruno; Clarke, Andrew

    2011-03-01

    The documentation and analysis of broad-scale biological diversity requires modern databases. Here we describe the SCAR-Marine Biodiversity Information Network (SCAR-MarBIN) and demonstrate its value with a preliminary analysis of geographic patterns in species richness for a variety of marine taxa. SCAR-MarBIN is a web portal ( www.scarmarbin.be) that compiles and manages existing and new information on Antarctic marine biodiversity; it currently links over 140 datasets comprising over one million records. The portal is home to the Registry of Antarctic Marine Species (RAMS), an authoritative taxonomic list of marine species occurring in Antarctica. RAMS is a key resource for the Census of Antarctic Marine Life (CAML), a major five-year project that aims at assessing the nature, distribution and abundance of Southern Ocean biological diversity. SCAR-MarBIN provides a means of quantifying not only the diversity and distribution of Antarctic marine life but also a record of how, when and where these have been studied. It allows for the examination of geographic and bathymetric ranges, the documentation of gaps within and limits to the data, together with the identification of areas of particularly high diversity (hotspots) and also under-sampled regions or taxa. A preliminary analysis indicates that the pattern of sampling hotspots is driven principally by the pelagic data, mainly bird and mammal observations, whereas benthic species drive the overall pattern in species richness. Analyses of the complete data set reveal important biases in the data: most samples have been taken in shallow water (<700 m) and are either concentrated around shore-based research stations, or in the open ocean close to regular ship transit routes. These data provide a useful benchmark for the future, enabling ventures such as CAML to assess their impact on knowledge of biological diversity. It also highlights key areas for further investigation, such as the deep sea and the Amundsen Sea.

  4. Access to bird population data

    USGS Publications Warehouse

    Martin, E.; Peterjohn, B.G.; Koneff, M.D.

    2001-01-01

    Access to bird population data is critical for effective conservation planning and implementation. Although a tremendous volume of baseline data exists, it is often diffusely distributed and inaccessible to the resource manager and decision maker. A mechanism that facilitates assembly, documentation and delivery of avian data in a user-friendly manner is needed in order to integrate bird-related information resources across agencies and organizations. To address this fundamental need, the National Biological Information Infrastructure (NBII), in partnership with the U.S. Geological Survey's Patuxent Wildlife Research Center and the U.S. Fish and Wildlife Service, is developing a web-based interactive system that will focus on access to bird population and habitat data used in bird management and conservation. This system, known as the NBII Bird Conservation Node, will support planning and evaluation of bird conservation activities within the context of the North American Bird Conservation Initiative (NABCI), a framework for collaboration among organizations interested in bird conservation across North America. Initial development of the NBII Bird Conservation Node will focus on creating a prototype mapping application that will provide interactive access to data from the North American Breeding Bird Survey, the Colonial Waterbird Survey, the Breeding Waterfowl Population and Habitat Survey, and the Atlantic Flyway Mid-winter Waterfowl Survey. This prototype mapping application, to be available on-line at http://www.nbii.gov by Sep 2001, will lay the foundation for establishment of a Migratory Bird Data Center at Patuxent Wildlife Research Center, and will provide an opportunity for linking to and establishing partnerships with other sources of bird population and habitat data available over the Internet.

  5. Radar studies of bird migration

    NASA Technical Reports Server (NTRS)

    Williams, T. C.; Williams, J. M.

    1974-01-01

    Observations of bird migration with NASA radars were made at Wallops Island, Va. Simultaneous observations were made at a number of radar sites in the North Atlantic Ocean in an effort to discover what happened to those birds that were observed leaving the coast of North America headed toward Bermuda, the Caribbean and South America. Transatlantic migration, utilizing observations from a large number of radars is discussed. Detailed studies of bird movements at Wallops Island are presented.

  6. Cardiovascular control in Antarctic fish

    NASA Astrophysics Data System (ADS)

    Egginton, Stuart; Campbell, Hamish; Davison, William

    2006-04-01

    The capacity for synthesis and plasma levels of stress hormones in species with a range of activity patterns suggest that depressed catecholamine synthesis is typical of notothenioid fishes regardless of life style, although they are able to release extensive stores under conditions of extreme trauma. Cortisol does not appear to be an important primary stress hormone in these species. In general, vascular reactivity shows a modest α and β adrenergic tonus, but with greater potency for cholinergic and serotonergic vasoconstrictor agonists, although a dominance of vasodilatation over vasoconstriction is observed in one species. Vasomotor control mechanisms appear to be primarily a consequence of evolutionary lineage rather than low environmental temperature, but the pattern may be modified according to functional demand. These and other data confirm the cardiovascular system is dominated by cholinergic control: the heart apparently lacks adrenergic innervation, but receives inhibitory parasympathetic input that regulates heart rate (HR) by setting a resting vagal tonus. Oxygen consumption (MO 2) determined at rest and varied via specific dynamic action, in intact fish and fish that had undergone bilateral sectioning of the vagus nerve, show that HR is a good predictor of MO 2, and that the major influence on HR is the degree of vagal tone—these fish work by removing the brake rather than applying the accelerator. However, whether these traits actually represent adaptation to the Antarctic environment or merely represent ancestral characteristics and their relative phylogenetic position is at present unclear.

  7. 1980 breeding bird censuses

    SciTech Connect

    Raynor, G.S.

    1980-09-01

    As part of a program to characterize the plant and animal life of the Laboratory site and the surrounding region, the two breeding bird censuses originated in 1977 were continued in 1980. Coverage was below that of previous years due to illness and travel of some participants, but 11 trips were made to the BNL plot and 8 to the Westhampton plot. Each was censused by separate teams of three volunteer observers. The number of breeding species and number of territorial males on the BNL plot have progressively declined since 1977 but little change has taken place in either number of territories or species composition on the Westhampton plot.

  8. Avian evolution, Gondwana biogeography and the Cretaceous-Tertiary mass extinction event.

    PubMed Central

    Cracraft, J.

    2001-01-01

    The fossil record has been used to support the origin and radiation of modern birds (Neornithes) in Laurasia after the Cretaceous-Tertiary mass extinction event, whereas molecular clocks have suggested a Cretaceous origin for most avian orders. These alternative views of neornithine evolution are examined using an independent set of evidence, namely phylogenetic relationships and historical biogeography. Pylogenetic relationships of basal lineages of neornithines, including ratite birds and their allies (Palaleocognathae), galliforms and anseriforms (Galloanserae), as well as lineages of the more advanced Neoves (Gruiformes, (Capimulgiformes, Passeriformes and others) demonstrate pervasive trans-Antarctic distribution patterns. The temporal history of the neornithines can be inferred from fossil taxa and the ages of vicariance events, and along with their biogeographical patterns, leads to the conclusion that neornithines arose in Gondwana prior to the Cretaceous Tertiary extinction event. PMID:11296857

  9. 77 FR 31044 - Permits Issued Under the Antarctic Conservation Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ... Permits Issued Under the Antarctic Conservation Act AGENCY: National Science Foundation. ACTION: Notice of permits issued under the Antarctic Conservation of 1978, Public Law 95-541. SUMMARY: The National Science Foundation (NSF) is required to publish notice of permits issued under the Antarctic Conservation Act of...

  10. Alien invasive birds.

    PubMed

    Brochier, B; Vangeluwe, D; van den Berg, T

    2010-08-01

    A bird species is regarded as alien invasive if it has been introduced, intentionally or accidentally, to a location where it did not previously occur naturally, becomes capable of establishing a breeding population without further intervention by humans, spreads and becomes a pest affecting the environment, the local biodiversity, the economy and/or society, including human health. European Starling (Sturnus vulgaris), Common Myna (Acridotheres tristis) and Red-vented Bulbul (Pycnonotus cafer) have been included on the list of '100 of the World's Worst Invasive Alien Species', a subset of the Global Invasive Species Database. The 'Delivering Alien Invasive Species Inventories for Europe' project has selected Canada Goose (Branta canadensis), Ruddy Duck (Oxyura jamaicensis), Rose-ringed Parakeet (Psittacula krameri) and Sacred Ibis (Threskiornis aethiopicus) as among 100 of the worst invasive species in Europe. For each of these alien bird species, the geographic range (native and introduced range), the introduction pathway, the general impacts and the management methods are presented. PMID:20919578

  11. The Antarctic cryptoendolithic ecosystem: relevance to exobiology.

    PubMed

    Friedmann, E I; Ocampo-Friedmann, R

    1984-01-01

    Cryptoendolithic microorganisms in the Antarctic desert live inside porous sandstone rocks, protected by a thin rock crust. While the rock surface is abiotic, the microclimate inside the rock is comparatively mild. These organisms may have descended from early, pre-glaciation Antarctic life forms and thus may represent the last outpost of life in a gradually deteriorating environment. Assuming that life once arose on Mars, it is conceivable that, following the loss of water, the last of surviving organisms withdrew to similar insulated microenvironments. Because such microscopic pockets have little connection with the outside environment, their detection may be difficult. The chances that the Viking lander could sample cryptoendolithic microorganisms in the Antarctic desert would be infinitesimal. PMID:6462703

  12. The Antarctic cryptoendolithic ecosystem - Relevance to exobiology

    NASA Technical Reports Server (NTRS)

    Friedmann, E. I.; Ocampo-Friedmann, R.

    1984-01-01

    Cryptoendolithic microorganisms in the Antarctic desert live inside porous sandstone rocks, protected by a thin rock crust. While the rock surface is abiotic, the microclimate inside the rock is comparatively mild. These organisms may have descended from early, pre-glaciation Antarctic life forms and thus may represent the last outpost of life in a gradually deteriorating environment. Assuming that life once arose on Mars, it is conceivable that, following the loss of water, the last of surviving organisms withdrew to similar insulated microenvironments. Because such microscopic pockets have little connection with the outside environment, their detection may be difficult. The chances that the Viking lander could sample cryptoendolithic microorganisms in the Antarctic desert would be infinitesimal.

  13. Radar sensor for an autonomous Antarctic explorer

    NASA Astrophysics Data System (ADS)

    Foessel, Alex; Apostolopoulos, Dimi; Whittaker, William L.

    1999-01-01

    The localization and identification of antarctic meteorites is a task of great scientific interest and with implications to planetary exploration. Autonomous search for antarctic meteorites presents a profound technical challenge. Ground Penetrating Radar (GPR) holds the prospect to safeguard antarctic robot from terrain dangers and detect subsurface objects. In January 1998, we validated a 500 MHz GPR sensor as part of a field robotic technology demonstration at Patriot Hills, Antarctica. We deployed the sensor from a sled and integrate with position and attitude instruments to perform field measurements. Data was acquired under different conditions and in multiple locations. The radar detected hidden crevasses from 50 cm. distance, thus showing its merit as a rover safeguarding device. It also localized 5 cm. rocks ins now and ice. Moreover, the radar data was used to characterize snow/ice/bedrock stratigraphy. GPR position measurements enabled ground truth and mapping of the location of hazards and interesting subsurface objects and features.

  14. Antarctic sea ice and temperature variations

    SciTech Connect

    Walsh, J.E.; Zwally, H.J.; Weatherly, J.W.

    1992-03-01

    Monthly antarctic station temperatures are used in conjunction with grids of sea ice coverage in order to evaluate temporal trends and the strength of associations between the two variables at lags of up to several seasons. The trends of temperature are predominantly positive in winter and summer, but predominantly negative in spring. The spatially aggregated trend of temperature is small but positive, while the corresponding trend of ice coverage is small but negative. Cross-correlations between concurrent anomalies of the two variables are negative over most of the continent and are strongest over the Antarctic Peninsula, especially in winter. In regions other than the Antarctic Peninsula, lag correlations between seasonal anomalies are generally stronger with ice lagging the summer temperatures and with ice leading the winter temperatures.

  15. When Will the Antarctic Ozone Hole Recover?

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Stephen A.; Schauffler, Sue

    2006-01-01

    The Antarctic ozone hole demonstrates large-scale, man-made affects on our atmosphere. Surface observations now show that human produced ozone depleting substances (ODSs) are declining. The ozone hole should soon start to diminish because of this decline. Herein we demonstrate an ozone hole parametric model. This model is based upon: 1) a new algorithm for estimating C1 and Br levels over Antarctica and 2) late-spring Antarctic stratospheric temperatures. This parametric model explains 95% of the ozone hole area s variance. We use future ODS levels to predict ozone hole recovery. Full recovery to 1980 levels will occur in approximately 2068. The ozone hole area will very slowly decline over the next 2 decades. Detection of a statistically significant decrease of area will not occur until approximately 2024. We further show that nominal Antarctic stratospheric greenhouse gas forced temperature change should have a small impact on the ozone hole.

  16. When Will the Antarctic Ozone Hole Recover?

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.

    2006-01-01

    The Antarctic ozone hole demonstrates large-scale, man-made affects on our atmosphere. Surface observations now show that human produced ozone depleting substances (ODSs) are declining. The ozone hole should soon start to diminish because of this decline. In this talk we will demonstrate an ozone hole parametric model. This model is based upon: 1) a new algorithm for estimating 61 and Br levels over Antarctica and 2) late-spring Antarctic stratospheric temperatures. This parametric model explains 95% of the ozone hole area's variance. We use future ODS levels to predict ozone hole recovery. Full recovery to 1980 levels will occur in approximately 2068. The ozone hole area will very slowly decline over the next 2 decades. Detection of a statistically significant decrease of area will not occur until approximately 2024. We further show that nominal Antarctic stratospheric greenhouse gas forced temperature change should have a small impact on the ozone hole.

  17. Tuberculosis in wild birds: implications for captive birds

    USGS Publications Warehouse

    Converse, K. A.; Dein, F. J.

    1990-01-01

    The geographic distribution of avian tuberculosis is widespread but the lack of visible epizootics makes assessment of its impact on wild birds difficult. Generally a low prevalence, widely-scattered, individual animal disease, avian tuberculosis is caused by the same agent in wild and domestic birds. Thus there exists the potential for disease transfer between these two groups in situations that result in direct contact such as wild animals newly captured or transferred from rehabilitation centers, and wild and captive animals intermingling in exhibit areas. During the past 7 yr, tuberculosis caused by Mycobacterium avium, was diagnosed in 64 birds submitted to the National Wildlife Health Research Center from 16 states; avian tuberculosis was the primary diagnosis in 52 of the 64 birds, while the remaining 12 isolates were incidental findings. Twenty-eight of these birds were picked up during epizootics caused by other disease agents including avian cholera, botulism type C, and lead, organophosphorus compound, and cyanide poisoning. Twelve birds were found incidental to birds collected during disease monitoring programs and research projects, and 10 birds were collected by hunters or found sick and euthanatized. Tuberculosis lesions occurred (in order of decreasing frequency) in the liver, intestine, spleen, lung, and air sacs. Several unusual morphological presentations were observed in the gizzard, shoulder joint, jugular vein, face, nares and bill, ureter and bone marrow. Infected birds were collected during all 12 mo of the yr from a variety of species in the Anseriformes, Podicipediformes, Gruiformes, and Falconiformes. Nine of the 46 known age birds were immature indicating that lesions can develop during the first year.

  18. FAQ: West Nile Virus and Dead Birds

    MedlinePlus

    ... Education Public Service Videos West Nile Virus & Dead Birds Recommend on Facebook Tweet Share Compartir On this ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...

  19. Bird Migration Echoes Observed by Polarimetric Radar

    NASA Astrophysics Data System (ADS)

    Minda, Haruya; Furuzawa, Fumie A.; Satoh, Shinsuke; Nakamura, Kenji

    A C-band polarimetric radar on Okinawa Island successfully observed large-scale bird migrations over the western Pacific Ocean. The birds generated interesting polarimetric signatures. This paper describes the signatures and speculates bird behavior.

  20. Antarctic Meteorite Newsletter, Volume 8, Number 2

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Requests for samples are welcomed from research scientists of all countries, regardless of their current state of funding for meteorite studies. All sample requests will be reviewed by the Meteorite Working Group (MWG), a peer-review committee that guides the collection, curation, allocation, and distribution of the U.S. Antarctic meteorites. Issurance of samples does not imply a commitment by any agency to fund the proposed research. Requests for financial support must be submitted separately to the appropriate funding agencies. As a matter of policy, U.S. Antarctic meteorites are the property of the National Science Foundation and all allocations are subject to recall.

  1. First geomagnetic measurements in the Antarctic region

    NASA Astrophysics Data System (ADS)

    Raspopov, O. M.; Demina, I. M.; Meshcheryakov, V. V.

    2014-05-01

    Based on data from literature and archival sources, we have further processed and analyzed the results of geomagnetic measurements made during the 1772-1775 Second World Expedition by James Cook and the 1819-1821 overseas Antarctic Expedition by Russian mariners Bellingshausen and Lazarev. Comparison with the GUFM historical model showed that there are systematic differences in the spatial structure of both the declination and its secular variation. The results obtained can serve as a basis for the construction of regional models of the geomagnetic field for the Antarctic region.

  2. Primary Production in Antarctic Sea Ice

    NASA Technical Reports Server (NTRS)

    Arrigo, Kevin R.; Worthen, Denise L.; Lizotte, Michael P.; Dixon, Paul; Dieckmann, Gerhard

    1997-01-01

    A numerical model shows that in Antarctic sea ice, increased flooding in regions with thick snow cover enhances primary production in the infiltration (surface) layer. Productivity in the freeboard (sea level) layer is also determined by sea ice porosity, which varies with temperature. Spatial and temporal variation in snow thickness and the proportion of first-year ice thus determine regional differences in sea ice primary production. Model results show that of the 40 tera-grams of carbon produced annually in the Antarctic ice pack, 75 percent was associated with first-year ice and nearly 50 percent was produced in the Weddell Sea.

  3. Mysterious iodine-overabundance in Antarctic meteorites

    NASA Technical Reports Server (NTRS)

    Dreibus, G.; Waenke, H.; Schultz, L.

    1986-01-01

    Halogen as well as other trace element concentrations in meteorite finds can be influenced by alteration processes on the Earth's surface. The discovery of Antarctic meteorites offered the opportunity to study meteorites which were kept in one of the most sterile environment of the Earth. Halogen determination in Antartic meteorites was compared with non-Antarctic meteorites. No correlation was found between iodine concentration and the weathering index, or terrestrial age. The halogen measurements indicate a contaminating phase rich in iodine and also containing chlorine. Possible sources for this contamination are discussed.

  4. Fast wandering of slow birds

    NASA Astrophysics Data System (ADS)

    Toner, John

    2011-12-01

    I study a single slow bird moving with a flock of birds of a different and faster (or slower) species. I find that every species of flocker has a characteristic speed γ≠v0, where v0 is the mean speed of the flock such that if the speed vs of the slow bird equals γ, it will randomly wander transverse to the mean direction of flock motion far faster than the other birds will: Its mean-squared transverse displacement will grow in d=2 with time t like t5/3, in contrast to t4/3 for the other birds. In d=3, the slow bird's mean-squared transverse displacement grows like t5/4, in contrast to t for the other birds. If vs≠γ, the mean-squared displacement of the slow bird crosses over from t5/3 to t4/3 scaling in d=2 and from t5/4 to t scaling in d=3 at a time tc that scales according to tc∝|vs-γ|-2.

  5. Bird Cherry-Oat Aphid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bird cherry-oat aphid feeds on barley, oats, rye, triticale, and wheat by sucking plant juices. Its feeding may stunt plants and lead to yield loss, but it does not cause symptoms of yellowing and leaf curling. Bird cherry-oat aphid is also a vector of barley yellow dwarf virus. Biological, cultu...

  6. Laboratory Animal Management: Wild Birds.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Inst. of Lab. Animal Resources.

    This is a report on the care and use of wild birds in captivity as research animals. Chapters are presented on procurement and identification, housing, nutrition, health of birds and personnel, reproduction in confinement, and surgical procedures. Also included are addresses of federal, state, and provencial regulatory agencies concerned with wild…

  7. Long distance tracking of birds

    NASA Technical Reports Server (NTRS)

    Cochran, W. W.

    1972-01-01

    The application of radio telemetry techniques to the long distance tracking of birds is discussed. The types of equipment developed and methods for attachment to a bird are described. The operating range of the radio transmitter receiver system is examined, and methods for acquiring and analyzing the data are explained.

  8. Proceedings of a workshop on Differences Between Antarctic and Non-Antarctic Meteorites

    NASA Technical Reports Server (NTRS)

    Koeberl, Christian (Editor); Cassidy, William A. (Editor)

    1989-01-01

    The known facts, together with new research results are reviewed, in order to examine apparent differences between the Antarctic and non-Antarctic populations. In view of the statistically significant number of Antarctic meteorites, and the existence of rare or previously unknown types of meteorites among the Antarctic meteorite collection, the question was really not so much whether there are differences, but to define which ones are significant and what their origin is. Two main causes for the possible differences have been suggested previously, namely differences in the meteorite parent populations and secondary effects (e.g., weathering). The workshop was structured to contain sessions on chemical, isotopic, petrological, and mineralogical studies of meteorites from the two collections; terrestrial age determinations; discussions on mass frequency distributions; relative abundances of meteorite types; and terrestrial meteorite flux rates and their possible changes with time.

  9. Conservation of wading birds

    USGS Publications Warehouse

    Kushlan, J.A.

    1996-01-01

    The conservation and management of wading birds has received considerable attention over the past twenty years, through research, population monitoring, habitat protection, and through activities of specialist groups devoted to all three groups, the herons, ibises and allies, and flamingos. While populations are best known in North America, greatest advances in knowledge may have come in Australasia. The status of most species and many populations is now sufficiently known to allow assessment of risk. Conservation and management techniques allow creation of global and regional action plans for conservation of many species. Global action plans are being developed, but few regional plans have been undertaken. Management of nesting sites is now particularly well appreciated. Although known in broad stroke, much remains to be learned about managing feeding habitat. Problems related to disturbance, conflict with humans, habitat loss, contaminants and other environmental stresses remain for some species and many populations. New challenges lie in creating conservation action that account for genetic stocks.

  10. Antarctic Peninsula Tidewater Glacier Dynamics

    NASA Astrophysics Data System (ADS)

    Pettit, E. C.; Scambos, T. A.; Haran, T. M.; Wellner, J. S.; Domack, E. W.; Vernet, M.

    2015-12-01

    The northern Antarctic Peninsula (nAP, north of 66°S) is a north-south trending mountain range extending transverse across the prevailing westerly winds of the Southern Ocean resulting in an extreme west-to-east precipitation gradient. Snowfall on the west side of the AP is one to two orders of magnitude higher than the east side. This gradient drives short, steep, fast-flowing glaciers into narrow fjords on the west side, while longer lower-sloping glaciers flow down the east side into broader fjord valleys. This pattern in ice dynamics affects ice-ocean interaction on timescales of decades to centuries, and shapes the subglacial topography and submarine bathymetry on timescales of glacial cycles. In our study, we calculate ice flux for the western and eastern nAP using a drainage model that incorporates the modern ice surface topography, the RACMO-2 precipitation estimate, and recent estimates of ice thinning. Our results, coupled with observed rates of ice velocity from InSAR (I. Joughin, personal communication) and Landsat 8 -derived flow rates (this study), provide an estimate of ice thickness and fjord depth in grounded-ice areas for the largest outlet glaciers. East-side glaciers either still terminate in or have recently terminated in ice shelves. Sedimentary evidence from the inner fjords of the western glaciers indicates they had ice shelves during LIA time, and may still have transient floating ice tongues (tabular berg calvings are observed). Although direct oceanographic evidence is limited, the high accumulation rate and rapid ice flux implies cold basal ice for the western nAP glaciers and therefore weak subglacial discharge relative to eastern nAP glaciers and or other tidewater fjord systems such as in Alaska. Finally, despite lower accumulation rates on the east side, the large elongate drainage basins result in a greater ice flux funneled through fewer deeper glaciers. Due to the relation between ice flux and erosion, these east-side glaciers

  11. Antarctic Meteorite Newsletter, volume 6, number 2

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Meteorites from the 1981 and 1982 Antarctic collection are listed showing classification, weight, degree of weathering, degree of fractionation, % Fa, and % Fs. Physical and petrigraphic characteristics are described for 23 samples from the Allan Hills, Thiel Mountains, the Pecora Escarpment, and the Elephant Moraine locations.

  12. Relevance of antarctic microbial ecosystems to exobiology

    NASA Technical Reports Server (NTRS)

    Mckay, Christopher P.

    1993-01-01

    Antarctic microbial ecosystems which provide biological and physical analogs that can be used in exobiology are studied. Since the access to extraterrestrial habitats is extremely difficult, terrestrial analogs represent the best opportunity for both formulation and preliminary testing of hypothesis about life. Antarctica, as one of few suitable environments on earth is considered to be a major locus of progress in exobiology.

  13. Development of the circum-antarctic current.

    PubMed

    Kennett, J P; Houtz, R E; Andrews, P B; Edwards, A R; Gostin, V A; Hajos, M; Hampton, M A; Jenkins, D G; Margolis, S V; Ovenshine, A T; Perch-Nielsen, K

    1974-10-11

    Deep-sea drilling in the Southern Ocean south of Australia and New Zealand shows that the Circum-Antarctic Current developed about 30 million years ago in the middle to late Oligocene when final separation occurred between Antarctica and the continental South Tasman Rise. Australia had commenced drifting northward from Antarctica 20 million years before this. PMID:17744222

  14. NASA/NSF Antarctic Science Working Group

    NASA Technical Reports Server (NTRS)

    Stoklosa, Janis H.

    1990-01-01

    A collection of viewgraphs on NASA's Life Sciences Biomedical Programs is presented. They show the structure of the Life Sciences Division; the tentative space exploration schedule from the present to 2018; the biomedical programs with their objectives, research elements, and methodological approaches; validation models; proposed Antarctic research as an analog for space exploration; and the Science Working Group's schedule of events.

  15. Antarctic springtime depletion of atmospheric mercury.

    PubMed

    Ebinghaus, Ralf; Kock, Hans H; Temme, Christian; Einax, Jürgen W; Lowe, Astrid G; Richter, Andreas; Burrows, John P; Schroeder, William H

    2002-03-15

    Unlike other heavy metals that are inherently associated with atmospheric aerosols, mercury in ambient air exists predominantly in the gaseous elemental form. Because of its prolonged atmospheric residence time, elemental mercury vapor is distributed on a global scale. Recently, Canadian researchers have discovered that total gaseous mercury levels in the lower tropospheric boundary layer in the Canadian Arctic are often significantly depleted during the months after polar sunrise. A possible explanation may involve oxidation of elemental mercury, followed by adsorption and deposition of the oxidized form, leading to an increased input of atmospheric mercury into the Arctic ecosystem. Here we present the first continuous high-time-resolution measurements of total gaseous mercury in the Antarctic covering a 12-month period between January 2000 and January 2001 at the German Antarctic research station Neumayer (70 degrees 39' S, 8 degrees 15' W). We report that mercury depletion events also occur in the Antarctic after polar sunrise and compare our measurements with a data setfrom Alert, Nunavut, Canada. We also present indications that BrO radicals and ozone play a key role in the boundary-layer chemistry during springtime mercury depletion events in the Antarctic troposphere. PMID:11944675

  16. Antarctic Tephra Database (AntT)

    NASA Astrophysics Data System (ADS)

    Kurbatov, A.; Dunbar, N. W.; Iverson, N. A.; Gerbi, C. C.; Yates, M. G.; Kalteyer, D.; McIntosh, W. C.

    2014-12-01

    Modern paleoclimate research is heavily dependent on establishing accurate timing related to rapid shifts in Earth's climate system. The ability to correlate these events at local, and ideally at the intercontinental scales, allows assessment, for example, of phasing or changes in atmospheric circulation. Tephra-producing volcanic eruptions are geologically instantaneous events that are largely independent of climate. We have developed a tephrochronological framework for paleoclimate research in Antarctic in a user friendly, freely accessible online Antarctic tephra (AntT) database (http://cci.um.maine.edu/AntT/). Information about volcanic events, including physical and geochemical characteristics of volcanic products collected from multiple data sources, are integrated into the AntT database.The AntT project establishes a new centralized data repository for Antarctic tephrochronology, which is needed for precise correlation of records between Antarctic ice cores (e.g. WAIS Divide, RICE, Talos Dome, ITASE) and global paleoclimate archives. The AntT will help climatologists, paleoclimatologists, atmospheric chemists, geochemists, climate modelers synchronize paleoclimate archives using volcanic products that establishing timing of climate events in different geographic areas, climate-forcing mechanisms, natural threshold levels in the climate system. All these disciplines will benefit from accurate reconstructions of the temporal and spatial distribution of past rapid climate change events in continental, atmospheric, marine and polar realms. Research is funded by NSF grants: ANT-1142007 and 1142069.

  17. Anatomy of a Bird

    NASA Astrophysics Data System (ADS)

    2007-12-01

    Using ESO's Very Large Telescope, an international team of astronomers [1] has discovered a stunning rare case of a triple merger of galaxies. This system, which astronomers have dubbed 'The Bird' - albeit it also bears resemblance with a cosmic Tinker Bell - is composed of two massive spiral galaxies and a third irregular galaxy. ESO PR Photo 55a/07 ESO PR Photo 55a/07 The Tinker Bell Triplet The galaxy ESO 593-IG 008, or IRAS 19115-2124, was previously merely known as an interacting pair of galaxies at a distance of 650 million light-years. But surprises were revealed by observations made with the NACO instrument attached to ESO's VLT, which peered through the all-pervasive dust clouds, using adaptive optics to resolve the finest details [2]. Underneath the chaotic appearance of the optical Hubble images - retrieved from the Hubble Space Telescope archive - the NACO images show two unmistakable galaxies, one a barred spiral while the other is more irregular. The surprise lay in the clear identification of a third, clearly separate component, an irregular, yet fairly massive galaxy that seems to be forming stars at a frantic rate. "Examples of mergers of three galaxies of roughly similar sizes are rare," says Petri Väisänen, lead author of the paper reporting the results. "Only the near-infrared VLT observations made it possible to identify the triple merger nature of the system in this case." Because of the resemblance of the system to a bird, the object was dubbed as such, with the 'head' being the third component, and the 'heart' and 'body' making the two major galaxy nuclei in-between of tidal tails, the 'wings'. The latter extend more than 100,000 light-years, or the size of our own Milky Way. ESO PR Photo 55b/07 ESO PR Photo 55b/07 Anatomy of a Bird Subsequent optical spectroscopy with the new Southern African Large Telescope, and archive mid-infrared data from the NASA Spitzer space observatory, confirmed the separate nature of the 'head', but also added

  18. Is your bird feeder safe?

    USGS Publications Warehouse

    Ruth, J.; Friend, M.

    1997-01-01

    Bird feeding is a popular activity for millions of Americans. Some of our favorite bird species commonly visit bird feeders and these stations may be an important factor in their well-being during some segments of their life-cycle. However, poorly maintained feeding stations may contribute to the occurrence of infectious disease and mortality. In recent years there have been unprecedented reports of songbird mortality events and the occurrence of a previously unreported disease in songbirds. The National Wildlife Health Center of the U.S. Geological Survey conducts research on diseases in wildlife, their causes, and means of preventing or reducing disease outbreaks.

  19. Neogene kinematic history of Nazca-Antarctic-Phoenix slab windows beneath Patagonia and the Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Breitsprecher, Katrin; Thorkelson, Derek J.

    2009-01-01

    The Patagonian slab window is a subsurface tectonic feature resulting from subduction of the Nazca-Antarctic spreading-ridge system (Chile Rise) beneath southern South America. The geometry of the slab window had not been rigorously defined, in part because of the complex nature of the history of ridge subduction in the southeast Pacific region, which includes four interrelated spreading-ridge systems since 20 Ma: first, the Nazca-Phoenix ridge beneath South America, then simultaneous subduction of the Nazca-Antarctic and the northern Phoenix-Antarctic spreading-ridge systems beneath South America, and the southern Phoenix-Antarctic spreading-ridge system beneath Antarctica. Spreading-ridge paleo-geographies and rotation poles for all relevant plate pairs (Nazca, Phoenix, Antarctic, South America) are available from 20 Ma onward, and form the mathematical basis of our kinematic reconstruction of the geometry of the Patagonia and Antarctic slab windows through Neogene time. At approximately 18 Ma, the Nazca-Phoenix-Antarctic oceanic (ridge-ridge-ridge) triple junction enters the South American trench; we recognize this condition as an unstable quadruple junction. Heat flow at this junction and for some distance beneath the forearc would be considerably higher than is generally recognized in cases of ridge subduction. From 16 Ma onward, the geometry of the Patagonia slab window developed from the subduction of the trailing arms of the former oceanic triple junction. The majority of the slab window's areal extent and geometry is controlled by the highly oblique (near-parallel) subduction angle of the Nazca-Antarctic ridge system, and by the high contrast in relative convergence rates between these two plates relative to South America. The very slow convergence rate of the Antarctic slab is manifested by the shallow levels achieved by the slab edge (< 45 km); thus no point on the Antarctic slab is sufficiently deep to generate "normal" mantle-derived arc-type magmas

  20. BirdVis: visualizing and understanding bird populations.

    PubMed

    Ferreira, Nivan; Lins, Lauro; Fink, Daniel; Kelling, Steve; Wood, Chris; Freire, Juliana; Silva, Cláudio

    2011-12-01

    Birds are unrivaled windows into biotic processes at all levels and are proven indicators of ecological well-being. Understanding the determinants of species distributions and their dynamics is an important aspect of ecology and is critical for conservation and management. Through crowdsourcing, since 2002, the eBird project has been collecting bird observation records. These observations, together with local-scale environmental covariates such as climate, habitat, and vegetation phenology have been a valuable resource for a global community of educators, land managers, ornithologists, and conservation biologists. By associating environmental inputs with observed patterns of bird occurrence, predictive models have been developed that provide a statistical framework to harness available data for predicting species distributions and making inferences about species-habitat associations. Understanding these models, however, is challenging because they require scientists to quantify and compare multiscale spatialtemporal patterns. A large series of coordinated or sequential plots must be generated, individually programmed, and manually composed for analysis. This hampers the exploration and is a barrier to making the cross-species comparisons that are essential for coordinating conservation and extracting important ecological information. To address these limitations, as part of a collaboration among computer scientists, statisticians, biologists and ornithologists, we have developed BirdVis, an interactive visualization system that supports the analysis of spatio-temporal bird distribution models. BirdVis leverages visualization techniques and uses them in a novel way to better assist users in the exploration of interdependencies among model parameters. Furthermore, the system allows for comparative visualization through coordinated views, providing an intuitive interface to identify relevant correlations and patterns. We justify our design decisions and present case

  1. Migrating Birds and Tickborne Encephalitis Virus

    PubMed Central

    Lundkvist, Åke; Falk, Kerstin I.; Garpmo, Ulf; Bergström, Sven; Lindegren, Gunnel; Sjöstedt, Anders; Mejlon, Hans; Fransson, Thord; Haemig, Paul D.; Olsen, Björn

    2007-01-01

    During spring and autumn 2001, we screened 13,260 migrating birds at Ottenby Bird Observatory, Sweden, and found 3.4% were infested with ticks. Four birds, each a different passerine species, carried tickborne encephalitis virus (TBEV)–infected ticks (Ixodes ricinus). Migrating birds may play a role in the geographic dispersal of TBEV-infected ticks. PMID:17953095

  2. 21 CFR 1240.65 - Psittacine birds.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Psittacine birds. 1240.65 Section 1240.65 Food and... DISEASES Specific Administrative Decisions Regarding Interstate Shipments § 1240.65 Psittacine birds. (a) The term psittacine birds shall include all birds commonly known as parrots, Amazons, Mexican...

  3. 21 CFR 1240.65 - Psittacine birds.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Psittacine birds. 1240.65 Section 1240.65 Food and... DISEASES Specific Administrative Decisions Regarding Interstate Shipments § 1240.65 Psittacine birds. (a) The term psittacine birds shall include all birds commonly known as parrots, Amazons, Mexican...

  4. The Antarctic Master Directory -- the Electronic Card Catalog of Antarctic Data

    NASA Astrophysics Data System (ADS)

    Scharfen, G.; Bauer, R.

    2003-12-01

    The Antarctic Master Directory (AMD) is a Web-based, searchable record of thousands of Antarctic data descriptions. These data descriptions contain information about what data were collected, where they were collected, when they were collected, who the scientists are, who the point of contact is, how to get the data, and information about the format of the data and what documentation and bibliographic information exists. With this basic descriptive information about content and access for thousands of Antarctic scientific data sets, the AMD is a resource for scientists to advertise the data they have collected and to search for data they need. The AMD has been created by more than twenty nations which conduct research in the Antarctic under the auspices of the Antarctic Treaty. It is a part of the International Directory Network/Global Change Master Directory (IDN/GCMD). Using the AMD is easy. Users can search on subject matter key words, data types, geographic place-names, temporal or spatial ranges, or conduct free-text searches. To search the AMD go to: http://gcmd.nasa.gov/Data/portals/amd/. Contributing your own data descriptions for Antarctic data that you have collected is also easy. Scientists can start by submitting a short data description first (as a placeholder in the AMD, and to satisfy National Science Foundation (NSF) reporting requirements), and then add to, modify or update their record whenever it is appropriate. An easy to use on-line tool and a simple tutorial are available at: http://nsidc.org/usadcc. With NSF Office of Polar Programs (OPP) funding, the National Snow and Ice Data Center (NSIDC) operates the U.S. Antarctic Data Coordination Center (USADCC), partly to assist scientists in using and contributing to the AMD. The USADCC website is at http://nsidc.org/usadcc.

  5. The Variety of Shore Birds

    ERIC Educational Resources Information Center

    Varza, Dennis

    1977-01-01

    The types of habitats that exist along the ocean shore and the various types of birds inhabiting them are detailed. Topics discussed include shorebird feeding habits and methods, nesting patterns, and seasonal migration. (BT)

  6. Poisonous birds: A timely review.

    PubMed

    Ligabue-Braun, Rodrigo; Carlini, Célia Regina

    2015-06-01

    Until very recently, toxicity was not considered a trait observed in birds, but works published in the last two decades started to shed light on this subject. Poisonous birds are rare (or little studied), and comprise Pitohui and Ifrita birds from Papua New Guinea, the European quail, the Spoor-winged goose, the Hoopees, the North American Ruffed grouse, the Bronzewings, and the Red warbler. A hundred more species are considered unpalatable or malodorous to humans and other animals. The present review intends to present the current understanding of bird toxicity, possibly pointing to an ignored research field. Whenever possible, biochemical characteristics of these poisons and their effects on humans and other animals are discussed, along with historical aspects of poison discovery and evolutionary hypothesis regarding their function. PMID:25839151

  7. Migratory birds, ticks, and Bartonella

    PubMed Central

    Molin, Ylva; Lindeborg, Mats; Nyström, Fredrik; Madder, Maxime; Hjelm, Eva; Olsen, Björn; Jaenson, Thomas G.T.; Ehrenborg, Christian

    2011-01-01

    Bartonella spp. infections are considered to be vector-borne zoonoses; ticks are suspected vectors of bartonellae. Migratory birds can disperse ticks infected with zoonotic pathogens such as Rickettsia and tick-borne encephalitis virus and possibly also Bartonella. Thus, in the present study 386 tick specimens collected in spring 2009 from migratory birds on the Mediterranean islands Capri and Antikythera were screened for Bartonella spp. RNA. One or more ticks were found on 2.7% of the birds. Most ticks were Hyalomma rufipes nymphs and larvae with mean infestation rates of 1.7 nymphs and 0.6 larvae per infested bird. Bartonella spp. RNA was not detected in any of the tick specimens. PMID:22957116

  8. Unzipping bird feathers

    PubMed Central

    Kovalev, Alexander; Filippov, Alexander E.; Gorb, Stanislav N.

    2014-01-01

    The bird feather vane can be separated into two parts by pulling the barbs apart. The original state can be re-established easily by lightly stroking through the feather. Hooklets responsible for holding vane barbs together are not damaged by multiple zipping and unzipping cycles. Because numerous microhooks keep the integrity of the feather, their properties are of great interest for understanding mechanics of the entire feather structure. This study was undertaken to estimate the separation force of single hooklets and their arrays using force measurement of an unzipping feather vane. The hooklets usually separate in some number synchronously (20 on average) with the highest observed separation force of 1.74 mN (average force 0.27 mN), whereas the single hooklet separation force was 14 μN. A simple numerical model was suggested for a better understanding of zipping and unzipping behaviour in feathers. The model demonstrates features similar to those observed in experiments. PMID:24352674

  9. Structural Colors of Birds

    NASA Astrophysics Data System (ADS)

    Hall, Cecilia; Dushkina, Natalia

    2016-03-01

    Structural colors create iridescent colors in bird feathers. The goal is to understand why structural colors act the way they do in certain situations. The research conducted over the course of the fall semester was to understand the optical phenomenon producing colors in individual barbules. Through the use of a polarizing optical microscope, certain hypotheses were built to explain certain phenomenon. Using a dark field illumination involving light acting at wide angles in microscopy, the barbules were not affected by polarization. So it can be suggested that the barbules have certain characteristics, possibly internal, which prevents wide-angle polarization. More recently, it was found that the barbules, when stacked upon one another, create a discoloration at the cross over point. It can be suggested that the barbules act as thin films and create a situation of thin film interference. More data will be taken using the Scanning Electron Microscope as well as getting cross sectional data to help understand the internal characteristics of the barbules. From the support of the Neimeyer-Hodgson Grant, Chris Stull, and Millersville University of Pennsylvania.

  10. Unzipping bird feathers.

    PubMed

    Kovalev, Alexander; Filippov, Alexander E; Gorb, Stanislav N

    2014-03-01

    The bird feather vane can be separated into two parts by pulling the barbs apart. The original state can be re-established easily by lightly stroking through the feather. Hooklets responsible for holding vane barbs together are not damaged by multiple zipping and unzipping cycles. Because numerous microhooks keep the integrity of the feather, their properties are of great interest for understanding mechanics of the entire feather structure. This study was undertaken to estimate the separation force of single hooklets and their arrays using force measurement of an unzipping feather vane. The hooklets usually separate in some number synchronously (20 on average) with the highest observed separation force of 1.74 mN (average force 0.27 mN), whereas the single hooklet separation force was 14 μN. A simple numerical model was suggested for a better understanding of zipping and unzipping behaviour in feathers. The model demonstrates features similar to those observed in experiments. PMID:24352674

  11. Birds and bornaviruses.

    PubMed

    Payne, Susan L; Delnatte, Pauline; Guo, Jianhua; Heatley, J Jill; Tizard, Ian; Smith, Dale A

    2012-12-01

    In 2008, avian bornaviruses (ABV) were identified as the cause of proventricular dilatation disease (PDD). PDD is a significant condition of captive parrots first identified in the late 1970s. ABV infection has subsequently been shown to be widespread in wild waterfowl across the United States and Canada where the virus infects 10-20% of some populations of ducks, geese and swans. In most cases birds appear to be healthy and unaffected by the presence of the virus; however, infection can also result in severe non-suppurative encephalitis and lesions similar to those seen in parrots with PDD. ABVs are genetically diverse with seven identified genotypes in parrots and one in canaries. A unique goose genotype (ABV-CG) predominates in waterfowl in Canada and the northern United States. ABV appears to be endemic in North American waterfowl, in comparison to what appears to be an emerging disease in parrots. It is not known whether ABV can spread between waterfowl and parrots. The discovery of ABV infection in North American waterfowl suggests that European waterfowl should be evaluated for the presence of ABV, and also as a possible reservoir species for Borna disease virus (BDV), a related neurotropic virus affecting horses and sheep in central Europe. Although investigations have suggested that BDV is likely derived from a wildlife reservoir, for which the shrew and water vole are currently prime candidates, we suggest that the existence of other mammalian and avian reservoirs should not be discounted. PMID:23253163

  12. Observing Flat Birds and Other Fun Birding Activities for K-12 Students.

    ERIC Educational Resources Information Center

    Matthews, Catherine E.; Connors, John

    2002-01-01

    Introduces the concept of the flat bird, which is a life-size color cutout of a bird, and uses flat birds to introduce the study of birds. Includes suggestions for teaching about common characteristics of birds and information on resource materials. (YDS)

  13. Emerging spatial patterns in Antarctic prokaryotes.

    PubMed

    Chong, Chun-Wie; Pearce, David A; Convey, Peter

    2015-01-01

    Recent advances in knowledge of patterns of biogeography in terrestrial eukaryotic organisms have led to a fundamental paradigm shift in understanding of the controls and history of life on land in Antarctica, and its interactions over the long term with the glaciological and geological processes that have shaped the continent. However, while it has long been recognized that the terrestrial ecosystems of Antarctica are dominated by microbes and their processes, knowledge of microbial diversity and distributions has lagged far behind that of the macroscopic eukaryote organisms. Increasing human contact with and activity in the continent is leading to risks of biological contamination and change in a region whose isolation has protected it for millions of years at least; these risks may be particularly acute for microbial communities which have, as yet, received scant recognition and attention. Even a matter apparently as straightforward as Protected Area designation in Antarctica requires robust biodiversity data which, in most parts of the continent, remain almost completely unavailable. A range of important contributing factors mean that it is now timely to reconsider the state of knowledge of Antarctic terrestrial prokaryotes. Rapid advances in molecular biological approaches are increasingly demonstrating that bacterial diversity in Antarctica may be far greater than previously thought, and that there is overlap in the environmental controls affecting both Antarctic prokaryotic and eukaryotic communities. Bacterial dispersal mechanisms and colonization patterns remain largely unaddressed, although evidence for regional evolutionary differentiation is rapidly accruing and, with this, there is increasing appreciation of patterns in regional bacterial biogeography in this large part of the globe. In this review, we set out to describe the state of knowledge of Antarctic prokaryote diversity patterns, drawing analogy with those of eukaryote groups where appropriate

  14. Emerging spatial patterns in Antarctic prokaryotes

    PubMed Central

    Chong, Chun-Wie; Pearce, David A.; Convey, Peter

    2015-01-01

    Recent advances in knowledge of patterns of biogeography in terrestrial eukaryotic organisms have led to a fundamental paradigm shift in understanding of the controls and history of life on land in Antarctica, and its interactions over the long term with the glaciological and geological processes that have shaped the continent. However, while it has long been recognized that the terrestrial ecosystems of Antarctica are dominated by microbes and their processes, knowledge of microbial diversity and distributions has lagged far behind that of the macroscopic eukaryote organisms. Increasing human contact with and activity in the continent is leading to risks of biological contamination and change in a region whose isolation has protected it for millions of years at least; these risks may be particularly acute for microbial communities which have, as yet, received scant recognition and attention. Even a matter apparently as straightforward as Protected Area designation in Antarctica requires robust biodiversity data which, in most parts of the continent, remain almost completely unavailable. A range of important contributing factors mean that it is now timely to reconsider the state of knowledge of Antarctic terrestrial prokaryotes. Rapid advances in molecular biological approaches are increasingly demonstrating that bacterial diversity in Antarctica may be far greater than previously thought, and that there is overlap in the environmental controls affecting both Antarctic prokaryotic and eukaryotic communities. Bacterial dispersal mechanisms and colonization patterns remain largely unaddressed, although evidence for regional evolutionary differentiation is rapidly accruing and, with this, there is increasing appreciation of patterns in regional bacterial biogeography in this large part of the globe. In this review, we set out to describe the state of knowledge of Antarctic prokaryote diversity patterns, drawing analogy with those of eukaryote groups where appropriate

  15. 77 FR 7610 - Notice of permit applications received under the Antarctic Conservation Act of 1978

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-13

    ... Notice of permit applications received under the Antarctic Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received Under the Antarctic Conservation Act of... of permit applications received to conduct activities regulated under the Antarctic Conservation...

  16. Chemical studies of H chondrites. 6: Antarctic/non-Antarctic compositional differences revisited

    NASA Technical Reports Server (NTRS)

    Wolf, Stephen F.; Lipschutz, Michael E.

    1995-01-01

    We report data for the trace elements Au, Co, Sb, Ga, Rb, Ag, Se, Cs, Te, Zn, Cd, Bi, T1, and In (ordered by putative volatility during nebular condensation and accretion) determined by radiochemical neutron activation analysis of 14 additional H5 and H6 chondrite falls. Data for the 10 most volatile elements (Rb to In) treated by the multivariate techniques of linear discriminant analysis and logistic regression in these and 44 other falls are compared with those of 59 H4-6 chondrites from Antarctica. Various populations are tested by the multivariate techniques, using the previously developed method of randomization-simulation to assess significance levels. An earlier conclusion, based on fewer examples, that H4-6 chondrite falls are compositionally distinguishable from the Antarctic suite is verified by the additional data. This distinctiveness is highly significant because of the presence of samples from Victoria Land in the Antarctic population, which differ compositionally from falls beyond any reasonable doubt. However, it cannot be proven unequivocally that falls and Antarctic samples from Queen Maud Land are compositionally distinguishable. Trivial causes (e.g., analyst bias, weathering) cannot explain the Victoria Land (Antarctic)/non-Antarctic compositional difference for paradigmatic H4-6 chondrites. This seems to reflect a time-dependent variation of near-Earth meteoroid source regions differing in average thermal history.

  17. The magnetic orientation of the Antarctic amphipod Gondogeneia antarctica is cancelled by very weak radiofrequency fields.

    PubMed

    Tomanova, K; Vacha, M

    2016-06-01

    Studies on weak man-made radiofrequency (RF) electromagnetic fields affecting animal magnetoreception aim for a better understanding of the reception mechanism and also point to a new phenomenon having possible consequences in ecology and environmental protection. RF impacts on magnetic compasses have recently been demonstrated in migratory birds and other vertebrates. We set out to investigate the effect of RF on the magnetic orientation of the Antarctic krill species Gondogeneia antarctica, a small marine crustacean widespread along the Antarctic littoral line. Here, we show that upon release, G. antarctica (held under laboratory conditions) escaped in the magnetically seaward direction along the magnetic sea-land axis (y-axis) of the home beach. However, the animals were disoriented after being exposed to RF. Orientation was lost not only in an RF field with a magnetic flux density of 20 nT, as expected according to the literature, but even under the 2 nT originally intended as a control. Our results extend recent findings of the extraordinary sensitivity of animal magnetoreception to weak RF fields in marine invertebrates. PMID:27026715

  18. Benchmarking of data fusion algorithms in support of earth observation based Antarctic wildlife monitoring

    NASA Astrophysics Data System (ADS)

    Witharana, Chandi; LaRue, Michelle A.; Lynch, Heather J.

    2016-03-01

    Remote sensing is a rapidly developing tool for mapping the abundance and distribution of Antarctic wildlife. While both panchromatic and multispectral imagery have been used in this context, image fusion techniques have received little attention. We tasked seven widely-used fusion algorithms: Ehlers fusion, hyperspherical color space fusion, high-pass fusion, principal component analysis (PCA) fusion, University of New Brunswick fusion, and wavelet-PCA fusion to resolution enhance a series of single-date QuickBird-2 and Worldview-2 image scenes comprising penguin guano, seals, and vegetation. Fused images were assessed for spectral and spatial fidelity using a variety of quantitative quality indicators and visual inspection methods. Our visual evaluation elected the high-pass fusion algorithm and the University of New Brunswick fusion algorithm as best for manual wildlife detection while the quantitative assessment suggested the Gram-Schmidt fusion algorithm and the University of New Brunswick fusion algorithm as best for automated classification. The hyperspherical color space fusion algorithm exhibited mediocre results in terms of spectral and spatial fidelities. The PCA fusion algorithm showed spatial superiority at the expense of spectral inconsistencies. The Ehlers fusion algorithm and the wavelet-PCA algorithm showed the weakest performances. As remote sensing becomes a more routine method of surveying Antarctic wildlife, these benchmarks will provide guidance for image fusion and pave the way for more standardized products for specific types of wildlife surveys.

  19. Birds of a feather

    USGS Publications Warehouse

    Knick, Steven T.; Gondhaleker, Carmen

    2014-01-01

    Greater sage-grouse (Centrocercus urophasiunus, hereafter sage-grouse) are broadly distributed, occupy a diversity of sagebrush habitats, and face multiple threats. As a result of these threats, sage-grouse populations are declining and are now absent from almost one-half of their estimated range prior to Euro-American settlement. The risks to sage-grouse are significant enough to merit candidate status for this species for listing under the U.S. Endangered Species Act (Federal Register Notice, March 5, 2010). According to this decision by the U.S. Fish and Wildlife Service in 2010, population and habitat fragmentation coupled with lack of regulatory mechanisms warranted listing, although implementation of actions has been precluded by other priorities. Candidate status for listing under the Endangered Species Act and possible regulatory action in the near future provide strong motivation to better understand the dynamics of sage-grouse populations and their habitat requirements. The general approach currently taken by managers focuses on maintaining or enhancing sage-grouse populations across their distribution in regions containing the highest densities of breeding birds and their important seasonal habitats, also known as priority areas for conservation (PACs). The rationale behind this approach is that it permits limited resources to be applied in regions that have the greatest potential to benefit the largest proportion of sage-grouse. Development and other forms of land use can then proceed under standard regulations in areas outside PACs. Implementation of this approach requires detailed information about habitat, connections among sage-grouse populations, and approaches to restore and maintain sagebrush. These are important topics of study by the U.S. Geological Survey (USGS) and its research partners.

  20. Subsurface Salts in Antarctic Dry Valley Soils

    NASA Technical Reports Server (NTRS)

    Englert, P.; Bishop, J. L.; Gibson, E. K.; Koeberl, C.

    2013-01-01

    The distribution of water-soluble ions, major and minor elements, and other parameters were examined to determine the extent and effects of chemical weathering on cold desert soils. Patterns at the study sites support theories of multiple salt forming processes, including marine aerosols and chemical weathering of mafic minerals. Periodic solar-mediated ionization of atmospheric nitrogen might also produce high nitrate concentrations found in older sediments. Chemical weathering, however, was the major contributor of salts in Antarctic Dry Valleys. The Antarctic Dry Valleys represent a unique analog for Mars, as they are extremely cold and dry desert environments. Similarities in the climate, surface geology, and chemical properties of the Dry Valleys to that of Mars imply the possible presence of these soil formation mechanisms on Mars, other planets and icy satellites.

  1. Meteoritic event recorded in Antarctic ice

    SciTech Connect

    Harvey, R.P.; Dunbar, N.W.; McIntosh, W.C.; Esser, R.P.; Nishiizumi, Kuni; Taylor, S.; Caffee, M.W.

    1998-07-01

    During systematic sampling of volcanic ash (tephra) layers at a well-known Antarctic meteorite collection site (the Allan Hills main ice field), a band of unusually dark and rounded (many spheroidal) particles was discovered. This debris layer (BIT-58) extends parallel to the stratigraphy of the ice established from the tephra bands, apparently marking a single depositional event. The shapes, internal texture, major element composition, and levels of cosmogenic nuclides of particles from within BIT-58 all strongly suggest that this material represents ablation debris from the passage of a large H-group ordinary chondrite. Preliminary cosmogenic isotope dating suggests an age of 2.8 Ma, implying that the East Antarctic ice sheet has been stable since that time. The relationship of the Bit-58 layer to known impact events is not clear.

  2. Molecular adaptations in Antarctic fish and bacteria

    NASA Astrophysics Data System (ADS)

    Russo, Roberta; Riccio, Alessia; di Prisco, Guido; Verde, Cinzia; Giordano, Daniela

    2010-08-01

    Marine organisms, living in the cold waters of the Southern Ocean, are exposed to high oxygen concentrations. Cold-adapted organisms have developed networks of defence mechanisms to protect themselves against oxidative stress. The dominant suborder Notothenioidei of the Southern Ocean is one of the most interesting models, within vertebrates, to study the evolutionary biological responses to extreme environment. Within bacteria, the psychrophilic Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 gives the opportunity to explore the cellular strategies adopted in vivo by cold-adapted microorganisms to cope with cold and high oxygen concentration. Understanding the molecular mechanisms underlying how a range of Antarctic organisms have responded to climate change in the past will enable predictions as to how they and other species will adapt to global climate change, in terms of physiological function, distribution patterns and ecosystem balance.

  3. Antarctic ice rise formation, evolution, and stability

    NASA Astrophysics Data System (ADS)

    Favier, Lionel; Pattyn, Frank

    2015-06-01

    Antarctic ice rises originate from the contact between ice shelves and one of the numerous topographic highs emerging from the edge of the continental shelf. While investigations of the Raymond effect indicate their millennial-scale stability, little is known about their formation and their role in ice shelf stability. Here we present for the first time the simulation of an ice rise using the BISICLES model. The numerical results successfully reproduce several field-observable features, such as the substantial thinning downstream of the ice rise and the successive formation of a promontory and ice rise with stable radial ice flow center, showing that ice rises are formed during the ice sheet deglaciation. We quantify the ice rise buttressing effect, found to be mostly transient, delaying grounding line retreat significantly but resulting in comparable steady state positions. We demonstrate that ice rises are key in controlling simulations of Antarctic deglaciation.

  4. A simulated Antarctic fast ice ecosystem

    NASA Technical Reports Server (NTRS)

    Arrigo, Kevin R.; Kremer, James N.; Sullivan, Cornelius W.

    1993-01-01

    A 2D numerical ecosystem model of Antarctic land fast ice is developed to elucidate the primary production with the Antarctic sea ice zone. The physical component employs atmospheric data to simulate congelation ice growth, initial brine entrapment, desalination, and nutrient flux. The biological component is based on the concept of a maximum temperature-dependent algal growth rate which is reduced by limitations imposed from insufficient light or nutrients, as well as suboptimal salinity. Preliminary simulations indicate that, during a bloom, microalgae are able to maintain their vertical position relative to the lower congelation ice margin and are not incorporated into the crystal matrix as the ice sheet thickens. It is inferred that land fast sea ice contains numerous microhabitats that are functionally distinct based upon the unique set of processes that control microalgal growth and accumulation within each.

  5. [Taxonomical status of the psychrotolerant Antarctic microorganisms].

    PubMed

    Romanovskaia, V A; Gladka, G V; Tashireva, A A; Tashirev, A B

    2013-01-01

    The aerobic chemoorganotrophic bacteria, dominating in soils and phytocenosis of the Antarctic Region, on combination of morphological and biochemical properties belong to several taxons of Bacteria domain. Gram-negative strains 3189, 3415 (fam. Halomonadaceae, Halomonas sp.) and 3088, 3468, 3469 (fam. Moraxellaceae, Psychrobacter sp.) belong to phylum Proteobacteria, to class Gammaproteobacteria. Gram-negative strains 3294 3392 (Rhizobiales, fam. Methylobacteriaceae, Methylobacterium sp.) relate to class Alphaproteobacteria of this phylum. Gram-positive strains 3179, 3275, 3470, 3471 (fam. Microbacteriaceae, Cryobacterium sp.), 3054, 3058, 3411 (fam. Corynebacteriaceae, Corynebacterium sp.) and 3194, 3398 (fam. Micrococcaceae, Micrococcus sp.) relate to phylum Actinobacteria, class Actinobacteria. Thus, the psychrophilic and psychrotolerant Antarctic bacteria (aerobic chemoorganotrophic) isolated from phytocenosis and soils of polar region are characterized by wide taxonomic variety. PMID:24450178

  6. Antarctic Meteorite Classification and Petrographic Database

    NASA Technical Reports Server (NTRS)

    Todd, Nancy S.; Satterwhite, C. E.; Righter, Kevin

    2011-01-01

    The Antarctic Meteorite collection, which is comprised of over 18,700 meteorites, is one of the largest collections of meteorites in the world. These meteorites have been collected since the late 1970's as part of a three-agency agreement between NASA, the National Science Foundation, and the Smithsonian Institution [1]. Samples collected each season are analyzed at NASA s Meteorite Lab and the Smithsonian Institution and results are published twice a year in the Antarctic Meteorite Newsletter, which has been in publication since 1978. Each newsletter lists the samples collected and processed and provides more in-depth details on selected samples of importance to the scientific community. Data about these meteorites is also published on the NASA Curation website [2] and made available through the Meteorite Classification Database allowing scientists to search by a variety of parameters

  7. Lab-on-a-Bird: Biophysical Monitoring of Flying Birds

    PubMed Central

    Gumus, Abdurrahman; Lee, Seoho; Ahsan, Syed S.; Karlsson, Kolbeinn; Gabrielson, Richard; Guglielmo, Christopher G.; Winkler, David W.; Erickson, David

    2015-01-01

    The metabolism of birds is finely tuned to their activities and environments, and thus research on avian systems can play an important role in understanding organismal responses to environmental changes. At present, however, the physiological monitoring of bird metabolism is limited by the inability to take real-time measurements of key metabolites during flight. In this study, we present an implantable biosensor system that can be used for continuous monitoring of uric acid levels of birds during various activities including flight. The system consists of a needle-type enzymatic biosensor for the amperometric detection of uric acid in interstitial fluids. A lightweight two-electrode potentiostat system drives the biosensor, reads the corresponding output current and wirelessly transfers the data or records to flash memory. We show how the device can be used to monitor, in real time, the effects of short-term flight and rest cycles on the uric acid levels of pigeons. In addition, we demonstrate that our device has the ability to measure uric acid level increase in homing pigeons while they fly freely. Successful application of the sensor in migratory birds could open up a new way of studying birds in flight which would lead to a better understanding of the ecology and biology of avian movements. PMID:25880904

  8. Do birds sleep in flight?

    NASA Astrophysics Data System (ADS)

    Rattenborg, Niels C.

    2006-09-01

    The following review examines the evidence for sleep in flying birds. The daily need to sleep in most animals has led to the common belief that birds, such as the common swift ( Apus apus), which spend the night on the wing, sleep in flight. The electroencephalogram (EEG) recordings required to detect sleep in flight have not been performed, however, rendering the evidence for sleep in flight circumstantial. The neurophysiology of sleep and flight suggests that some types of sleep might be compatible with flight. As in mammals, birds exhibit two types of sleep, slow-wave sleep (SWS) and rapid eye-movement (REM) sleep. Whereas, SWS can occur in one or both brain hemispheres at a time, REM sleep only occurs bihemispherically. During unihemispheric SWS, the eye connected to the awake hemisphere remains open, a state that may allow birds to visually navigate during sleep in flight. Bihemispheric SWS may also be possible during flight when constant visual monitoring of the environment is unnecessary. Nevertheless, the reduction in muscle tone that usually accompanies REM sleep makes it unlikely that birds enter this state in flight. Upon landing, birds may need to recover the components of sleep that are incompatible with flight. Periods of undisturbed postflight recovery sleep may be essential for maintaining adaptive brain function during wakefulness. The recent miniaturization of EEG recording devices now makes it possible to measure brain activity in flight. Determining if and how birds sleep in flight will contribute to our understanding of a largely unexplored aspect of avian behavior and may also provide insight into the function of sleep.

  9. Developing indicators for European birds

    PubMed Central

    Gregory, Richard D; van Strien, Arco; Vorisek, Petr; Gmelig Meyling, Adriaan W; Noble, David G; Foppen, Ruud P.B; Gibbons, David W

    2005-01-01

    The global pledge to deliver ‘a significant reduction in the current rate of biodiversity loss by 2010’ is echoed in a number of regional and national level targets. There is broad consensus, however, that in the absence of conservation action, biodiversity will continue to be lost at a rate unprecedented in the recent era. Remarkably, we lack a basic system to measure progress towards these targets and, in particular, we lack standard measures of biodiversity and procedures to construct and assess summary statistics. Here, we develop a simple classification of biodiversity indicators to assist their development and clarify purpose. We use European birds, as example taxa, to show how robust indicators can be constructed and how they can be interpreted. We have developed statistical methods to calculate supranational, multi-species indices using population data from national annual breeding bird surveys in Europe. Skilled volunteers using standardized field methods undertake data collection where methods and survey designs differ slightly across countries. Survey plots tend to be widely distributed at a national level, covering many bird species and habitats with reasonable representation. National species' indices are calculated using log-linear regression, which allows for plot turnover. Supranational species' indices are constructed by combining the national species' indices weighted by national population sizes of each species. Supranational, multi-species indicators are calculated by averaging the resulting indices. We show that common farmland birds in Europe have declined steeply over the last two decades, whereas woodland birds have not. Evidence elsewhere shows that the main driver of farmland bird declines is increased agricultural intensification. We argue that the farmland bird indicator is a useful surrogate for trends in other elements of biodiversity in this habitat. PMID:15814345

  10. Blood protozoa of imported birds.

    PubMed

    Manwell, R D; Rossi, G S

    1975-02-01

    Large numbers of birds, until recently, were brought into the United States each year. Countries of origin were varied, and included those of Australasia, Africa, South America, and the Caribbean islands, as well as other places. With them of course come their parasites, some of which may be potential pathogens to domestic avifauna. In part for this reason, a survey was undertaken of blood parasites of birds from pet shops and importers. So far a total of 1234 birds belonging to 186 species has been examined. Several new species and subspecies of avian Plasmodium have been found in the course of this study, including P. octamerium Manwell, 1968 in a Pintail Whydah, Vidua macoura, from Africa; P paranucleophilum Manwell & Sessler, 1971 in a South American tanager, Tachyphonus sp; and P. nucleophilum toucani Manwell & Sessler 1971 in a Swainson's Toucan, Ramphastos s. swainsonii. Plasmodium huffi Muniz, Soares & Battista is undoubtedly a synonym pro parte for the last. Plasmodium tenue Laveran & Maruliaz, long thought to be a synonym of Plasmodium vaughani Novy & MacNeal, was rediscovered and found to be a valid species. Plasmodium nucleophilum, infrequently seen in the New World, occurred in many Asian and African birds, and especially in starlings. Infections with other species of Plasmodium were common. Haemoproteus was the commonest blood parasite; Leucocytozoon was very rare as was Atoxoplasma (Lankesterella). The 2 families of birds best represented were the Fringillidae and the Psittacidae, but no blood parasites were seen in the latter. It is clear that imported birds are often infected with blood protozoa, some of which are unknown from native birds. PMID:804038

  11. Balance of the West Antarctic Ice Sheet

    NASA Technical Reports Server (NTRS)

    2002-01-01

    For several decades, measurements of the West Antarctic Ice Sheet showed it to be retreating rapidly. But new data derived from satellite-borne radar sensors show the ice sheet to be growing. Changing Antarctic ice sheets remains an area of high scientific interest, particularly in light of recent global warming concerns. These new findings are significant because scientists estimate that sea level would rise 5-6 meters (16-20 feet) if the ice sheet collapsed into the sea. Do these new measurements signal the end of the ice sheet's 10,000-year retreat? Or, are these new satellite data simply much more accurate than the sparse ice core and surface measurements that produced the previous estimates? Another possibility is that the ice accumulation may simply indicate that the ice sheet naturally expands and retreats in regular cycles. Cryologists will grapple with these questions, and many others, as they examine the new data. The image above depicts the region of West Antarctica where scientists measured ice speed. The fast-moving central ice streams are shown in red. Slower tributaries feeding the ice streams are shown in blue. Green areas depict slow-moving, stable areas. Thick black lines depict the areas that collect snowfall to feed their respective ice streams. Reference: Ian Joughin and Slawek Tulaczyk Science Jan 18 2002: 476-480. Image courtesy RADARSAT Antarctic Mapping Project

  12. Antarctic isolation: immune and viral studies

    NASA Technical Reports Server (NTRS)

    Tingate, T. R.; Lugg, D. J.; Muller, H. K.; Stowe, R. P.; Pierson, D. L.

    1997-01-01

    Stressful environmental conditions are a major determinant of immune reactivity. This effect is pronounced in Australian National Antarctic Research Expedition populations exposed to prolonged periods of isolation in the Antarctic. Alterations of T cell function, including depression of cutaneous delayed-type hypersensitivity responses and a peak 48.9% reduction of T cell proliferation to the mitogen phytohaemagglutinin, were documented during a 9-month period of isolation. T cell dysfunction was mediated by changes within the peripheral blood mononuclear cell compartment, including a paradoxical atypical monocytosis associated with altered production of inflammatory cytokines. There was a striking reduction in the production by peripheral blood mononuclear cells of the predominant pro-inflammatory monokine TNF-alpha and changes were also detected in the production of IL-1, IL-2, IL-6, IL-1ra and IL-10. Prolonged Antarctic isolation is also associated with altered latent herpesvirus homeostasis, including increased herpesvirus shedding and expansion of the polyclonal latent Epstein-Barr virus-infected B cell population. These findings have important long-term health implications.

  13. Update on terrestrial ages of Antarctic meteorites

    SciTech Connect

    Welten, K C; Nishiizumi, K; Caffee, M W

    2000-01-14

    Terrestrial ages of Antarctic meteorites are one of the few parameters that will help us to understand the meteorite concentration mechanism on blue-ice fields. Traditionally, terrestrial ages were determined on the basis of {sup 36}Cl in the metal phase, which has an uncertainty of about 70 ky. For young meteorites (< 40 ky), the terrestrial age is usually and most accurately determined using {sup 14}C in the stone phase. In recent years two methods have been developed which are independent of shielding effects, the {sup 10}Be-{sup 36}Cl/{sup 10}Be method and the {sup 41}Ca/{sup 36}Cl method. These methods have reduced the typical uncertainties in terrestrial ages by a factor of 2, to about 30 ky. The {sup 10}Be-{sup 36}Cl/{sup 10}Be method is quite dependent on the exposure age, which is unknown for most Antarctic meteorites. The authors therefore also attempt to use the relation between {sup 26}Al and {sup 36}Cl/{sup 26}Al to derive a terrestrial age less dependent on the exposure age. The authors have measured the concentrations of cosmogenic {sup 10}Be, {sup 26}Al and {sup 36}Cl in the metal phase of {approximately} 70 Antarctic meteorites, from more than 10 different ice-fields, including many new ones. They then discuss the trends in terrestrial ages of meteorites from different ice-fields.

  14. Antarctic Meteorite Classification and Petrographic Database Enhancements

    NASA Technical Reports Server (NTRS)

    Todd, N. S.; Satterwhite, C. E.; Righter, K.

    2012-01-01

    The Antarctic Meteorite collection, which is comprised of over 18,700 meteorites, is one of the largest collections of meteorites in the world. These meteorites have been collected since the late 1970 s as part of a three-agency agreement between NASA, the National Science Foundation, and the Smithsonian Institution [1]. Samples collected each season are analyzed at NASA s Meteorite Lab and the Smithsonian Institution and results are published twice a year in the Antarctic Meteorite Newsletter, which has been in publication since 1978. Each newsletter lists the samples collected and processed and provides more in-depth details on selected samples of importance to the scientific community. Data about these meteorites is also published on the NASA Curation website [2] and made available through the Meteorite Classification Database allowing scientists to search by a variety of parameters. This paper describes enhancements that have been made to the database and to the data and photo acquisition process to provide the meteorite community with faster access to meteorite data concurrent with the publication of the Antarctic Meteorite Newsletter twice a year.

  15. Adaptive-optics performance of Antarctic telescopes.

    PubMed

    Lawrence, Jon S

    2004-02-20

    The performance of natural guide star adaptive-optics systems for telescopes located on the Antarctic plateau is evaluated and compared with adaptive-optics systems operated with the characteristic mid-latitude atmosphere found at Mauna Kea. A 2-m telescope with tip-tilt correction and an 8-m telescope equipped with a high-order adaptive-optics system are considered. Because of the large isoplanatic angle of the South Pole atmosphere, the anisoplanatic error associated with an adaptive-optics correction is negligible, and the achievable resolution is determined only by the fitting error associated with the number of corrected wave-front modes, which depends on the number of actuators on the deformable mirror. The usable field of view of an adaptive-optics equipped Antarctic telescope is thus orders of magnitude larger than for a similar telescope located at a mid-latitude site; this large field of view obviates the necessity for multiconjugate adaptive-optics systems that use multiple laser guide stars. These results, combined with the low infrared sky backgrounds, indicate that the Antarctic plateau is the best site on Earth at which to perform high-resolution imaging with large telescopes, either over large fields of view or with appreciable sky coverage. Preliminary site-testing results obtained recently from the Dome Concordia station indicate that this site is far superior to even the South Pole. PMID:15008551

  16. Epidemiologic characterization of Colorado backyard bird flocks.

    PubMed

    Smith, Emily I; Reif, John S; Hill, Ashley E; Slota, Katharine E; Miller, Ryan S; Bjork, Kathe E; Pabilonia, Kristy L

    2012-06-01

    Backyard gallinaceous bird flocks may play an important role in the spread of infectious diseases within poultry populations as well as the transmission of zoonotic diseases to humans. An epidemiologic characterization was conducted of Colorado backyard flocks to gather information on general flock characteristics, human movement of birds, human-bird interaction, biosecurity practices, and flock health. Our results suggest that backyard poultry flocks in Colorado are small-sized flocks (68.6% of flocks had < 50 birds); consist primarily of layer chickens (85.49% of flocks), show chickens (32.18% of flocks), and waterfowl (34.07% of flocks); and are primarily owned for food (meat or egg) production for the family (86.44%) or as pet or hobby birds (42.27%). The backyard flock environment may promote bird-to-bird transmission as well as bird-to-human transmission of infectious disease. Birds are primarily housed with free access to the outside (96.85%), and many are moved from the home premises (46.06% within 1 yr). Human contact with backyard flocks is high, biosecurity practices are minimal, and bird health is negatively impacted by increased movement events. Increased knowledge of backyard bird characteristics and associated management practices can provide guidelines for the development of measures to decrease disease transmission between bird populations, decrease disease transmission from birds to humans, and increase the overall health of backyard birds. PMID:22856180

  17. 9 CFR 95.30 - Restrictions on entry of products and byproducts of poultry, game birds, or other birds from...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... byproducts of poultry, game birds, or other birds from regions where highly pathogenic avian influenza (HPAI... UNITED STATES § 95.30 Restrictions on entry of products and byproducts of poultry, game birds, or other..., including feathers, birds' nests, and bird trophies, of poultry, game birds, or other birds may be...

  18. 9 CFR 95.30 - Restrictions on entry of products and byproducts of poultry, game birds, or other birds from...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... byproducts of poultry, game birds, or other birds from regions where highly pathogenic avian influenza (HPAI... UNITED STATES § 95.30 Restrictions on entry of products and byproducts of poultry, game birds, or other..., including feathers, birds' nests, and bird trophies, of poultry, game birds, or other birds may be...

  19. 9 CFR 95.30 - Restrictions on entry of products and byproducts of poultry, game birds, or other birds from...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... byproducts of poultry, game birds, or other birds from regions where highly pathogenic avian influenza (HPAI... UNITED STATES § 95.30 Restrictions on entry of products and byproducts of poultry, game birds, or other..., including feathers, birds' nests, and bird trophies, of poultry, game birds, or other birds may be...

  20. Anticipatory Manoeuvres in Bird Flight

    PubMed Central

    Vo, Hong D.; Schiffner, Ingo; Srinivasan, Mandyam V.

    2016-01-01

    It is essential for birds to be agile and aware of their immediate environment, especially when flying through dense foliage. To investigate the type of visual signals and strategies used by birds while negotiating cluttered environments, we presented budgerigars with vertically oriented apertures of different widths. We find that, when flying through narrow apertures, birds execute their maneuvers in an anticipatory fashion, with wing closures, if necessary, occurring well in advance of the aperture. When passing through an aperture that is narrower than the wingspan, the birds close their wings at a specific, constant distance before the aperture, which is independent of aperture width. In these cases, the birds also fly significantly higher, possibly pre-compensating for the drop in altitude. The speed of approach is largely constant, and independent of the width of the aperture. The constancy of the approach speed suggests a simple means by which optic flow can be used to gauge the distance and width of the aperture, and guide wing closure. PMID:27270506

  1. Birds and polycyclic aromatic hydrocarbons

    USGS Publications Warehouse

    Albers, P.H.

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAH) are present throughout the global environment and are produced naturally and by activities of humans. Effects of PAH on birds have been determined by studies employing egg injection, egg immersion, egg shell application, single and multiple oral doses, subcutaneous injection, and chemical analysis of field-collected eggs and tissue. The four-to six-ring aromatic compounds are the most toxic to embryos, young birds, and adult birds. For embryos, effects include death, developmental abnormalities, and a variety of cellular and biochemical responses. For adult and young birds, effects include reduced egg production and hatching, increased clutch or brood abandonment, reduced growth, increased organweights, and a variety of biochemical responses. Trophic level accumulation is unlikely. Environmental exposure to PAH in areas of high human population or habitats affected by recent petroleum spills might be sufficient to adversely affect reproduction. Evidence of long-term effects of elevated concentrations of environmental PAH on bird populations is very limited and the mechanisms of effect are unclear.

  2. Anticipatory Manoeuvres in Bird Flight.

    PubMed

    Vo, Hong D; Schiffner, Ingo; Srinivasan, Mandyam V

    2016-01-01

    It is essential for birds to be agile and aware of their immediate environment, especially when flying through dense foliage. To investigate the type of visual signals and strategies used by birds while negotiating cluttered environments, we presented budgerigars with vertically oriented apertures of different widths. We find that, when flying through narrow apertures, birds execute their maneuvers in an anticipatory fashion, with wing closures, if necessary, occurring well in advance of the aperture. When passing through an aperture that is narrower than the wingspan, the birds close their wings at a specific, constant distance before the aperture, which is independent of aperture width. In these cases, the birds also fly significantly higher, possibly pre-compensating for the drop in altitude. The speed of approach is largely constant, and independent of the width of the aperture. The constancy of the approach speed suggests a simple means by which optic flow can be used to gauge the distance and width of the aperture, and guide wing closure. PMID:27270506

  3. Terrestrial Ages of Antarctic Meteorites- Update 1999

    NASA Technical Reports Server (NTRS)

    Nishiizumi, Kunihiko; Welten, K. C.; Caffee, Marc W.

    1999-01-01

    We are continuing our ongoing study of cosmogenic nuclides in Antarctic meteorites. In addition to the studies of exposure histories of meteorites, we study terrestrial ages and pairing of Antarctic meteorites and desert meteorites. Terrestrial ages of Antarctic meteorites provide information on meteorite accumulation mechanisms, mean weathering lifetimes, and influx rates. The determination of Cl-36(half-life=3.01 x 10(exp 5) y) terrestrial ages is one of our long-term on-going projects, however, in many instances neither Cl-36 or C-14 (5,730 y) yields an accurate terrestrial age. Using Ca-14 (1.04 x 10(exp 5) y) for terrestrial age determinations solves this problem by filling the c,ap in half-life between 14-C and Cl-36 ages. We are now applying the new Ca-41- Cl-36 terrestrial age method as well as the Cl-36-Be-10 method to Antarctic meteorites. Our measurements and C-14 terrestrial age determinations by the University of Arizona group are always complementary. We have measured Cl-36 in over 270 Antarctic meteorites since our previous compilation of terrestrial ages. Since a large number of meteorites have been recovered from many different icefields in Antarctica, we continue to survey the trends of terrestrial ages for different icefields. We have also measured detailed terrestrial ages vs. sample locations for Allan Hills, Elephant Moraine, and Lewis Cliff Icefields, where meteorites have been found with very long ages. The updated histograms of terrestrial ages of meteorites from the Allan Hills Main Icefield and Lewis Cliff Icefield are shown. These figures include C-14 ages obtained by the University of Arizona group. Pairs of meteorites are shown as one object for which the age is the average of all members of the same fall. The width of the bars represents 70,000 years, which was a typical uncertainty for Cl-36 ages. We reduced the uncertainty of terrestrial age determinations to approx. 40,000 years by using pairs of nuclides such as Ca-41-Cl-36 or Cl

  4. The ARM West Antarctic Radiation Experiment (AWARE)

    NASA Astrophysics Data System (ADS)

    Lubin, Dan; Bromwich, David; Vogelmann, Andrew; Verlinde, Johannes; Russell, Lynn

    2016-04-01

    West Antarctica is one of the most rapidly warming regions on Earth, and its changing climate in both atmosphere and ocean is linked to loss of Antarctic ice mass and global sea level rise. The specific mechanisms for West Antarctic Ice Sheet (WAIS) warming are not fully understood, but are hypothesized to involve linkage between moisture from Southern Ocean storm tracks and the surface energy balance over the WAIS, and related teleconnections with subtropical and tropical meteorology. This present lack of understanding has motivated a climate science and cloud physics campaign jointly supported by the US National Science Foundation (NSF) and Department of Energy (DOE), called the Atmospheric Radiation Measurement Program (ARM) West Antarctic Radiation Experiment (AWARE). The DOE's second ARM Mobile Facility (AMF2) was deployed to McMurdo Station on Ross Island in November 2015 and will operate through December 2016. The AMF2 includes (1) cloud research radars, both scanning and zenith, operating in the Ka- and X-bands, (2) high spectral resolution and polarized micropulse lidars, and (3) a suite of shortwave and longwave broadband and spectral radiometers. A second suite of instruments is deployed at the WAIS Divide Ice Camp on the West Antarctic plateau during December 2015 and January 2016. The WAIS instrument suite provides (1) measurement of all surface energy balance components, (2) a polarized micropulse lidar and shortwave spectroradiometer, (3) microwave total water column measurement, and (4) four times daily rawinsonde launches which are the first from West Antarctica since 1967. There is a direct linkage between the WAIS instrument suite and the AMF2 at McMurdo, in that air masses originating in Southern Ocean storm tracks that are driven up over the WAIS often subsequently descend over the Ross Ice Shelf and arrive at Ross Island. Preliminary data are already illustrating the prevalence of mixed-phase clouds and their role in the surface energy balance

  5. Geoethical Approach to Antarctic Subglacial Lakes Exploration

    NASA Astrophysics Data System (ADS)

    Talalay, Pavel; Markov, Alexey; Sysoev, Mikhail

    2014-05-01

    Antarctic subglacial aquatic environment have become of great interest to the science community because they may provide unique information about microbial evolution, the past climate of the Earth, and the formation of the Antarctic ice sheet. Nowadays it is generally recognized that a vast network of lakes, rivers, and streams exists thousands of meters beneath Antarctic Ice Sheets. Up to date only four boreholes accessed subglacial aquatic system but three of them were filled with high-toxic drilling fluid, and the subglacial water was contaminated. Two recent exploration programs proposed by UK and USA science communities anticipated direct access down to the lakes Ellsworth and Whillans, respectively, in the 2012/2013 Antarctic season. A team of British scientists and engineers engaged in the first attempt to drill into Lake Ellsworth but failed. US research team has successfully drilled through 800 m of Antarctic ice to reach a subglacial lake Whillans and retrieve water and sediment samples. Both activities used hot-water drilling technology to access lakes. Hot water is considered by the world science community as the most clean drilling fluid medium from the present point of view but it cannot solve environmental problems in total because hot-water even when heated to 90 °C, filtered to 0.2 μm, and UV treated at the surface could pick up microorganisms from near-surface snow and circulate them in great volume through the borehole. Another negative impact of hot-water circulation medium is thermal pollution of subglacial water. The new approach to Antarctic subglacial lakes exploration is presented by sampling technology with recoverable autonomous sonde which is equipped by two hot-points with heating elements located on the bottom and top sides of the sonde. All down-hole sonde components will be sterilized by combination of chemical wash, HPV and UV sterilization prior using. At the beginning of the summer season sonde is installed on the surface of the

  6. Water conservation in xerophilic birds.

    PubMed

    Skadhauge, E

    1976-08-01

    Adaptation of birds to dry climates involves decrease in relative evaporative water loss (mechanism unknown); decrease in GFR; and high urine osmolality in the dehydrated state in conjunction with cloacal resorption parameters, which allows the urine to enter the cloaca without a further water loss. The net result of the adaptations is such that the best adapted birds, such as the budgerygah (12) and the zebra finch (13) fed dry seeds alone can live without water. Similar features have been observed also in the best adapted desert rodents (27). Finally, birds tolerate a 7 to 13% increase in plasma osmolality (9). Tucker (28) has calculated that the budgerygah has fuel for 14 h flight; we have calculated that it also has water for 14 h (12) at neutral temperature and humidity. This is better than the Jumbo Jet, which can only fly for 12 h. PMID:977281

  7. 45 CFR 670.9 - Antarctic Conservation Act enforcement exception.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... out by an Antarctic Conservation Act Enforcement Officer (designated pursuant to 45 CFR 672.3) if... 45 Public Welfare 3 2010-10-01 2010-10-01 false Antarctic Conservation Act enforcement exception. 670.9 Section 670.9 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL...

  8. 45 CFR 670.9 - Antarctic Conservation Act enforcement exception.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... out by an Antarctic Conservation Act Enforcement Officer (designated pursuant to 45 CFR 672.3) if... 45 Public Welfare 3 2011-10-01 2011-10-01 false Antarctic Conservation Act enforcement exception. 670.9 Section 670.9 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL...

  9. 77 FR 5403 - Conservation of Antarctic Animals and Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-03

    ... From the Federal Register Online via the Government Publishing Office NATIONAL SCIENCE FOUNDATION 45 CFR Part 670 Conservation of Antarctic Animals and Plants AGENCY: National Science Foundation. ACTION: Final rule. SUMMARY: Pursuant to the Antarctic Conservation Act of 1978, The National...

  10. 45 CFR 670.9 - Antarctic Conservation Act enforcement exception.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... out by an Antarctic Conservation Act Enforcement Officer (designated pursuant to 45 CFR 672.3) if... 45 Public Welfare 3 2013-10-01 2013-10-01 false Antarctic Conservation Act enforcement exception. 670.9 Section 670.9 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL...

  11. 45 CFR 670.9 - Antarctic Conservation Act enforcement exception.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... out by an Antarctic Conservation Act Enforcement Officer (designated pursuant to 45 CFR 672.3) if... 45 Public Welfare 3 2012-10-01 2012-10-01 false Antarctic Conservation Act enforcement exception. 670.9 Section 670.9 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL...

  12. 45 CFR 670.9 - Antarctic Conservation Act enforcement exception.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... out by an Antarctic Conservation Act Enforcement Officer (designated pursuant to 45 CFR 672.3) if... 45 Public Welfare 3 2014-10-01 2014-10-01 false Antarctic Conservation Act enforcement exception. 670.9 Section 670.9 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL...

  13. Reaching for the Horizon: Enabling 21st Century Antarctic Science

    NASA Astrophysics Data System (ADS)

    Rogan-Finnemore, M.; Kennicutt, M. C., II; Kim, Y.

    2015-12-01

    The Council of Managers of National Antarctic Programs' (COMNAP) Antarctic Roadmap Challenges(ARC) project translated the 80 highest priority Antarctic and Southern Ocean scientific questionsidentified by the community via the SCAR Antarctic Science Horizon Scan into the highest prioritytechnological, access, infrastructure and logistics needs to enable the necessary research to answer thequestions. A workshop assembled expert and experienced Antarctic scientists and National AntarcticProgram operators from around the globe to discern the highest priority technological needs includingthe current status of development and availability, where the technologies will be utilized in the Antarctic area, at what temporal scales and frequencies the technologies will be employed,and how broadly applicable the technologies are for answering the highest priority scientific questions.Secondly the logistics, access, and infrastructure requirements were defined that are necessary todeliver the science in terms of feasibility including cost and benefit as determined by expected scientific return on investment. Finally, based on consideration of the science objectives and the mix oftechnologies implications for configuring National Antarctic Program logistics capabilities andinfrastructure architecture over the next 20 years were determined. In particular those elements thatwere either of a complexity, requiring long term investments to achieve and/or having an associated cost that realistically can only (or best) be achieved by international coordination, planning and partnerships were identified. Major trends (changes) in logistics, access, and infrastructure requirements were identified that allow for long-term strategic alignment of international capabilities, resources and capacity. The outcomes of this project will be reported.

  14. The Superconducting Bird: A Didactical Toy.

    ERIC Educational Resources Information Center

    Guarner, E.; Sanchez, A. M.

    1992-01-01

    Describes the design of the superconducting bird, a device to demonstrate the phenomenon of superconductivity. Discusses the utilization of the device as an example of a motor and compares it to the toy called the drinking bird. (MDH)

  15. Solutions to problems of weathering in Antarctic eucrites

    NASA Technical Reports Server (NTRS)

    Strait, Melissa M.

    1990-01-01

    Neutron activation analysis was performed for major and trace elements on a suite of eucrites from both Antarctic and non-Antarctic sources. The chemistry was examined to see if there was an easy way to distinguish Antarctic eucrites that had been disturbed in their trace elements systematics from those that had normal abundances relative to non-Antarctic eucrites. There was no simple correlation found, and identifying the disturbed meteorites still remains a problem. In addition, a set of mineral separates from an eucrite were analyzed. The results showed no abnormalities in the chemistry and provides a possible way to use Antarctic eucrites that were disturbed in modelling of the eucrite parent body.

  16. Interagency cooperative scientific program to investigate antarctic ozone hole

    SciTech Connect

    Not Available

    1987-09-01

    NASA, The Department of Commerce National Oceanic and Atmospheric Administration, the National Science Foundation and its National Center for Atmospheric Research, and the Chemical Manufacturer's Association have announced a cooperative investigation of the Antarctic ozone hole. The Airborne Antarctic Ozone Experiment will fly specially instrumented NASA ER-2 and DC-8 aircraft into the Antarctic ozone hole from August 17 through September 29. The experiments have been designed not only to test existing Antarctic ozone hole theories but to provide for a wide base of high quality atmospheric data in the event that none of the current hypotheses proves to be adequate. This experiment is prompted by recent observations that have shown a dramatic and unexpected downward trend in the amount of ozone in a column of air over the Antarctic in the period between late winter and early spring.

  17. DEVELOPMENT OF A BIRD INTEGRITY INDEX: USING BIRD ASSEMBLAGES AS INDICATORS OF RIPARIAN CONDITION

    EPA Science Inventory

    We describe the development of a Bird Integrity Index (BII) that uses bird assemblage information to assess human impacts on 13 stream reaches in the Willamette Valley, Oregon. We used bird survey field data to test 62 candidate metrics representing aspects of bird taxonomic ric...

  18. Birds and Bird Habitat: What Are the Risks from Industrial Wind Turbine Exposure?

    ERIC Educational Resources Information Center

    Sprague, Terry; Harrington, M. Elizabeth; Krogh, Carmen M. E.

    2011-01-01

    Bird kill rate and disruption of habitat has been reported when industrial wind turbines are introduced into migratory bird paths or other environments. While the literature could be more complete regarding the documentation of negative effects on birds and bird habitats during the planning, construction, and operation of wind power projects,…

  19. Numerical model of circumpolar Antarctic ice shelves

    SciTech Connect

    Johnson, R.C.

    1985-01-01

    Extensive floating ice shelves in the Antarctic have been proposed to explain the discrepancies between Pleistocene high sea levels shown by dated coral reefs and coeval low sea levels inferred from glacial ice volumes calculated from oxygen isotope ratios in deep sea cores. A numerical model using the floating shelf creep analysis of Weertman (1957) has provided a plausible basis for the acceptance of such shelves. Shelf outer limits were set at 55/sup 0/S in East Antarctica and 58/sup 0/S in West Antarctica, based in part on diatom-deficient deep sea sediments deposited prior to the Holocene. Precipitation varied from 10 gm cm/sup -2/yr/sup -1/ at 75/sup 0/S to 80 gm cm/sup -2/yr/sup -1/ at 55/sup 0/S. Mean air temperatures varied from -35/sup 0/C at the 75/sup 0/S coast to -17/sup 0/C at the outer limits. Isotope ratios were those of present Antarctic precipitation at corresponding model shelf temperatures. In the calculation, a steady state is assumed. Integration begins at the coast with summation over successive years as creep and continental ice discharge move the integration element to the outer limits. The oceanic oxygen isotope ratio change required by the discrepancies in the record is 0.40 to 0.50 ppmil. Using the flow law constant of 4.2 and a creep activation energy of 134 kjoules mol/sup -1/, the resulting change is 0.44 ppmil. Difference results reflect the uncertainties associated with the critical creep constants used in the modeling. Nevertheless, the results suggest that a quantity of Antarctic shelf ice comparable to ice volumes in major Northern glacial areas existed at times during the Pleistocene.

  20. Ocean processes at the Antarctic continental slope.

    PubMed

    Heywood, Karen J; Schmidtko, Sunke; Heuzé, Céline; Kaiser, Jan; Jickells, Timothy D; Queste, Bastien Y; Stevens, David P; Wadley, Martin; Thompson, Andrew F; Fielding, Sophie; Guihen, Damien; Creed, Elizabeth; Ridley, Jeff K; Smith, Walker

    2014-07-13

    The Antarctic continental shelves and slopes occupy relatively small areas, but, nevertheless, are important for global climate, biogeochemical cycling and ecosystem functioning. Processes of water mass transformation through sea ice formation/melting and ocean-atmosphere interaction are key to the formation of deep and bottom waters as well as determining the heat flux beneath ice shelves. Climate models, however, struggle to capture these physical processes and are unable to reproduce water mass properties of the region. Dynamics at the continental slope are key for correctly modelling climate, yet their small spatial scale presents challenges both for ocean modelling and for observational studies. Cross-slope exchange processes are also vital for the flux of nutrients such as iron from the continental shelf into the mixed layer of the Southern Ocean. An iron-cycling model embedded in an eddy-permitting ocean model reveals the importance of sedimentary iron in fertilizing parts of the Southern Ocean. Ocean gliders play a key role in improving our ability to observe and understand these small-scale processes at the continental shelf break. The Gliders: Excellent New Tools for Observing the Ocean (GENTOO) project deployed three Seagliders for up to two months in early 2012 to sample the water to the east of the Antarctic Peninsula in unprecedented temporal and spatial detail. The glider data resolve small-scale exchange processes across the shelf-break front (the Antarctic Slope Front) and the front's biogeochemical signature. GENTOO demonstrated the capability of ocean gliders to play a key role in a future multi-disciplinary Southern Ocean observing system. PMID:24891389

  1. Ocean processes at the Antarctic continental slope

    PubMed Central

    Heywood, Karen J.; Schmidtko, Sunke; Heuzé, Céline; Kaiser, Jan; Jickells, Timothy D.; Queste, Bastien Y.; Stevens, David P.; Wadley, Martin; Thompson, Andrew F.; Fielding, Sophie; Guihen, Damien; Creed, Elizabeth; Ridley, Jeff K.; Smith, Walker

    2014-01-01

    The Antarctic continental shelves and slopes occupy relatively small areas, but, nevertheless, are important for global climate, biogeochemical cycling and ecosystem functioning. Processes of water mass transformation through sea ice formation/melting and ocean–atmosphere interaction are key to the formation of deep and bottom waters as well as determining the heat flux beneath ice shelves. Climate models, however, struggle to capture these physical processes and are unable to reproduce water mass properties of the region. Dynamics at the continental slope are key for correctly modelling climate, yet their small spatial scale presents challenges both for ocean modelling and for observational studies. Cross-slope exchange processes are also vital for the flux of nutrients such as iron from the continental shelf into the mixed layer of the Southern Ocean. An iron-cycling model embedded in an eddy-permitting ocean model reveals the importance of sedimentary iron in fertilizing parts of the Southern Ocean. Ocean gliders play a key role in improving our ability to observe and understand these small-scale processes at the continental shelf break. The Gliders: Excellent New Tools for Observing the Ocean (GENTOO) project deployed three Seagliders for up to two months in early 2012 to sample the water to the east of the Antarctic Peninsula in unprecedented temporal and spatial detail. The glider data resolve small-scale exchange processes across the shelf-break front (the Antarctic Slope Front) and the front's biogeochemical signature. GENTOO demonstrated the capability of ocean gliders to play a key role in a future multi-disciplinary Southern Ocean observing system. PMID:24891389

  2. Bird Cherry-Oat Aphid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    • The bird cherry-oat aphid (Rhopalosiphum padi) is an important vector of barley yellow dwarf viruses that affect wheat and other small-grain crops, but the aphid may also cause direct feeding damage to wheat. • Various plant-resistance modalities and natural enemies are not equally applicable in s...

  3. Managing a Bird Flu Pandemic

    ERIC Educational Resources Information Center

    Stover, Del

    2006-01-01

    Concern about a possible bird flu pandemic has grown in the medical community with the spread of the avian flu virus around the globe. Health officials say there is no immediate threat but add that an influenza pandemic occurs every 30 to 40 years, and prudence demands planning now. That planning will increasingly involve local school officials,…

  4. Illinois Birds. Nature Discovery I.

    ERIC Educational Resources Information Center

    Stone, Sally F.

    The birds of Illinois and their particular habitats are explored in this guide which is a part of a series of Nature Discovery publications. The materials are designed to directly supplement the natural science curricula and to complement other subject areas including social studies, language arts, music, and art. The program is formated for…

  5. The Bird Box Survey Project

    ERIC Educational Resources Information Center

    Willis, Patrick

    2014-01-01

    When high school students are asked what's the best part of science class, many will say it's the field trips. Students enjoy engaging in authentic, community-based science outside the classroom. To capitalize on this, Patrick Willis created the Bird Box Survey Project for his introductory field biology class. The project takes students…

  6. Examining Differences in Arctic and Antarctic Sea Ice Change

    NASA Astrophysics Data System (ADS)

    Nghiem, S. V.; Rigor, I. G.; Clemente-Colon, P.; Neumann, G.; Li, P.

    2015-12-01

    The paradox of the rapid reduction of Arctic sea ice versus the stability (or slight increase) of Antarctic sea ice remains a challenge in the cryospheric science research community. Here we start by reviewing a number of explanations that have been suggested by different researchers and authors. One suggestion is that stratospheric ozone depletion may affect atmospheric circulation and wind patterns such as the Southern Annular Mode, and thereby sustaining the Antarctic sea ice cover. The reduction of salinity and density in the near-surface layer may weaken the convective mixing of cold and warmer waters, and thus maintaining regions of no warming around the Antarctic. A decrease in sea ice growth may reduce salt rejection and upper-ocean density to enhance thermohalocline stratification, and thus supporting Antarctic sea ice production. Melt water from Antarctic ice shelves collects in a cool and fresh surface layer to shield the surface ocean from the warmer deeper waters, and thus leading to an expansion of Antarctic sea ice. Also, wind effects may positively contribute to Antarctic sea ice growth. Moreover, Antarctica lacks of additional heat sources such as warm river discharge to melt sea ice as opposed to the case in the Arctic. Despite of these suggested explanations, factors that can consistently and persistently maintains the stability of sea ice still need to be identified for the Antarctic, which are opposed to factors that help accelerate sea ice loss in the Arctic. In this respect, using decadal observations from multiple satellite datasets, we examine differences in sea ice properties and distributions, together with dynamic and thermodynamic processes and interactions with land, ocean, and atmosphere, causing differences in Arctic and Antarctic sea ice change to contribute to resolving the Arctic-Antarctic sea ice paradox.

  7. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  8. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  9. 14 CFR 35.36 - Bird impact.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bird impact. 35.36 Section 35.36... STANDARDS: PROPELLERS Tests and Inspections § 35.36 Bird impact. The applicant must demonstrate, by tests or... 4-pound bird at the critical location(s) and critical flight condition(s) of a typical...

  10. 14 CFR 35.36 - Bird impact.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bird impact. 35.36 Section 35.36... STANDARDS: PROPELLERS Tests and Inspections § 35.36 Bird impact. The applicant must demonstrate, by tests or... 4-pound bird at the critical location(s) and critical flight condition(s) of a typical...

  11. 14 CFR 35.36 - Bird impact.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bird impact. 35.36 Section 35.36... STANDARDS: PROPELLERS Tests and Inspections § 35.36 Bird impact. The applicant must demonstrate, by tests or... 4-pound bird at the critical location(s) and critical flight condition(s) of a typical...

  12. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  13. Bird streamer flashovers on FPL transmission lines

    SciTech Connect

    Burnham, J.T.

    1995-04-01

    FPL transmission lines with excessive unknown cause outages were investigated and determined to have experiences bird streamer flashovers. Findings are extended to similar lines and the frequency of bird streamer occurrences are estimated. Outage patterns associated with bird streamer flashovers are presented.

  14. 14 CFR 35.36 - Bird impact.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bird impact. 35.36 Section 35.36... STANDARDS: PROPELLERS Tests and Inspections § 35.36 Bird impact. The applicant must demonstrate, by tests or... 4-pound bird at the critical location(s) and critical flight condition(s) of a typical...

  15. 14 CFR 35.36 - Bird impact.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bird impact. 35.36 Section 35.36... STANDARDS: PROPELLERS Tests and Inspections § 35.36 Bird impact. The applicant must demonstrate, by tests or... 4-pound bird at the critical location(s) and critical flight condition(s) of a typical...

  16. The Physics of Bird Flight: An Experiment

    ERIC Educational Resources Information Center

    Mihail, Michael D.; George, Thomas F.; Feldman, Bernard J.

    2008-01-01

    This article describes an experiment that measures the forces acting on a flying bird during takeoff. The experiment uses a minimum of equipment and only an elementary knowledge of kinematics and Newton's second law. The experiment involves first digitally videotaping a bird during takeoff, analyzing the video to determine the bird's position as a…

  17. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  18. 14 CFR 29.631 - Bird strike.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bird strike. 29.631 Section 29.631... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.631 Bird strike. The... safe landing (for Category B) after impact with a 2.2-lb (1.0 kg) bird when the velocity of...

  19. Birds Make Learning Easy. Science Sampler

    ERIC Educational Resources Information Center

    Parott, Joanne

    2004-01-01

    Through this middle school curriculum, students observe bird feeders outside their classrooms, learn to identify birds that visit, and use a simple protocol for counting the birds and collecting other data before sending it to Cornell scientists via the Internet. The activities within the curriculum are inquiry-based and interdisciplinary. This…

  20. Neoplasms identified in free-flying birds

    USGS Publications Warehouse

    Siegfried, L.M.

    1983-01-01

    Nine neoplasms were identified in carcasses of free-flying wild birds received at the National Wildlife Health Laboratory; gross and microscopic descriptions are reported herein. The prevalence of neoplasia in captive and free-flying birds is discussed, and lesions in the present cases are compared with those previously described in mammals and birds.

  1. Terrestrial and exposure histories of Antarctic meteorites

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.

    1986-01-01

    Records of cosmogenic effects were studied in a large suite of Antarctic meteorites. The cosmogenic nuclide measurements together with cosmic ray track measurements on Antartic meteorites provide information such as exposure age, terrestrial age, size and depth in meteoroid or parent body, influx rate in the past, and pairing. The terrestrail age is the time period between the fall of the meteorite on the Earth and the present. To define terrestrial age, two or more nuclides with different half-lives and possibly noble gases are required. The cosmogenic radionuclides used are C-14, Kr-81, Cl-36, Al-26, Be-10, Mn-53, and K-40.

  2. Meteorites and the Antarctic ice sheet

    NASA Technical Reports Server (NTRS)

    Cassidy, W. A.

    1986-01-01

    The majority of the meteorite finds were located in the Allan Hills site. All the expected goals involving the recovery of rare or previously unknown types of meteorites, and even the recovery of lunar ejecta, were realized. The relationship between these remarkable concentrations of meteorites and the Antarctic ice sheet itself were less well documented. Ice flow vector studies were made and concentration models were proposed. Earlier estimates of the abundances of meteorite types were based on the number of falls in the world collections. The accumulated data and the future collected data will allow more reliable estimates of the source region of most meteorites.

  3. Siderotyping of Antarctic fluorescent Pseudomonas strains.

    PubMed

    Geoffroy, V A; Meyer, J M

    2004-07-01

    Five fluorescent Pseudomonas strains isolated from Antarctica have been previously recognized as producing three structurally different pyoverdines. In the present work, siderotyping procedures have been used to classify these strains, together with 1282 isolates of different origins, into siderovars. The strain biodiversity encountered within each siderovar, as well as the potential taxonomic value of the siderovars, are described and discussed. It is concluded that a majority of antarctic strains are commonly distributed worldwide. One strain, however, presenting a particular pyoverdine structure found in a unique other isolate, was apparently much more specific to cold environment. PMID:15559975

  4. Measurements of ethane in Antarctic ice cores

    NASA Astrophysics Data System (ADS)

    Verhulst, K. R.; Fosse, E. K.; Aydin, K. M.; Saltzman, E. S.

    2011-12-01

    Ethane is one of the most abundant hydrocarbons in the atmosphere. The major ethane sources are fossil fuel production and use, biofuel combustion, and biomass-burning emissions and the primary loss pathway is via reaction with OH. A paleoatmospheric ethane record would be useful as a tracer of biomass-burning emissions, providing a constraint on past changes in atmospheric methane and methane isotopes. An independent biomass-burning tracer would improve our understanding of the relationship between biomass burning and climate. The mean annual atmospheric ethane level at high southern latitudes is about 230 parts per trillion (ppt), and Antarctic firn air measurements suggest that atmospheric ethane levels in the early 20th century were considerably lower (Aydin et al., 2011). In this study, we present preliminary measurements of ethane (C2H6) in Antarctic ice core samples with gas ages ranging from 0-1900 C.E. Samples were obtained from dry-drilled ice cores from South Pole and Vostok in East Antarctica, and from the West Antarctic Ice Sheet Divide (WAIS-D). Gases were extracted from the ice by melting under vacuum in a glass vessel sealed by indium wire and were analyzed using high resolution GC/MS with isotope dilution. Ethane levels measured in ice core samples were in the range 100-220 ppt, with a mean of 157 ± 45 ppt (n=12). System blanks contribute roughly half the amount of ethane extracted from a 300 g ice core sample. These preliminary data exhibit a temporal trend, with higher ethane levels from 0-900 C.E., followed by a decline, reaching a minimum between 1600-1700 C.E. These trends are consistent with variations in ice core methane isotopes and carbon monoxide isotopes (Ferretti et al., 2005, Wang et al., 2010), which indicate changes in biomass burning emissions over this time period. These preliminary data suggest that Antarctic ice core bubbles contain paleoatmospheric ethane levels. With further improvement of laboratory techniques it appears

  5. Ultraviolet radiation levels during the Antarctic spring

    NASA Technical Reports Server (NTRS)

    Frederick, John E.; Snell, Hilary E.

    1988-01-01

    The decrease in atmospheric ozone over Antarctica during spring implies enhanced levels of ultraviolet (UV) radiation received at the earth's surface. Model calculations show that UV irradiances encountered during the occurrence of an Antarctic 'ozone hole' remain less than those typical of a summer solstice at low to middle latitudes. However, the low ozone amounts observed in October 1987 imply biologically effective irradiances for McMurdo Station, Antarctica, that are comparable to or greater than those for the same location at December solstice. Life indigenous to Antarctica thereby experiences a greatly extended period of summerlike UV radiation levels.

  6. Automatic focusing system of BSST in Antarctic

    NASA Astrophysics Data System (ADS)

    Tang, Peng-Yi; Liu, Jia-Jing; Zhang, Guang-yu; Wang, Jian

    2015-10-01

    Automatic focusing (AF) technology plays an important role in modern astronomical telescopes. Based on the focusing requirement of BSST (Bright Star Survey Telescope) in Antarctic, an AF system is set up. In this design, functions in OpenCV is used to find stars, the algorithm of area, HFD or FWHM are used to degree the focus metric by choosing. Curve fitting method is used to find focus position as the method of camera moving. All these design are suitable for unattended small telescope.

  7. The Antarctic Ozone Hole: An Update

    NASA Technical Reports Server (NTRS)

    Douglass, Anne R.; Newman, Paul A.; Solomon, Susan

    2014-01-01

    The stratospheric ozone hole, an annual occurrence during austral spring, is caused by heterogeneous conversion of hydrogen chloride and chlorine nitrate to chlorine radicals. These reactions take place of polar stratospheric cloud particles in the cold, isolate Antarctic winter vortex. The chlorine radicals participate in chemical reactions that rapidly deplete ozone when sunlight returns at the end of polar night. International agreements eliminated production of the culprit anthropogenic chlorofluorocarbons in the late 1990s, but due to their long stratospheric lifetime (50-100 years), the ozone hole will continue its annual appearance for years to come.

  8. Temperature response of Antarctic cryptoendolithic photosynthetic microorganisms

    NASA Technical Reports Server (NTRS)

    Ocampo-Friedmann, R.; Meyer, M. A.; Chen, M.; Friedmann, E. I.

    1988-01-01

    Growth responses to temperatures between 12.5 [degrees] C and 25 degrees C were determined for five photosynthetic microorganisms isolated from the Ross Desert cryptoendolithic community. Among eukaryotic algae, two strains of Trebouxia sp. have an upper temperature limit of 20 degrees C, and two strains of Hemichloris antarctica of 25 degrees C. The cyanobacterium Chroococcidiopsis sp., in contrast, grows at temperatures above 25 degrees C. These and earlier studies suggest that the eukaryotic algae of the Antarctic cryptoendolithic community have an upper temperature limit near 25 degrees C.

  9. The 1991 Antarctic ozone hole - TOMS observations

    NASA Technical Reports Server (NTRS)

    Krueger, Arlin; Schoeberl, Mark; Newman, Paul; Stolarski, Richard

    1992-01-01

    The 1991 Antarctic springtime ozone decline, as measured by the Total Ozone Mapping Spectrometer (TOMS), was similar to those of earlier deep ozone hole years, 1987, 1989, and 1990. The minimum total ozone value was recorded on October 5, 1991 at 108 Dobson units near the South Pole. This was 8 DU lower than in any of the earlier years. Four of the last five years have exhibited an extensive, deep ozone hole. The area of the hole was about the same as in 1987, 1989, and 1990. The recovery of the low total ozone values occurred in mid-November as the polar vortex broke up.

  10. Portable Habitat for Antarctic Scientific Research (PHASR)

    NASA Technical Reports Server (NTRS)

    Griswold, Samantha S.

    1992-01-01

    The Portable Habitat for Antarctic Scientific Research, PHASR, is designed as a versatile, general purpose habitat system that addresses the problem of functional space and environmental soundness in a partially fabric-covered shelter. PHASR is used for remote field site applications that can be quickly deployed. PHASR will also provide four scientists with a comfortable and efficient use of interior space. PHASR is a NASA/USRA Advanced Design Program project conducted at the University of Houston College of Architecture, Sasadawa International Center for Space Architecture (SICSA). This report is prepared for NASA/USRA.

  11. Population status of North American grassland birds from the North American Breeding Bird Survey

    USGS Publications Warehouse

    Peterjohn, B.; Sauer, J.R.

    1999-01-01

    We summarize population trends for grassland birds from 1966 to 1996 using data from the North American Breeding Bird Survey. Collectively, grassland birds showed the smallest percentage of species that increased of any Breeding Bird Survey bird group, and population declines prevailed throughout most of North America. Although 3 grassland bird species experienced significant population increases between 1966 and 1996, 13 species declined significantly and 9 exhibited non-significant trend estimates. We summarize the temporal and geographic patterns of the trends for grassland bird species and discuss factors that have contributed to these trends.

  12. DNA barcoding of Dutch birds

    PubMed Central

    Aliabadian, Mansour; Beentjes, Kevin K.; Roselaar, C.S. (Kees); van Brandwijk, Hans; Nijman, Vincent; Vonk, Ronald

    2013-01-01

    Abstract The mitochondrial cytochrome c oxidase subunit I (COI) can serve as a fast and accurate marker for the identification of animal species, and has been applied in a number of studies on birds. We here sequenced the COI gene for 387 individuals of 147 species of birds from the Netherlands, with 83 species being represented by > 2 sequences. The Netherlands occupies a small geographic area and 95% of all samples were collected within a 50 km radius from one another. The intraspecific divergences averaged 0.29% among this assemblage, but most values were lower; the interspecific divergences averaged 9.54%. In all, 95% of species were represented by a unique barcode, with 6 species of gulls and skua (Larus and Stercorarius) having at least one shared barcode. This is best explained by these species representing recent radiations with ongoing hybridization. In contrast, one species, the Lesser Whitethroat Sylvia curruca showed deep divergences, averaging 5.76% and up to 8.68% between individuals. These possibly represent two distinct taxa, S. curruca and S. blythi, both clearly separated in a haplotype network analysis. Our study adds to a growing body of DNA barcodes that have become available for birds, and shows that a DNA barcoding approach enables to identify known Dutch bird species with a very high resolution. In addition some species were flagged up for further detailed taxonomic investigation, illustrating that even in ornithologically well-known areas such as the Netherlands, more is to be learned about the birds that are present. PMID:24453549

  13. Late Quaternary environmental changes in Marguerite Bay, Antarctic Peninsula, inferred from lake sediments and raised beaches

    NASA Astrophysics Data System (ADS)

    Hodgson, Dominic A.; Roberts, Stephen J.; Smith, James A.; Verleyen, Elie; Sterken, Mieke; Labarque, Minke; Sabbe, Koen; Vyverman, Wim; Allen, Claire S.; Leng, Melanie J.; Bryant, Charlotte

    2013-05-01

    . Chaetoceros resting spores suggest high productivity and stratified surface waters in The Narrows after 8850 (9260-8480) cal yr BP and beach clasts provide evidence of a period of increased wave energy at approximately 8000 yr BP. Lake sediment and beach data suggest an extended period of regional warming sometime between 6200 and 2030 cal yr BP followed by the onset of Neoglacial conditions from 2630 and 2030 cal yr BP in Narrows Lake and Col Lake 1, respectively. Diatom and δ13C vs C/N and macrofossil evidence suggest a potential increase in the number of birds and seals visiting the Narrows Lake catchment sometime after 2100 (2250-2000) cal yr BP, with enhanced nutrient enrichment evident after 1150 (1230-1080) cal yr BP, and particularly from c. 460 (540-380) cal yr BP. A very recent increase in Gomphonema species and organic carbon in the top centimetre of the Narrows Lake sediment core after c. 410 (490-320) cal yr BP, and increased sedimentation rates in the Col Lake 1 sediment core, after c. 400 (490-310) cal yr BP may be a response to the regional late-Holocene warming of the Antarctic Peninsula.

  14. Adaptations to polar life in mammals and birds.

    PubMed

    Blix, Arnoldus Schytte

    2016-04-15

    This Review presents a broad overview of adaptations of truly Arctic and Antarctic mammals and birds to the challenges of polar life. The polar environment may be characterized by grisly cold, scarcity of food and darkness in winter, and lush conditions and continuous light in summer. Resident animals cope with these changes by behavioural, physical and physiological means. These include responses aimed at reducing exposure, such as 'balling up', huddling and shelter building; seasonal changes in insulation by fur, plumage and blubber; and circulatory adjustments aimed at preservation of core temperature, to which end the periphery and extremities are cooled to increase insulation. Newborn altricial animals have profound tolerance to hypothermia, but depend on parental care for warmth, whereas precocial mammals are well insulated and respond to cold with non-shivering thermogenesis in brown adipose tissue, and precocial birds shiver to produce heat. Most polar animals prepare themselves for shortness of food during winter by the deposition of large amounts of fat in times of plenty during autumn. These deposits are governed by a sliding set-point for body fatness throughout winter so that they last until the sun reappears in spring. Polar animals are, like most others, primarily active during the light part of the day, but when the sun never sets in summer and darkness prevails during winter, high-latitude animals become intermittently active around the clock, allowing opportunistic feeding at all times. The importance of understanding the needs of the individuals of a species to understand the responses of populations in times of climate change is emphasized. PMID:27103673

  15. Monitoring bird populations with Breeding Bird Survey and atlas data

    USGS Publications Warehouse

    Robbins, C.S.; Droege, S.; Sauer, J.R.

    1989-01-01

    The principal means of monitoring avian species in North America since 1966 is the Breeding Bird Survey (BBS). Nearly 2000 random roadside rouleS of 50 3-minule stops each are run once each summer by experienced observers. Two-year and 10ng-lerm population trends have been calculated for 250 of the more common species. We show how Breeding Bird Atlas dala for lWO periods of time can also be used to calculale population nends, and we compare atlas neRds with those from the BBS. If coverage is inlensive and consistent belWeen time periods, atlas dala may be useful for monitoring species that are not adequalely sampled by the BBS.

  16. Mapping Antarctic grounding lines from Cryosat-2

    NASA Astrophysics Data System (ADS)

    Wouters, B.; Bamber, J. L.

    2014-12-01

    The grounding zone (GZ) of the Antarctic ice sheet is a critical boundary for assessing the mass of ice leaving the continent and the stability (or lack thereof) of the inland, grounded ice sheet. It marks the transition between ice that can contribute to sea level and that which already has. Ice shelf basal melt rates are a maximum close the GZ and can have an important influence on inland flow. Changes in the position of the GZ for an ice stream resting on a bed with a retrograde slope (deepening inland) can provide an early warning of an instability in flow or state transition. Several methods exists to monitor the GZ, however, to date, there has been no method for routinely and regularly monitoring the GZ, nor any method that can be applied unambiguously across its entirety around Antarctica. The CryoSat-2 mission provides year-round coverage of the ice sheets, at a high spatial resolution. On the Antarctic ice shelves, the 369 day repeat period of the observations leads to aliasing of tidal motion induced by ocean tides, resulting in distinct patterns in the CryoSat-2 elevation measurements. Here, we focus on the Filchner-Ronne ice shelf to demonstrate the potential of the Cryosat-2 observations to map the GZ, and compare our results with existing GZ estimates.

  17. Longitudinal surface structures (flowstripes) on Antarctic glaciers

    NASA Astrophysics Data System (ADS)

    Glasser, N. F.; Gudmundsson, G. H.

    2012-03-01

    Longitudinal surface structures ("flowstripes") are common on many glaciers but their origin and significance are poorly understood. In this paper we present observations of the development of these longitudinal structures from four different Antarctic glacier systems; the Lambert Glacier/Amery Ice Shelf area, the Taylor and Ferrar Glaciers in the Ross Sea sector, Crane and Jorum Glaciers (ice-shelf tributary glaciers) on the Antarctic Peninsula, and the onset zone of a tributary to the Recovery Glacier Ice Stream in the Filchner Ice Shelf area. Mapping from optical satellite images demonstrates that longitudinal surface structures develop in two main situations: (1) as relatively wide flow stripes within glacier flow units and (2) as relatively narrow flow stripes where there is convergent flow around nunataks or at glacier confluence zones. Our observations indicate that the confluence features are narrower, sharper, and more clearly defined features. They are characterised by linear troughs or depressions on the ice surface and are much more common than the former type. Longitudinal surface structures within glacier flow units have previously been explained as the surface expression of localised bed perturbations but a universal explanation for those forming at glacier confluences is lacking. Here we propose that these features are formed at zones of ice acceleration and extensional flow at glacier confluences. We provide a schematic model for the development of longitudinal surface structures based on extensional flow that can explain their ridge and trough morphology as well as their down-ice persistence.

  18. Correlation of Windspeed and Antarctic Surface Roughness

    NASA Astrophysics Data System (ADS)

    Stockham, Mark; Anita Collaboration

    2015-04-01

    When electromagnetic waves interact with a media interface the transmitted and reflected portions of the incoming wave depend on the incident angle of the wave and wavelength (as well as the material properties of the media). The roughness of the surface of Antarctica affects the radio frequency signals received by airborne experiments, such as the balloon-borne experiment ANITA (ANtarctic Impulsive Transient Antenna) which observes the reflected radio waves from cosmic ray-induced extensive air showers (EAS). Roughness of a given scale can cause decoherence of the reflected signal and is an important effect to understand when estimating the amplitude of the incoming wave based on the reflected wave. It is challenging to get a survey of surface roughness over many of the areas that these experiments are likely to pass over. Correlating historical wind speed records with statistical roughness as observed by the backscatter of satellite [Rémy F, Parouty S. Remote Sensing. 2009] and airborne experiments operating at different frequencies can possibly be used to predict time-dependent surface roughness with surface wind speed as the input. These correlations will be presented for a variety of areas on the Antarctic ice shelf. NASA Grant NNX11AC47G.

  19. When Will the Antarctic Ozone Hole Recover?

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Steve

    2005-01-01

    The Antarctic ozone hole develops each year and culminates by early Spring. Antarctic ozone values have been monitored since 1979 using satellite observations from the TOMS instrument. The severity of the hole has been assessed from TOMS using the minimum total ozone value from the October monthly mean (depth of the hole) and by calculating the average size during the September-October period. Ozone is mainly destroyed by halogen catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this presentation, we show the relationships of halogens and temperature to both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. Using projections of halogen levels combined with age-of-air estimates, we find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. We will show estimates of both when the ozone hole will begin to show first signs of recovery, and when the hole will fully recover to pre-1980 levels.

  20. Recovery of the Antarctic Ozone Hole

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Steve; Schauffler, Sue; Stolarski, Richard S.; Douglass, Anne R.; Pawson, Steven; Nielsen, J. Eric

    2006-01-01

    The Antarctic ozone hole develops each year and culminates by early Spring. Antarctic ozone values have been monitored since 1979 using satellite observations from the TOMS and OMI instruments. The severity of the hole has been assessed using the minimum total ozone value from the October monthly mean (depth of the hole), the average size during the September-October period, and the ozone mass deficit. Ozone is mainly destroyed by halogen catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this presentation, we show the relationships of halogens and temperature to both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. We use two methods to estimate ozone hole recovery. First, we use projections of halogen levels combined with age-of-air estimates in a parametric model. Second, we use a coupled chemistry climate model to assess recovery. We find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. Furthermore, full recovery to 1980 levels will not occur until approximately 2068. We will also show some error estimates of these dates and the impact of climate change on the recovery.

  1. When will the Antarctic Ozone Hole Recover?

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Steve

    2006-01-01

    The Antarctic ozone hole develops each year and culminates by early Spring. Antarctic ozone values have been monitored since 1979 using satellite observations from the .TOMS instrument. The severity of the hole has been assessed from TOMS using the minimum total ozone value from the October monthly mean (depth of the hole) and by calculating the average size during the September-October period. Ozone is mainly destroyed by halogen catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this presentation, we show the relationships of halogens and temperature to, both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. Using projections of halogen levels combined with age-of-air estimates, we find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. The ozone hole will begin to show first signs of recovery in about 2023, and the hole will fully recover to pre-1980 levels in approximately 2070. This 2070 recovery is 20 years later than recent projections.

  2. Carbon isotope composition of Antarctic plants

    NASA Astrophysics Data System (ADS)

    Galimov, E. M.

    2000-05-01

    Carbon isotope compositions of Antarctic land plants are first reported. The most interesting feature is the isotope specificity of the species. For example Usnea antarctica from different locations shows relatively narrow range of the δ 13C-values from -22.44 to -21.29‰ (7 samples), Drepanocladus sp. from -24.86 to -23.49‰ (8 samples), and Andreaea depressincrvis from -23.87 to -23.23‰ (3 samples) etc. Usually, in inhabited lands and parts of the world with rich flora and developed soil, isotopic specificity of species is masked by variations of carbon isotope composition of CO 2. In Antarctic conditions influence of local sources of CO 2 on the isotope composition of CO 2 is appeared to be minimal. Therefore the δ 13C-variations inherent to individual plant physiology and biochemistry can be distinguished on the background of the stable level of the atmospheric CO 2 δ 13C-value. The latter is best to reflect the global state of the carbon cycle.

  3. CHAMP Magnetic Anomalies of the Antarctic Crust

    NASA Technical Reports Server (NTRS)

    Kim, Hyung Rae; Gaya-Pique, Luis R.; vonFrese, Ralph R. B.; Taylor, Patrick T.; Kim, Jeong Woo

    2003-01-01

    Regional magnetic signals of the crust are strongly masked by the core field and its secular variations components and hence difficult to isolate in the satellite measurements. In particular, the un-modeled effects of the strong auroral external fields and the complicated- behavior of the core field near the geomagnetic poles conspire to greatly reduce the crustal magnetic signal-to-noise ratio in the polar regions relative to the rest of the Earth. We can, however, use spectral correlation theory to filter the static lithospheric and core field components from the dynamic external field effects. To help isolate regional lithospheric from core field components, the correlations between CHAMP magnetic anomalies and the pseudo magnetic effects inferred from gravity-derived crustal thickness variations can also be exploited.. Employing these procedures, we processed the CHAMP magnetic observations for an improved magnetic anomaly map of the Antarctic crust. Relative to the much higher altitude Orsted and noisier Magsat observations, the CHAMP magnetic anomalies at 400 km altitude reveal new details on the effects of intracrustal magnetic features and crustal thickness variations of the Antarctic.

  4. A Standard Atmosphere of the Antarctic Plateau

    NASA Technical Reports Server (NTRS)

    Mahesh, Ashwin; Lubin, Dan

    2004-01-01

    Climate models often rely on standard atmospheres to represent various regions; these broadly capture the important physical and radiative characteristics of regional atmospheres, and become benchmarks for simulations by researchers. The high Antarctic plateau is a significant region of the earth for which such standard atmospheres are as yet unavailable. Moreover, representative profiles from atmospheres over other regions of the planet, including &om the northern high latitudes, are not comparable to the atmosphere over the Antarctic plateau, and are therefore only of limited value as substitutes in climate models. Using data from radiosondes, ozonesondes and satellites along with other observations from South Pole station, typical seasonal atmospheric profiles for the high plateau are compiled. Proper representations of rapidly changing ozone concentrations (during the ozone hole) and the effect of surface elevation on tropospheric temperatures are discussed. The differences between standard profiles developed here and the most similar standard atmosphere that already exists - namely, the Arctic Winter profile - suggest that these new profiles will be extremely useful to make accurate representations of the atmosphere over the high plateau.

  5. Quantitative characterization of the Antarctic ozone hole

    NASA Technical Reports Server (NTRS)

    Ito, T.; Sakoda, Y.; Matsubara, K.; Takao, T.; Akagi, K.; Watanabe, Y.; Shibata, S.; Naganuma, H.

    1994-01-01

    The long-term evolution of the Antarctic ozone hole is studied based on the TOMS data and the JMA data-set of stratospheric temperature in relation with the possible role of polar stratospheric clouds (PSC's). The effective mass of depleted ozone in the ozone hole at its annual mature stage reached a historical maximum of 55 Mt in 1991, 4.3 times larger than in 1981. The ozone depletion rate during 30 days before the mature ozone hole does not show any appreciable long-term trend but the interannual fluctuations do, ranging from 0.169 to 0.689 Mt/day with the average of 0.419 Mt/day for the period of 1979 - 1991. The depleted ozone mass has the highest correlation with the region below 195 K on the 30 mb surface in June, whereas the ozone depletion rate correlates most strongly with that in August. The present result strongly suggests that the long-term evolution of the mature ozone hole is caused both by the interannual change of the latitudinal coverage of the early PSC's, which may control the latitude and date of initiation of ozone decrease, and by that of the spatial coverage of the mature PSC's which may control the ozone depletion rate in the Antarctic spring.

  6. When Will the Antarctic Ozone Hole Recover?

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.

    2006-01-01

    The Antarctic ozone hole develops each year and culminates by early spring (late September - early October). Antarctic ozone values have been monitored since 1979 using satellite observations from the TOMS instrument. The severity of the hole has been assessed from TOMS using the minimum total ozone value from the October monthly mean (depth of the hole) and by calculating the average area coverage during this September-October period. Ozone is mainly destroyed by halogen (chlorine and bromine) catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this talk, I will show the relationships of halogens and temperature to both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. Using projections of halogen levels combined with age-of-air estimates, we find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. The ozone hole will begin to show first signs of recovery in about 2023, and the hole will fully recover to pre-1980 levels in approximately 2070. This 2070 recovery is 20 years later than recent projections. I will also discuss current assessments of mid-latitude ozone recovery.

  7. The tidal spectrum underneath Antarctic Ice Shelves

    NASA Astrophysics Data System (ADS)

    Pedley, M.; Paren, J. G.; Potter, J. R.

    1986-11-01

    A year-long tidal record has been obtained from beneath the George VI Ice Shelf, Antarctica. An unusual feature of the record is a significant response in tidal species 3 to 7. These harmonics are practically absent from records further north on the west coast of the Antarctic Peninsula but are present in all tidal height records from George VI Sound. A strong ter-diurnal signal also exists in the tidal currents under the ice shelf. Nonlinearity also occurs in the tidal motion of the Ronne and Ekström ice shelves but has not been reported from the Ross Ice Shelf. The tidal dynamics of several Antarctic ice shelves have therefore been modified by a region of strong nonlinear response to tidal forcing. If nonlinear tides in the semidiurnal band are present on the Ross Ice Shelf, they could account for difficulties in modeling the area's weak semidiurnal tides. An anelastic component in the deformation of the ice at the grounding line is tentatively proposed as the mechanism responsible. The positioning of recording pressure sensors in pairs on the seafloor and at the ice shelf base will allow this hypothesis to be tested and also provide a value for the power dissipated by tidally induced flexure at the grounding line.

  8. Drag coefficients for winter Antarctic pack ice

    NASA Technical Reports Server (NTRS)

    Wamser, Christian; Martinson, Douglas G.

    1993-01-01

    Air-ice and ice-water drag coefficients referenced to 10-m-height winds for winter Antarctic pack ice based on measurements made from R/V Polarstern during the Winter Weddell Sea Project, 1986 (WWSP-86), and from R/V Akademik Fedorov during the Winter Weddell Gyre Study, 1989 (WWGS-89), are presented. The optimal values of the air-ice drag coefficients, made from turbulent flux measurements, are (1.79 +/- 0.06) x 10 exp -3 for WWSP-86 and (1.45 +/- 0.09) x 10 exp -3 for WWGS-89. A single ice-water drag coefficient for both WWSP-86 and WWGS-89, estimated from periods of ice drift throught to represent free-drift conditions, is (1.13 +/- 0.26) x 10 exp -3, and the ice-water turning angle is 18 +/- 18 deg. It is suggested that for a typical Antarctic winter pack ice cover, the ice cover reduces the momentum flux from the atmosphere to the ocean by about 33 percent.

  9. Mass balance of the Antarctic ice sheet.

    PubMed

    Wingham, D J; Shepherd, A; Muir, A; Marshall, G J

    2006-07-15

    The Antarctic contribution to sea-level rise has long been uncertain. While regional variability in ice dynamics has been revealed, a picture of mass changes throughout the continental ice sheet is lacking. Here, we use satellite radar altimetry to measure the elevation change of 72% of the grounded ice sheet during the period 1992-2003. Depending on the density of the snow giving rise to the observed elevation fluctuations, the ice sheet mass trend falls in the range -5-+85Gtyr-1. We find that data from climate model reanalyses are not able to characterise the contemporary snowfall fluctuation with useful accuracy and our best estimate of the overall mass trend-growth of 27+/-29Gtyr-1-is based on an assessment of the expected snowfall variability. Mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic mass loss from West Antarctica. The result exacerbates the difficulty of explaining twentieth century sea-level rise. PMID:16782603

  10. Eukaryotes in Arctic and Antarctic cyanobacterial mats.

    PubMed

    Jungblut, Anne D; Vincent, Warwick F; Lovejoy, Connie

    2012-11-01

    Cyanobacterial mats are commonly found in freshwater ecosystems throughout the polar regions. Most mats are multilayered three-dimensional structures with the filamentous cyanobacteria embedded in a gel-like matrix. Although early descriptions mentioned the presence of larger organisms including metazoans living in the mats, there have been few studies specifically focused on the microbial eukaryotes, which are often small cells with few morphological features suitable for identification by microscopy. Here, we applied 18S rRNA gene clone library analysis to identify eukaryotes in cyanobacterial mat communities from both the Antarctic and the extreme High Arctic. We identified 39 ribotypes at the level of 99% sequence similarity. These consisted of taxa within algal and other protist groups including Chlorophyceae, Prasinophyceae, Ulvophyceae, Trebouxiophyceae, Bacillariophyceae, Chrysophyceae, Ciliophora, and Cercozoa. Fungi were also recovered, as were 21 metazoan ribotypes. The eukaryotic taxa appeared habitat-specific with little overlap between lake, pond, and ice shelf communities. Some ribotypes were common to both Arctic and Antarctic mats, suggesting global dispersal of these taxa and similarity in the environmental filters acting on protist communities. Many of these eukaryotic taxa likely benefit from protected, nutrient-rich microhabitats within the cyanobacterial mat environment. PMID:22630054

  11. 9 CFR 95.30 - Restrictions on entry of products and byproducts of poultry, game birds, or other birds from...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... byproducts of poultry, game birds, or other birds from regions where highly pathogenic avian influenza (HPAI... THE UNITED STATES § 95.30 Restrictions on entry of products and byproducts of poultry, game birds, or...) Products or byproducts, including feathers, birds' nests, and bird trophies, of poultry, game birds,...

  12. 9 CFR 95.30 - Restrictions on entry of products and byproducts of poultry, game birds, or other birds from...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... byproducts of poultry, game birds, or other birds from regions where highly pathogenic avian influenza (HPAI... THE UNITED STATES § 95.30 Restrictions on entry of products and byproducts of poultry, game birds, or...) Products or byproducts, including feathers, birds' nests, and bird trophies, of poultry, game birds,...

  13. Distribution and abundance of Antarctic krill (Euphausia superba) along the Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Siegel, Volker; Reiss, Christian S.; Dietrich, Kimberly S.; Haraldsson, Matilda; Rohardt, Gerhard

    2013-07-01

    Net-based data on the abundance, distribution, and demographic patterns of Antarctic krill are quantified from a contemporaneous two ship survey of the Antarctic Peninsula during austral summer 2011. Two survey areas were sampled focussed on Marguerite Bay in the south, and the tip of the Antarctic Peninsula in the north. Data from 177 stations showed that the highest concentrations of krill were found in the southern sampling area. Differences between areas were associated with a few large catches of one year old krill found in anomalously warm and productive waters in Marguerite Bay, and small krill catches in the less-productive, offshore waters in the north. Estimated krill density across the survey area was 3.4 krill m-2, and was low compared to the long-term average of 45 krill m-2 for the Elephant Island area. Overall recruitment between the two survey regions was similar, but per capita recruitment was about 60% lower than historical mean recruitment levels measured at Elephant Island since the late 1970s. Demographic patterns showed small krill concentrated near the coast, and large krill concentrated offshore on the shelf and slope all along the survey area. The offshore distribution of adult krill was delineated by the warm (˜1 °C), low salinity (33.8) water at 30 m, suggesting that most krill were present shoreward of the southern boundary of Antarctic Circumpolar Current Front. Distributions of larvae indicated that three hotspot areas were important for the production of krill: slope areas outside Marguerite Bay and north of the South Shetland Islands, and near the coast around Antarctic Sound. Successful spawning, as inferred from larval abundance, was roughly coincident with the shelf break and not with inshore waters. Given the rapid changes in climate along the Antarctic Peninsula and the lower per capita recruitment observed in recent years, studies comparing and contrasting production, growth, and recruitment across the Peninsula will be

  14. Antarctic Crustal Thickness from Gravity Inversion

    NASA Astrophysics Data System (ADS)

    Vaughan, A. P.; Kusznir, N. J.; Ferraccioli, F.; Jordan, T. A.

    2013-12-01

    Using gravity anomaly inversion, we have produced the first comprehensive regional maps of crustal thickness and oceanic lithosphere distribution for Antarctica and the Southern Ocean. We determine Moho depth, crustal basement thickness, continental lithosphere thinning (1-1/β) and ocean-continent transition location using a 3D spectral domain gravity inversion method, which incorporates a lithosphere thermal gravity anomaly correction. The continental lithosphere thinning distribution, used to define the initial thermal model temperature perturbation is derived from the gravity inversion and uses no a priori isochron information; as a consequence the gravity inversion method provides a prediction of ocean-continent transition location, which is independent of ocean isochron information. The gravity anomaly contribution from ice thickness is included in the gravity inversion, as is the contribution from sediments which assumes a compaction controlled sediment density increase with depth. Data used in the gravity inversion are elevation and bathymetry, free-air gravity anomaly, the most recent Bedmap2 ice thickness and bedrock topography compilation south of 60 degrees south (Fretwell et al., 2013) and relatively sparse constraints on sediment thickness. Our gravity inversion study predicts thick crust (> 45 km) under interior East Antarctica penetrated by narrow continental rifts that feature relatively thinner crust. The East Antarctic Rift System (EARS) is a major Permian to Cretaceous age rift system that appears to extend from the continental margin at the Lambert Rift to the South Pole region, a distance of 2500 km. This is comparable in scale to the well-studied East African rift system. Intermediate crustal thickness with an inferred linear rift fabric is predicted under Coates Land. An extensive region of either thick oceanic crust or highly thinned continental crust is predicted offshore Oates Land and north Victoria Land, and also off West Antarctica

  15. Urban Bird Feeding: Connecting People with Nature

    PubMed Central

    Gaston, Kevin J.

    2016-01-01

    At a time of unprecedented biodiversity loss, researchers are increasingly recognizing the broad range of benefits provided to humankind by nature. However, as people live more urbanized lifestyles there is a progressive disengagement with the natural world that diminishes these benefits and discourages positive environmental behaviour. The provision of food for garden birds is an increasing global phenomenon, and provides a readily accessible way for people to counter this trend. Yet despite its popularity, quite why people feed birds remains poorly understood. We explore three loosely defined motivations behind bird feeding: that it provides psychological benefits, is due to a concern about bird welfare, and/or is due to a more general orientation towards nature. We quantitatively surveyed households from urban towns in southern England to explore attitudes and actions towards garden bird feeding. Each household scored three Likert statements relating to each of the three motivations. We found that people who fed birds regularly felt more relaxed and connected to nature when they watched garden birds, and perceived that bird feeding is beneficial for bird welfare while investing time in minimising associated risks. Finally, feeding birds may be an expression of a wider orientation towards nature. Overall, we found that the feelings of being relaxed and connected to nature were the strongest drivers. As urban expansion continues both to threaten species conservation and to change peoples’ relationship with the natural world, feeding birds may provide an important tool for engaging people with nature to the benefit of both people and conservation. PMID:27427988

  16. Mapping Global Diversity Patterns for Migratory Birds

    PubMed Central

    Somveille, Marius; Manica, Andrea; Butchart, Stuart H. M.; Rodrigues, Ana S. L.

    2013-01-01

    Nearly one in five bird species has separate breeding and overwintering distributions, and the regular migrations of these species cause a substantial seasonal redistribution of avian diversity across the world. However, despite its ecological importance, bird migration has been largely ignored in studies of global avian biodiversity, with few studies having addressed it from a macroecological perspective. Here, we analyse a dataset on the global distribution of the world’s birds in order to examine global spatial patterns in the diversity of migratory species, including: the seasonal variation in overall species diversity due to migration; the contribution of migratory birds to local bird diversity; and the distribution of narrow-range and threatened migratory birds. Our analyses reveal a striking asymmetry between the Northern and Southern hemispheres, evident in all of the patterns investigated. The highest migratory bird diversity was found in the Northern Hemisphere, with high inter-continental turnover in species composition between breeding and non-breeding seasons, and extensive regions (at high latitudes) where migratory birds constitute the majority of the local avifauna. Threatened migratory birds are concentrated mainly in Central and Southern Asia, whereas narrow-range migratory species are mainly found in Central America, the Himalayas and Patagonia. Overall, global patterns in the diversity of migratory birds indicate that bird migration is mainly a Northern Hemisphere phenomenon. The asymmetry between the Northern and Southern hemispheres could not have easily been predicted from the combined results of regional scale studies, highlighting the importance of a global perspective. PMID:23951037

  17. Mapping global diversity patterns for migratory birds.

    PubMed

    Somveille, Marius; Manica, Andrea; Butchart, Stuart H M; Rodrigues, Ana S L

    2013-01-01

    Nearly one in five bird species has separate breeding and overwintering distributions, and the regular migrations of these species cause a substantial seasonal redistribution of avian diversity across the world. However, despite its ecological importance, bird migration has been largely ignored in studies of global avian biodiversity, with few studies having addressed it from a macroecological perspective. Here, we analyse a dataset on the global distribution of the world's birds in order to examine global spatial patterns in the diversity of migratory species, including: the seasonal variation in overall species diversity due to migration; the contribution of migratory birds to local bird diversity; and the distribution of narrow-range and threatened migratory birds. Our analyses reveal a striking asymmetry between the Northern and Southern hemispheres, evident in all of the patterns investigated. The highest migratory bird diversity was found in the Northern Hemisphere, with high inter-continental turnover in species composition between breeding and non-breeding seasons, and extensive regions (at high latitudes) where migratory birds constitute the majority of the local avifauna. Threatened migratory birds are concentrated mainly in Central and Southern Asia, whereas narrow-range migratory species are mainly found in Central America, the Himalayas and Patagonia. Overall, global patterns in the diversity of migratory birds indicate that bird migration is mainly a Northern Hemisphere phenomenon. The asymmetry between the Northern and Southern hemispheres could not have easily been predicted from the combined results of regional scale studies, highlighting the importance of a global perspective. PMID:23951037

  18. Urban Bird Feeding: Connecting People with Nature.

    PubMed

    Cox, Daniel T C; Gaston, Kevin J

    2016-01-01

    At a time of unprecedented biodiversity loss, researchers are increasingly recognizing the broad range of benefits provided to humankind by nature. However, as people live more urbanized lifestyles there is a progressive disengagement with the natural world that diminishes these benefits and discourages positive environmental behaviour. The provision of food for garden birds is an increasing global phenomenon, and provides a readily accessible way for people to counter this trend. Yet despite its popularity, quite why people feed birds remains poorly understood. We explore three loosely defined motivations behind bird feeding: that it provides psychological benefits, is due to a concern about bird welfare, and/or is due to a more general orientation towards nature. We quantitatively surveyed households from urban towns in southern England to explore attitudes and actions towards garden bird feeding. Each household scored three Likert statements relating to each of the three motivations. We found that people who fed birds regularly felt more relaxed and connected to nature when they watched garden birds, and perceived that bird feeding is beneficial for bird welfare while investing time in minimising associated risks. Finally, feeding birds may be an expression of a wider orientation towards nature. Overall, we found that the feelings of being relaxed and connected to nature were the strongest drivers. As urban expansion continues both to threaten species conservation and to change peoples' relationship with the natural world, feeding birds may provide an important tool for engaging people with nature to the benefit of both people and conservation. PMID:27427988

  19. Russian deep-sea investigations of Antarctic fauna

    NASA Astrophysics Data System (ADS)

    Malyutina, Marina

    2004-07-01

    A review of the Russian deep-sea investigation of Antarctic fauna beginning from the first scientific collection of Soviet whaling fleet expeditions 1946-1952 is presented. The paper deals with the following expeditions, their main tasks and results. These expeditions include three cruises of research vessel (R.V.) Ob in the Indian sector of the Antarctic and in the Southern Pacific (1955-1958); 11 cruises of the R.V. Akademik Kurchatov in the southern Atlantic (November-December 1971); 16 cruises of the R.V. Dmitriy Mendeleev in the Australia-New Zealand area and adjacent water of the Antarctic (December 1975-March 1976); 43 cruises of the R.V. Akademik Kurchatov in the southern Atlantic (October 1985-February 1986); and 43 cruises of the R.V. Dmitriy Mendeleev in the Atlantic sector of the South Ocean (January-May 1989). A list of the main publications on the benthic taxa collected during these expeditions with data of their distribution is presented. The results of Russian explorations of the Antarctic fauna are presented as theoretical conclusions in the following topics: (1) Vertical zonation in the distribution of the Antarctic deep-sea fauna; (2) Biogeographic division of the abyssal and hadal zones; (3) Origin of the Antarctic deep-sea fauna; (4) Distributional pathways of the Antarctic abyssal fauna through the World Ocean.

  20. Microbial biomass and basal respiration in Sub-Antarctic and Antarctic soils in the areas of some Russian polar stations

    NASA Astrophysics Data System (ADS)

    Abakumov, E.; Mukhametova, N.

    2014-03-01

    Antarctica is the unique place for pedological investigations. Soils of Antarctica have been studied intensively during the last century. Antarctic logistic provides the possibility to scientists access the terrestrial landscapes mainly in the places of polar stations. That is why the main and most detailed pedological investigations were conducted in Mc Murdo Valleys, Transantarctic Mountains, South Shetland Islands, Larsemann hills and Schirmacher Oasis. Investigations were conducted during the 53rd and 55th Russian Antarctic expeditions on the base of soil pits and samples collected in Sub-Antarctic and Antarctic regions. Soils of diverse Antarctic landscapes were studied with aim to assess the microbial biomass level, basal respiration rates and metabolic activity of microbial communities. The investigation conducted shows that soils of Antarctic are quite different in profile organization and carbon content. In general, Sub-Antarctic soils are characterized by more developed humus (sod) organo-mineral horizons as well as the upper organic layer. The most developed organic layers were revealed in peat soils of King-George Island, where its thickness reach even 80 cm. These soils as well as soils under guano are characterized by the highest amount of total organic carbon (TOC) 7.22-33.70%. Coastal and continental soils of Antarctic are presented by less developed Leptosols, Gleysols, Regolith and rare Ornhitosol with TOC levels about 0.37-4.67%. The metabolic ratios and basal respiration were higher in Sub-Antarctic soils than in Antarctic ones which can be interpreted as result of higher amounts of fresh organic remnants in organic and organo-mineral horizons. Also the soils of King-George island have higher portion of microbial biomass (max 1.54 mg g-1) than coastal (max 0.26 mg g-1) and continental (max 0.22 mg g-1) Antarctic soils. Sub-Antarctic soils mainly differ from Antarctic ones in increased organic layers thickness and total organic carbon content

  1. The impacts of local human activities on the Antarctic environment

    NASA Astrophysics Data System (ADS)

    Tin, T.; Fleming, Z. L.; Hughes, K. A.; Ainley, D. G.; Convey, P.; Moreno, C. A.; Pfeiffer, S.; Scott, J.; Snape, I.

    2009-04-01

    An overview of a recently published review of the scientific literature from the past decade on the impacts of human activities on the Antarctic environment is presented. An assessment of the cumulative effects of scientists and accompanying base construction, tourists and fishery activities in Antarctica is timely given a decade since the Protocol on Environmental Protection to the Antarctic Treaty came into force in 1998 and the increasing attention given to and human presence in Antarctica during this 2007-2009 IPY. A range of impacts has been identified at a variety of spatial and temporal scales. Chemical contamination and sewage disposal on the continent have been found to be long-lived, with contemporary sewage management practices at many coastal stations insufficient to prevent local contamination. Human activities, particularly construction and transport, have affected Antarctic flora and fauna and a small number of non-indigenous plant and animal species has become established on some of the Antarctic Peninsula and sub Antarctic islands. There is little indication of recovery of overexploited fish stocks, and ramifications of fishing activity on bycatch species and the ecosystem could also be far-reaching. The Antarctic Treaty System and its instruments, in particular the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) and the Environmental Protocol, provide a framework within which management of human activities take place. In order to ensure comprehensive protection of the Antarctic environment, including its intrinsic, wilderness and scientific values in the face of the continuing expansion of human activities in Antarctica, a more effective implementation of a wide range of measures is essential. These include effective environmental impact assessments, long-term monitoring, mitigation measures for non-indigenous species, ecosystem-based management of living resources, and increased regulation of National Antarctic

  2. Stable recombination hotspots in birds

    PubMed Central

    Singhal, Sonal; Leffler, Ellen M.; Sannareddy, Keerthi; Turner, Isaac; Venn, Oliver; Hooper, Daniel M.; Strand, Alva I.; Li, Qiye; Raney, Brian; Balakrishnan, Christopher N.; Griffith, Simon C.; McVean, Gil; Przeworski, Molly

    2016-01-01

    The DNA-binding protein PRDM9 has a critical role in specifying meiotic recombination hotspots in mice and apes, but appears to be absent from other vertebrate species, including birds. To study the evolution and determinants of recombination in species lacking PRDM9, we inferred fine-scale genetic maps from population resequencing data for two bird species, the zebra finch Taeniopygia guttata and the long-tailed finch Poephila acuticauda. We find that both species have hotspots, which are enriched near functional genomic elements. Unlike in mice and apes, the two species share most hotspots, with conservation seemingly extending over tens of millions of years. These observations suggest that in the absence of PRDM9, recombination targets functional features that both enable access to the genome and constrain its evolution. PMID:26586757

  3. Stable recombination hotspots in birds.

    PubMed

    Singhal, Sonal; Leffler, Ellen M; Sannareddy, Keerthi; Turner, Isaac; Venn, Oliver; Hooper, Daniel M; Strand, Alva I; Li, Qiye; Raney, Brian; Balakrishnan, Christopher N; Griffith, Simon C; McVean, Gil; Przeworski, Molly

    2015-11-20

    The DNA-binding protein PRDM9 has a critical role in specifying meiotic recombination hotspots in mice and apes, but it appears to be absent from other vertebrate species, including birds. To study the evolution and determinants of recombination in species lacking the gene that encodes PRDM9, we inferred fine-scale genetic maps from population resequencing data for two bird species: the zebra finch, Taeniopygia guttata, and the long-tailed finch, Poephila acuticauda. We found that both species have recombination hotspots, which are enriched near functional genomic elements. Unlike in mice and apes, most hotspots are shared between the two species, and their conservation seems to extend over tens of millions of years. These observations suggest that in the absence of PRDM9, recombination targets functional features that both enable access to the genome and constrain its evolution. PMID:26586757

  4. Terrestrial ages of Antarctic meteorites: Implications for concentration mechanisms

    NASA Technical Reports Server (NTRS)

    Schultz, L.

    1986-01-01

    Antarctic meteorites differ from meteorites fallen in other places in their mean terrestrial ages. Boeckl estimated the terrestrial half-life for the disintegration of stone meteorites by weathering under the climatic conditions of the Western United States to be about 3600 years. Antarctic meteorites, however, have terrestrial ages up to 70000 years, indicating larger weathering half-lives. The terrestrial ages of meteorites are determined by their concentration of cosmic-ray-produced radionuclides with suitable half-lives (C-14, Al-26, and Cl-36). These radionuclides have yielded reliable ages for the Antarctic meteorites. The distribution of terrestrial ages of Allan Hills and Yamato meteorites are examined.

  5. Niche-dependent genetic diversity in Antarctic metaviromes

    PubMed Central

    Zablocki, Olivier; van Zyl, Lonnie; Adriaenssens, Evelien M; Rubagotti, Enrico; Tuffin, Marla; Cary, Stephen C; Cowan, Don

    2014-01-01

    The metaviromes from 2 different Antarctic terrestrial soil niches have been analyzed. Both hypoliths (microbial assemblages beneath transluscent rocks) and surrounding open soils showed a high level diversity of tailed phages, viruses of algae and amoeba, and virophage sequences. Comparisons of other global metaviromes with the Antarctic libraries showed a niche-dependent clustering pattern, unrelated to the geographical origin of a given metavirome. Within the Antarctic open soil metavirome, a putative circularly permuted, ∼42kb dsDNA virus genome was annotated, showing features of a temperate phage possessing a variety of conserved protein domains with no significant taxonomic affiliations in current databases. PMID:26458512

  6. Measurements of Cl-36 in Antarctic meteorites and Antarctic ice using a Van de Graaff accelerator

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Arnold, J. R.; Finkel, R. C.; Elmore, D.; Ferraro, R. D.; Gove, H. E.; Beukens, R. P.; Chang, K. H.; Kilius, L. R.

    1979-01-01

    The paper presents measurements of cosmic-ray produced (Cl-36) in Antarctic meteorites and ice using a Van de Graaff accelerator as an ultrasensitive mass spectrometer. Results from this ion counting technique are used to support a two-stage irradiation model for the Yamato-7301 and Allan Hills-76008 meteorites and to show a long terrestrial age for Allan Hills-77002. Yamato-7304 has a terrestrial age of less than 0.1 m.y., and the (Cl-36) content of the Antarctic ice sample from the Yamato mountain is consistent with levels expected in currently depositing snow implying that the age of the ice cap at this site is less than on (Cl-36) half-life.

  7. Critical Care of Pet Birds.

    PubMed

    Jenkins, Jeffrey Rowe

    2016-05-01

    Successful care of the critical pet bird patient is dependent on preparation and planning and begins with the veterinarian and hospital staff. An understanding of avian physiology and pathophysiology is key. Physical preparation of the hospital or clinic includes proper equipment and understanding of the procedures necessary to provide therapeutic and supportive care to the avian patient. An overview of patient intake and assessment, intensive care environment, and fluid therapy is included. PMID:27131161

  8. Energetics and longevity in birds

    PubMed Central

    Furness, L. J.

    2008-01-01

    The links between energy expenditure and ageing are different at different levels of enquiry. When studies have examined the relationships between different species within a given class the association is generally negative—animals with greater metabolism per gram of tissue live shorter lives. Within species, or between classes (e.g. between birds and mammals) the association is the opposite—animals with higher metabolic rates live longer. We have previously shown in mammals that the negative association between lifespan and metabolic rate is in fact an artefact of using resting rather than daily energy expenditure, and of failing to adequately take into account the confounding effects of body size and the lack of phylogenetic independence of species data. When these factors are accounted for, across species of mammals, the ones with higher metabolism also have the largest lifetime expenditures of energy—consistent with the inter-class and intra-specific data. A previous analysis in birds did not yield the same pattern, but this may have been due to a lack of sufficient power in the analysis. Here we present an analysis of a much enlarged data set (>300 species) for metabolic and longevity traits in birds. These data show very similar patterns to those in mammals. Larger individuals have longer lives and lower per-gram resting and daily energy expenditures, hence there is a strong negative relationship between longevity and mass-specific metabolism. This relationship disappears when the confounding effects of body mass and phylogeny are accounted for. Across species of birds, lifetime expenditure of energy per gram of tissue based on both daily and resting energy expenditure is positively related to metabolic intensity, mirroring these statistical relationships in mammals and synergising with the positive associations of metabolism with lifespan within species and between vertebrate classes. PMID:19424858

  9. F-8 Iron Bird Cockpit

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The F-8 DFBW (Digital-Fly-By-Wire) simulator used an 'Iron-Bird' for its cockpit. It was used from 1971 to 1986. The F-8 DFBW simulator was used in the development, testing, and validation of an all digital flight-control system installed in the F-8 aircraft that replaced the normal mechanical/hydraulic controls. Many military and commercial aircraft have digital flight control systems based on the technologies developed at NASA Dryden.

  10. Antarctic meteorite newsletter. Volume 4: Number 1, February 1981: Antarctic meteorite descriptions, 1976, 1977, 1978, 1979

    NASA Technical Reports Server (NTRS)

    Stone, R.; Schwarz, C. M.; King, T. V. V.; Mason, B.; Bogard, D. D.; Gabel, E. M.

    1981-01-01

    This issue of the Newsletter is essentially a catalog of all antarctic meteorites in the collections of the Johnson Space Center Curation Facility and the Smithsonian except for 288 pebbles now being classed. It includes listings of all previously distributed data sheets plus a number of new ones for 1979. Indexes of samples include meteorite name/number, classification, and weathering category. Separate indexes list type 3 and 4 chondrites, all irons, all achondrites, and all carbonaceous chondrites.

  11. Different adaptations of Chinese winter-over expeditioners during prolonged Antarctic and sub-Antarctic residence

    NASA Astrophysics Data System (ADS)

    Chen, Nan; Wu, Quan; Li, Hao; Zhang, Tao; Xu, Chengli

    2016-05-01

    Prolonged residence in Antarctica is characterized by exposure to isolated, confined, and extreme (ICE) environment. Winter-over expeditioners at research stations often exhibit a complex of psychophysiological symptoms, which varied by stations and sociocultural backgrounds. To understand the different patterns of psychophysiological responses provoked by environmental stress, we conducted a longitudinal assessment of mood and endocrine function in two groups of Chinese expeditioners who were deployed to sub-Antarctic (Great Wall Station, 62°S, N = 12) and Antarctic (Zhongshan Station, 66°S, N = 16) from December 2003 to 2005. Measures of mood, thyroid function, the levels of plasma catecholamine, and circulating interleukins were obtained at departure from China, mid-winter (Antarctica), end of winter (Antarctica), and return to China, respectively. The Zhongshan Station crew experienced significant increases in fatigue, anger, tension, confusion, and decrease in free thyroxine (FT4), norepinephrine (NE), and epinephrine (E) during the winter, increase in thyrotropin (TSH) and total triiodothyronine (TT3) when returning, whereas their counterparts at Great Wall Station only experienced increased TT3 after deployment. Moreover, compared with the Great Wall Station crew, the Zhongshan Station crew exhibited greater increase in anger, greater decrease in FT4, total thyroxine (TT4), NE and E over the winter, and greater increase in TSH when returning. Chinese expeditioners who lived and worked at the Antarctic station and the sub-Antarctic station for over a year showed different change patterns in mood and endocrine hormones. Negative mood and endocrine dysfunction were positively associated with the severity of environment. The study is a supplement to scientific knowledge on psychophysiological variation under ICE environment, which has certain applied value for the development of preventive countermeasures or interventions.

  12. Different adaptations of Chinese winter-over expeditioners during prolonged Antarctic and sub-Antarctic residence.

    PubMed

    Chen, Nan; Wu, Quan; Li, Hao; Zhang, Tao; Xu, Chengli

    2016-05-01

    Prolonged residence in Antarctica is characterized by exposure to isolated, confined, and extreme (ICE) environment. Winter-over expeditioners at research stations often exhibit a complex of psychophysiological symptoms, which varied by stations and sociocultural backgrounds. To understand the different patterns of psychophysiological responses provoked by environmental stress, we conducted a longitudinal assessment of mood and endocrine function in two groups of Chinese expeditioners who were deployed to sub-Antarctic (Great Wall Station, 62°S, N = 12) and Antarctic (Zhongshan Station, 66°S, N = 16) from December 2003 to 2005. Measures of mood, thyroid function, the levels of plasma catecholamine, and circulating interleukins were obtained at departure from China, mid-winter (Antarctica), end of winter (Antarctica), and return to China, respectively. The Zhongshan Station crew experienced significant increases in fatigue, anger, tension, confusion, and decrease in free thyroxine (FT4), norepinephrine (NE), and epinephrine (E) during the winter, increase in thyrotropin (TSH) and total triiodothyronine (TT3) when returning, whereas their counterparts at Great Wall Station only experienced increased TT3 after deployment. Moreover, compared with the Great Wall Station crew, the Zhongshan Station crew exhibited greater increase in anger, greater decrease in FT4, total thyroxine (TT4), NE and E over the winter, and greater increase in TSH when returning. Chinese expeditioners who lived and worked at the Antarctic station and the sub-Antarctic station for over a year showed different change patterns in mood and endocrine hormones. Negative mood and endocrine dysfunction were positively associated with the severity of environment. The study is a supplement to scientific knowledge on psychophysiological variation under ICE environment, which has certain applied value for the development of preventive countermeasures or interventions. PMID:26842369

  13. Iron in East Antarctic snow: Implications for atmospheric iron deposition and algal production in Antarctic waters

    NASA Astrophysics Data System (ADS)

    Edwards, Ross; Sedwick, Peter

    To evaluate the deposition and solubility of aerosol iron in the Antarctic seasonal sea ice zone (SSIZ), iron was measured in snow samples collected from three areas in the SSIZ (Prydz Bay, Dumont d'Urville Sea and Ross Sea) and one continental area (Princess Elizabeth Land) of East Antarctica. Concentrations of total-dissolvable iron (that soluble at pH ˜2) ranged from 20-2950 pg g-1, with the lowest concentrations measured in snow from the Dumont d'Urville Sea. Using estimates of snow accumulation rates, we calculate atmospheric iron deposition fluxes of 0.017-0.11 mg m-2 yr-1 (0.30-2.0 µmol m-2 yr-1), which are generally lower than previously published estimates. Measurements of iron in filtered meltwaters of snow samples from Prydz Bay and Princess Elizabeth Land suggest that ˜10-90% of the total atmospheric iron is readily soluble. Assuming our results to be broadly representative of atmospheric deposition over seasonally ice-covered, high-nutrient Antarctic waters, we use our mean estimates of atmospheric iron deposition (1.1 µmol m-2 yr-1) and solubility (32%) to calculate that atmospheric iron potentially supports annual phytoplankton production of 1.1 × 1012 mole C in the Antarctic SSIZ, which is less than 5% of the estimated total annual primary production in this ocean region.

  14. Tropical pacing of Antarctic sea ice increase

    NASA Astrophysics Data System (ADS)

    Schneider, D. P.

    2015-12-01

    One reason why coupled climate model simulations generally do not reproduce the observed increase in Antarctic sea ice extent may be that their internally generated climate variability does not sync with the observed phases of phenomena like the Pacific Decadal Oscillation (PDO) and ENSO. For example, it is unlikely for a free-running coupled model simulation to capture the shift of the PDO from its positive to negative phase during 1998, and the subsequent ~15 year duration of the negative PDO phase. In previously presented work based on atmospheric models forced by observed tropical SSTs and stratospheric ozone, we demonstrated that tropical variability is key to explaining the wind trends over the Southern Ocean during the past ~35 years, particularly in the Ross, Amundsen and Bellingshausen Seas, the regions of the largest trends in sea ice extent and ice season duration. Here, we extend this idea to coupled model simulations with the Community Earth System Model (CESM) in which the evolution of SST anomalies in the central and eastern tropical Pacific is constrained to match the observations. This ensemble of 10 "tropical pacemaker" simulations shows a more realistic evolution of Antarctic sea ice anomalies than does its unconstrained counterpart, the CESM Large Ensemble (both sets of runs include stratospheric ozone depletion and other time-dependent radiative forcings). In particular, the pacemaker runs show that increased sea ice in the eastern Ross Sea is associated with a deeper Amundsen Sea Low (ASL) and stronger westerlies over the south Pacific. These circulation patterns in turn are linked with the negative phase of the PDO, characterized by negative SST anomalies in the central and eastern Pacific. The timing of tropical decadal variability with respect to ozone depletion further suggests a strong role for tropical variability in the recent acceleration of the Antarctic sea ice trend, as ozone depletion stabilized by late 1990s, prior to the most

  15. Biomarkers and Microbial Fossils In Antarctic Rocks

    NASA Astrophysics Data System (ADS)

    Wierzchos, J.; Ascaso, C.

    Lithobiontic microbial communities living within Antarctic rocks are an example of survival in an extremely cold and dry environment. Any unfavourable change in ex- ternal conditions can result in the death and disappearance of microscopic organisms, and this may be followed by the appearance of trace biomarkers and microbial fossils. The extinction of these microorganisms in some zones of the Ross Desert, probably provoked by the hostile environment, might be considered a good terrestrial analogue of the first stage of the disappearance of possible life on early Mars. Granite samples from maritime Antarctica (Granite Harbour) and sandstone rocks from the continental Ross Desert were collected with the aim of searching for biomarkers and microbial fossils at the microscopic level of observation. To this end, a novel in situ applica- tion of scanning electron microscopy with backscattered electron imaging was com- bined with the simultaneous use of X-ray energy dispersive spectroscopy techniques. Our findings confirm the existence of inorganic biomarkers in the form of physico- chemically bioweathered minerals within the granitic rocks. The presence of Fe-rich diagenetic minerals, such as iron hydroxide nanocrystals and biogenic clays around chasmoendolithic hyphae and bacterial cells was also observed. Others biomarkers, including inorganic deposits such as calcium oxalates and silica accumulations, are clear signs of endolithic microorganism activity. The interior of the sandstone rocks (Ross Desert, Mt. Fleming) reveal the presence of microbial fossils of algae and other endolithic microorganisms. These microbial fossils, detected for the first time within Antarctic rocks, contain well preserved and morphologically distinguishable relics of ultrastructural cytoplasm elements, such as cell walls, chloroplast membranes, and oc- casionally, pyrenoids and traces of organic matter. These structures are similar to those observed in live cells also found in Antarctic

  16. Factors influencing phototaxis in nocturnal migrating birds.

    PubMed

    Zhao, Xuebing; Chen, Mingyan; Wu, Zhaolu; Wang, Zijiang

    2014-12-01

    Many migratory bird species fly during the night (nocturnal migrants) and have been shown to display some phototaxis to artificial light. During 2006 to 2009, we investigated phototaxis in nocturnal migrants at Jinshan Yakou in Xinping County (N23°56', E101°30'; 2400 m above sea-level), and at the Niaowang Mountain in Funing County (N23°30', E105°35'; 1400 m above sea-level), both in the Yunnan Province of Southwest China. A total of 5069 birds, representing 129 species, were captured by mist-netting and artificial light. The extent of phototaxis effect on bird migration was examined during all four seasons, three phases of the moon, and under two weather conditions (mist and wind). Data were statistically analyzed to determine the extent to which these factors may impact phototaxis of nocturnal migrants. The results point to phototaxis in birds migrating in the spring and autumn, especially in the autumn. Furthermore, migrating birds were more readily attracted to artificial lights during nights with little moonlight, mist, and a headwind. Regardless of the initial orientation in which birds flew, either following the wind or against the wind, birds would always fly against the wind when flying towards the light. This study broadens our understanding of the nocturnal bird migration, potentially resulting in improved bird ringing practices, increased awareness, and better policies regarding bird protection. PMID:25483789

  17. Paleoclimate perspectives on Antarctic ice sheet sensitivity

    NASA Astrophysics Data System (ADS)

    Naish, Timothy

    2015-04-01

    Near- and long-term future projections of global mean sea level rise (SLR) are hampered by a lack of understanding of the potential dynamic contribution of the polar ice sheets, and in particular the Antarctic ice sheets. With the completion of the Intergovernmental Panel on Climate Change's Assessment Report a major challenge continues to be placing an upper bound in sea-level projections for 2100 and beyond. The so-called "deterministic" approach which sums observed- and model-projected trends in the known contributions (e.g. ice sheet and glacier surface mass balance, ocean thermal expansion and ground water storage changes) implies a "likely" upper bound of +100cm by 2080-2100. The "semi-empirical" approach which scales past observed sea-level change to mean surface temperature, and uses this relationship to scale future temperature scenarios, predicts a significantly higher upper bound of up to ~2m by 2100. The discrepancy between the two approaches may in part reflect the poorly understood contribution of ice dynamics - that is the rate of flow of ice sheets into the ocean. An ensemble of Antarctic ice sheet models produces highly divergent results for future sea-level projections, primarily because of uncertainties around the mass changes in the East Antarctic Ice Sheet with some models showing increased precipitation driving a positive mass balance overall, even with loss of the marine-based West Antarctic Ice Sheet (WAIS). Current best estimates suggest a 10-20cm dynamic ice sheet contribution by 2100 to global SLR. Of concern is that marine based ice sheets are highly sensitive to increases in ocean temperature at their margins and rapid disintegration may ensue if the ice sheets grounding lines retreat into deep sub-glacial basins. Recent studies show the highest rates of ice sheet thinning and retreat are occurring at locations around the WAIS where the surface ocean has warmed, and that some WAIS loss may now be irreversible. Geological records allow

  18. Antarctic surface temperature and pressure data

    SciTech Connect

    Jones, P.D.; Limbert, D.W.S.; Boden, T.A. . Climatic Research Unit; British Antarctic Survey, Cambridge; Oak Ridge National Lab., TN )

    1989-09-01

    This document presents monthly mean surface temperature and pressure data from 30 Antarctic stations. These data were assembled primarily from World Weather Records volumes for 1951--1960 and 1961--1979 and from Monthly Climatic Data for the World records since 1961. The periods of record vary by station. The earliest data are from 1903, and the most recent data are from 1988. All the assembled data were assessed for quality and for long-term homogeneity through the use of interstation comparison techniques. These data are available free of charge as a numeric data package (NDP) from the Carbon Dioxide Information Analysis Center. The NDP consists of this document and a magnetic tape containing machine-readable data files. This document provides tabular listings of the temperature and pressure data, describes how the data were processed, defines limitations and restrictions of the data, and provides reprints of pertinent literature. 25 refs., 3 figs., 11 tabs.

  19. Antarctic Meteorite Newsletter, Volume 29, Number 1

    NASA Technical Reports Server (NTRS)

    Satterwhite, Cecilia (Editor); Righter, Kevin (Editor)

    2006-01-01

    This newsletter contains classifications for 597 new meteorites from the 2003 and 2004 ANtarctic Search for METeorites (ANSMET) seasons. They include samples from the Cumulus Hills, Dominion Range, Grosvenor Mountains, LaPaz Icefield, MacAlpine Hills, and the Miller Range. Macroscopic and petrographic descriptions are given for 25 of the new meteorites: 1 acapulcoite/Iodranite, 1 howardite, 1 diogenite, 2 eucrites, 1 enstatite chondrite, four L3 and two H3 chondrites, 2 CM, 3 CK and 1 CV chondrites, three R chondrites, and four impact melt breccias (with affinities for H and L). Likely the most interesting sample announced in this newsletter is LAP04840, with affinity to R chondrites. This meteorite contains approximately 15% horneblende, and has mineral compositional ranges and oxygen isotopic values similar to those of R chondrites. The presence of an apparently hydrous phase in this petrologic grade 6 chondrite is very unusual, and should be of great interest to many meteoriticists.

  20. Halogenating activities detected in Antarctic macroalgae

    SciTech Connect

    Laturnus, F.; Adams, F.C.; Gomez, I.; Mehrtens, G.

    1997-03-01

    Halogenating activities were determined in samples of 18 cultivated species of brown, red and green macroalgae from the Antarctic. Activities for the halogenating organic compounds with bromide, iodide and chloride were found. Investigated red algae (rhodophytes) showed higher brominating and iodinating activities compared to brown (phaeophytes) and green (chlorophytes) algae. The highest brominating and iodinating activities were measured in the red algae Plocamium cartilagineum (1.11 {+-} 0.01 U g{sup -1} wet algal weight and 0.18 U g{sup -1} wet algal weight, respectively) and Myriogramme mangini (3.62 {+-} 0.17 U g{sup -1} wet algal weight and 4.5 U g{sup -1} wet algal weight, respectively). Chlorinating activities were detected in the red alga Plocamium cartilagineum only (0.086 U g{sup -1} wet algal weight). 30 refs., 2 figs., 1 tab.

  1. Detection of HOCl in the Antarctic stratosphere

    NASA Technical Reports Server (NTRS)

    Toon, G. C.; Farmer, C. B.

    1989-01-01

    An integrated vertical column abundance of 1.5 + or - 0.4 x 10 to the 14th molec/sq cm of HOCl has been inferred from high resolution infrared solar spectra measured by the JPL MkIV interferometer from the NASA DC-8 aircraft during flights over Antarctica in September 1987. This result was obtained by averaging spectra recorded at different times, dates, and locations, but may be considered a mid-morning measurement at a solar zenith angle of 88.2 degrees from 79 deg S, 83 deg E on September 20. This result poses an important constraint on the amount of HO(x) inside the Antarctic winter vortex and on the contribution of the HOCl catalytic cycle to the observed springtime ozone depletion.

  2. ELF/VLF Antarctic Research (Invited)

    NASA Astrophysics Data System (ADS)

    Moore, R. C.

    2013-12-01

    The University of Florida presently performs ELF/VLF measurements at Palmer Station, McMurdo Station, and South Pole Station, Antarctica. Research efforts focus on detecting and analyzing lightning-generated ELF/VLF sferics and on the remote sensing of ionospheric disturbances in the Southern hemisphere. The Antarctic ELF/VLF receivers complement a Northern hemisphere ELF/VLF monitoring array. In this paper, we present our latest observational results, including conjugate observations of lightning-induced electron precipitation, solar X-ray flares, and proton injection events. We also present a statistical analysis of lightning-generated Q-bursts and our ongoing efforts to analyze sferics generated by rocket-triggered lightning at the International Center for Lightning Research and Testing (ICLRT) at Camp Blanding, Florida. An analysis of man-made electromagnetic noise at Arrival Heights, Antarctica is also considered.

  3. Bromoalkane production by Antarctic ice algae

    NASA Technical Reports Server (NTRS)

    Sturges, W. T.; Sullivan, C. W.; Schnell, R. C.; Heidt, L. E.; Pollock, W. H.

    1993-01-01

    Ice microalgae, collected from the underside of annual sea ice in McMurdo Sound, Antarctica, were found to contain and release to seawater a number of brominated hydrocarbons. These included bromoform, dibromomethane, mixed bromochloromethanes, and methyl bromide. Atmospheric measurements in the McMurdo Sound vicinity revealed the presence of bromoform and methyl bromide in the lower atmosphere, with lowest concentrations inland, further indicating that biogenic activity in the Sound is a source of organic bromine gases to the Antarctic atmosphere. This may have important implications for boundary layer chemistry in Antarctica. In the Arctic, the presence of bromoform has been linked to loss of surface ozone in the spring. We report here preliminary evidence for similar surface ozone loss at McMurdo Station.

  4. Organic analysis of the Antarctic carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Kotra, R. K.; Shimoyama, A.; Ponnamperuma, C.; Hare, P. E.; Yanai, K.

    1981-01-01

    Thus far, organic analysis of carbonaceous chondrites has proven the only fruitful means of examining complex organic matter of extraterrestrial origin. The present paper presents the results of organic analysis of two Antarctic meteorites, Allan Hills (77306) and Yamato (74662), which may be considered free from terrestrial contamination. Ion-exchange chromatography, gas chromatography and mass spectrometery of meteorite samples reveal the presence in Yamato of 15 and in Allan Hills of 20 protein and nonprotein amino acids, the most abundant of which are glycine and alanine. Abundances of the D and L enantiomers of each amino acid are also found to be nearly equal. Data thus indicate an abiotic extraterrestrial origin for the matter, and confirm a lack of terrestrial contamination.

  5. Detection of HOCl in the Antarctic stratosphere

    SciTech Connect

    Toon, G.C.; Farmer, C.B. )

    1989-12-01

    An integrated vertical column abundance of 1.5 {plus minus} 0.4 {times} {sup +14} molec.cm{sup {minus}2} of HOCl has been inferred from high resolution infrared solar spectra measured by the JPL MkIV interferometer from the NASA DC-8 aircraft during flights over Antarctica in September 1987. This result was obtained by averaging spectra recorded at different times, dates and locations, but may be considered a mid-morning measurement at a solar zenith angle of 88.2 degrees from 79{degree}S, 83{degree}E on September 20. This result poses an important constraint on the amount of HO{sub x} inside the Antarctic winter vortex and on the contribution of the HOCl catalytic cycle to the observed spring-time ozone depletion.

  6. The Recovery of the Antarctic Ozone Hole

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.

    2004-01-01

    The ozone hole is a massive loss of ozone that annually occurs over Antarctica during the Austral spring (August-November). Man-made chlorine and bromine compounds cause the ozone hole. As opposed to local urban pollution, the hole illustrates how man-made chemicals can affect the atmosphere over enormous regions remote from their release point. These chlorine and bromine gases have long lifetimes in the atmosphere; hence, the ozone hole will slowly recover into the next few decades. In this talk I will briefly cover some of the history of the Antarctic ozone hole and the theory behind the phenomena. I will then discuss the recovery of ozone over Antarctica. State-of-the-art computer models project the recovery of the ozone hole to 1980 levels by about 2050. However, this recovery may be affected by greenhouse warming.

  7. AVHRR imagery reveals Antarctic ice dynamics

    SciTech Connect

    Bindschadler, R.A.; Vornberger, P.L. STX Corp., Lanham, MD )

    1990-06-01

    A portion of AVHRR data taken on December 5, 1987 at 06:15 GMT over a part of Antarctica is used here to show that many of the most significant dynamic features of ice sheets can be identified by a careful examination of AVHRR imagery. The relatively low resolution of this instrument makes it ideal for obtaining a broad view of the ice sheets, while its wide swath allows coverage of areas beyond the reach of high-resolution imagers either currently in orbit or planned. An interpretation is given of the present data, which cover the area of ice streams that drain the interior of the West Antarctic ice sheet into the Ross Ice Shelf. 21 refs.

  8. Joint Antarctic School Expedition - An International Collaboration for High School Students and Teachers on Antarctic Science

    NASA Astrophysics Data System (ADS)

    Botella, J.; Warburton, J.; Bartholow, S.; Reed, L. F.

    2014-12-01

    The Joint Antarctic School Expedition (JASE) is an international collaboration program between high school students and teachers from the United States and Chile aimed at providing the skills required for establishing the scientific international collaborations that our globalized world demands, and to develop a new approach for science education. The National Antarctic Programs of Chile and the United States worked together on a pilot program that brought high school students and teachers from both countries to Punta Arenas, Chile, in February 2014. The goals of this project included strengthening the partnership between the two countries, and building relationships between future generations of scientists, while developing the students' awareness of global scientific issues and expanding their knowledge and interest in Antarctica and polar science. A big component of the project involved the sharing by students of the acquired knowledge and experiences with the general public. JASE is based on the successful Chilean Antarctic Science Fair developed by Chile´s Antarctic Research Institute. For 10 years, small groups of Chilean students, each mentored by a teacher, perform experimental or bibliographical Antarctic research. Winning teams are awarded an expedition to the Chilean research station on King George Island. In 2014, the Chileans invited US participation in this program in order to strengthen science ties for upcoming generations. On King George Island, students have hands-on experiences conducting experiments and learning about field research. While the total number of students directly involved in the program is relatively small, the sharing of the experience by students with the general public is a novel approach to science education. Research experiences for students, like JASE, are important as they influence new direction for students in science learning, science interest, and help increase science knowledge. We will share experiences with the

  9. German Antarctic Receiving Station (GARS) O'Higgins

    NASA Technical Reports Server (NTRS)

    Neidhardt, Alexander; Ploetz, Christian; Kluegel, Thomas

    2013-01-01

    In 2012, the German Antarctic Receiving Station (GARS) O'Higgins contributed to the IVS observing program with four observation sessions. Maintenance and upgrades were made, and a new replacement dewar is under construction in the observatory at Yebes, Spain.

  10. Ice sheets. Volume loss from Antarctic ice shelves is accelerating.

    PubMed

    Paolo, Fernando S; Fricker, Helen A; Padman, Laurie

    2015-04-17

    The floating ice shelves surrounding the Antarctic Ice Sheet restrain the grounded ice-sheet flow. Thinning of an ice shelf reduces this effect, leading to an increase in ice discharge to the ocean. Using 18 years of continuous satellite radar altimeter observations, we have computed decadal-scale changes in ice-shelf thickness around the Antarctic continent. Overall, average ice-shelf volume change accelerated from negligible loss at 25 ± 64 cubic kilometers per year for 1994-2003 to rapid loss of 310 ± 74 cubic kilometers per year for 2003-2012. West Antarctic losses increased by ~70% in the past decade, and earlier volume gain by East Antarctic ice shelves ceased. In the Amundsen and Bellingshausen regions, some ice shelves have lost up to 18% of their thickness in less than two decades. PMID:25814064

  11. IceBridge Kicks off Antarctic 2010 Campaign

    NASA Video Gallery

    On October 18th, NASA's Operation IceBridge scientists and the DC-8 crew departed for Punta Arenas, Chile, where they will begin the Antarctic 2010 phase of the mission. For the next five weeks, in...

  12. Tectonic, Climatic, and Cryospheric Evolution of the Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2013-06-01

    For millennia, Antarctica has been a frozen continent, a land of ice and snow where complex life persists rather than thrives. But Antarctica has not always been this way. Millions of years ago the southern continent was teeming with life. Changing oceans and a plummeting atmospheric carbon dioxide concentration drove a dramatic evolution of the Antarctic continent. To provide a record of these ancient climatic shifts, the 2005-2006 SHALDRIL drilling program collected sediment cores from the bed of the iceberg-filled seas off the Antarctic Peninsula. In the AGU book Tectonic, Climatic, and Cryospheric Evolution of the Antarctic Peninsula, editors John B. Anderson and Julia S. Wellner draw on the findings garnered from SHALDRIL to explore the changing Antarctic Peninsula. In this interview, Eos talks to John B. Anderson.

  13. Coordinated Analysis of Isotopic Anomalies in Antarctic Micrometeorites

    NASA Astrophysics Data System (ADS)

    Haenecour, P.; Floss, C.; Wang, A.; Yada, T.

    2014-06-01

    We carry out coordinated analysis (NanoSIMS 50, Auger Nanoprobe, Raman spectroscopy) of presolar grains (silicates, oxides, SiC) and ^15N-enriched carbonaceous matter in fine-grained Antarctic micrometeorites.

  14. Amino Acids in the Antarctic Martian Meteorite MIL03346

    NASA Technical Reports Server (NTRS)

    Glavin, D. P.; Aubrey, A.; Dworkin, J. P.; Botta, O.; Bada, J. L.

    2005-01-01

    The report by McKay et al. that the Martian meteorite ALH84001 contains evidence for life on Mars remains controversial. Of central importance is whether ALH84001 and other Antarctic Martian meteorites contain endogenous organic compounds. In any investigation of organic compounds possibly derived from Mars it is important to focus on compounds that play an essential role in biochemistry as we know it and that have properties such as chirality which can be used to distinguish between biotic versus abiotic origins. Amino acids are one of the few compounds that fulfill these requirements. Previous analyses of the Antarctic Martian meteorites ALH84001 and EETA79001 have shown that these meteorites contain low levels of terrestrial amino acid contamination derived from Antarctic ice meltwater. Here we report preliminary amino acid investigations of a third Antarctic Martian meteorite MIL03346 which was discovered in Antarctica during the 2003-04 ANSMET season. Additional information is included in the original extended abstract

  15. Rayleigh-wave group velocity distribution in the Antarctic region

    NASA Astrophysics Data System (ADS)

    Kobayashi, Reiji; Zhao, Dapeng

    2004-03-01

    We determined 2D group velocity distribution of Rayleigh waves at periods of 20-150 s in the Antarctic region using a tomographic inversion technique. The data are recorded by both permanent networks and temporary arrays. In East Antarctica the velocities are high at periods of 90-150 s, suggesting that the root of East Antarctica is very deep. The velocities in West Antarctica are low at all periods, which may be related to the volcanic activity and the West Antarctic Rift System. Low velocity anomalies appear at periods of 40-140 s along the Southeastern Indian Ridge and the western part of the Pacific Antarctic Ridge. The velocities are only slightly low around the Atlantic Indian Ridge, Southwestern Indian Ridge, and the eastern part of the Pacific Antarctic Ridge, where the spreading rates are small. Around two hotspots, the Mount Erebus and Balleny Islands, the velocity is low at periods of 50-150 s.

  16. Antarctic role in multi-centennial climate variability

    NASA Astrophysics Data System (ADS)

    Bakker, Pepijn; Clark, Peter U.; Golledge, Nicolas R.; Schmittner, Andreas

    2016-04-01

    Proxy-based reconstructions have revealed an important lack of multi-centennial climate variability in global climate models. Here we use a high-resolution ice-sheet model in combination with global climate simulations to show that internal variability in discharge of the West Antarctic Ice Sheet is a potentially important driver of multi-centennial climate variability. Variations in discharge impact the formation of Antarctic Bottom Water, that in turn impacts the climate at the earth's surface and in the deep ocean, in both near-field and far-field regions, through variations in the strength of the Atlantic meridional overturning circulation. If indeed interactions between the West Antarctic Ice Sheet and the climate on multi-centennial timescales are important, studying them in high resolution climate records has good potential to provide constraints on the dynamics of the West Antarctic Ice Sheet and its contribution to future sea-level rise.

  17. Surface destabilisation by the invasive burrowing engineer Mus musculus on a sub-Antarctic island

    NASA Astrophysics Data System (ADS)

    Eriksson, Bert; Eldridge, David J.

    2014-10-01

    Invasive species are known to have substantial trophic effects on ecosystems and ecosystem processes. The invasion of the house mouse (Mus musculus) onto sub-Antarctic islands has had a devastating effect on plants, invertebrates, and birds with substantial changes in ecosystem functions. Less well understood, however, are the nontrophic, geomorphic effects of mice resulting from their burrowing activities. We examined the extent of burrow construction by M. musculus across an area of about 20 ha on Marion Island and the effects of burrows on water flow and sediment movement. We recorded a density of 0.59 ± 0.48 (mean ± SD) burrows m- 2, with more burrows at lower altitudes and shallower slopes, and twice the density in the solifluction risers (0.86 ± 0.54 m- 2) than the intervening terraces or treads (0.40 ± 0.51 m- 2). Most burrows were dug horizontally into the slope and tended to extend about 20 cm deep before turning. A very conservative estimate of sediment removed from burrows from this depth is 2.4 t ha- 1. However, taking into account more detailed data on burrow morphology based on excavations, actual amounts may be closer to 8.4 t ha- 1. Average soil displacement rate for a single burrow, measured over 5 days, was 0.18 kg burrow- 1 day- 1. Burrows acted as conduits for water and warmer air. Stones at burrow entrances were moved eight times farther by water (10.4 cm) than those not associated with burrows. Similarly, temperatures adjacent to burrow entrances were 4.1 °C higher than sites 10 cm away. Together our data indicate that mice are having substantial deleterious and geomorphic effects on sub-Antarctic ecosystems through their burrowing. With lower rates of mouse mortality resulting from warmer climates predicted under global climate models, we can expect an increase in damage resulting from mouse activity.

  18. Morphogenesis of Antarctic Paleosols: Martian Analogue

    NASA Astrophysics Data System (ADS)

    Mahaney, W. C.; Dohm, J. M.; Baker, V. R.; Newsom, Horton E.; Malloch, D.; Hancock, R. G. V.; Campbell, Iain; Sheppard, D.; Milner, M. W.

    2001-11-01

    Samples of horizons in paleosols from the Quartermain Mountains of the Antarctic Dry Valleys (Aztec and New Mountain areas) were analyzed for their physical characteristics, mineralogy, chemical composition, and microbiology to determine the accumulation and movement of salts and other soluble constituents and the presence/absence of microbial populations. Salt concentrations are of special interest because they are considered to be a function of age, derived over time, in part from nearby oceanic and high-altitude atmospheric sources. The chemical composition of ancient Miocene-age paleosols in these areas is the direct result of the deposition and weathering of airborne-influxed salts and other materials, as well as the weathering of till derived principally from local dolerite and sandstone outcrops. Paleosols nearer the coast have greater contents of Cl, whereas near the inland ice sheet, nitrogen tends to increase on a relative basis. The accumulation and vertical distribution of salts and other soluble chemical elements indicate relative amounts of movement in the profile over long periods of time, in the order of several million years. Four of the six selected subsamples from paleosol horizons in two ancient soil profiles contained nil concentrations of bacteria and fungi. However, two horizons at depths of between 3 and 8 cm, in two profiles, yielded several colonies of the fungi Beauveria bassiana and Penicillium brevicompactum, indicating very minor input of organic carbon. Beauveria bassiana is often reported in association with insects and is used commercially for the biological control of some insect pests. Penicillium species are commonly isolated from Arctic, temperate, and tropical soils and are known to utilize a wide variety of organic carbon and nitrogen compounds. The cold, dry soils of the Antarctic bear a close resemblance to various present and past martian environments where similar weathering could occur and possible microbial populations

  19. Glacial morphology and depositional sequences of the Antarctic Continental Shelf

    USGS Publications Warehouse

    ten Brink, U.S.; Schneider, Christopher

    1995-01-01

    Proposes a simple model for the unusual depositional sequences and morphology of the Antarctic continental shelf. It considers the regional stratal geometry and the reversed morphology to be principally the results of time-integrated effects of glacial erosion and sedimentation related to the location of the ice grounding line. The model offers several guidelines for stratigraphic interpretation of the Antarctic shelf and a Northern Hemisphere shelf, both of which were subject to many glacial advances and retreats. -Authors

  20. Bird activity levels related to weather

    USGS Publications Warehouse

    Robbins, C.S.

    1981-01-01

    The Breeding Bird Survey data bank serves as a primary source for studying effects of sky cover, wind speed, and temperature on bird census results. Other standardized methods, such as spot-mapping (Breeding Bird Census), point counts, banding, and the Winter Bird Survey, provide additional, but limited, means of assessing effects of weather. Numbers of songbirds detected are generally inversely correlated with wind speed, but hawks often are seen in larger numbers on windy days. Rain greatly reduces the numbers of birds detected. Cloud cover has relatively little influence on early morning bird counts during the peak of the breeding season. Fog selectively favors auditory detections of some species. Counts of many species are correlated with temperature, but effects are minor unless temperatures are extreme. Under marginal weather conditions, total species observed may be nearly normal, whereas number of individuals observed is reduced, as is the opportunity to record simultaneous registrations

  1. Chlamydial infections in free-living birds

    USGS Publications Warehouse

    Brand, C.J.

    1989-01-01

    Most studies of chlamydial infections in free-living wild birds have been limited to surveys for the presence of Chlamydia psittaci or antibody to C psittaci and have largely been done in association with the identification of chlamydiosis in human beings, commercial fowl, or pet birds. The emphasis of these studies has been to determine the prevalence of infection and the potential role of wild birds in the spread of chlamydiae to domestic birds and human beings. Little is known about the epizootiology of chlamydiosis in free-living birds or its affect on their population dynamics. The following article is a summary of reported studies of chlamydiosis in free-living wild birds in relation to host range, ecologic aspects of transmission and maintenance, and the prevalence of disease.

  2. A Bivalve Proxy for Neogene Antarctic Shelf Marine Environments

    NASA Astrophysics Data System (ADS)

    Clark, N. A.; Williams, M.; Quilty, P. G.; Leng, M. J.; Zalasiewicz, J. A.; Smellie, J.; Dowsett, H. J.

    2012-12-01

    The Neogene shallow-marine successions of the Antarctic Peninsula and of the East Antarctic region preserve rich assemblages of bivalve molluscs. These bivalve molluscs provide a detailed record of palaeoseasonality in the chemical signature and morphology of their shells that can be used to assess sea temperatures and sea ice extent for the Antarctic shelf during the Pliocene. Analyses identify the following. 1) Neogene bivalves from James Ross Island, Antarctic Peninsula, comprise material of late Miocene through to late Pliocene age. Results identify warm (ca. 3-10 °C) early Pliocene sea temperatures, and cooler late Pliocene sea temperatures (ca. 0-4 °C), and flag a cooling trend which is consistent with the evolution of polar climate through this interval. 2) Neogene bivalves from the Larsemann Hills, East Antarctic, identify generally warmer than present sea temperatures (ca. 0-11 °C) in the early Pliocene consistent with data from other fossil groups of this age, including dolphins and silicoflagellates. The new data may provide significant ground truth for climate models assessing the Southern Ocean and Antarctic shelf climate.

  3. Towards a Circum-Antarctic Holocene Paleointensity Record

    NASA Astrophysics Data System (ADS)

    Brachfeld, S.; Kissel, C.; Laj, C.; Willmott, V.

    2005-12-01

    New Holocene geomagnetic paleointensity records have been constructed from the Western Antarctic Peninsula (WAP), Eastern Antarctic Peninsula (EAP), and from the East Antarctic Margin (EAM). The goal of this work is to develop Antarctic paleointensity reference curves for correlation and dating of Antarctic continental shelf sediments. Sediment sequences deposited in fjords and inner shelf basins contain Holocene sections of 3-meters to more than 20-meters, recording the last deglaciation, the paleohistory of ice shelves, and shifting paleoceanographic conditions. However, these records suffer from a lack biogenic calcite for radiocarbon dating. Diatomaceous mud contains sufficient acid insoluble organic matter (aiom) for radiocarbon dating and hence an independent chronology. However, laminated oozes yield shallow inclinations, hence the remanence vector is suspect. Bioturbated diatomaceous mud and diatom-poor muds yield excellent directional records and satisfy the criteria for magnetic uniformity, however the organic content is low and aiom dates can be problematic. Our paleointensity records show the broad pattern of higher intensity during the late Holocene, and lower intensity during the early to middle Holocene, similar to the sinusoidal intensity pattern seen in global absolute and relative paleointensity stacks. Several of the records contain 3 to 4 late Holocene peaks with 1000-year wavelengths that are similar in amplitude and duration to features seen in northern hemisphere lacustrine and marine records. Here we evaluate the local versus regional character of the Antarctic paleointensity records, and the consistency of aiom-dated versus paleointensity-tuned chronologies.

  4. Effect of Antarctic solar radiation on sewage bacteria viability.

    PubMed

    Hughes, Kevin A

    2005-06-01

    The majority of coastal Antarctic research stations discard untreated sewage waste into the near-shore marine environment. However, Antarctic solar conditions are unique, with ozone depletion increasing the proportion of potentially damaging ultraviolet-B (UV-B) radiation reaching the marine environment. This study assessed the influence of Antarctic solar radiation on the viability of Escherichia coli and sewage microorganisms at Rothera Research Station, Adelaide Island, Antarctic Peninsula. Cell viability decreased with increased exposure time and with exposure to shorter wavelengths of solar radiation. Cell survival also declined with decreasing cloud cover, solar zenith angle and ozone column depth. However, particulates in sewage increased the persistence of viable bacteria. Ultraviolet radiation doses over Rothera Point were highest during the austral summer. During this time, solar radiation may act to partially reduce the number of viable sewage-derived microorganisms in the surface seawater around Antarctic outfalls. Nevertheless, this effect is not reliable and every effort should be made to fully treat sewage before release into the Antarctic marine environment. PMID:15927228

  5. Evaluation of semen from nondomestic birds

    USGS Publications Warehouse

    Gee, G.F.

    1997-01-01

    Aspects of poultry Al technology are applicable to nondomestic birds. However, modifications in the methods of semen collection, evaluation, and insemination are often necessary to accomodate either the bird's size, sperm numbers, or. female anatomy. This section provides a brief overview of procedures used to evaluate semen from nondomestic birds. Unless specified, materials, reagents, etc., are identical to those used in evaluating poultry semen (see appropriate chapters).

  6. Electrospray ionization-tandem mass spectrometry analysis of phospholipid molecular species from Antarctic and non-Antarctic yeasts.

    PubMed

    Bhuiyan, Mohammad; Tucker, David; Watson, Kenneth

    2014-10-01

    High performance liquid chromatography-electrospray ionization tandem mass spectrometry was applied to the comprehensive analysis of phospholipids from seven Antarctic and seven non-Antarctic yeasts. Identification of specific fatty acyl moieties to the sn-1 and sn-2 positions of phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylserine (PS) and phosphatidylinositol (PI) were determined by relative abundance of fragment ions associated with formation of carboxylate anions and loss of fragment ions as free fatty carboxylic acid and ketene. Modulations with growth temperature in fatty acyl moieties in the sn-1 and sn-2 positions were characterized. Principal component analysis demonstrated that PE, PC and to a lesser extent PS, but not PI, were grouped into three distinct clusters consisting of seven Antarctic yeasts (Cryptococcus victoriae, Holtermanniella wattica, H. nyarrowii, Candida psychrophila, Leucosporidium fellii, Glaciozyma antarctica, Rhodotorula mucilaginosa), four non-Antarctic yeasts (C. albicans, Zygosaccharomyces rouxii, Cr. humicolus, R. mucilaginosa) and three strains of Saccharomyces cerevisiae. PMID:25019517

  7. Development of a regional glycerol dialkyl glycerol tetraether (GDGT)-temperature calibration for Antarctic and sub-Antarctic lakes

    NASA Astrophysics Data System (ADS)

    Foster, Louise C.; Pearson, Emma J.; Juggins, Steve; Hodgson, Dominic A.; Saunders, Krystyna M.; Verleyen, Elie; Roberts, Stephen J.

    2016-01-01

    A regional network of quantitative reconstructions of past climate variability is required to test climate models. In recent studies, temperature calibration models based on the relative abundances of sedimentary glycerol dialkyl glycerol tetraethers (GDGTs) have enabled past temperature reconstructions in both marine and terrestrial environments. Nevertheless, to date these methods have not been widely applied in high latitude environments due to poor performance of the GDGT-temperature calibrations at lower temperatures. To address this we studied 32 lakes from Antarctica, the sub-Antarctic Islands and Southern Chile to: 1) quantify their GDGT composition and investigate the environmental controls on GDGT composition; and 2) develop a GDGT-temperature calibration model for inferring past temperatures from Antarctic and sub-Antarctic lakes. GDGTs were found in all 32 lakes studied and in 31 lakes branched GDGTs (brGDGTs) were the dominant compounds. Statistical analyses of brGDGT composition in relation to temperature, pH, conductivity and water depth showed that the composition of brGDGTs is strongly correlated with mean summer air temperature (MSAT). This enabled the development of the first regional brGDGT-temperature calibration for use in Antarctic and sub-Antarctic lakes using four brGDGT compounds (GDGT-Ib, GDGT-II, GDGT-III and GDGT-IIIb). A key discovery was that GDGT-IIIb is of particular importance in cold lacustrine environments. The addition of this compound significantly improved the model's performance from r2 = 0.67, RMSEP-LOO (leave-one-out) = 2.23 °C, RMSEP-H (h-block) = 2.37 °C when applying the re-calibrated global GDGT-temperature calibration to our Antarctic dataset to r2 = 0.83, RMSEP-LOO = 1.68 °C, RMSEP-H = 1.65 °C for our new Antarctic calibration. This shows that Antarctic and sub-Antarctic, and possibly other high latitude, palaeotemperature reconstructions should be based on a regional GDGT-temperature calibration where specific

  8. Habitat size and bird community management

    USGS Publications Warehouse

    Anderson, S.H.; Robbins, C.S.

    1981-01-01

    The purpose of this paper is to review the results in the literature that show the effect of area of forest on nesting migratory bird species, and to present the results of additional field work that we have conducted in forest habitats in western Maryland. These results indicate the area sensitivity of many long distance migrants. Because 80 to 95 percent of the breeding birds in the northeastern deciduous forest are neotropical migrants, the changes in bird species composition as a result of forest fragmentation can be immense. Management strategies based on habitat size are suggested to assist in maintaining communities of nesting migratory birds.

  9. Bird sexing by Fourier transform infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Steiner, Gerald; Bartels, Thomas; Krautwald-Junghanns, Maria-Elisabeth; Koch, Edmund

    2010-02-01

    Birds are traditionally classified as male or female based on their anatomy and plumage color as judged by the human eye. Knowledge of a bird's gender is important for the veterinary practitioner, the owner and the breeder. The accurate gender determination is essential for proper pairing of birds, and knowing the gender of a bird will allow the veterinarian to rule in or out gender-specific diseases. Several biochemical methods of gender determination have been developed for avian species where otherwise the gender of the birds cannot be determined by their physical appearances or characteristics. In this contribution, we demonstrate that FT-IR spectroscopy is a suitable tool for a quick and objective determination of the bird's gender. The method is based on differences in chromosome size. Male birds have two Z chromosomes and female birds have a W-chromosome and a Z-chromosome. Each Z-chromosome has approx. 75.000.000 bps whereas the W-chromosome has approx. 260.00 bps. This difference can be detected by FT-IR spectroscopy. Spectra were recorded from germ cells obtained from the feather pulp of chicks as well as from the germinal disk of fertilized but non-bred eggs. Significant changes between cells of male and female birds occur in the region of phosphate vibrations around 1080 and 1120 cm-1.

  10. Flight performance of the largest volant bird

    PubMed Central

    Ksepka, Daniel T.

    2014-01-01

    Pelagornithidae is an extinct clade of birds characterized by bizarre tooth-like bony projections of the jaws. Here, the flight capabilities of pelagornithids are explored based on data from a species with the largest reported wingspan among birds. Pelagornis sandersi sp. nov. is represented by a skull and substantial postcranial material. Conservative wingspan estimates (∼6.4 m) exceed theoretical maximums based on extant soaring birds. Modeled flight properties indicate that lift:drag ratios and glide ratios for P. sandersi were near the upper limit observed in extant birds and suggest that pelagornithids were highly efficient gliders, exploiting a long-range soaring ecology. PMID:25002475

  11. COMPLEX EVOLUTION OF BILE SALTS IN BIRDS

    PubMed Central

    Hagey, Lee R.; Vidal, Nicolas; Hofmann, Alan F.; Krasowski, Matthew D.

    2010-01-01

    Bile salts are the major end-metabolites of cholesterol and are important in lipid digestion and shaping of the gut microflora. There have been limited studies of bile-salt variation in birds. The purpose of our study was to determine bile-salt variation among birds and relate this variation to current avian phylogenies and hypotheses on the evolution of bile salt pathways. We determined the biliary bile-salt composition of 405 phylogenetically diverse bird species, including 7 paleognath species. Bile salt profiles were generally stable within bird families. Complex bile-salt profiles were more common in omnivores and herbivores than in carnivores. The structural variation of bile salts in birds is extensive and comparable to that seen in surveys of bile salts in reptiles and mammals. Birds produce many of the bile salts found throughout nonavian vertebrates and some previously uncharacterized bile salts. One difference between birds and other vertebrates is extensive hydroxylation of carbon-16 of bile salts in bird species. Comparison of our data set of bird bile salts with that of other vertebrates, especially reptiles, allowed us to infer evolutionary changes in the bile salt synthetic pathway. PMID:21113274

  12. Capturing birds with mist nets: A review

    USGS Publications Warehouse

    Keyes, B.E.; Grue, C.E.

    1982-01-01

    Herein we have tried to provide a comprehensive review of mist-netting techniques suitable for both novice and experienced netters. General mist-netting procedures and modifications developed by netters for particular bird species and habitats are included. Factors which influence capture success, including site selection, net specifications and placement, weather, and time of day, are discussed. Guidelines are presented for the care of netted birds and the use of mist-net data in the study of bird communities. The advantages of the use of mist nets over other methods of capturing birds are also discussed.

  13. Annotated checklist of Georgia birds

    USGS Publications Warehouse

    Beaton, G.; Sykes, P.W., Jr.; Parrish, J.W., Jr.

    2003-01-01

    This edition of the checklist includes 446 species, of which 407 are on the Regular Species List, 8 on the Provisional, and 31 on the Hypothetical. This new publication has been greatly expanded and much revised over the previous checklist (GOS Occasional Publ. No. 10, 1986, 48 pp., 6x9 inches) to a 7x10-inch format with an extensive Literature Cited section added, 22 species added to the Regular List, 2 to the Provisional List, and 9 to the Hypothetical List. Each species account is much more comprehensive over all previous editions of the checklist. Among some of the new features are citations for sources of most information used, high counts of individuals for each species on the Regular List, extreme dates of occurrence within physiographic regions, a list of abbreviations and acronyms, and for each species the highest form of verifiable documentation given with its repository institution with a catalog number. This checklist is helpful for anyone working with birds in the Southeastern United States or birding in that region. Sykes' contribution to this fifth edition of the Annotated Checklist of Georgia Birds includes: suggestion of the large format and spiral binding, use of Richard A. Parks' painting of the Barn Owl on the front cover, use of literature citations throughout, and inclusion of high counts for each species. Sykes helped plan all phases of the publication, wrote about 90% of the Introduction and 84 species accounts (Osprey through Red Phalarope), designed the four maps in the introduction section and format for the Literature Cited, and with Giff Beaton designed the layout of the title page.

  14. Foot abnormalities of wild birds

    USGS Publications Warehouse

    Herman, C.M.; Locke, L.N.; Clark, G.M.

    1962-01-01

    The various foot abnormalities that occur in birds, including pox, scaly-leg, bumble-foot, ergotism and freezing are reviewed. In addition, our findings at the Patuxent Wildlife Research Center include pox from dove, mockingbird, cowbird, grackle and several species of sparrows. Scaly-leg has been particularly prevalent on icterids. Bumble foot has been observed in a whistling swan and in a group of captive woodcock. Ergotism is reported from a series of captive Canada geese from North Dakota. Several drug treatments recommended by others are presented.

  15. Common Emergencies in Pet Birds.

    PubMed

    Stout, Jane D

    2016-05-01

    Treating avian emergencies can be a challenging task. Pet birds often mask signs of illness until they are critically ill and require quick initiation of supportive care with minimal handling to stabilize them. This article introduces the clinician to common avian emergency presentations and details initial therapeutics and diagnostics that can be readily performed in the small-animal emergency room. Common disease presentations covered include respiratory and extrarespiratory causes of dyspnea, gastrointestinal signs, reproductive disease, neurologic disorders, trauma, and toxin exposure. The duration and severity of the avian patient's disease and the clinician's initiation of appropriate therapy often determines clinical outcome. PMID:26948267

  16. 75 FR 3888 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    ... Register on November 20, 2009 (74 FR 60228), to propose migratory bird subsistence harvest regulations in... Fish and Wildlife Service 50 CFR Part 92 RIN 1018-AW67 Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska During the 2010 Season AGENCY: Fish and Wildlife...

  17. 78 FR 67183 - Proposed Information Collection; Migratory Bird Harvest Information Program and Migratory Bird...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-08

    ... Fish and Wildlife Service Proposed Information Collection; Migratory Bird Harvest Information Program and Migratory Bird Surveys AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice; request for... Bird Treaty Act (16 U.S.C. 703-711) and the Fish and Wildlife Act of 1956 (16 U.S.C. 742d)...

  18. Avian Assemblages at Bird Baths: A Comparison of Urban and Rural Bird Baths in Australia.

    PubMed

    Cleary, Gráinne P; Parsons, Holly; Davis, Adrian; Coleman, Bill R; Jones, Darryl N; Miller, Kelly K; Weston, Michael A

    2016-01-01

    Private gardens provide habitat and resources for many birds living in human-dominated landscapes. While wild bird feeding is recognised as one of the most popular forms of human-wildlife interaction, almost nothing is known about the use of bird baths. This citizen science initiative explores avian assemblages at bird baths in private gardens in south-eastern Australia and how this differs with respect to levels of urbanisation and bioregion. Overall, 992 citizen scientists collected data over two, four-week survey periods during winter 2014 and summer 2015 (43% participated in both years). Avian assemblages at urban and rural bird baths differed between bioregions with aggressive nectar-eating species influenced the avian assemblages visiting urban bird baths in South Eastern Queensland, NSW North Coast and Sydney Basin while introduced birds contributed to differences in South Western Slopes, Southern Volcanic Plains and Victorian Midlands. Small honeyeaters and other small native birds occurred less often at urban bird baths compared to rural bird baths. Our results suggest that differences between urban versus rural areas, as well as bioregion, significantly influence the composition of avian assemblages visiting bird baths in private gardens. We also demonstrate that citizen science monitoring of fixed survey sites such as bird baths is a useful tool in understanding large-scale patterns in avian assemblages which requires a vast amount of data to be collected across broad areas. PMID:26962857

  19. Avian Assemblages at Bird Baths: A Comparison of Urban and Rural Bird Baths in Australia

    PubMed Central

    Cleary, Gráinne P.; Parsons, Holly; Davis, Adrian; Coleman, Bill R.; Jones, Darryl N.; Miller, Kelly K.; Weston, Michael A.

    2016-01-01

    Private gardens provide habitat and resources for many birds living in human-dominated landscapes. While wild bird feeding is recognised as one of the most popular forms of human-wildlife interaction, almost nothing is known about the use of bird baths. This citizen science initiative explores avian assemblages at bird baths in private gardens in south-eastern Australia and how this differs with respect to levels of urbanisation and bioregion. Overall, 992 citizen scientists collected data over two, four-week survey periods during winter 2014 and summer 2015 (43% participated in both years). Avian assemblages at urban and rural bird baths differed between bioregions with aggressive nectar-eating species influenced the avian assemblages visiting urban bird baths in South Eastern Queensland, NSW North Coast and Sydney Basin while introduced birds contributed to differences in South Western Slopes, Southern Volcanic Plains and Victorian Midlands. Small honeyeaters and other small native birds occurred less often at urban bird baths compared to rural bird baths. Our results suggest that differences between urban versus rural areas, as well as bioregion, significantly influence the composition of avian assemblages visiting bird baths in private gardens. We also demonstrate that citizen science monitoring of fixed survey sites such as bird baths is a useful tool in understanding large-scale patterns in avian assemblages which requires a vast amount of data to be collected across broad areas. PMID:26962857

  20. DEVELOPMENT OF A BIRD INTEGRITY INDEX: USING BIRD ASSEMBLAGES AS INDICATORS OF RIPARIAN CONDITION

    EPA Science Inventory

    We describe the development of a Bird Integrity Index (Bll) that uses bird assemblage information to assess human impacts on 13 stream reaches in the Willamette Valley, Oregon. We used bird survey field data to test 62 candidate metrics that were expected to respond positively or...

  1. 78 FR 75321 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-11

    ...The U.S. Fish and Wildlife Service (Service or we) proposes migratory bird subsistence harvest regulations in Alaska for the 2014 season. These regulations would enable the continuation of customary and traditional subsistence uses of migratory birds in Alaska and prescribe regional information on when and where the harvesting of birds may occur. These regulations were developed under a......

  2. Dynamic Antarctic ice-sheet response to deglacial meltwater pulses

    NASA Astrophysics Data System (ADS)

    Weber, Michael; Clark, Peter U.; Timmermann, Axel; Lohmann, Gerrit; Kuhn, Gerhard; Sprenk, Daniela; Gladstone, Rupert

    2013-04-01

    Reconstruction of the last global sea level rise faces uncertainties because only a few robust data evidences are available for Antarctic ice sheets. Deglacial dynamics have mostly been inferred from shallow-water cores on the shelf, where decisive changes are either erased by grounding ice or occur in condensed, lithologically complex successions with partially reversed and generally unreliable 14C ages. Previous modeling studies reconstruct a late ice-sheet retreat starting around 12 ka BP and ending around 7 ka BP with a large impact of an unstable West Antarctic Ice Sheet (WAIS) and a small impact of a stable East Antarctic Ice Sheet (EAIS). However, new findings from two deepwater cores from the Scotia Sea challenge these reconstructions and call for a principal revision of the Antarctic deglacial history. The well-dated sites (Weber et al., 2012, Quaternary Science Reviews) provide the first integrative and representative record of Antarctic Ice Sheet instability. They are located in the central transport route of virtually all Antarctic icebergs, the so-called Iceberg Alley, and demonstrate a highly dynamic Antarctic Ice Sheet during the last deglaciation with eight distinct phases of enhanced iceberg routing, dubbed Antarctic Ice Sheet Events (AIE), in contrast to existing models of a late and monotonous ice-sheet retreat which implied only little contribution to the last, natural, sea-level rise 19,000 to 9,000 years ago. We found the first direct evidence for an Antarctic contribution to Meltwater Pulse 1A in the flux rates of ice-rafted debris. Using an ensemble of transient deglacial model simulations we could show that increased export of warmer Circumpolar Deep Water towards Antarctica contributed to Antarctic Ice Sheet melt by ocean thermal forcing (Weber et al., Science, in review). These new findings hold the potential to substantially revise and improve our understanding of the transient response of the ice sheet to external and internal forcings

  3. Intestinal spirochaetes (genus Brachyspira) colonise wild birds in the southern Atlantic region and Antarctica

    PubMed Central

    Jansson, Désirée S.; Mushtaq, Memoona; Johansson, Karl-Erik; Bonnedahl, Jonas; Waldenström, Jonas; Andersson, Dan I.; Broman, Tina; Berg, Charlotte; Olsen, Björn

    2015-01-01

    Introduction The genus Brachyspira contains well-known enteric pathogens of veterinary significance, suggested agents of colonic disease in humans, and one potentially zoonotic agent. There are recent studies showing that Brachyspira are more widespread in the wildlife community than previously thought. There are no records of this genus in wildlife from the southern Atlantic region and Antarctica. Our aim was therefore, to determine whether intestinal spirochaetes of genus Brachyspira colonise marine and coastal birds in this region. Method Faecal samples were collected from marine and coastal birds in the southern Atlantic region, including sub-Antarctic islands and Antarctica, in 2002, 2009, and 2012, with the aim to isolate and characterise zoonotic agents. In total, 205 samples from 11 bird species were selectively cultured for intestinal spirochaetes of genus Brachyspira. To identify isolates to species level, they were subjected to phenotyping, species-specific polymerase chain reactions, sequencing of partial 16S rRNA, NADH oxidase (nox), and tlyA genes, and phylogenetic analysis. Antimicrobial susceptibility tests were performed. Results Fourteen unique strains were obtained from 10 birds of three species: four snowy sheathbills (Chionis albus), three kelp geese (Chloephaga hybrida subsp. malvinarum), and three brown skua (Stercorarius antarcticus subsp. lonnbergi) sampled on the Falkland Islands, Tierra del Fuego in Argentina, South Georgia, South Shetland Islands, and the Antarctic Peninsula. Five Brachyspira strains were closely related to potentially enteropathogenic Brachyspira sp. of chickens: B. intermedia (n=2, from snowy sheathbills), and B. alvinipulli (n=3, from a kelp goose and two snowy sheathbills). Three strains from kelp geese were most similar to the presumed non-pathogenic species ‘B. pulli’ and B. murdochii, whereas the remaining six strains could not be attributed to currently known species. No isolates related to human strains were

  4. 78 FR 66074 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... create lesson plans about Antarctic Exploration that focus on science, technology, engineering or mathematics aspects of the historic Antarctic expeditions. The lesson plans would be appropriate for...

  5. The circum-Antarctic sedimentary record; a dowsing rod for Antarctic ice in the Eocene

    NASA Astrophysics Data System (ADS)

    Scher, H.

    2012-12-01

    Arguments for short-lived Antarctic glacial events during the Eocene (55-34 Ma) are compelling, however the paleoceanographic proxy records upon which these arguments are based (e.g., benthic δ18O, eustatic sea level, deep sea carbonate deposition) are global signals in which the role of Antarctic ice volume variability is ambiguous. That is to say, the proxy response to ice volume may be masked other processes. As a result broad correlations between proxies for ice volume are lacking during suspected Eocene glacial events. I will present a more direct approach for detecting Antarctic ice sheets in the Eocene; utilizing provenance information derived from the radiogenic isotopic composition of the terrigenous component of marine sediments near Antarctica. The method relies on knowledge that marine sediments represent a mixture derived from different basement terrains with different isotopic fingerprints. A key issue when using sedimentary deposits to characterize continental sediment sources is to deconvolve different sources from the mixed signal of the bulk sample. The pioneering work of Roy et al. (2007) and van de Flierdt et al. (2007) represents a major advance in Antarctic provenance studies. It is now known that the isotopic composition of neodymium (Nd) and hafnium (Hf) in modern circum-Antarctic sediments are distributed in a pattern that mimics the basement age of sediment sources around Antarctica. For this study I selected two Ocean Drilling Program (ODP) sites on southern Kerguelen Plateau (ODP Sites 738 and 748) because of their proximity to Prydz Bay, where Precambrian sediment sources contribute to extremely nonradiogenic isotopic signatures in modern sediments in the Prydz Bay region. New detrital Nd isotope records from these sediment cores reveal an Nd isotope excursion at the Bartonian/Priabonian boundary (ca. 37 Ma) that coincides with a 0.5 ‰ increase in benthic foram δ18O values. Detrital sediment ɛNd values are around -12 in intervals

  6. Eye lesions in pet birds.

    PubMed

    Tsai, S S; Park, J H; Hirai, K; Itakura, C

    1993-03-01

    Amongst eye lesions in birds that died in quarantine, cataracts were the most common disorders (37/241, 15.4%), being prevalent in the annular pads of cockatiels (Nymphicus hollandicus), Amazon parrots (Amazona aestiva aestiva) and budgerigars (Melopsittacus undulatus). The incidence in male birds was more than twice that in females. Deposition of crystals, mostly in the cornea, was the second most frequent lesion (21/293, 8.7%), mainly found in cockatiels, parakeets (Psittacula krameri manillensis), Amazon parrots (Amazona aestiva aestiva), budgerigars and finches (Poephila gouldiae gouldiae). These corneal crystals were negative to PAS and Kossa's stains. Six parakeets (Psittacula krameri manillensis) had calcium salts deposited in the inner plexiform layer of the retina and occasionally in the iris and ciliary body. Neither inflammation nor neo-vascularization was observed when cataracts, corneal crystalline deposition, and retinal and ciliary calcification were present. Intranuclear inclusion bodies typical for papovavirus infection were found in the eyelids of six budgerigars (2.5%). Similar inclusions were simultaneously found in the pars ciliaris retinae (4, 1.7%), inner plexiform of retina (1, 0.4%) and anterior epithelium of the cornea (1, 0.4%). Other lesions such as candidial endophthalmitis, conjunctival cryptosporidiosis, corneal dystrophy, keratitis, corneal perforation and iridocyclitis, were occasional findings. PMID:18671000

  7. Evolution of ozone depletion on Antarctic and sub-Antarctic regions (1979-2012)

    NASA Astrophysics Data System (ADS)

    Diaz, S. B.; Paladini, A. A.; Deferrari, G. A.; Vrsalovic, J.

    2013-08-01

    At the middle eighties, strong stratospheric ozone depletion during spring was discovered over Antarctica. Since then, the scientific community has put large efforts in performing studies directed to evaluate the magnitude and consequences of this depletion and to take the necessary measures to revert the situation to the scenarios before 1970. In 1987, the Montreal Protocol established a list of ozone depleting products and faced out policies. As consequence of these restrictions on ozone depleting substances, the ozone layer should start to recover in the 21st century. In order to study the evolution of the Antarctic ozone depletion, we analyzed the ozone hole area and mass deficit and seasonal total ozone column (TOC) minimum. We also performed a seasonal and bi-monthly analysis for TOC time series (1979-2012), at twenty Antarctic and Sub-Antarctic stations. The number of days inside the vortex (TOC below 220DU) per season (September-December) and for September-October and November-December were analyzed, fitting the time series with a second degree polynomial According to this study, ozone hole area would have peaked between 2001 and 2002 (R=0.91, p<0.01), while the minimum TOC would have occurred between 2000 and 2001(R=0.91, p<0.01). Mass deficit is only provided since 2005 and it showed a decrease since then, although ot statistically significant as consequence of the short time series. From the 20 analyzed stations, 80% showed that the number of days per season inside the vortex peaked between 2000 and 2003 and for 55% of the stations the number of days inside the vortex for September-October peaked between 1999 and 2004.

  8. Effects of bird-feeding activities on the health of wild birds

    PubMed Central

    Wilcoxen, Travis E.; Horn, David J.; Hogan, Brianna M.; Hubble, Cody N.; Huber, Sarah J.; Flamm, Joseph; Knott, Madeline; Lundstrom, Lisa; Salik, Faaria; Wassenhove, Samantha J.; Wrobel, Elizabeth R.

    2015-01-01

    Among the most popular reasons that people feed wild birds is that they want to help birds. The extent to which supplemental food helps birds, however, is not well established. From spring 2011 to spring 2014, we examined how feeding of wild birds influences the health of individual birds at forested sites in central Illinois, USA. Specifically, we compared three forested sites where we provided supplemental food with three forested sites for which no supplemental food was available and monitored changes in the individual health of birds. In addition, we determined whether any changes in bird health had occurred after feeders had been removed from sites 10 months before. Generally, the individual health of birds improved with supplemental feeding, including increased antioxidant levels, reduced stress (heterophil-to-lymphocyte ratio) and more rapid feather growth. In some species, we also found improved body condition index scores and innate immune defense. The difference among sites was not present 10 months after feeders were removed, suggesting that the impact on health was indeed related to supplemental feeding. Potential negative effects of supplemental feeding were also found, including an increase in infectious disease prevalence among individual birds at forested sites where supplemental food was offered. Birds with clear signs of pathology showed deficits in most of the physiological metrics in which birds at feeder sites typically showed improved health condition. At the peak of prevalence of infectious disease, 8.3% of all birds at feeders exhibited symptoms of conjunctivitis, pox, dermal disease or cloacal disease. We found both positive and negative impacts of wild bird feeding, and that, in general, birds that had access to supplemental food were in better physiological condition. Moreover, the negative effects we found may be mitigated by hobbyists engaging in safer bird-feeding practices. PMID:27293740

  9. Assessment of bird response to the Migratory Bird Habitat Initiative using weather-surveillance radar

    USGS Publications Warehouse

    Sieges, Mason L.; Smolinsky, Jaclyn A.; Baldwin, Michael J.; Barrow, Wylie C.; Randall, Lori A.; Buler, Jeffrey J.

    2014-01-01

    In response to the Deepwater Horizon oil spill in spring 2010, the Natural Resources Conservation Service implemented the Migratory Bird Habitat Initiative (MBHI) to provide temporary wetland habitat for migrating and wintering waterfowl, shorebirds, and other birds along the northern Gulf of Mexico via managed flooding of agricultural lands. We used weather-surveillance radar to conduct broad regional assessments of bird response to MBHI activities within the Mississippi Alluvial Valley and the West Gulf Coastal Plain. Across both regions, birds responded positively to MBHI management by exhibiting greater relative bird densities within sites relative to pre-management conditions in prior years and relative to surrounding non-flooded agricultural lands. Bird density at MBHI sites was generally greatest during winter for both regions. Unusually high flooding in the years prior to implementation of the MBHI confounded detection of overall changes in remotely sensed soil wetness across sites. The magnitude of bird response at MBHI sites compared to prior years and to non-flooded agricultural lands was generally related to the surrounding landscape context: proximity to areas of high bird density, amount of forested wetlands, emergent marsh, non-flooded agriculture, or permanent open water. However, these relationships varied in strength and direction between regions and seasons, a finding which we attribute to differences in seasonal bird composition and broad regional differences in landscape configuration and composition. We detected greater increases in relative bird use at sites in closer proximity to areas of high bird density during winter in both regions. Additionally, bird density was greater during winter at sites with more emergent marsh in the surrounding landscape. Thus, bird use of managed wetlands could be maximized by enrolling lands located near areas of known bird concentration and within a mosaic of existing wetlands. Weather-radar observations

  10. Effects of bird-feeding activities on the health of wild birds.

    PubMed

    Wilcoxen, Travis E; Horn, David J; Hogan, Brianna M; Hubble, Cody N; Huber, Sarah J; Flamm, Joseph; Knott, Madeline; Lundstrom, Lisa; Salik, Faaria; Wassenhove, Samantha J; Wrobel, Elizabeth R

    2015-01-01

    Among the most popular reasons that people feed wild birds is that they want to help birds. The extent to which supplemental food helps birds, however, is not well established. From spring 2011 to spring 2014, we examined how feeding of wild birds influences the health of individual birds at forested sites in central Illinois, USA. Specifically, we compared three forested sites where we provided supplemental food with three forested sites for which no supplemental food was available and monitored changes in the individual health of birds. In addition, we determined whether any changes in bird health had occurred after feeders had been removed from sites 10 months before. Generally, the individual health of birds improved with supplemental feeding, including increased antioxidant levels, reduced stress (heterophil-to-lymphocyte ratio) and more rapid feather growth. In some species, we also found improved body condition index scores and innate immune defense. The difference among sites was not present 10 months after feeders were removed, suggesting that the impact on health was indeed related to supplemental feeding. Potential negative effects of supplemental feeding were also found, including an increase in infectious disease prevalence among individual birds at forested sites where supplemental food was offered. Birds with clear signs of pathology showed deficits in most of the physiological metrics in which birds at feeder sites typically showed improved health condition. At the peak of prevalence of infectious disease, 8.3% of all birds at feeders exhibited symptoms of conjunctivitis, pox, dermal disease or cloacal disease. We found both positive and negative impacts of wild bird feeding, and that, in general, birds that had access to supplemental food were in better physiological condition. Moreover, the negative effects we found may be mitigated by hobbyists engaging in safer bird-feeding practices. PMID:27293740

  11. Antarktis: Das CCAMLR-Übereinkommen (Convention on the Conservation of Antarctic Marine Living Resources) und die illegale Überfischung der südlichen Ozeane

    NASA Astrophysics Data System (ADS)

    Siegel, Volker

    1999-12-01

    The Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) was ratified in 1982. This Convention was established in the light of a rapidly developing krill fishery in the 1970’s. The objectives of the Convention are the rational use of marine living resources as well as the conservation of the resources and the marine ecosystem. Establishing the principle of the ecosystem approach has been rather progressive in fisheries conventions. From the bery beginning CCAMLR had to deal with problems of over-exploited fish stock from the unregulated fishery of pre-CCAMLR times. Antarctic cod and icefish stock were already heavily harvested or even showed signs of overfishing. Conservation measures and the closure of subareas for several years did not always lead to satisfactorily results. While some stock of icefish recovered to the extent, that a new fishery on a low level could be re-opened, other icefish stocks and especially Antarctic cod stocks have not recovered from this early depletion. A new dimension in the fishery developed in the mid 1990’s, when very conservative conservation measures were introduced for the Dissostichus (toothfish), but due to the high commercial value a large illegal fishery developed rapidly in the Convention area. One additional problem of managing the longline fishery for toothfish is the by-catch and incidental mortality of sea-birds, for which special measures were established to avoid sea-bird mortality. The compliance with the measures and the elimination of the illegal fishery require strong actions of the Commission, the political decision-making body of CCAMLR. A future challange for CCAMLR could be the potentially expanding krill fishery. In the understanding of a precautionary approach, the scientific body of CCAMLR has already started to collect biological data and develop management and monitoring models for this fishery.

  12. Estimation of Antarctic Sea Ice Thickness From Satellite Radar Altimetry

    NASA Astrophysics Data System (ADS)

    Potter, R. C. H.; Laxon, S. W.; Peacock, N.

    The spatial and temporal variability of Antarctic sea-ice extent and thickness are re- quired by the climate modelling community to understand the complex coupling be- tween sea ice and ocean-atmosphere. Recent investigations have provided estimates of Arctic sea ice thickness determined from satellite radar altimetry, which have been validated using Upward Looking Sonar data from submarines. In the present study, we aim to explore the potential for estimation of the thickness of Antarctic sea ice. In the boreal summer, the Arctic Ocean is pre-dominantly inhabited by old, multiyear sea-ice that may survive through each melt season and subsequently refreeze and in- crease in thickness under autumn cooling and winter growth. However, aside from the Weddell Sea, the Antarctic sea ice is subject to almost complete seasonal melt/freeze with the formation of pre-dominant first year ice. To estimate ice thickness from mea- surements of ice elevation it is necessary to establish the vertical origin of the radar echo's received over snow covered ice. Assuming reflection originates at the snow/ice interface, the ice freeboard can be estimated. The freeboard is converted to ice thick- ness using fixed densities for ice and seawater and a recently generated Antarctic Snow depth climatology. However, the developed altimetry techniques are designed for rela- tively thick Arctic sea ice and therefore may not be directly applicable to the relatively thin non-compacted first year Antarctic sea ice. In particular, snow loading owing to high precipitation rates is likely to be much larger compared to ice thickness. In ex- treme conditions this may lead to negative freeboard. Nevertheless, data on Antarctic ice thickness is even more sparse than the Arctic and hence information on thickness would be of significant value. We present preliminary results of Antarctic ice thickness estimates and validation using ULS data.

  13. [Medical and biological studies of Ukrainian scientists in Antarctic region].

    PubMed

    Moiseienko, Ie V

    2003-01-01

    People adaptation problem in Antarctic conditions, prophylactics of the desinchronostic disturbances, destability of psycho-emotion state, pathological manifestation of the heart-vessel system, tasks of regional waste influences on the people organism are not insolvable up to now and is the base of medical-biological researches. In accordance with the peculiarities of the geographical positions of Academician Vernadsky station and long period of staying in extremely conditions of Antarctic the medical-physiological researches will executed on the each stage. During the selection of candidates for the work at Ukrainian Antarctic station we studied new medico-biological criteria including genetic markers with aim to forecast antagonism functional state during wintering. At the period of staying in Antarctic in the conditions of season inversions and hour belts removals it will executed the researches of biorhythmological peculiarities of the psychophysiological function and heart-vessel system states, outer system of breathing and biochemistry indexes of people fluids. It was shown that the biggest part of disturbances in organisms functional system at the period of Antarctic winter has an ability to restoration after returning to homeland. However, disturbances in immunology system state are prolonged, harmful influence of solar radiation are revealed on the people sight, especially, when one use the not recommended lighting filters. With the purpose of prophylactic of desynchronic disturbances, which was find after wintering at the more then 90% expedition personnel, it was worked out an non invasion methods of correction by using the individual polychromatic influence on organism. It is studied the teleconnection results of long period staying of expedition staff in Antarctic. It was established, that Ukrainian members of expedition have the fixed number of radionuclids of Cesium in organism. After staying in Antarctic radionuclids of Cesium in organism do not

  14. Breeding Bird Survey and bird banding data: Applications to raptor research and management

    USGS Publications Warehouse

    Sauer, J.R.; Droege, S.; Bystrak, D.

    1991-01-01

    The Breeding Bird Survey (BBS) and Bird Banding Laboratory (BBL) are sources of information for raptor biologists. The BBS has been conducted each year since 1966 in the United States and Canada; historical bird banding records extend back to the early 20th century. BBS data can be used to document population trends and breeding distributions of many bird species. Banding data are generally collected for specific and local studies of bird populations or behavior. Past use of these data has been limited by their volume and relative inaccessibility. In this paper, we present an overview of BBS and BBL raptor data and their uses, limitations and availability.

  15. Control of Bird Vetch in Alaska

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bird vetch is a perennial Eurasian plant which, unlike many exotic weed species, can invade low fertility areas that have not been disturbed. It also is found in pastures, woodland, and tall forb communities. Bird vetch is expanding along Alaska roadsides, in urbanized areas, and in low density aspe...

  16. 14 CFR 33.76 - Bird ingestion.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bird ingestion. 33.76 Section 33.76... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.76 Bird ingestion. (a... takeoff thrust or power. (2) The engine inlet throat area as used in this section to determine the...

  17. 14 CFR 33.76 - Bird ingestion.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bird ingestion. 33.76 Section 33.76... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.76 Bird ingestion. (a... takeoff thrust or power. (2) The engine inlet throat area as used in this section to determine the...

  18. 14 CFR 33.76 - Bird ingestion.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bird ingestion. 33.76 Section 33.76... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.76 Bird ingestion. (a... takeoff thrust or power. (2) The engine inlet throat area as used in this section to determine the...

  19. Endogenous timing factors in bird migration

    NASA Technical Reports Server (NTRS)

    Gwinner, E. G.

    1972-01-01

    Several species of warbler birds were observed in an effort to determine what initiates and terminates migration. Environmental and endogenous timing mechanisms were analyzed. The results indicate that endogenous stimuli are dominant factors for bird migration especially for long distances. It was concluded that environmental factors act as an assist mechanism.

  20. 21 CFR 1240.65 - Psittacine birds.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) REGULATIONS... traffic any psittacine bird unless the shipment is accompanied by a permit from the State health... finds that psittacine birds or human beings in any area are infected with psittacosis and there is...

  1. 21 CFR 1240.65 - Psittacine birds.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) REGULATIONS... traffic any psittacine bird unless the shipment is accompanied by a permit from the State health... finds that psittacine birds or human beings in any area are infected with psittacosis and there is...

  2. Supplementary feeding restructures urban bird communities

    PubMed Central

    Galbraith, Josie A.; Jones, Darryl N.; Stanley, Margaret C.

    2015-01-01

    Food availability is a primary driver of avian population regulation. However, few studies have considered the effects of what is essentially a massive supplementary feeding experiment: the practice of wild bird feeding. Bird feeding has been posited as an important factor influencing the structure of bird communities, especially in urban areas, although experimental evidence to support this is almost entirely lacking. We carried out an 18-mo experimental feeding study at 23 residential properties to investigate the effects of bird feeding on local urban avian assemblages. Our feeding regime was based on predominant urban feeding practices in our region. We used monthly bird surveys to compare avian community composition, species richness, and the densities of local species at feeding and nonfeeding properties. Avian community structure diverged at feeding properties and five of the commonest garden bird species were affected by the experimental feeding regime. Introduced birds particularly benefitted, with dramatic increases observed in the abundances of house sparrow (Passer domesticus) and spotted dove (Streptopelia chinensis) in particular. We also found evidence of a negative effect on the abundance of a native insectivore, the grey warbler (Gerygone igata). Almost all of the observed changes did not persist once feeding had ceased. Our study directly demonstrates that the human pastime of bird feeding substantially contributes to the structure of avian community in urban areas, potentially altering the balance between native and introduced species. PMID:25941361

  3. An integrative approach to understanding bird origins.

    PubMed

    Xu, Xing; Zhou, Zhonghe; Dudley, Robert; Mackem, Susan; Chuong, Cheng-Ming; Erickson, Gregory M; Varricchio, David J

    2014-12-12

    Recent discoveries of spectacular dinosaur fossils overwhelmingly support the hypothesis that birds are descended from maniraptoran theropod dinosaurs, and furthermore, demonstrate that distinctive bird characteristics such as feathers, flight, endothermic physiology, unique strategies for reproduction and growth, and a novel pulmonary system originated among Mesozoic terrestrial dinosaurs. The transition from ground-living to flight-capable theropod dinosaurs now probably represents one of the best-documented major evolutionary transitions in life history. Recent studies in developmental biology and other disciplines provide additional insights into how bird characteristics originated and evolved. The iconic features of extant birds for the most part evolved in a gradual and stepwise fashion throughout archosaur evolution. However, new data also highlight occasional bursts of morphological novelty at certain stages particularly close to the origin of birds and an unavoidable complex, mosaic evolutionary distribution of major bird characteristics on the theropod tree. Research into bird origins provides a premier example of how paleontological and neontological data can interact to reveal the complexity of major innovations, to answer key evolutionary questions, and to lead to new research directions. A better understanding of bird origins requires multifaceted and integrative approaches, yet fossils necessarily provide the final test of any evolutionary model. PMID:25504729

  4. Evolution: a rapid flight towards birds.

    PubMed

    Ksepka, Daniel T

    2014-11-01

    Remarkable feathered dinosaur fossils have blurred the lines between early birds and their non-avian dinosaur relatives. Rapid skeletal evolution and decreasing body size along one particular lineage of theropod dinosaurs paved the way for the spectacular radiation of birds. PMID:25517372

  5. 14 CFR 33.76 - Bird ingestion.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Bird ingestion. 33.76 Section 33.76... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.76 Bird ingestion. (a... takeoff thrust or power. (2) The engine inlet throat area as used in this section to determine the...

  6. Ability of Slovakian Pupils to Identify Birds

    ERIC Educational Resources Information Center

    Prokop, Pavol; Rodak, Rastislav

    2009-01-01

    A pupil's ability to identify common organisms is necessary for acquiring further knowledge of biology. We investigated how pupils were able to identify 25 bird species following their song, growth habits, or both features presented simultaneously. Just about 19% of birds were successfully identified by song, about 39% by growth habit, and 45% of…

  7. 14 CFR 33.76 - Bird ingestion.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bird ingestion. 33.76 Section 33.76... STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.76 Bird ingestion. (a... takeoff thrust or power. (2) The engine inlet throat area as used in this section to determine the...

  8. Fernbank Forest Birds in the Summer.

    ERIC Educational Resources Information Center

    Schmalz, Georgann

    1991-01-01

    Provided is a listing of the common nesting birds and the neotropical migrant birds with nesting records in the approximate 65 acres of Fernbank Forest which is a preserve of mature urban hardwoods and pines within 10 miles of downtown Atlanta and a relic of what was once a large, uninterrupted tract of the Piedmont forest. (JJK)

  9. The Origin and Diversification of Birds.

    PubMed

    Brusatte, Stephen L; O'Connor, Jingmai K; Jarvis, Erich D

    2015-10-01

    Birds are one of the most recognizable and diverse groups of modern vertebrates. Over the past two decades, a wealth of new fossil discoveries and phylogenetic and macroevolutionary studies has transformed our understanding of how birds originated and became so successful. Birds evolved from theropod dinosaurs during the Jurassic (around 165-150 million years ago) and their classic small, lightweight, feathered, and winged body plan was pieced together gradually over tens of millions of years of evolution rather than in one burst of innovation. Early birds diversified throughout the Jurassic and Cretaceous, becoming capable fliers with supercharged growth rates, but were decimated at the end-Cretaceous extinction alongside their close dinosaurian relatives. After the mass extinction, modern birds (members of the avian crown group) explosively diversified, culminating in more than 10,000 species distributed worldwide today. PMID:26439352

  10. The safety band of Antarctic ice shelves

    NASA Astrophysics Data System (ADS)

    Fürst, Johannes Jakob; Durand, Gaël; Gillet-Chaulet, Fabien; Tavard, Laure; Rankl, Melanie; Braun, Matthias; Gagliardini, Olivier

    2016-05-01

    The floating ice shelves along the seaboard of the Antarctic ice sheet restrain the outflow of upstream grounded ice. Removal of these ice shelves, as shown by past ice-shelf recession and break-up, accelerates the outflow, which adds to sea-level rise. A key question in predicting future outflow is to quantify the extent of calving that might precondition other dynamic consequences and lead to loss of ice-shelf restraint. Here we delineate frontal areas that we label as `passive shelf ice’ and that can be removed without major dynamic implications, with contrasting results across the continent. The ice shelves in the Amundsen and Bellingshausen seas have limited or almost no `passive’ portion, which implies that further retreat of current ice-shelf fronts will yield important dynamic consequences. This region is particularly vulnerable as ice shelves have been thinning at high rates for two decades and as upstream grounded ice rests on a backward sloping bed, a precondition to marine ice-sheet instability. In contrast to these ice shelves, Larsen C Ice Shelf, in the Weddell Sea, exhibits a large `passive’ frontal area, suggesting that the imminent calving of a vast tabular iceberg will be unlikely to instantly produce much dynamic change.

  11. Blowing Snow Over the Antarctic Plateau

    NASA Technical Reports Server (NTRS)

    Mahesh, Ashwin; Eager, Rebecca; Campbell, James R.; Spinhirne, James D.

    2002-01-01

    Studies of blowing snow over Antarctica have been limited greatly by the remoteness and harsh conditions of the region. Space-based observations are also of lesser value than elsewhere, given the similarities between ice clouds and snow-covered surfaces, both at infrared and visible wavelengths. It is only in recent years that routine ground-based observation programs have acquired sufficient data to overcome the gap in our understanding of surface blowing snow. In this paper, observations of blowing snow from visual observers' records as well as ground-based spectral and lidar programs at South Pole station are analyzed to obtain the first climatology of blowing snow over the Antarctic plateau. Occurrence frequencies, correlation with wind direction and speed, typical layer heights, as well as optical depths are determined. Blowing snow is seen in roughly one third of the visual observations and occurs under a narrow range of wind directions. The near-surface layers typically a few hundred meters thick emit radiances similar to those from thin clouds. Because blowing snow remains close to the surface and is frequently present, it will produce small biases in space-borne altimetry; these must be properly estimated and corrected.

  12. Sei whale sounds recorded in the Antarctic.

    PubMed

    McDonald, Mark A; Hildebrand, John A; Wiggins, Sean M; Thiele, Deborah; Glasgow, Deb; Moore, Sue E

    2005-12-01

    Sei whales are the least well known acoustically of all the rorquals, with only two brief descriptions of their calls previously reported. Recordings of low-frequency tonal and frequency swept calls were made near a group of four or five sei whales in waters west of the Antarctic Peninsula on 19 February 2003. These whales also produced broadband sounds which can be described as growls or whooshes. Many of the tonal and frequency swept calls (30 out of 68) consist of multiple parts with a frequency step between the two parts, this being the most unique characteristic of the calls, allowing them to be distinguished from the calls of other whale species. The average duration of the tonal calls is 0.45 +/- 0.3 s and the average frequency is 433 +/- 192 Hz. Using a calibrated seafloor recorder to determine the absolute calibration of a sonobuoy system, the maximum source level of the tonal calls was 156 +/- 3.6 dB re 1 microPa at 1 m. Each call had different character and there was no temporal pattern in the calling. PMID:16419837

  13. Sei whale sounds recorded in the Antarctic

    NASA Astrophysics Data System (ADS)

    McDonald, Mark A.; Hildebrand, John A.; Wiggins, Sean M.; Thiele, Deborah; Glasgow, Deb; Moore, Sue E.

    2005-12-01

    Sei whales are the least well known acoustically of all the rorquals, with only two brief descriptions of their calls previously reported. Recordings of low-frequency tonal and frequency swept calls were made near a group of four or five sei whales in waters west of the Antarctic Peninsula on 19 February 2003. These whales also produced broadband sounds which can be described as growls or whooshes. Many of the tonal and frequency swept calls (30 out of 68) consist of multiple parts with a frequency step between the two parts, this being the most unique characteristic of the calls, allowing them to be distinguished from the calls of other whale species. The average duration of the tonal calls is 0.45+/-0.3 s and the average frequency is 433+/-192 Hz. Using a calibrated seafloor recorder to determine the absolute calibration of a sonobuoy system, the maximum source level of the tonal calls was 156+/-3.6 dB re 1 μPa at 1 m. Each call had different character and there was no temporal pattern in the calling.

  14. Responses of Antarctic Oscillation to global warming

    NASA Astrophysics Data System (ADS)

    Feng, S.

    2015-12-01

    The Antarctic Oscillation (AAO) is the major annular mode dominates the spatiotemporal variability of the atmospheric circulation in the Southern Hemisphere. This study examined the sensitivity of AAO to future warming by analyzing the outputs of 34 state-of-the-art climate models participating in phase 5 of the Coupled Model Intercomparion Project (CMIP5). The model simulations include the stabilized (RCP4.5) and business as usual (RCP8.5) scenarios as well as the idealized 1% per year increase in atmospheric CO2 to quadrupling (1pctCO2) and an instantaneous quadrupling of CO2 (abrupt4xCO2). We show that the CMIP5 models on average simulate increases in the AAO in every season by 2100 under the RCP4.5 and RCP8.5 scenarios. However, due to the impacts of ozone, aerosol and land use changes, the amplitudes of the projected changes in AAO to future climate scenarios are quit different on different seasons. After the impact of ozone, aerosol and land use changes were removed; it was found that the impact of greenhouse gases (GHGs) on AAO is similar on all seasons. The increases of AAO are accelerating following the increase of GHGs. Our results are also consistent with the simulations of 1pctCO2 and abrupt4xCO2.

  15. Antarctic Yeasts: Biodiversity and Potential Applications

    NASA Astrophysics Data System (ADS)

    Shivaji, S.; Prasad, G. S.

    This review is an attempt in cataloguing the diversity of yeasts in Antarctica, highlight their biotechnological potential and understand the basis of adaptation to low temperature. As of now several psychrophilic and psychrotolerant yeasts from Antarctic soils and marine waters have been characterized with respect to their growth characteristics, ecological distribution and taxonomic significance. Interestingly most of these species belonged to basidiomycetous yeasts which as a group are known for their ability to circumvent and survive under stress conditions. Simultaneously their possible role as work horses in the biotechnological industry was recognized due to their ability to produce novel enzymes and biomolecules such as agents for the breakdown of xenobiotics, and novel pharmaceutical chemi cals. The high activity of psychrophilic enzymes at low and moderate temperatures offers potential economic benefits. As of now lipases from Pseudozyma antarctica have been extensively studied to understand their unique thermal stability at 90°C and also because of its use in the pharmaceutical, agriculture, food, cosmetics and chemical industry. A few of the other enzymes which have been studied include extracellular alpha-amylase and glucoamylase from the yeast Pseudozyma antarctica (Candida antarctica), an extra-cellular protease from Cryptococcus humicola, an aspartyl proteinase from Cryptococcus humicola, a novel extracellular subtilase from Leucosporidium antarcticum, and a xylanase from Cryptococcus adeliensis

  16. Arctic and Antarctic cells in the troposphere

    NASA Astrophysics Data System (ADS)

    Qian, Weihong; Wu, Kaijun; Liang, Haoyuan

    2016-07-01

    The three-cell model, including the Hadley, Ferrel, and Polar cells in each of two hemispheres, has been accepted for a long time and the strongest Hadley cell has been used to study the climate change in recent years. However, two questions, why the upper level flow of Ferrel cell does not match observations and how many cells exist in the two polar regions, still exist. Using three different reanalysis datasets for the last 30 years, this paper showed that there might be an additional cell in each of two polar regions. The analyses of meridional-vertical section streamline (MSS), meridional-mass stream function (MSF), and climatic vertical velocity provide some evidences to support the existence of the new Arctic and Antarctic cells located in the troposphere. Thus, an eight-cell model in the global troposphere is proposed in this study. The maximum intensity of the Hadley cell in the boreal winter indicated by MSF in the Northern Hemisphere (NH) is stronger than that of the Ferrel cell for about 4.8 times, so the upper level northeasterly wind of Ferrel cell is too weak to be detected when compared with the stronger southwesterly wind of the Hadley cell.

  17. Recent changes in Antarctic Sea Ice.

    PubMed

    Turner, John; Hosking, J Scott; Bracegirdle, Thomas J; Marshall, Gareth J; Phillips, Tony

    2015-07-13

    In contrast to the Arctic, total sea ice extent (SIE) across the Southern Ocean has increased since the late 1970s, with the annual mean increasing at a rate of 186×10(3) km(2) per decade (1.5% per decade; p<0.01) for 1979-2013. However, this overall increase masks larger regional variations, most notably an increase (decrease) over the Ross (Amundsen-Bellingshausen) Sea. Sea ice variability results from changes in atmospheric and oceanic conditions, although the former is thought to be more significant, since there is a high correlation between anomalies in the ice concentration and the near-surface wind field. The Southern Ocean SIE trend is dominated by the increase in the Ross Sea sector, where the SIE is significantly correlated with the depth of the Amundsen Sea Low (ASL), which has deepened since 1979. The depth of the ASL is influenced by a number of external factors, including tropical sea surface temperatures, but the low also has a large locally driven intrinsic variability, suggesting that SIE in these areas is especially variable. Many of the current generation of coupled climate models have difficulty in simulating sea ice. However, output from the better-performing IPCC CMIP5 models suggests that the recent increase in Antarctic SIE may be within the bounds of intrinsic/internal variability. PMID:26032320

  18. Meridional displacement of the Antarctic Circumpolar Current.

    PubMed

    Gille, Sarah T

    2014-07-13

    Observed long-term warming trends in the Southern Ocean have been interpreted as a sign of increased poleward eddy heat transport or of a poleward displacement of the entire Antarctic Circumpolar Current (ACC) frontal system. The two-decade-long record from satellite altimetry is an important source of information for evaluating the mechanisms governing these trends. While several recent studies have used sea surface height contours to index ACC frontal displacements, here altimeter data are instead used to track the latitude of mean ACC transport. Altimetric height contours indicate a poleward trend, regardless of whether they are associated with ACC fronts. The zonally averaged transport latitude index shows no long-term trend, implying that ACC meridional shifts determined from sea surface height might be associated with large-scale changes in sea surface height more than with localized shifts in frontal positions. The transport latitude index is weakly sensitive to the Southern Annular Mode, but is uncorrelated with El Niño/Southern Oscillation. PMID:24891396

  19. Automated detection of Antarctic blue whale calls.

    PubMed

    Socheleau, Francois-Xavier; Leroy, Emmanuelle; Pecci, Andres Carvallo; Samaran, Flore; Bonnel, Julien; Royer, Jean-Yves

    2015-11-01

    This paper addresses the problem of automated detection of Z-calls emitted by Antarctic blue whales (B. m. intermedia). The proposed solution is based on a subspace detector of sigmoidal-frequency signals with unknown time-varying amplitude. This detection strategy takes into account frequency variations of blue whale calls as well as the presence of other transient sounds that can interfere with Z-calls (such as airguns or other whale calls). The proposed method has been tested on more than 105 h of acoustic data containing about 2200 Z-calls (as found by an experienced human operator). This method is shown to have a correct-detection rate of up to more than 15% better than the extensible bioacoustic tool package, a spectrogram-based correlation detector commonly used to study blue whales. Because the proposed method relies on subspace detection, it does not suffer from some drawbacks of correlation-based detectors. In particular, it does not require the choice of an a priori fixed and subjective template. The analytic expression of the detection performance is also derived, which provides crucial information for higher level analyses such as animal density estimation from acoustic data. Finally, the detection threshold automatically adapts to the soundscape in order not to violate a user-specified false alarm rate. PMID:26627784

  20. Koronis asteroid dust within Antarctic ice

    NASA Astrophysics Data System (ADS)

    Genge, Matthew J.

    2008-09-01

    Here I report the first discovery of large numbers of ordinarychondrite-derived micro-meteorites (MMs) recovered fromAntarctic ice. Ordinary chondrite-derived MMs comprise70% coarse-grained igneous particles and are identified on thebasis of their distribution of petrologic types, accessory mineralogy,and minor element compositions, all of which are very similarto those of millimeter-sized igneous objects known as chondrules,from ordinary chondrites, and largely distinct from those ofother meteorite groups. The majority of ordinary chondrite-derivedMMs are unequilibrated materials; however, 15% are equilibrated,indicating parent body metamorphism, and have compositions consistentwith both H (high iron) and L (low iron) chondrites. The totalabundance of ordinary chondrite-derived MMs of ~18% issimilar to predictions by numerical calculations for the abundanceof dust generated by the recent breakup of the Karin group asteroidsof the Koronis asteroid family, suggesting that these asteroidsare the main source of the particles. These MMs represent thefirst to be associated with a known asteroid and imply thatthe Karin group progenitor asteroid was a rubble-pile asteroidthat sampled different depths within the original internallymetamorphosed Koronis parent body.

  1. The permeability of the Antarctic vortex edge

    NASA Technical Reports Server (NTRS)

    Chen, Ping

    1994-01-01

    Mixing and cross-vortex mass transport along isentropic surfaces in the lower stratosphere are investigated with a 'contour advection' technique and a semi-Lagrangian transport model for the Antarctic winter of 1993 using analyzed winds from the United Kingdom Meteorological Office data assimilation system. Results from the 'contour advection' technique show that at the vortex edge there exists a potential vorticity (PV) contour that has the smallest lengthening rate. This PV contour is referred to as the 'line of separation' because it essentially separates the inner and outer vortex. The average e-folding time for the lengthening of the 'line of separation' increases monotonically with altitude, ranging from about 7 days on the 350 K isentropic surface to about 105 days on the 500 K isentropic surface. The results also suggest the existence of a transition layer around the 400 K isentropic surface, above which the vortex is nearly completely isolated from the midlatitudes and below which the vortex is less isolated. Results from a semi-Lagrangian transport model with an idealized tracer initially inside the inner vortex show that at 425 K and above virtually no tracer is transported out of the vortex during a 40-day integration starting from July 21, 1993. At 400 K and below a small amount of the tracer is transported out of the vortex while the bulk of the tracer remains confined within the inner vortex.

  2. Meridional displacement of the Antarctic Circumpolar Current

    PubMed Central

    Gille, Sarah T.

    2014-01-01

    Observed long-term warming trends in the Southern Ocean have been interpreted as a sign of increased poleward eddy heat transport or of a poleward displacement of the entire Antarctic Circumpolar Current (ACC) frontal system. The two-decade-long record from satellite altimetry is an important source of information for evaluating the mechanisms governing these trends. While several recent studies have used sea surface height contours to index ACC frontal displacements, here altimeter data are instead used to track the latitude of mean ACC transport. Altimetric height contours indicate a poleward trend, regardless of whether they are associated with ACC fronts. The zonally averaged transport latitude index shows no long-term trend, implying that ACC meridional shifts determined from sea surface height might be associated with large-scale changes in sea surface height more than with localized shifts in frontal positions. The transport latitude index is weakly sensitive to the Southern Annular Mode, but is uncorrelated with El Niño/Southern Oscillation. PMID:24891396

  3. Contribution of enhanced Antarctic Bottom Water formation to Antarctic warm events and millennial-scale atmospheric CO2 increase

    NASA Astrophysics Data System (ADS)

    Menviel, L.; Spence, P.; England, M. H.

    2015-03-01

    During Marine Isotope Stage 3, the Atlantic Meridional Overturning Circulation (AMOC) weakened significantly on a millennial time-scale leading to Greenland stadials. Ice core records reveal that each Greenland stadial is associated with a warming over Antarctica, so-called Antarctic Isotope Maximum (AIM), and that atmospheric CO2 increases with Antarctic temperature during the long Greenland stadials. Here we perform transient simulations spanning the period 50-34 ka B.P. with two Earth System Models (LOVECLIM and the UVic ESCM) to understand the possible link between changes in the AMOC, changes in high latitude Southern Hemispheric climate and evolution of atmospheric CO2. We find that oceanic carbon releases due to the AMOC resumption during stadial/interstadial transitions lead to an atmospheric CO2 increase. However, the atmospheric CO2 increases observed during the first parts of AIM12 (∼47.6 ka B.P.) and AIM8 (∼39.8 ka B.P.) occur during periods of weak AMOC (HS5 and HS4 respectively) and could instead be explained by enhanced Antarctic Bottom Water transport. Enhanced Antarctic Bottom Water formation is shown to effectively ventilate the deep Pacific carbon and lead to CO2 outgassing into the atmosphere. In addition, changes in the AMOC alone are not sufficient to explain the largest Antarctic Isotope Maxima (namely AIM12 and AIM8). Stronger formation of Antarctic Bottom Water during AIM12 and AIM8 would enhance the southern high latitude warming and lead to a better agreement with high southern latitude paleoproxy records. The robustness of this southern warming response is tested using an eddy-permitting coupled ocean sea-ice model. We show that stronger Antarctic Bottom Water formation contributes to Southern Ocean surface warming by increasing the Southern Ocean meridional heat transport.

  4. Prospects for surviving climate change in Antarctic aquatic species

    PubMed Central

    Peck, Lloyd S

    2005-01-01

    Maritime Antarctic freshwater habitats are amongst the fastest changing environments on Earth. Temperatures have risen around 1°C and ice cover has dramatically decreased in 15 years. Few animal species inhabit these sites, but the fairy shrimp Branchinecta gaini typifies those that do. This species survives up to 25°C daily temperature fluctuations in summer and passes winter as eggs at temperatures down to -25°C. Its annual temperature envelope is, therefore around 50°C. This is typical of Antarctic terrestrial species, which exhibit great physiological flexibility in coping with temperature fluctuations. The rapidly changing conditions in the Maritime Antarctic are enhancing fitness in these species by increasing the time available for feeding, growth and reproduction, as well as increasing productivity in lakes. The future problem these animals face is via displacement by alien species from lower latitudes. Such invasions are now well documented from sub-Antarctic sites. In contrast the marine Antarctic environment has very stable temperatures. However, seasonality is intense with very short summers and long winter periods of low to no algal productivity. Marine animals grow slowly, have long generation times, low metabolic rates and low levels of activity. They also die at temperatures between +5°C and +10°C. Failure of oxygen supply mechanisms and loss of aerobic scope defines upper temperature limits. As temperature rises, their ability to perform work declines rapidly before lethal limits are reached, such that 50% of populations of clams and limpets cannot perform essential activities at 2–3°C, and all scallops are incapable of swimming at 2°C. Currently there is little evidence of temperature change in Antarctic marine sites. Models predict average global sea temperatures will rise by around 2°C by 2100. Such a rise would take many Antarctic marine animals beyond their survival limits. Animals have 3 mechanisms for coping with change: they can

  5. A polar system of intercontinental bird migration.

    PubMed

    Alerstam, Thomas; Bäckman, Johan; Gudmundsson, Gudmundur A; Hedenström, Anders; Henningsson, Sara S; Karlsson, Håkan; Rosén, Mikael; Strandberg, Roine

    2007-10-22

    Studies of bird migration in the Beringia region of Alaska and eastern Siberia are of special interest for revealing the importance of bird migration between Eurasia and North America, for evaluating orientation principles used by the birds at polar latitudes and for understanding the evolutionary implications of intercontinental migratory connectivity among birds as well as their parasites. We used tracking radar placed onboard the ice-breaker Oden to register bird migratory flights from 30 July to 19 August 2005 and we encountered extensive bird migration in the whole Beringia range from latitude 64 degrees N in Bering Strait up to latitude 75 degrees N far north of Wrangel Island, with eastward flights making up 79% of all track directions. The results from Beringia were used in combination with radar studies from the Arctic Ocean north of Siberia and in the Beaufort Sea to make a reconstruction of a major Siberian-American bird migration system in a wide Arctic sector between longitudes 110 degrees E and 130 degrees W, spanning one-third of the entire circumpolar circle. This system was estimated to involve more than 2 million birds, mainly shorebirds, terns and skuas, flying across the Arctic Ocean at mean altitudes exceeding 1 km (maximum altitudes 3-5 km). Great circle orientation provided a significantly better fit with observed flight directions at 20 different sites and areas than constant geographical compass orientation. The long flights over the sea spanned 40-80 degrees of longitude, corresponding to distances and durations of 1400-2600 km and 26-48 hours, respectively. The birds continued from this eastward migration system over the Arctic Ocean into several different flyway systems at the American continents and the Pacific Ocean. Minimization of distances between tundra breeding sectors and northerly stopover sites, in combination with the Beringia glacial refugium and colonization history, seemed to be important for the evolution of this major

  6. Complex Geodetic Research in Ukrainian Antarctic Station "Academician Vernadsky" (Years 2002 - 2005, 2013-2014)

    NASA Astrophysics Data System (ADS)

    Tretyak, Kornyliy; Hlotov, Volodymyr; Holubinka, Yuriy; Marusazh, Khrystyna

    2016-06-01

    In this paper is given an information about complex geodetic research in Ukrainian Antarctic station "Academician Vernadsky". Research were carried by Lviv polytechnic scientists, during Antarctic expeditions in years 2002 - 2005, 2013, 2014. Main objectives of the studies were: (a) study of the islands glaciers surface volumes changes in Antarctic archipelago and Antarctic Peninsula using terestrial laser scaning and digital terrestrial stereophotogrammetry survey; (b) investigation of Penola strain tectonic fault, using the results of precise GNSS observations.

  7. An Antarctic Time Capsule: Compiling and Hosting 60 years of USGS Antarctic Aerial Photography

    NASA Astrophysics Data System (ADS)

    Niebuhr, S.; Child, S.; Porter, C.; Herried, B.; Morin, P. J.

    2010-12-01

    The Antarctic Geospatial Information Center (AGIC) and the US Geologic Survey (USGS) collaborated to scan, archive, and make available 330,000 trimetrogon aerial (TMA) photos from 1860 flight lines taken over Antarctica from 1946 to 2000. Staff at USGS scanned them at 400 dpi and 1024 dpi resolution. To geolocate them, AGIC digitized the flight line maps, added relevant metadata including flight line altitude, camera type, and focal length, and approximated geographic centers for each photo. Both USGS and AGIC host the medium resolution air photos online, and are adding high resolution scans as they become available. The development of these metadata allowed AGIC to create a web-based flight line and aerial photo browsing application to facilitate the searching process. The application allows the user to browse through air photos and flight lines by location with links to full resolution preview images and to image downloads. AGIC has also orthorectified selected photos of facilities and areas of high scientific interest and are making them available online. This includes a time series showing significant change in several glaciers and lakes in the McMurdo Dry Valleys over 50 years and a series illustrating how McMurdo Station has changed. For the first time, this collection of historical imagery over a swiftly changing continent are readily available to the Antarctic scientific community (www.agic.umn.edu/imagery/aerial).

  8. The spatial extent and dynamics of the Antarctic Cold Reversal

    NASA Astrophysics Data System (ADS)

    Pedro, Joel B.; Bostock, Helen C.; Bitz, Cecilia M.; He, Feng; Vandergoes, Marcus J.; Steig, Eric J.; Chase, Brian M.; Krause, Claire E.; Rasmussen, Sune O.; Markle, Bradley R.; Cortese, Giuseppe

    2016-01-01

    Antarctic ice cores show that a millennial-scale cooling event, the Antarctic Cold Reversal (14,700 to 13,000 years ago), interrupted the last deglaciation. The Antarctic Cold Reversal coincides with the Bølling-Allerød warm stage in the North Atlantic, providing an example of the inter-hemispheric coupling of abrupt climate change generally referred to as the bipolar seesaw. However, the ocean-atmosphere dynamics governing this coupling are debated. Here we examine the extent and expression of the Antarctic Cold Reversal in the Southern Hemisphere using a synthesis of 84 palaeoclimate records. We find that the cooling is strongest in the South Atlantic and all regions south of 40° S. At the same time, the terrestrial tropics and subtropics show abrupt hydrologic variations that are significantly correlated with North Atlantic climate changes. Our transient global climate model simulations indicate that the observed extent of Antarctic Cold Reversal cooling can be explained by enhanced northward ocean heat transport from the South to North Atlantic, amplified by the expansion and thickening of sea ice in the Southern Ocean. The hydrologic variations at lower latitudes result from an opposing enhancement of southward heat transport in the atmosphere mediated by the Hadley circulation. Our findings reconcile previous arguments about the relative dominance of ocean and atmospheric heat transports in inter-hemispheric coupling, demonstrating that the spatial pattern of past millennial-scale climate change reflects the superposition of both.

  9. Was the Antarctic Circumpolar Current initiated by the Cenozoic cooling?

    NASA Astrophysics Data System (ADS)

    Lefebvre, Vincent; Donnadieu, Yannick; Sepulchre, Pierre; Swingedouw, Didier; Zhang, Zongshi

    2013-04-01

    Growth of Antarctic ice sheet during the Cenozoic 34 million years ago appears as a potential tipping point in the long-term cooling trend that began 50 Ma ago. For decades, the onset of the Antarctic Circumpolar Current (ACC) following the opening of the Drake Passage and of the Tasman Seaway has been suggested as the main driver of the continental-scale Antarctic glaciation. However, recent modelling works emphasized that the Eocene/Oligocene atmospheric carbon dioxide (CO2) lowering could be the primary forcing of the Antarctic glaciation, questioning the ACC theory. Here, we used a fully coupled atmosphere-ocean model (FOAM) with a mid-Oligocene geography to depict the response of the ACC to changes in the atmospheric CO2 level. Our results suggest that the opening of southern oceanic gateways does not trigger the onset of the ACC for CO2 typical of the late Eocene (> 840 ppm). We find that a cooler background climatic state such as the one prevalent at the end of the Oligocene is required to simulate a well-developed ACC. In this cold configuration, the intensified sea-ice development around Antarctica and the resulting brine formation lead to a strong latitudinal density gradient in the Southern Ocean favouring the compensation of the Ekman transport, and consequently the ACC. Our results imply that the ACC was initiated after the onset of the Antarctic ice sheet growth, acting as a feedback rather than as a driver of the global cooling.

  10. Antarctic ecosystems as models for extraterrestrial surface habitats

    NASA Astrophysics Data System (ADS)

    Wynn-Williams, D. D.; Edwards, H. G. M.

    2000-09-01

    Surface habitats in Antarctic deserts are near the limits of life on Earth and resemble those hypothesized for early Mars. Cyanobacteria dominate the transient riverbeds, stromatolitic sediments in ice-covered lakes, and endolithic communities in translucent rock. There is still no direct evidence of photosynthetic life on early Mars, but cyanobacteria are amongst the earliest microbes detectable in the fossil record for analogous habitats on Earth. Key biomolecules persist in Antarctic microbial habitats, even after extinction by excessive low temperatures, desiccation and UV-B stress within the Ozone Hole. Pigments (or their fossil residues), such as chlorophyll and the UV-protectants scytonemin, carotene and quinones, are good biomarkers. To show not only their presence but also their micro-spatial distribution in situ, we describe the use of FT-Raman spectroscopy with 1064 nm excitation to avoid autofluorescence from the pigments. We report not only the diversity of biomolecules that we have diagnosed from their unique Raman spectra of Antarctic cyanobacterial communities, but also their functional stratification in endolithic communities. Our analyses of Antarctic habitats show the potential of this remote, non-intrusive technique to probe for buried biomolecules on future Mars missions and in Antarctic Lake Vostok, >4 km beneath the Central Ice Sheet, with implications for the putative analogous sub-ice ocean on Europa.

  11. The Antarctic ozone depletion caused by Erebus volcano gas emissions

    NASA Astrophysics Data System (ADS)

    Zuev, V. V.; Zueva, N. E.; Savelieva, E. S.; Gerasimov, V. V.

    2015-12-01

    Heterogeneous chemical reactions releasing photochemically active molecular chlorine play a key role in Antarctic stratospheric ozone destruction, resulting in the Antarctic ozone hole. Hydrogen chloride (HCl) is one of the principal components in these reactions on the surfaces of polar stratospheric clouds (PSCs). PSCs form during polar nights at extremely low temperatures (lower than -78 °C) mainly on sulfuric acid (H2SO4) aerosols, acting as condensation nuclei and formed from sulfur dioxide (SO2). However, the cause of HCl and H2SO4 high concentrations in the Antarctic stratosphere, leading to considerable springtime ozone depletion, is still not clear. Based on the NCEP/NCAR reanalysis data over the last 35 years and by using the NOAA HYSPLIT trajectory model, we show that Erebus volcano gas emissions (including HCl and SO2) can reach the Antarctic stratosphere via high-latitude cyclones with the annual average probability Pbarann. of at least ∼0.235 (23.5%). Depending on Erebus activity, this corresponds to additional annual stratospheric HCl mass of 1.0-14.3 kilotons (kt) and SO2 mass of 1.4-19.7 kt. Thus, Erebus volcano is the natural and powerful source of additional stratospheric HCl and SO2, and hence, the cause of the Antarctic ozone depletion, together with man-made chlorofluorocarbons.

  12. 77 FR 16566 - Notice of Permit Applications Received under the Antarctic Conservation Act of 1978

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-21

    ... Notice of Permit Applications Received under the Antarctic Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of... applications received to conduct activities regulated under the Antarctic Conservation Act of 1978, Public...

  13. 78 FR 41959 - Notice of Permit Modification Received Under the Antarctic Conservation Act of 1978

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-12

    ... activities occurring in Antarctic Specially Protected Areas (ASPA) or involving Antarctic Flora and Fauna. Starting in 2013, all new permits issued for ASPA entry or involving Antarctic Flora and Flora require the... Flora and Fauna issued prior to 2013 that require the permittee to submit an annual report to...

  14. Dynamic constraints on CO2 uptake by an iron-fertilized Antarctic

    NASA Technical Reports Server (NTRS)

    Peng, Tsung-Hung; Broecker, Wallace S.; Oestlund, H. G.

    1992-01-01

    The topics covered include the following: tracer distribution and dynamics in the Antarctic Ocean; a model of Antarctic and Non-Antarctic Oceans; effects on an anthropogenically affected atmosphere; effects of seasonal iron fertilization; and implications of the South Atlantic Ventilation Experiment C-14 results.

  15. 77 FR 46528 - Notice of Permits Issued Under the Antarctic Conservation Act of 1978

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-03

    ... Notice of Permits Issued Under the Antarctic Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of permits issued under the Antarctic Conservation of 1978, Public Law 95-541. SUMMARY... Antarctic Conservation Act of 1978. This is the required notice. FOR FURTHER INFORMATION CONTACT: Nadene...

  16. 77 FR 56876 - Notice of Permits Issued Under the Antarctic Conservation Act of 1978

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-14

    ... Notice of Permits Issued Under the Antarctic Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of permits issued under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY... Antarctic Conservation Act of 1978. This is the required notice. FOR FURTHER INFORMATION CONTACT: Nadene...

  17. Reproductive performance and organochlorine pollutants in an Antarctic marine top predator: the south polar skua.

    PubMed

    Bustnes, Jan O; Tveraa, Torkild; Varpe, Øystein; Henden, John A; Skaare, Janneche U

    2007-10-01

    Despite low levels of organochlorine contaminants (OCs) in Antarctic biota, some compounds may exceed the levels in equivalent Arctic species, and previous studies have found biochemical evidence of pollutant exposure in south polar skuas (Catharacta maccormicki), a common marine top predator in the region. In this study we examined relationships between fitness components (fecundity and adult return rate between breeding seasons) and concentrations of OCs in this species. In 65 nests, both males and females were caught, and using principal component analyses (PCA) we produced composite measurements (PC1 and PC2) of six highly correlated OCs measured in blood samples. Although the concentrations of OC were below those documented to have reproductive effects in other aquatic birds, we found that the eggs of females with high levels of OCs in the blood hatched later, and their chicks were in poorer condition at hatching, than females with low OC levels. Thus OCs may delay reproduction and reduce foetal growth in the skuas. However, there was no relationship between the parents' OC residues and the occurrence of non-viable eggs, although the proportion of nests containing non-viable eggs was high (47%). Moreover, there were no significant relationships between OCs and reproductive variables in males, even if males had higher OC levels than females, and no associations between OCs and adult return rate between breeding seasons. PMID:17561256

  18. Evidence for temperate conditions along the Antarctic peninsula during the Early Tertiary

    SciTech Connect

    Zinsmeister, W.J.

    1985-01-01

    Several investigators based on deep sea glacial marine sediments from the southern oceans and volcanic sequences in West Antarctica have suggested extreme glacial conditions existed around Antarctica during the early Tertiary. Their data suggest ice sheets with ice shelves greater than those today were present on Antarctica by the late Eocene. If these data are correct, conditions during the Eocene along the Peninsula were similar to those that exist today. Late Eocene faunas and floras from Seymour Island indicate that conditions along the Peninsula were temperature. No paleontologic or geologic evidence have been obtained from Seymour Island (64/degree/18'S) to support the existence of glacial conditions along the northern part of the Peninsula during the early Tertiary. The presence of large quantities of fossil wood and plant debris in the upper Eocene sediments on Seymour Island indicates the presence of dense forests on the Peninsula during the Eocene. The discovery of marsupial and land birds remains on Seymour Island also indicate the presence of abundant terrestrial life on the Peninsula. The occurrence of an abundant marine life on Seymour Island supports the existence of temperate conditions along the Peninsula. Similarities of the Eocene faunas and floras with present day biotas from Tasmania, New Zealand and southern South America indicate that conditions along the Antarctic Peninsula during the late Eocene were comparable to present day mid latitudes of the southern hemisphere.

  19. Contribution of enhanced Antarctic Bottom Water formation to Antarctic warm events and millennial-scale atmospheric CO2 increase

    NASA Astrophysics Data System (ADS)

    Menviel, L.; Spence, P.; England, M. H.

    2014-12-01

    During Marine Isotope Stage 3, the Atlantic Meridional Overturning Circulation (AMOC) weakened significantly on a millennial time-scale leading to Dansgaard-Oeschger (DO) and Heinrich stadials. Ice core records reveal that each Northern Hemisphere stadial is associated with a warming over Antarctica, so-called Antarctic Isotope Maximum (AIM), and that atmospheric CO2 varies in phase with Antarctic temperature. Here we perform transient simulations spanning the period 50-34 ka B.P. with two Earth System Models (LOVECLIM and the UVic ESCM) to understand the link between changes in the AMOC, changes in high latitude Southern Hemispheric climate and evolution of atmospheric CO2. Given the latest Antarctic ice core chronology, we find that part of the atmospheric CO2 increase occurring during AIM12 (DO12, ~48 ka B.P.) and at the end of AIM8 (DO8, 38 ka B.P.) can be attributed to the AMOC resumption. In contrast, the atmospheric CO2 increase observed at the beginning of AIM8 (~39.6 ka B.P.) occurs during a period of weak AMOC and can instead be explained by enhanced Antarctic Bottom Water production. Enhanced Antarctic Bottom Water formation is shown to effectively ventilate the deep Pacific carbon and thus lead to CO2 outgassing into the atmosphere. In addition, changes in the AMOC alone are not sufficient to explain the largest Antarctic Isotope Maxima (namely AIM12 and AIM8). Stronger formation of Antarctic Bottom Water during AIM12 and AIM8 enhances the southern high latitude warming and leads to a better agreement with high southern latitude paleoproxy records. The robustness of this southern warming response is tested using an eddy-permitting coupled ocean sea-ice model. We show that stronger Antarctic Bottom Water formation contributes to Southern Ocean surface warming by increasing the Southern Ocean meridional heat transport. Finally, our simulations also suggest that the Antarctic cooling should be in phase, or lag by a maximum of ~200 years, the North Atlantic

  20. Antarctic DNA moving forward: genomic plasticity and biotechnological potential.

    PubMed

    Martínez-Rosales, Cecilia; Fullana, Natalia; Musto, Héctor; Castro-Sowinski, Susana

    2012-06-01

    Antarctica is the coldest, driest, and windiest continent, where only cold-adapted organisms survive. It has been frequently cited as a pristine place, but it has a highly diverse microbial community that is continually seeded by nonindigenous microorganisms. In addition to the intromission of 'alien' microorganisms, global warming strongly affects microbial Antarctic communities, changing the genes (qualitatively and quantitatively) potentially available for horizontal gene transfer. Several mobile genetic elements have been described in Antarctic bacteria (including plasmids, transposons, integrons, and genomic islands), and the data support that they are actively involved in bacterial evolution in the Antarctic environment. In addition, this environment is a genomic source for the identification of novel molecules, and many investigators have used culture-dependent and culture-independent approaches to identify cold-adapted proteins. Some of them are described in this review. We also describe studies for the design of new recombinant technologies for the production of 'difficult' proteins. PMID:22360528

  1. A data bank of Antarctic surface temperature and pressure data

    SciTech Connect

    Jones, P.D.; Limbert, D.W.S.

    1987-06-01

    A data bank of monthly-mean surface air temperature and sea-level or station-level pressures is presented for 29 stations over the Antarctic region south of 60/sup 0/S. Considerable attempts have been made to locate missing data in nationally published sources and in World Weather Records. By cross-checking neighboring station data, suspect values have been either verified or corrected. At four sites in the Antarctic Peninsula region, composite records were produced by amalgamating records from a number of short and longer length records at or near the key sites. The four sites were Bellingshausen, Faraday, Esperenza and Rothera. The mean Antarctic temperature series produced by Raper et al. (1984) is updated using the same method of calculation.

  2. Activity and bacterial diversity of snow around Russian Antarctic stations.

    PubMed

    Lopatina, Anna; Krylenkov, Vjacheslav; Severinov, Konstantin

    2013-11-01

    The diversity and temporal dynamics of bacterial communities in pristine snow around two Russian Antarctic stations was investigated. Taxonomic analysis of rDNA libraries revealed that snow communities were dominated by bacteria from a small number of operational taxonomic units (OTUs) that underwent dramatic swings in abundance between the 54th (2008-2009) and 55th (2009-2010) Russian Antarctic expeditions. Moreover, analysis of the 55th expedition samples indicated that there was very little, if any, correspondence in abundance of clones belonging to the same OTU present in rDNA and rRNA libraries. The latter result suggests that most rDNA clones originate from bacteria that are not alive and/or active and may have been deposited on the snow surface from the atmosphere. In contrast, clones most abundant in rRNA libraries (mostly belonging to Variovorax, Janthinobacterium, Pseudomonas, and Sphingomonas genera) may be considered as endogenous Antarctic snow inhabitants. PMID:24012540

  3. Detection of a novel genotype of Cryptosporidium in Antarctic pinnipeds.

    PubMed

    Rengifo-Herrera, Claudia; Ortega-Mora, Luis Miguel; Gómez-Bautista, Mercedes; García-Peña, Francisco Javier; García-Párraga, Daniel; Pedraza-Díaz, Susana

    2013-01-16

    A study was conducted to investigate the presence of Cryptosporidium and Giardia in Antarctic marine mammals. A total of 270 faecal samples from different species of pinnipeds from different locations in the South Shetland Islands and Antarctic Peninsula were analysed by immunofluorescence microscopy and PCR. Cryptosporidium was detected by PCR in three samples from Southern elephant seals (Mirounga leonina) and 2 Weddell seals (Leptonychotes weddellii). However, no oocysts were observed in any of the samples by immunofluorescence microscopy. Molecular characterisation of the isolates, using the 18S rDNA, the HSP70 and the COWP loci, revealed the presence of a Cryptosporidium sp., previously reported from an Antarctic Southern elephant seal, in the elephant seals and a novel genotype in Weddell seals. Giardia could not be detected in any of the samples analysed. PMID:23021408

  4. High diversity of the viral community from an Antarctic lake.

    PubMed

    López-Bueno, Alberto; Tamames, Javier; Velázquez, David; Moya, Andrés; Quesada, Antonio; Alcamí, Antonio

    2009-11-01

    Viruses are the most abundant biological entities and can control microbial communities, but their identity in terrestrial and freshwater Antarctic ecosystems is unknown. The genetic structure of an Antarctic lake viral community revealed unexpected genetic richness distributed across the highest number of viral families that have been found to date in aquatic viral metagenomes. In contrast to other known aquatic viromes, which are dominated by bacteriophage sequences, this Antarctic virus assemblage had a large proportion of sequences related to eukaryotic viruses, including phycodnaviruses and single-stranded DNA (ssDNA) viruses not previously identified in aquatic environments. We also observed that the transition from an ice-covered lake in spring to an open-water lake in summer led to a change from a ssDNA- to a double-stranded DNA-virus-dominated assemblage, possibly reflecting a seasonal shift in host organisms. PMID:19892985

  5. Evidence for an extensive Antarctic Ice Sheet by 37 Ma

    NASA Astrophysics Data System (ADS)

    Carter, Andrew; Riley, Teal; Hillenbrand, Claus-Dieter; Rittner, Martin

    2016-04-01

    We present observational evidence that both the East and West Antarctic ice sheets had expanded to the coast by 37 Ma, predating, by at least 3 Myr, a major drop in atmospheric CO2 at the Eocene-Oligocene boundary widely considered responsible for Antarctic Ice Sheet expansion. Our evidence comes from the provenance (geochronology, thermochronometry, mineralogy) of iceberg-rafted debris identified in Late Eocene marine sediments from (ODP) Leg 113 Site 696 in the NW Weddell Sea. The existence of an significant Antarctic Ice Sheet in a Late Eocene high pCO2 world calls into question the role of atmospheric CO2 concentrations as the dominant mechanism for ice sheet expansion and whether topography and ocean circulation only play a secondary role.

  6. (Environmental impact statement on the US Antarctic program)

    SciTech Connect

    Reed, R.M.; Railsback, S.F.; McLean, R.B.

    1989-12-22

    Three staff members from Oak Ridge National Laboratory (ORNL) participated in a site visit to US Antarctic Program (USAP) facilities at McMurdo Station, Amundsen-Scott South Pole Station, and remote field and support sites. Interviews were conducted with National Science Foundation, Navy, and ITT/Antarctic Services staff responsible for environmental management functions. The ORNL team visited all facilities at McMurdo Station, three remote field camps, a Navy refueling facility, South Pole Station, and Scott Base (a New Zealand installation). In general, the team found that environmental impacts of the USAP are minor for the Antarctic continent as a whole. Improvements for the handling and disposal of solid wastes and the discharge of wastewaters that have been initiated should help minimize environmental impacts of USAP activities. The information collected during the site visit will be used in a draft supplemental environmental impact statement on the USAP to be published for public review in June 1990.

  7. Antarctic field tests of SARSAT personal locater beacons

    NASA Technical Reports Server (NTRS)

    Bindschadler, Robert

    1987-01-01

    Field tests of SARSAT personal locater beacons were conducted in the Antarctic to assess the viability of using these beacons to increase the safety of Antarctic field parties. Data were collected on the extent to which dry or wet snow, melting conditions, crevasse walls and snow bridges affected the ability of the SARSAT satellite to calculate an accurate position of the beacon. Average response time between beacon turn on and alert reception in McMurdo was between 4 and 5 hours for these tests. It is concluded that the SARSAT system is viable for Antarctic operations and it is recommended that it be implemented for future field operations. Because of obstruction of line-of-sight between beacon and satellite degrades the accuracy of the location calculation (particularly in wet snow), it is further recommended that field parties have sufficient numbers of beacons to insure that in an emergency, one will be able to operate from the surface.

  8. Competition between West Indian anoles and birds

    SciTech Connect

    Waide, R.B.; Reagan, D.P.

    1983-01-01

    Wright (1981) noted an inverse correlation between anole and insectivorous bird biomass in sclerophyll scrub habitats on seven West Indian islands. Anole biomass decreased and insectivorous bird biomass increased with increasing island size. He proposed the following explanation for this pattern: Anoles and insectivorous birds compete directly for arthropod prey, and anoles experience ecological release upon the extinction of an avian competitor. Bird populations are in greater danger of extinction on small rather than large islands in the West Indies, while anole populations seldom become extinct. Hence, anoles should experience ecological release and the resulting increase in abundance more often on small islands, while avian competitors of anoles should be relatively more abundant on large islands. Wright further states that in the process of expanding population size and taking a greater proportion of available anthropod prey after the extinction of an avian competitor, anoles may inhibit recolonization by insectivorous birds on small islands in the West Indes. Here we taken exception to Wright's argument for the following reasons: (1) An alternative hypothesis, that differences in predation account for the observed pattern, is at least as likely as the extinction-mediated competition hypothesis. Wright's superficial treatment of predation ignores the substantial and well-documented impact of introduced mammals and other predators on both lizards and birds. (2) Evidence of significant dietary overlap between birds and anoles is weak, at best. (3) Patterns observed in sclerophyll scrub cannot be generalized to other island habitats.

  9. Pheromones in birds: myth or reality?

    PubMed Central

    Caro, Samuel P.; Balthazart, Jacques

    2012-01-01

    Birds are anosmic or at best microsmatic… This misbelief persisted until very recently and has strongly influenced the outcome of communication studies in birds, with olfaction remaining neglected as compared to acoustic and visual channels. However, there is now clear empirical evidence showing that olfaction is perfectly functional in birds and birds use olfactory information in a variety of ethological contexts. Although the existence of pheromones has never been formally demonstrated in this vertebrate class, different groups of birds, such as petrels, auklets and ducks have been shown to produce specific scents that could play a significant role in within-species social interactions. Behavioral experiments have indeed demonstrated that these odors influence the behavior of conspecifics. Additionally, in quail, deprivation of olfactory inputs decreases neuronal activation induced by sexual interactions with a female. It seems therefore well established that birds enjoy a functional sense of smell and a fast growing body of experimental evidence suggests that they use this channel of olfactory communication to control their social life. The unequivocal identification of an avian pheromone is, however, still ahead of us but there are now many exciting opportunities to unravel the behavioral and physiological particularities of chemical communication in birds. PMID:20490809

  10. Overseas seed dispersal by migratory birds.

    PubMed

    Viana, Duarte S; Gangoso, Laura; Bouten, Willem; Figuerola, Jordi

    2016-01-13

    Long-distance dispersal (LDD) promotes the colonization of isolated and remote habitats, and thus it has been proposed as a mechanism for explaining the distributions of many species. Birds are key LDD vectors for many sessile organisms such as plants, yet LDD beyond local and regional scales has never been directly observed nor quantified. By sampling birds caught while in migratory flight by GPS-tracked wild falcons, we show that migratory birds transport seeds over hundreds of kilometres and mediate dispersal from mainland to oceanic islands. Up to 1.2% of birds that reached a small island of the Canary Archipelago (Alegranza) during their migration from Europe to Sub-Saharan Africa carried seeds in their guts. The billions of birds making seasonal migrations each year may then transport millions of seeds. None of the plant species transported by the birds occurs in Alegranza and most do not occur on nearby Canary Islands, providing a direct example of the importance of environmental filters in hampering successful colonization by immigrant species. The constant propagule pressure generated by these LDD events might, nevertheless, explain the colonization of some islands. Hence, migratory birds can mediate rapid range expansion or shifts of many plant taxa and determine their distribution. PMID:26740610

  11. Impact of estuarine pollution on birds

    USGS Publications Warehouse

    Blus, L.J.; Wiemeyer, Stanley N.; Kerwin, J.A.; Stendell, R.C.; Ohlendorf, H.M.; Stickel, L.F.

    1977-01-01

    Pollution of estuaries affects bird populations indirectly through changes in habitat and food supply. The multi-factor pollution of Chesapeake Bay has resulted in diminution of submerged aquatic plants and consequent change in food habits of the canvasback duck. Although dredge-spoil operations can improve wildlife habitat, they often result in its demise. Pollution of estuaries also affects birds directly, through chemical toxication, which may result in outright mortality or in reproductive impairment. Lead from industrial sources and roadways enters the estuaries and is accumulated in tissues of birds. Lead pellets deposited in estuaries as a result of hunting are consumed by ducks with sufficient frequency .to result m large annual die-offs from lead poisoning. Fish in certain areas, usually near industrial sources, may contain levels of mercury high enough to be hazardous to birds that consume them. Other heavy metals are present in estuarine birds, but their significance is poorly known. Oil exerts lethal or sublethal effects on birds by oiling their feathers, oiling eggs and young by contaminated parents, and by ingestion of oil-contaminated food. Organochlorine chemicals, of both agricultural and industrial origin, travel through the food chains and reach harmful levels in susceptible species of birds in certain estuarine ecosystems. Both outright mortality and reproductive impairment have occurred.

  12. Seasonal Evolution of Snow Cover on Antarctic Sea Ice

    NASA Astrophysics Data System (ADS)

    Maksym, T.; Leonard, K. C.; Trujillo, E.; White, S.; Wilkinson, J.; Stammerjohn, S. E.; Mei, J.

    2015-12-01

    Snow cover on Antarctic sea ice plays a key role in the evolution of ice thickness, its estimation from space-borne altimeters, and structuring of sea ice ecosystems. Yet until recently, there have been very few continuous observations of the seasonal evolution of snow cover on Antarctic sea ice. We present observations of the seasonal evolution of the snow cover from ice mass balance buoys (IMBs) deployed between 2009 and 2013 in the Weddell, Bellingshausen, and Amundsen Seas and the East Antarctic sector. In addition, automatic weather stations that provided direct observations of precipitation, accumulation, and blowing snow were deployed alongside IMBs in October, 2012 in the East Antarctic during the Sea Ice Physics and Ecosystem eXperiment II (SIPEX II), and in July and August, 2013 in the Weddell Sea during the Antarctic Winter Ecosystem and Climate Study (AWECS). These buoys show markedly different snow accumulation regimes in each sector, although accumulation is also strongly controlled by the local morphology of the ice cover through snow erosion and deposition during blowing snow and precipitations events. Comparisons of snow accumulation from these buoys with estimates from atmospheric reanalysis and the direct measurements of precipitation and blowing snow show that precipitation is generally not a good estimator of snow accumulation. Improved treatment of blowing snow is needed if sea ice models are to accurately simulate Antarctic snow and sea ice mass balance. In summer, melting of the snow pack is relatively modest in most cases. Nevertheless, it appears to play an important role in governing sea ice hydrology and sea ice surface properties, and hence may play an important role in modulating sea ice primary productivity.

  13. Environmental microarray analyses of Antarctic soil microbial communities.

    PubMed

    Yergeau, Etienne; Schoondermark-Stolk, Sung A; Brodie, Eoin L; Déjean, Sébastien; DeSantis, Todd Z; Gonçalves, Olivier; Piceno, Yvette M; Andersen, Gary L; Kowalchuk, George A

    2009-03-01

    Antarctic ecosystems are fascinating in their limited trophic complexity, with decomposition and nutrient cycling functions being dominated by microbial activities. Not only are Antarctic habitats exposed to extreme environmental conditions, the Antarctic Peninsula is also experiencing unequalled effects of global warming. Owing to their uniqueness and the potential impact of global warming on these pristine systems, there is considerable interest in determining the structure and function of microbial communities in the Antarctic. We therefore utilized a recently designed 16S rRNA gene microarray, the PhyloChip, which targets 8741 bacterial and archaeal taxa, to interrogate microbial communities inhabiting densely vegetated and bare fell-field soils along a latitudinal gradient ranging from 51 degrees S (Falkland Islands) to 72 degrees S (Coal Nunatak). Results indicated a clear decrease in diversity with increasing latitude, with the two southernmost sites harboring the most distinct Bacterial and Archaeal communities. The microarray approach proved more sensitive in detecting the breadth of microbial diversity than polymerase chain reaction-based bacterial 16S rRNA gene libraries of modest size ( approximately 190 clones per library). Furthermore, the relative signal intensities summed for phyla and families on the PhyloChip were significantly correlated with the relative occurrence of these taxa in clone libraries. PhyloChip data were also compared with functional gene microarray data obtained earlier, highlighting numerous significant relationships and providing evidence for a strong link between community composition and functional gene distribution in Antarctic soils. Integration of these PhyloChip data with other complementary methods provides an unprecedented understanding of the microbial diversity and community structure of terrestrial Antarctic habitats. PMID:19020556

  14. Antarctic Porifera database from the Spanish benthic expeditions

    PubMed Central

    Rios, Pilar; Cristobo, Javier

    2014-01-01

    Abstract The information about the sponges in this dataset is derived from the samples collected during five Spanish Antarctic expeditions: Bentart 94, Bentart 95, Gebrap 96, Ciemar 99/00 and Bentart 2003. Samples were collected in the Antarctic Peninsula and Bellingshausen Sea at depths ranging from 4 to 2044 m using various sampling gears. The Antarctic Porifera database from the Spanish benthic expeditions is unique as it provides information for an under-explored region of the Southern Ocean (Bellingshausen Sea). It fills an information gap on Antarctic deep-sea sponges, for which there were previously very few data. This phylum is an important part of the Antarctic biota and plays a key role in the structure of the Antarctic marine benthic community due to its considerable diversity and predominance in different areas. It is often a dominant component of Southern Ocean benthic communities. The quality of the data was controlled very thoroughly with GPS systems onboard the R/V Hesperides and by checking the data against the World Porifera Database (which is part of the World Register of Marine Species, WoRMS). The data are therefore fit for completing checklists, inclusion in biodiversity pattern analysis and niche modelling. The authors can be contacted if any additional information is needed before carrying out detailed biodiversity or biogeographic studies. The dataset currently contains 767 occurrence data items that have been checked for systematic reliability. This database is not yet complete and the collection is growing. Specimens are stored in the author’s collection at the Spanish Institute of Oceanography (IEO) in the city of Gijón (Spain). The data are available in GBIF. PMID:24843257

  15. Antarctic Data at the National Snow and Ice Data Center

    NASA Astrophysics Data System (ADS)

    Leitzell, K.; Bohlander, J. A.; Bauer, R. J.; Scambos, T. A.

    2010-12-01

    The National Snow and Ice Data Center (NSIDC) archives and distributes data related to the Earth’s cryosphere. The center has a unique and extensive archive of data related to Antarctica, supported by the National Science Foundation (NSF) Office of Polar Programs, and various NASA projects. This poster will highlight some of our newest and most significant data holdings for Antarctic ice and climate research. Antarctic data at NSIDC include: -New P.I.-contributed data sets from the Antarctic Glaciological Data Center (AGDC), an NSF-funded data archive facility at NSIDC. AGDC has been active for 12 years, and houses data sets from over 150 researchers, spanning all types of research in the Antarctic. -MODIS Mosaic of Antarctica (MOA) 2009 was released in fall of 2010. This is a 125 meter, resolution-enhanced seamless mosaic of Antarctica, compiled from over 250 MODIS images acquired between 20 November 2008 and 01 March 2009. It provides a uniquely clear and detailed view of the continent's subtle ice flow and surface features. The new version offers the opportunity for change detection (ice flow, iceberg calving events, changes in ice flow and wind features) in the five years between early 2009 and an identically processed mosaic assembled in 2004. -NASA’s “Making Earth Science Data Records for Use in Research Environments” (MEaSUREs) provides ice velocity data for all of Antarctica, derived from Interferometric Synthetic Aperture radar (InSAR) analysis. We will show the access and browse software to be used for MEaSURES/Antarctic Ice Velocity, called the Antarctic Cryosphere Access Portal (A-CAP).

  16. Antarctic Porifera database from the Spanish benthic expeditions.

    PubMed

    Rios, Pilar; Cristobo, Javier

    2014-01-01

    THE INFORMATION ABOUT THE SPONGES IN THIS DATASET IS DERIVED FROM THE SAMPLES COLLECTED DURING FIVE SPANISH ANTARCTIC EXPEDITIONS: Bentart 94, Bentart 95, Gebrap 96, Ciemar 99/00 and Bentart 2003. Samples were collected in the Antarctic Peninsula and Bellingshausen Sea at depths ranging from 4 to 2044 m using various sampling gears. The Antarctic Porifera database from the Spanish benthic expeditions is unique as it provides information for an under-explored region of the Southern Ocean (Bellingshausen Sea). It fills an information gap on Antarctic deep-sea sponges, for which there were previously very few data. This phylum is an important part of the Antarctic biota and plays a key role in the structure of the Antarctic marine benthic community due to its considerable diversity and predominance in different areas. It is often a dominant component of Southern Ocean benthic communities. The quality of the data was controlled very thoroughly with GPS systems onboard the R/V Hesperides and by checking the data against the World Porifera Database (which is part of the World Register of Marine Species, WoRMS). The data are therefore fit for completing checklists, inclusion in biodiversity pattern analysis and niche modelling. The authors can be contacted if any additional information is needed before carrying out detailed biodiversity or biogeographic studies. The dataset currently contains 767 occurrence data items that have been checked for systematic reliability. This database is not yet complete and the collection is growing. Specimens are stored in the author's collection at the Spanish Institute of Oceanography (IEO) in the city of Gijón (Spain). The data are available in GBIF. PMID:24843257

  17. Sea ice production variability in Antarctic coastal polynyas

    NASA Astrophysics Data System (ADS)

    Tamura, Takeshi; Ohshima, Kay I.; Fraser, Alexander D.; Williams, Guy D.

    2016-05-01

    Enhanced sea ice production (SIP) in Antarctic coastal polynyas forms dense shelf water (DSW), leading to Antarctic Bottom Water (AABW) formation that ultimately drives the lower limb of the meridional overturning circulation. Some studies suggest that the variability of SIP in Antarctic coastal polynyas is driven by the influence of atmospheric forcing, i.e., surface winds and air temperature. Our previous mapping of SIP in 13 major Antarctic coastal polynyas from 1992 to 2007, using a heat flux calculation with ice thickness data derived from satellite data, is extended here to examine the interannual and seasonal variability of SIP from 1992 to 2013. The interannual variability of total ice production correlates more strongly with polynya extent than with atmospheric forcing, with the exception of the Shackleton Polynya, which correlates well with wind. There is no coherent signal in the interannual variability between the major Antarctic coastal polynyas. We find that stochastic changes to the coastal "icescape," i.e., ice shelves, floating glaciers, fast ice, together with offshore first-year ice, are also important factors driving SIP variability on multiyear time scales. Both the Ross Ice Shelf Polynya and Mertz Glacier Polynya experienced a significant reduction in SIP due to calving events and the repositioning of icebergs and fast ice. Our results also show opposing trends between polynya-based SIP and sea ice extent in key regions of Antarctic sea ice change. Close monitoring of coastal icescape dynamics and change is essential to better understand the long-term impact of coastal polynya variability and its influence on regional AABW production.

  18. Cenozoic evolution of the Antarctic Peninsula continental margin

    SciTech Connect

    Anderson, J.B. )

    1990-05-01

    Cenozoic evolution of the Antarctic Peninsula continental margin has involved a series of ridge (Aluk Ridge)-trench collisions between the Pacific and Antarctic plates. Subduction occurred episodically between segments of the Pacific plate that are bounded by major fracture zones. The age of ridge-trench collisions decreases from south to north along the margin. The very northern part of the margin, between the Hero and Shackleton fracture zones, has the last surviving Aluk-Antarctic spreading ridge segments and the only remaining trench topography. The sedimentary cover on the northern margin is relatively thin generally less than 1.5 km, thus providing a unique setting in which to examine margin evolution using high resolution seismic methods. Over 5,000 km of high resolution (water gun) seismic profiles were acquired from the Antarctic Peninsula margin during four cruises to the region. The margin is divided into discrete fracture-zone-bounded segments; each segment displays different styles of development. Highly tectonized active margin sequences have been buried beneath a seaward-thickening sediment wedge that represents the passive stage of margin development Ice caps, which have existed in the Antarctic Peninsula region since at least the late Oligocene, have advanced onto the continental shelf on numerous occasions, eroding hundreds of meters into the shelf and depositing a thick sequence of deposits characterized by till tongues and glacial troughs. Glacial erosion has been the main factor responsible for overdeepening of the shelf; isostasy is of secondary importance. As the shelf was lowered by glacial erosion, it was able to accommodate thicker and more unstable marine ice sheets. The shelf also became a vast reservoir for cold, saline shelf water, one of the key ingredients of Antarctic bottom water.

  19. Unexpectedly high ultrafine aerosol concentrations above East Antarctic sea ice

    NASA Astrophysics Data System (ADS)

    Humphries, R. S.; Klekociuk, A. R.; Schofield, R.; Keywood, M.; Ward, J.; Wilson, S. R.

    2016-02-01

    Better characterisation of aerosol processes in pristine, natural environments, such as Antarctica, have recently been shown to lead to the largest reduction in uncertainties in our understanding of radiative forcing. Our understanding of aerosols in the Antarctic region is currently based on measurements that are often limited to boundary layer air masses at spatially sparse coastal and continental research stations, with only a handful of studies in the vast sea-ice region. In this paper, the first observational study of sub-micron aerosols in the East Antarctic sea ice region is presented. Measurements were conducted aboard the icebreaker Aurora Australis in spring 2012 and found that boundary layer condensation nuclei (CN3) concentrations exhibited a five-fold increase moving across the polar front, with mean polar cell concentrations of 1130 cm-3 - higher than any observed elsewhere in the Antarctic and Southern Ocean region. The absence of evidence for aerosol growth suggested that nucleation was unlikely to be local. Air parcel trajectories indicated significant influence from the free troposphere above the Antarctic continent, implicating this as the likely nucleation region for surface aerosol, a similar conclusion to previous Antarctic aerosol studies. The highest aerosol concentrations were found to correlate with low-pressure systems, suggesting that the passage of cyclones provided an accelerated pathway, delivering air masses quickly from the free troposphere to the surface. After descent from the Antarctic free troposphere, trajectories suggest that sea-ice boundary layer air masses travelled equatorward into the low-albedo Southern Ocean region, transporting with them emissions and these aerosol nuclei which, after growth, may potentially impact on the region's radiative balance. The high aerosol concentrations and their transport pathways described here, could help reduce the discrepancy currently present between simulations and observations of

  20. Global impact of the Antarctic ozone hole: Chemical Propagation

    SciTech Connect

    Prather, M.; Jaffe, A.H. )

    1990-03-20

    A model is presented for the chemical mixing of stratosphere air over spatial scales from tens of kilometers to meters. Photochemistry, molecular diffusion, and strain (the stretching of air parcels due to wind shear) are combined into a single one-dimensional model. The model is applied to the case in which chemically perturbed air parcels from the Antarctic stratosphere are transported to mid-latitudes and strained into thin ribbon-like filaments until they are diffusively mixed with the ambient stratosphere. For this sensitivity study the authors consider four types of Antarctic air: a control case representing unprocessed polar air; heterogeneous processing by polar stratospheric clouds (PSCs) that has repartitioned the Cl{sub x} and NO{sub y} families; processing that also includes denitrification and dehydration; and all processing plus 90% ozone depletion. Large abundances of ClO, resulting initially from heterogeneous processing of stratospheric air on PSCs, are sustained by extensive denitrification. (One exception is the case of Antarctic air with major ozone depletion in which ClO is converted rapidly to HCl upon release of small amounts of NO{sub x} as a result of the extremely nonlinear Cl{sub x}-NO{sub y} chemical system.) ClO concentrations in the mid-latitude stratosphere should be enhanced by as much as a factor of 5 due to the mixing of air processed around the Antarctic vortex and will remain elevated for most of the following season. Chemical propagation of the Antarctic ozone hole occurs in two phases: rapid loss of ozone in the heterogeneously processed parcels as they evolve in isolation, and more slowly, a relative recovery of ozone over the following months. Another important effect is the transport of denitrified Antarctic air reducing NO{sub x} and hence the total catalytic destruction of ozone throughout the southern mid-latitudes.

  1. Antarctic Marine Biodiversity and Deep-Sea Hydrothermal Vents

    PubMed Central

    Chown, Steven L.

    2012-01-01

    The diversity of many marine benthic groups is unlike that of most other taxa. Rather than declining from the tropics to the poles, much of the benthos shows high diversity in the Southern Ocean. Moreover, many species are unique to the Antarctic region. Recent work has shown that this is also true of the communities of Antarctic deep-sea hydrothermal vents. Vent ecosystems have been documented from many sites across the globe, associated with the thermally and chemically variable habitats found around these, typically high temperature, streams that are rich in reduced compounds and polymetallic sulphides. The animal communities of the East Scotia Ridge vent ecosystems are very different to those elsewhere, though the microbiota, which form the basis of vent food webs, show less differentiation. Much of the biological significance of deep-sea hydrothermal vents lies in their biodiversity, the diverse biochemistry of their bacteria, the remarkable symbioses among many of the marine animals and these bacteria, and the prospects that investigations of these systems hold for understanding the conditions that may have led to the first appearance of life. The discovery of diverse and unusual Antarctic hydrothermal vent ecosystems provides opportunities for new understanding in these fields. Moreover, the Antarctic vents south of 60°S benefit from automatic conservation under the Convention on the Conservation of Antarctic Marine Living Resources and the Antarctic Treaty. Other deep-sea hydrothermal vents located in international waters are not protected and may be threatened by growing interests in deep-sea mining. PMID:22235192

  2. Arctic and Antarctic Topography Measurements Using LVIS

    NASA Astrophysics Data System (ADS)

    Hofton, M. A.; Blair, J. B.; Rabine, D.; Beckley, M.; Brooks, C.; Cornejo, H.

    2015-12-01

    Wide-swath, medium-footprint laser altimetry (lidar) is routinely used to monitor large areas of the Arctic, Antarctic and other environs. As part of NASA's Operation Icebridge and ARISE missions, NASA's LVIS and LVIS-GH systems operating on medium-high altitude platforms have collected over 350,000km2 of surface elevation and structure measurements, providing data sets to both support and enhance future space-based lidar missions such as ICESAT-2 and GEDI. Using the LVIS systems over ice surfaces, typical elevation precision and accuracy is at the 10 cm level, assessed using inter and intra-mission crossovers. An updated version of the LVIS system is under development combining the latest technology with updated and more capable approaches to operating procedures and data processing. The sensor will be available in late summer 2016 as part of a new NASA geodetic imaging lidar facility with goals of providing up to 5 times more data than present with 2 month turnaround at much reduced cost to the end user. A review of data processing approaches will be presented, along with results from the recent ARISE 2014 campaign in the Arctic. Mission highlights included a 1000 km-long transect from open water to sea ice along 140W, a 600 km-long transect along an orbit track of ESA's Cryosat-2 satellite with the satellite passing directly overhead at the start of the line, repeated passes over the Marginal Ice Zone throughout the ARISE campaign over the time of the sea ice minimum, data swaths along the Columbia, Portage, Spencer, Trail, and Wolverine glaciers in Alaska, and characterization of cloud top heights throughout each flight to interpret the ARISE radiation measurements.

  3. Revisiting Antarctic Circumpolar Current Transport Estimates

    NASA Astrophysics Data System (ADS)

    Sommers, L. A.; Donohue, K. A.; Rosburg, K.

    2014-12-01

    The Antarctic Circumpolar Current (ACC) is the world's strongest current, and acts as a conduit that transports water between Atlantic, Pacific, and Indian Oceans. ACC transport is a key metric used to evaluate the accuracy of ocean and climate models. The canonical transport of 134 Sv through Drake Passage, the narrowest choke point of the ACC, derives from a year-long experiment conducted in 1979 (DRAKE79). Recent studies suggest that this historical value may be biased low by as much as 20%. DRAKE79 transport estimates resulted from a complicated synthesis of historical data and in-situ measurements, and relied heavily on the outcome of referencing three hydrographic sections with directly measured currents. This study focuses on evaluating DRAKE79's geostrophic referencing technique. We hypothesized that the horizontal spacing and temporal averaging of current meters led to a bias in the historical estimate. Southern Ocean State Estimate (SOSE) was used as a test bed to evaluate DRAKE79 methods. A mean AAC transport of 181.5 ± 17.6 Sv was obtained by applying DRAKE79 methods to 2005 SOSE output. This value is greater than SOSE's "true" geostrophic transport (153.0 ± 5.7) by 29 Sv. This difference resulted primarily from linear interpolation between two lost moorings; however the horizontal spacing of the current meters did not resolve the narrow jets of the ACC regardless of mooring loss. Within SOSE, geostrophic transports referenced with velocities at all mooring locations resulted in a mean transport of 161.0 ± 10.2 Sv. Temporal smoothing of the reference velocities, using up to a 20-day running mean, had minimal impact on the mean transport estimate. A next step would evaluate whether the mooring positions should be modified within SOSE to capture the same circulation features as DRAKE79.

  4. Viral distribution and activity in Antarctic waters

    NASA Astrophysics Data System (ADS)

    Guixa-Boixereu, Núria; Vaqué, Dolors; Gasol, Josep M.; Sánchez-Cámara, Jaime; Pedrós-Alió, Carlos

    Variability in abundance of virus-like particles (VLP), VLP decay rates and prokaryotic mortality due to viral infection were determined in three Antarctic areas: Bellingshausen Sea, Bransfield Strait and Gerlache Strait, during December 1995 and February 1996. VLP abundance showed very small spatial variability in the three areas (7×10 6-2×10 7 VLP ml -1). VLP abundance, on the other hand, decreased one order of magnitude from the surface to the bottom, in two stations where deep vertical profiles were sampled. Low seasonal variability in VLP abundance was found when comparing each area separately. Diel VLP variability was also very low. VLP abundance showed the lowest values when solar irradiation was maximal, in two of the three stations where diel cycles were examined. Viral decay rates (VDR) were determined using KCN in two kinds of experiments. Type 1 experiments were performed in 6 stations to determine viral decay. Type 2 experiments were carried out in 2 stations to examine the influence of temperature and organic matter concentration on viral decay. VDR was not influenced by these parameters. Prokaryotic mortality due to viral infection was always higher than that due to bacterivores in the stations where both factors of prokaryotic mortality were measured. Viral infection accounted for all the prokaryotic heterotrophic production in Bellingshausen Sea and Gerlache Strait and for half of the prokaryotic heterotrophic production in Bransfield Strait. These high values of prokaryotic mortality due to viral infection are difficult to reconcile in nature, and more work is necessary to determine the mechanisms involved in the disappearance of viruses.

  5. Microbiology and Geochemistry of Antarctic Paleosols

    NASA Astrophysics Data System (ADS)

    Mahaney, W. C.; Malloch, D.; Hancock, R. G. V.; Campbell, I. B.; Sheppard, D.

    2000-08-01

    Samples of ancient soils from horizons in paleosols from the Quartermain Mountains (Aztec and New Mountain areas of the Antarctic Dry Valleys) were analyzed for their chemical composition and microbiology to determine the accumulation and movement of salts and other soluble constituents. The salt concentrations are of special interest because they are considered to be a function of age, derived in part from nearby oceanic and high altitude atmospheric sources. The geochemistry of ancient Miocene-age paleosols in these areas is the direct result of the deposition and weathering of till, derived principally from dolerite and sandstone source rock, in association with airborne-influxed salts. Paleosols nearer the coast have greater contents of chlorine, and farther inland near the Inland Ice Sheet, nitrogen tends to increase on a relative basis. The accumulation and vertical distribution of salts and other soluble chemical elements indicate relative amounts of movement in the profile over long periods of time, to the order of several million years. Iron, both in total concentration and in the form of various extracts, indicates it can be used as a geochronometer to assess the buildup of goethite plus hematite over time in the paleosols. Trends for ferrihydrite, a partially soluble Fe-hydroxide, shows limited profile translocation that might be related to the movement of salt. Six of the eight selected subsamples from paleosol horizons in three soil profiles contained nil concentrations of bacteria and fungi. However, two horizons at depths of between three to eight centimeters yielded several colonies of the fungi Beauveria bassiana and Penicillium spp., indicating some input of organic carbon. Beauveria bassiana is often reported in association with insects and is used commercially for the biological control of some insect pests. Penicillium species are commonly isolated from Arctic, temperate and tropical soils and are known to utilize a wide variety of organic

  6. Antarctic Ozone Hole on September 17, 2001

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Satellite data show the area of this year's Antarctic ozone hole peaked at about 26 million square kilometers-roughly the size of North America-making the hole similar in size to those of the past three years, according to scientists from NASA and the National Oceanic and Atmospheric Administration (NOAA). Researchers have observed a leveling-off of the hole size and predict a slow recovery. Over the past several years the annual ozone hole over Antarctica has remained about the same in both its size and in the thickness of the ozone layer. 'This is consistent with human-produced chlorine compounds that destroy ozone reaching their peak concentrations in the atmosphere, leveling off, and now beginning a very slow decline,' said Samuel Oltmans of NOAA's Climate Monitoring and Diagnostics Laboratory, Boulder, Colo. In the near future-barring unusual events such as explosive volcanic eruptions-the severity of the ozone hole will likely remain similar to what has been seen in recent years, with year-to-year differences associated with meteorological variability. Over the longer term (30-50 years) the severity of the ozone hole in Antarctica is expected to decrease as chlorine levels in the atmosphere decline. The image above shows ozone levels on Spetember 17, 2001-the lowest levels observed this year. Dark blue colors correspond to the thinnest ozone, while light blue, green, and yellow pixels indicate progressively thicker ozone. For more information read: 2001 Ozone Hole About the Same Size as Past Three Years. Image courtesy Greg Shirah, GSFC Scientific Visualization Studio, based on data from the TOMS science team

  7. Antarctic icebergs distributions 1992-2014

    NASA Astrophysics Data System (ADS)

    Tournadre, J.; Bouhier, N.; Girard-Ardhuin, F.; Rémy, F.

    2016-01-01

    Basal melting of floating ice shelves and iceberg calving constitute the two almost equal paths of freshwater flux between the Antarctic ice cap and the Southern Ocean. The largest icebergs (>100 km2) transport most of the ice volume but their basal melting is small compared to their breaking into smaller icebergs that constitute thus the major vector of freshwater. The archives of nine altimeters have been processed to create a database of small icebergs (<8 km2) within open water containing the positions, sizes, and volumes spanning the 1992-2014 period. The intercalibrated monthly ice volumes from the different altimeters have been merged in a homogeneous 23 year climatology. The iceberg size distribution, covering the 0.1-10,000 km2 range, estimated by combining small and large icebergs size measurements follows well a power law of slope -1.52 ± 0.32 close to the -3/2 laws observed and modeled for brittle fragmentation. The global volume of ice and its distribution between the ocean basins present a very strong interannual variability only partially explained by the number of large icebergs. Indeed, vast zones of the Southern Ocean free of large icebergs are largely populated by small iceberg drifting over thousands of kilometers. The correlation between the global small and large icebergs volumes shows that small icebergs are mainly generated by large ones breaking. Drifting and trapping by sea ice can transport small icebergs for long period and distances. Small icebergs act as an ice diffuse process along large icebergs trajectories while sea ice trapping acts as a buffer delaying melting.

  8. Coastal and Marine Bird Data Base

    USGS Publications Warehouse

    Anderson, S.H.; Geissler, P.H.; Dawson, D.K.

    1980-01-01

    Summary: This report discusses the development of a coastal and marine bird data base at the Migratory Bird and Habitat Research Laboratory. The system is compared with other data bases, and suggestions for future development, such as possible adaptations for other taxonomic groups, are included. The data base is based on the Statistical Analysis System but includes extensions programmed in PL/I. The Appendix shows how the system evolved. Output examples are given for heron data and pelagic bird data which indicate the types of analyses that can be conducted and output figures. The Appendixes include a retrieval language user's guide and description of the retrieval process and listing of translator program.

  9. Space Shuttle Orbiter windshield bird impact analysis

    NASA Technical Reports Server (NTRS)

    Edelstein, Karen S.; Mccarty, Robert E.

    1988-01-01

    The NASA Space Shuttle Orbiter's windshield employs three glass panes separated by air gaps. The brittleness of the glass offers much less birdstrike energy-absorption capability than the laminated polycarbonate windshields of more conventional aircraft; attention must accordingly be given to the risk of catastrophic bird impact, and to methods of strike prevention that address bird populations around landing sites rather than the modification of the window's design. Bird populations' direct reduction, as well as careful scheduling of Orbiter landing times, are suggested as viable alternatives. The question of birdstrike-resistant glass windshield design for hypersonic aerospacecraft is discussed.

  10. Hydrochemical characteristic of different modifications of Antarctic waters

    NASA Astrophysics Data System (ADS)

    Batrak, K. V.

    2008-06-01

    The report considers the distribution of several hydrochemical components (dissolved oxygen, mineral phosphorus, dissolved silicon, and nitrate nitrogen) depending on the disposition of different structural water modifications constituting the unified Antarctic structural type. It is shown that the character of the silicon distribution in the waters of the South Polar zone is mainly determined by large-scale circulation features. The distribution of mineral phosphorus and nitrate nitrogen is characterized by a certain patchiness related to the photosynthesis intensity. An attempt was made to follow the supply and transformation of dissolved silicon, nitrates, and phosphates in the Antarctic.

  11. Oceanology of the antarctic continental shelf: Volume 43

    SciTech Connect

    Jacobs, S.S.

    1985-01-01

    This book discusses the seas of the deep continental shelf, which play an important climatic role in sea ice production, deep ocean ventilation and wastage of the Antarctic ice sheet. This volume includes analyses of measurements taken from ships and satellites, and from sea ice and glacial ice. High resolution profiling equipment, long term bottom-moored instruments, continuous remote sensors, geochemical tracers and computer models have provided the basis for new insights into the continental shelf circulation. Color plates and an accompanying GEBCO Circum-Antarctic map effectively portray the continental shelf in relation to the glaciated continent, the sea ice and the surrounding Southern Ocean.

  12. NMC stratospheric analyses during the 1987 Antarctic expedition

    NASA Technical Reports Server (NTRS)

    Gelman, Melvyn E.; Newman, Paul A.

    1988-01-01

    Stratospheric constant pressure analyses of geopotential height and temperature, produced as part of regular operations at the National Meteorological Center (NMC), were used by several participants of the Antarctic Ozone Expedition. A brief decription is given of the NMC stratospheric analyses and the data that are used to derive them. In addition, comparisons of the analysis values at the locations of radiosonde and aircraft data are presented to provide indications for assessing the representativeness of the NMC stratospheric analyses during the 1987 Antarctic winter-spring period.

  13. Balloon measurements of aerosol in the Antarctic stratosphere

    NASA Technical Reports Server (NTRS)

    Morita, Y.; Takagi, M.; Iwasaka, Y.; Ono, A.

    1985-01-01

    Three balloon soundings of aerosol were conducted from Syowa Station, Antarctica in April, June and October 1983. Number concentration and the size distribution of aerosol particles with diameter greater than 0.3 microns were measured by using a light scattering aerosol particle counter. The influence of the eruption of Mt. El Chichon on the aerosol concentration in the stratosphere was observed on October 16. Very high aerosol concentration at stratospheric heights was obtained from the first successful aerosol sounding in winter Antarctic stratosphere. The result gives direct evidence of winter enhancement in the Antarctic stratosphere.

  14. Antarctic ice streams and outflow channels on Mars

    USGS Publications Warehouse

    Lucchitta, B.K.

    2001-01-01

    New sonar images of the Antarctic sea floor reveal mega-scale glacial lineations that are strikingly similar to longitudinal flutes in martian outflow channels. The analogs suggest that ice moved through the martian channels in places and carved the flutes. The ice in martian channels may have moved like Antarctic ice streams on deformable debris saturated with water under high pore pressure. On Mars, water at the base of ice-filled channels may have come from residual water or melt water liberated during past warmer climates or higher heat flows.

  15. Hemosporidian blood parasites in seabirds—a comparative genetic study of species from Antarctic to tropical habitats

    PubMed Central

    Martínez, Javier; Hennicke, Janos; Ludynia, Katrin; Gladbach, Anja; Masello, Juan F.; Riou, Samuel; Merino, Santiago

    2010-01-01

    Whereas some bird species are heavily affected by blood parasites in the wild, others reportedly are not. Seabirds, in particular, are often free from blood parasites, even in the presence of potential vectors. By means of polymerase chain reaction, we amplified a DNA fragment from the cytochrome b gene to detect parasites of the genera Plasmodium, Leucocytozoon, and Haemoproteus in 14 seabird species, ranging from Antarctica to the tropical Indian Ocean. We did not detect parasites in 11 of these species, including one Antarctic, four subantarctic, two temperate, and four tropical species. On the other hand, two subantarctic species, thin-billed prions Pachyptila belcheri and dolphin gulls Larus scoresbii, were found infected. One of 28 thin-billed prions had a Plasmodium infection whose DNA sequence was identical to lineage P22 of Plasmodium relictum, and one of 20 dolphin gulls was infected with a Haemoproteus lineage which appears phylogenetically clustered with parasites species isolated from passeriform birds such as Haemoproteus lanii, Haemoproteus magnus, Haemoproteus fringillae, Haemoproteus sylvae, Haemoproteus payevskyi, and Haemoproteus belopolskyi. In addition, we found a high parasite prevalence in a single tropical species, the Christmas Island frigatebird Fregata andrewsi, where 56% of sampled adults were infected with Haemoproteus. The latter formed a monophyletic group that includes a Haemoproteus line from Eastern Asian black-tailed gulls Larus crassirostris. Our results are in agreement with those showing that (a) seabirds are poor in hemosporidians and (b) latitude could be a determining factor to predict the presence of hemosporidians in birds. However, further studies should explore the relative importance of extrinsic and intrinsic factors on parasite prevalence, in particular using phylogenetically controlled comparative analyses, systematic sampling and screening of vectors, and within-species comparisons. PMID:20652673

  16. Hemosporidian blood parasites in seabirds—a comparative genetic study of species from Antarctic to tropical habitats

    NASA Astrophysics Data System (ADS)

    Quillfeldt, Petra; Martínez, Javier; Hennicke, Janos; Ludynia, Katrin; Gladbach, Anja; Masello, Juan F.; Riou, Samuel; Merino, Santiago

    2010-09-01

    Whereas some bird species are heavily affected by blood parasites in the wild, others reportedly are not. Seabirds, in particular, are often free from blood parasites, even in the presence of potential vectors. By means of polymerase chain reaction, we amplified a DNA fragment from the cytochrome b gene to detect parasites of the genera Plasmodium, Leucocytozoon, and Haemoproteus in 14 seabird species, ranging from Antarctica to the tropical Indian Ocean. We did not detect parasites in 11 of these species, including one Antarctic, four subantarctic, two temperate, and four tropical species. On the other hand, two subantarctic species, thin-billed prions Pachyptila belcheri and dolphin gulls Larus scoresbii, were found infected. One of 28 thin-billed prions had a Plasmodium infection whose DNA sequence was identical to lineage P22 of Plasmodium relictum, and one of 20 dolphin gulls was infected with a Haemoproteus lineage which appears phylogenetically clustered with parasites species isolated from passeriform birds such as Haemoproteus lanii, Haemoproteus magnus, Haemoproteus fringillae, Haemoproteus sylvae, Haemoproteus payevskyi, and Haemoproteus belopolskyi. In addition, we found a high parasite prevalence in a single tropical species, the Christmas Island frigatebird Fregata andrewsi, where 56% of sampled adults were infected with Haemoproteus. The latter formed a monophyletic group that includes a Haemoproteus line from Eastern Asian black-tailed gulls Larus crassirostris. Our results are in agreement with those showing that (a) seabirds are poor in hemosporidians and (b) latitude could be a determining factor to predict the presence of hemosporidians in birds. However, further studies should explore the relative importance of extrinsic and intrinsic factors on parasite prevalence, in particular using phylogenetically controlled comparative analyses, systematic sampling and screening of vectors, and within-species comparisons.

  17. Models for the volume of earliest Oligocene Antarctic ice on reconstructed Antarctic topography

    NASA Astrophysics Data System (ADS)

    Wilson, D. S.; Pollard, D.; DeConto, R.; Jamieson, S.; Luyendyk, B. P.

    2011-12-01

    The Eocene-Oligocene (E-O) climate transition is widely recognized as including both growth of a substantial Antarctic ice sheet and cooling of the deep ocean, recorded most quantitatively by a sharp increase in benthic marine oxygen isotopes. As the oceanographic record of oxygen isotopes depends on both ice volume and temperature, substantial recent effort has been directed to interpreting proxy records of temperature and sea level in order to determine the changes in ice volume and temperature. The general consensus is that the ice-volume increase at E-O is comparable to or most plausibly larger than the volume of present Antarctic ice (25.4 M km3, BEDMAP). Early models of E-O ice growth have not produced this volume. One of the factors limiting the value of the early ice-growth models is the use of present Antarctic bedrock topography as a boundary condition. The use of present topography ignores the potentially significant long-term processes of landscape evolution including glacial erosion, thermal subsidence and tectonics which are likely to have changed the relationship between topography and ice dynamics in Antarctica. We present models contrasting the ice volume supported by the present topography (BEDMAP, restored for removing the load of modern ice) with the ice volume supported by minimum and maximum estimates of reconstructed E-O topography [Wilson, D.S., et al., Antarctic topography at the Eocene-Oligocene boundary, Palaeogeogr. Palaeoclimatol. Palaeoecol., 2011, in press, doi:10.1016/j.palaeo.2011.05.028], which restore substantial areas of West Antarctica above sea level. These models are based on running a 3-D ice-sheet model to equilibrium, in a climate obtained from a look-up matrix of GENESIS GCM snapshots with atmospheric CO2 set to 2x preindustrial level, and an average Earth orbit. Using a uniformly high-friction basal boundary condition for ice sliding, our preliminary predictions for total ice volume are 23.6 Mkm3 for BEDMAP, 35.6 Mkm3 for

  18. Characterising Antarctic and Southern Ocean Lithosphere with Magnetic and Gravity Imaging of East Antarctic Rift Systems

    NASA Astrophysics Data System (ADS)

    Vaughan, A. P.; Kusznir, N. J.; Ferraccioli, F.; Jordan, T. A.; Purucker, M. E.; Golynsky, A. V.; Rogozhina, I.

    2012-12-01

    Since the International Geophysical Year (1957), a view has prevailed that the lithospheric structure of East Antarctica is relatively homogeneous, forming a geological block of largely cratonic nature, consisting of a mosaic of Precambrian terranes, stable since the Pan-African orogeny ~500 million years ago. Recent recognition of a continental-scale rift system cutting the East Antarctic interior indicates that this is incorrect, and has crystallised an alternative view of much more recent geological activity with important implications for tectonic reconstructions and controls on ice sheet formation and stability. The newly defined East Antarctic Rift System appears to extend from at least the South Pole to the continental margin at the Lambert Rift, a distance of 2500 km. This is comparable in scale to the well-studied East African rift system. New analysis of RadarSat data pioneered by Golynsky & Golynsky indicates that further rift zones may extend the East Antarctic Rift System into widely distributed extension zones within the continent. We have carried out a pilot study, using a newly developed gravity inversion technique with existing public domain satellite data, which shows that East Antarctica consists of distinct crustal thickness provinces with anomalously thick areas separated by thin, possibly rifted crust and overall high average thickness. Understanding the nature of crustal thickness in East Antarctica is critical because: 1) Better understanding of crustal thickness in Antarctica, especially along the ocean-continent transition (OCT), will make it possible to improve the plate reconstruction fit between Antarctica, Australia and India in Gondwana and also refine constraints on how and when these continents separated; 2) crustal thickness provinces can be used to aid supercontinent reconstructions and provide new assessments of the influence of basement architecture and mechanical properties on rifting processes; 3) tracking rift zones through

  19. 50 CFR 20.42 - Transportation of birds of another.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Transportation of birds of another. 20.42... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Transportation Within the United States § 20.42 Transportation of birds of another. No person shall transport migratory game birds belonging to another...

  20. 50 CFR 20.37 - Custody of birds of another.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Custody of birds of another. 20.37 Section... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Possession § 20.37 Custody of birds of another. No person shall receive or have in custody any migratory game birds belonging to another person unless...

  1. 50 CFR 20.62 - Importation of birds of another.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Importation of birds of another. 20.62... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Importations § 20.62 Importation of birds of another. No person shall import migratory game birds belonging to another person....

  2. 50 CFR 20.20 - Migratory Bird Harvest Information Program.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Migratory Bird Harvest Information Program... IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Taking § 20.20 Migratory Bird Harvest... information will be used to provide a sampling frame for the national Migratory Bird Harvest Survey....

  3. 50 CFR 20.38 - Possession of live birds.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Possession of live birds. 20.38 Section 20... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Possession § 20.38 Possession of live birds. Every migratory game bird wounded by hunting and reduced to possession by the hunter shall be immediately...

  4. 50 CFR 20.37 - Custody of birds of another.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Custody of birds of another. 20.37 Section... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Possession § 20.37 Custody of birds of another. No person shall receive or have in custody any migratory game birds belonging to another person unless...

  5. 50 CFR 92.22 - Subsistence migratory bird species.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Subsistence migratory bird species. 92.22... (CONTINUED) MISCELLANEOUS PROVISIONS MIGRATORY BIRD SUBSISTENCE HARVEST IN ALASKA General Regulations Governing Subsistence Harvest § 92.22 Subsistence migratory bird species. You may harvest birds or...

  6. 50 CFR 20.62 - Importation of birds of another.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Importation of birds of another. 20.62... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Importations § 20.62 Importation of birds of another. No person shall import migratory game birds belonging to another person....

  7. 50 CFR 20.42 - Transportation of birds of another.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Transportation of birds of another. 20.42... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Transportation Within the United States § 20.42 Transportation of birds of another. No person shall transport migratory game birds belonging to another...

  8. 50 CFR 92.22 - Subsistence migratory bird species.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Subsistence migratory bird species. 92.22... (CONTINUED) MISCELLANEOUS PROVISIONS MIGRATORY BIRD SUBSISTENCE HARVEST IN ALASKA General Regulations Governing Subsistence Harvest § 92.22 Subsistence migratory bird species. You may harvest birds or...

  9. 50 CFR 20.42 - Transportation of birds of another.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Transportation of birds of another. 20.42... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Transportation Within the United States § 20.42 Transportation of birds of another. No person shall transport migratory game birds belonging to another...

  10. 9 CFR 82.15 - Replacement birds and poultry.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Replacement birds and poultry. 82.15... CHLAMYDIOSIS Newcastle Disease § 82.15 Replacement birds and poultry. Birds and poultry that have been destroyed because of a quarantine for Newcastle disease may not be replaced by birds or poultry...

  11. 14 CFR 25.631 - Bird strike damage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird...

  12. 50 CFR 20.20 - Migratory Bird Harvest Information Program.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... provided at 50 CFR 2.1(b). (b) General provisions. Each person hunting migratory game birds in any State... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Migratory Bird Harvest Information Program... IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Taking § 20.20 Migratory Bird...

  13. 50 CFR 20.20 - Migratory Bird Harvest Information Program.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Migratory Bird Harvest Information Program... IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Taking § 20.20 Migratory Bird Harvest... information will be used to provide a sampling frame for the national Migratory Bird Harvest Survey....

  14. 14 CFR 25.631 - Bird strike damage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird...

  15. 50 CFR 20.37 - Custody of birds of another.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Custody of birds of another. 20.37 Section... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Possession § 20.37 Custody of birds of another. No person shall receive or have in custody any migratory game birds belonging to another person unless...

  16. 50 CFR 92.22 - Subsistence migratory bird species.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Subsistence migratory bird species. 92.22... (CONTINUED) MISCELLANEOUS PROVISIONS MIGRATORY BIRD SUBSISTENCE HARVEST IN ALASKA General Regulations Governing Subsistence Harvest § 92.22 Subsistence migratory bird species. You may harvest birds or...

  17. 50 CFR 20.38 - Possession of live birds.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Possession of live birds. 20.38 Section 20... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Possession § 20.38 Possession of live birds. Every migratory game bird wounded by hunting and reduced to possession by the hunter shall be immediately...

  18. 14 CFR 25.631 - Bird strike damage.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Bird strike damage. 25.631 Section 25.631... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.631 Bird strike damage. The... airplane after impact with an 8-pound bird when the velocity of the airplane (relative to the bird...

  19. 50 CFR 20.38 - Possession of live birds.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Possession of live birds. 20.38 Section 20... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Possession § 20.38 Possession of live birds. Every migratory game bird wounded by hunting and reduced to possession by the hunter shall be immediately...

  20. 50 CFR 20.62 - Importation of birds of another.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Importation of birds of another. 20.62... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Importations § 20.62 Importation of birds of another. No person shall import migratory game birds belonging to another person....