Records |
Author |
|
Title |
Are stress hormone levels a good proxy of foraging success? An experiment with king penguins, Aptenodytes patagonicus.
|
Type |
Journal Article |
Year |
2009 |
Publication |
The Journal of experimental biology |
Abbreviated Journal |
J. Exp. Biol. |
Volume |
212 |
Issue |
17 |
Pages |
2824 -9 |
Keywords |
Animals, Body Composition, Corticosterone, Corticosterone: blood, Eating, Feeding Behavior, Female, Male, Spheniscidae, Spheniscidae: anatomy & histology, Spheniscidae: metabolism, Spheniscidae: physiology, |
Abstract |
In seabirds, variations in stress hormone (corticosterone; henceforth CORT) levels have been shown to reflect changing marine conditions and, especially, changes in food availability. However, it remains unclear how CORT levels can be mechanistically affected by these changes at the individual level. Specifically, the influence of food acquisition and foraging success on CORT secretion is poorly understood. In this study, we tested whether food acquisition can reduce baseline CORT levels (;the food intake hypothesis') by experimentally reducing foraging success of King Penguins (Aptenodytes patagonicus). Although CORT levels overall decreased during a foraging trip, CORT levels did not differ between experimental birds and controls. These results demonstrate that mass gain at sea is not involved in changes in baseline CORT levels in this species. The overall decrease in CORT levels during a foraging trip could result from CORT-mediated energy regulation (;the energy utilisation hypothesis'). Along with other evidence, we suggest that the influence of foraging success and food intake on CORT levels is complex and that the ecological meaning of baseline CORT levels can definitely vary between species and ecological contexts. Therefore, further studies are needed to better understand (1) how baseline CORT levels are functionally regulated according to energetic status and energetic demands and (2) to what extent CORT can be used to aid in the conservation of seabird populations.
|
Programme |
109;394 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-0949 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2217 |
Permanent link to this record |
|
|
|
Author |
Loots Christophe, Swadling Kerrie M, Koubbi Philippe, |
Title |
|
Type |
Journal Article |
Year |
2009 |
Publication |
Journal of Marine Systems |
Abbreviated Journal |
|
Volume |
78 |
Issue |
4 |
Pages |
599 -605 |
Keywords |
Paralabidocera antarctica, Drescheriella glacialis, Stephos longipes, Southern Ocean, Sea ice, Life cycles, |
Abstract |
|
Programme |
1142 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0924-7963 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2266 |
Permanent link to this record |
|
|
|
Author |
|
Title |
Metabolic rate throughout the annual cycle reveals the demands of an Arctic existence in Great Cormorants
|
Type |
Journal Article |
Year |
2011 |
Publication |
Ecology |
Abbreviated Journal |
Ecology |
Volume |
92 |
Issue |
2 |
Pages |
475 -486 |
Keywords |
arctic, basal metabolic rate, catch per unit effort, cpue, daily energy expenditure, day length, diving depths, field metabolic rate, foraging efficiency, great cormorant, greenland, phalacrocorax carbo, seasonal variation, |
Abstract |
Aquatic endotherms living in polar regions are faced with a multitude of challenges, including low air and water temperatures and low illumination, especially in winter. Like other endotherms from cold environments, Great Cormorants (Phalacrocorax carbo) living in Arctic waters were hypothesized to respond to these challenges through a combination of high daily rate of energy expenditure (DEE) and high food requirements, which are met by a high rate of catch per unit effort (CPUE). CPUE has previously been shown in Great Cormorants to be the highest of any diving bird. In the present study, we tested this hypothesis by making the first measurements of DEE and foraging activity of Arctic-dwelling Great Cormorants throughout the annual cycle. We demonstrate that, in fact, Great Cormorants have surprisingly low rates of DEE. This low DEE is attributed primarily to very low levels of foraging activity, particularly during winter, when the cormorants spent only 2% of their day submerged. Such a low level of fo...
|
Programme |
388 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
Ecological Society of America |
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0012-9658 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2372 |
Permanent link to this record |
|
|
|
Author |
|
Title |
The relationship between sea surface temperature and population change of Great Cormorants Phalacrocorax carbo breeding near Disko Bay, Greenland
|
Type |
Journal Article |
Year |
2011 |
Publication |
Ibis |
Abbreviated Journal |
Ibis (Lond. 1859) |
Volume |
153 |
Issue |
1 |
Pages |
170 -174 |
Keywords |
Arctic warming, climate change, diving, Phalacrocorax, thermoregulation, vision, |
Abstract |
Arctic seas have warmed and sea ice has retreated. This has resulted in range contraction and population declines in some species, but it could potentially be a boon for others. Great Cormorants Phalacrocorax carbo have a partially wettable plumage and seem poorly suited to foraging in Arctic waters. We show that rates of population change of Cormorant colonies around Disko Bay, Greenland, are positively correlated with sea surface temperature, suggesting that they may benefit from a warming Arctic. However, although Cormorant populations may increase in response to Arctic warming, the extent of expansion of their winter range may ultimately be limited by other factors, such as sensory constraints on foraging behaviour during long Arctic nights.
|
Programme |
388 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
Blackwell Publishing Ltd |
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1474-919X |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2374 |
Permanent link to this record |
|
|
|
Author |
Picard G, Domine F, Krinner G, Arnaud L, Lefebvre E, |
Title |
Inhibition of the positive snow-albedo feedback by precipitation in interior Antarctica |
Type |
Journal |
Year |
2012 |
Publication |
Nature Climate Change |
Abbreviated Journal |
|
Volume |
|
Issue |
11 |
Pages |
795-798 |
Keywords |
limate change Cryospheric science |
Abstract |
|
Programme |
1013 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
Nature Publishing Group |
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1758-6798 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
456 |
Permanent link to this record |
|
|
|
Author |
|
Title |
Candidate models for the IGRF 11th generation making use of extrapolated observatory data
|
Type |
Journal Article |
Year |
2010 |
Publication |
Earth Planets and Space |
Abbreviated Journal |
|
Volume |
62 |
Issue |
|
Pages |
745 -751 |
Keywords |
|
Abstract |
Three candidate models are produced in response to the call for IGRF-11 models. A main field model around epoch 2005.0 is based on one year of Oersted and CHAMP measurements, and is proposed for the definitive model for epoch 2005.0. A main field model around epoch 2009.5, based on two months of CHAMP measurements and extrapolated to 2010.0, is proposed as a main field model for epoch 2010.0. A secular variation model valid for 2010.0-2015.0, based on the extrapolation through exponential
smoothing of observatory monthly mean values, is proposed as a predictive secular variation model. Comparison of similar extrapolations made for previous IGRF generations with actual observations are presented and discussed. |
Programme |
139;905 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1343-8832 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2464 |
Permanent link to this record |
|
|
|
Author |
|
Title |
Continuous 25-yr aerosol records at coastal Antarctica I: inter-annual variability of ionic compounds and links to climate indices |
Type |
Journal Article |
Year |
2011 |
Publication |
Tellus B |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
|
Abstract |
|
Programme |
414 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
Blackwell Publishing Ltd |
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1600-0889 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2549 |
Permanent link to this record |
|
|
|
Author |
Jaffal A, Paris-Palacios S, Jolly S, Thailly A F, Delahaut L, Beall E, Roche H, Biagianti-Risbourg S, Betoulle S, |
Title |
Cadmium and copper contents in a freshwater fish species (brook trout, Salvelinus fontinalis) from the subantarctic Kerguelen Islands
|
Type |
Journal Article |
Year |
2011 |
Publication |
Polar Biology |
Abbreviated Journal |
Polar Biol. |
Volume |
34 |
Issue |
3 |
Pages |
397 -409 |
Keywords |
|
Abstract |
The subantarctic Kerguelen Islands (49 degrees S, 70 degrees E) contain freshwaters among the most isolated in the world from direct human activities. Cadmium and copper concentrations were analyzed in muscle and liver tissues of 57 non-migratory brook trout (Salvelinus fontinalis) inhabiting the Sud River of Kerguelen Islands. The mean cadmium concentration in liver was 1.13 mu g/g dry wt, within the range of levels measured in liver of marine fish from the Southern Ocean. Muscular Cd levels (0.12 mu g/g dry wt) were roughly ten times higher than those measured in Kerguelen's marine fish species. Copper levels were very high in the two organs (62.27 mu g/g dry wt in liver and 3.02 mu g/g dry wt in muscle) compared to those detected in fish from the Southern Ocean. Regarding the seasonal trend, the highest Cu and Cd muscular levels were measured in fish at the end of the austral winter, whereas the highest hepatic levels were observed at the end of the austral summer. Moreover, hepatic cadmium levels were higher in females than in males. These results could be related to brook trout spawning physiological preparations and foraging behavior during the summer period. We provide here the first results about Cu and Cd levels in liver and muscle of a freshwater fish species in an insular subantarctic context. They are in agreement with the high cadmium contamination found in fish of the Southern Ocean.
|
Programme |
409;1041 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0722-4060 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2620 |
Permanent link to this record |
|
|
|
Author |
|
Title |
First Report of Nasturtium as a Natural Host of Cherry leaf roll virus on Amsterdam Island
|
Type |
Journal Article |
Year |
2010 |
Publication |
PLANT DISEASE |
Abbreviated Journal |
Plant Dis. |
Volume |
94 |
Issue |
|
Pages |
477 |
Keywords |
|
Abstract |
Cherry leaf roll virus (CLRV) is a well-known virus belonging to the genus Nepovirus, but unlike most members of this genus, it is not known to be transmitted by nematodes but only through seeds and pollen. Since its first description in 1955 on Prunus avium L. in England (1), CLRV has been shown to have a worldwide distribution and a wide natural host range. During a survey of plant viruses in the French sub-Antarctic islands, samples from nasturtium plants (Tropaeolum majus), an introduced plant species, showing symptoms of leaf mosaic, deformation, and veinal necrosis were collected on Amsterdam Island. Upon mechanical transmission with sap extracts, necrotic ringspot and oak-leaf symptoms typical of Nepovirus infection were observed on the leaves of inoculated Nicotiana clevelandii and N. tabacum plants. Inoculation of healthy nasturtium plants resulted in mosaic and pin-point necrosis symptoms. Electron microscopy on negatively stained sap extracts revealed the presence of icosahedral virions, 28 to ...
|
Programme |
136 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
The American Phytopathological Society |
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0191-2917 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2661 |
Permanent link to this record |
|
|
|
Author |
|
Title |
Introduced black rats Rattus rattus on Ile de la Possession (Iles Crozet, Subantarctic): diet and trophic position in food webs
|
Type |
Journal Article |
Year |
2011 |
Publication |
Polar Biology |
Abbreviated Journal |
Polar Biol. |
Volume |
34 |
Issue |
2 |
Pages |
169-180 -180 |
Keywords |
Biomedical and Life Sciences, |
Abstract |
Rats introduced on islands can affect ecosystem structure and function by feeding on terrestrial plants and both marine and terrestrial animals. The diet and trophic position of Rattus rattus introduced on Ile de la Possession (Iles Crozet) was assessed from two sites, according to the presence or absence of a king penguin colony. We used three complementary assays: macroanalyses of the stomach, faecal microhistology, and stable isotope analyses of 15N/13C in liver. Near the rookery, spermatophytes contributed on average 50% (confidential interval: 2375) to the diet based on isotopes, mainly consisting in reproductive parts of Poa spp., Agrostis magellanica, and Cerastium fontanum identified in faeces. Terrestrial animal preys were represented by insects that contributed 25% (056) in isotopes, dominated in faeces by caterpillars of Pringleophaga spp. and adult weevils. Bird remains were found in faeces, forming 18% (630) of isotopes. Terrestrial earthworms contributed to 7% (021), with chaetae observed in faeces. On the other site, spermatophytes represented 62% (5173) of assimilated food in rats livers, mainly formed by Poaceae and Acaena magellanica, insects by caterpillars [24% (1039)], and terrestrial earthworms [13% (223)]. Our results suggest that rats, which were found at the top of terrestrial food chains, may have a direct role on a such simplified ecosystem, by preying on the most abundant and largest body-sized terrestrial invertebrates,e.g. the keystone species Pringleophaga spp., and by feeding on both reproductive and vegetative parts of autochthonous and introduced plants. The discrepancies and usefulness of employing both isotopes and faecal analyses are discussed. |
Programme |
136 |
Campaign |
|
Address |
|
Corporate Author |
|
Thesis |
Bachelor's thesis |
Publisher |
Springer Berlin / Heidelberg |
Place of Publication |
|
Editor |
|
Language |
|
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0722-4060 |
ISBN |
|
Medium |
|
Area |
|
Expedition ![sorted by Expedition field, descending order (down)](img/sort_desc.gif) |
|
Conference |
|
Notes |
|
Approved |
yes |
Call Number |
|
Serial |
2671 |
Permanent link to this record |