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As a result of intensive field activities carried out by several nations over the past 15 years, a set of accumulation measurements for western Dronning Maud Land, Antarctica, was collected, based on firn-core drilling and snow-pit sampling. This new information was supplemented by earlier data taken from the literature, resulting in 111 accumulation values. Using Geographical Information Systems software, a first region-wide mean annual snow-accumulation field was derived. In order to define suitable interpolation criteria, the accumulation records were analyzed with respect to their spatial autocorrelation and statistical properties. The resulting accumulation pattern resembles well- known characteristics such as a relatively wet coastal area with a sharp transition to the dry interior, but also reveals complex topographic effects. Furthermore, this work identifies new high-return shallowdrilling sites by uncovering areas of insufficient sampling density.

Siste halvdel av 1950-tallet var en viktig periode i norsk hvalfangst. Norge, som tidligere hadde vært den dominerende hvalfangstnasjonen, var som resultat av hard konkurranse kommet på defensiven i forhold til de andre hvalfangstnasjonene. Den høye hvaloljeprisen, som blant annet var forårsaket av Europas fettbehov i kjølvannet av den andre verdenskrig, resulterte i at nye nasjoner etter krigen engasjerte seg i hvalfangst. For å sikre seg en størst mulig andel av totalkvoten ønsket Sovjetunionen og Japan nå å foreta en kraftig utbygging av sine fangstflåter, noe som ville gjøre situasjonen enda vanskeligere for den norske hvalfangstnæringen. Det var av største viktighet at denne ekspansjonen ble stoppet, siden dette spørsmålet i norske hvalfangstkretser ble oppfattet som et være eller ikke være for norsk hvalfangst. De norske hvalfangstselskapene startet derfor en kampanje for å få regjeringen til å stanse de to landenes utbyggingsplaner. Mitt hovedfokus i denne oppgaven vil være å belyse hvalfangstnæringens rolle i utformingen av den norske hvalfangstpolitikken på 1950-tallet. For å kunne gi et svar på dette spørsmålet har jeg tatt for meg to av hvalfangstpolitikkens viktigste saker dette tiåret. Den første dreier seg om den nevnte kampen for å stanse Sovjetunionens og Japans ekspansjonsplaner, mens den andre dreier seg om kampen for en ordning med nasjonale kvoter. En studie av disse to sakene gir også innsyn i næringen som helhet. I tillegg til å kartlegge hvalfangstnæringens politiske innflytelse vil det også være viktig å gi en fremstilling av utviklingen innen hvalfangstreguleringen i denne perioden, altså siste halvdel av 1950-tallet. Med begrepet norsk hvalfangstpolitikk, mener jeg den politikken regjeringen utformet og som blant annet ble presentert på de årlige møtene i Den internasjonale hvalfangskommisjonen (IWC). For å kunne gi et godt svar på problemstillingen er det nødvendig å besvare flere underliggende spørsmål. Hvalfangstselskapene organiserte seg tidlig gjennom dannelsen av Norges Hvalfangstforbund. Dette var en organisasjon som kjempet for at hvalfangstredernes interesser ble ivaretatt. Hvalfangstrederne var i tillegg representert i Hvalrådet. Dette var et statlig organ som hadde en rådgivende funksjon i regjeringens utarbeidelse av den norske hvalfangstpolitikken. Følgende spørsmål blir derfor viktige i mitt arbeid: Hvilken rolle spilte Norges Hvalfangstforbund i utformingen av den norske hvalfangstpolitikken? Hvordan opererte næringens representanter for å få gjennomslag for sine interesser i Hvalrådet? Det vil også være nødvendig å kartlegge sammenhengen mellom Hvalrådet og regjeringen. I hvilken grad var Hvalrådets uttalelser utslagsgivende for den endelige norske hvalfangstpolitikken? Bortsett fra tiden da Norge stod utenfor Den internasjonale hvalfangstkonvensjonen, sendte landet hvert år en delegasjon til kommisjonens årlige møter. Det vil være viktig å undersøke i hvilken grad næringen var representert i disse delegasjonene. Møtte den norske delegasjonen med bundet mandat, eller hadde den en viss frihet til å forhandle? Mot slutten av oppgaven ønsker jeg å se komparativt på hvalfangstnæringens politiske innflytelse i forhold til landbruket og fiskerinæringen i den samme perioden. Oppnådde hvalfangstnæringen større politisk innflytelse sammenliknet med disse næringene, og hva skyldtes i tilfelle dette?

Macrobenthic soft-bottom molluscs were sampled in 30 stations located in the Bellingshausen Sea at depths ranging from 90 to 3304 m. The samples were collected using a quantitative grab box-corer during the cruises BENTART 03, from 24 January to 3 March 2003, and BENTART 06, from 2 January to 16 February 2006. Molluscs represent 1074 specimens belonging to 62 species of Polyplacophora, Gastropoda, Bivalvia and Scaphopoda. The bivalve Cyamiocardium denticulatum was the most abundant species (448 specimens). The abundance per station varied between 1 and 446 specimens. The Shannon–Wiener diversity index ranged between one specimen and 2.36, the Pielou evenness index ranged between 0.00 and 1 and species richness ranged from 1 to 14 species. Diversity showed great variations at different stations. After multivariate analysis (cluster analysis and nonmetrical multidimensional scaling) based on Bray–Curtis similarities, we were able to separate two principal clusters. The first cluster groups together species from shallower bottoms near Peter I Island and the Antarctic Peninsula, and the second cluster groups together species from deeper bottoms in the Bellingshausen Sea. The combination of environmental variables with the highest correlations with faunistic data was that of depth and coarse sand at the surface.

Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth’s climate dynamics. For the last glacial period, ice core studies1,2 have revealed strong coupling of the largest millennial-scale warm events in Antarctica with the longest Dansgaard–Oeschger events in Greenland3,4,5 through the Atlantic meridional overturning circulation6,7,8. It has been unclear, however, whether the shorter Dansgaard–Oeschger events have counterparts in the shorter and less prominent Antarctic temperature variations, and whether these events are linked by the same mechanism. Here we present a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records. After methane synchronization with an ice core from North Greenland9, the oxygen isotope record from the Dronning Maud Land ice core shows a one-to-one coupling between all Antarctic warm events and Greenland Dansgaard–Oeschger events by the bipolar seesaw6. The amplitude of the Antarctic warm events is found to be linearly dependent on the duration of the concurrent stadial in the North, suggesting that they all result from a similar reduction in the meridional overturning circulation.

In 1970 the fourth and final volume of Arne Odd Johnsen and Joh. N. Tønnessens’s Den moderne hvalfangsts historie was published. The work represented a milestone in the writing about the development of the 20th century whaling industry. This paper reviews the literature that has been published in Norway and internationally on the history of modern whaling after Johnsen and Tønnessen, and analyses the focus, trends and direction in the research and writing on whaling history in the period.

Different organochlorine compounds (OCs) were measured in the blood of breeding south polar skuas (Catharacta maccormicki) at Svarthamaren, Dronning Maud Land (Antarctica) and compared to those in two species of northern hemisphere gulls:  the Arctic glaucous gull (Larus hyperboreus) and the subarctic great black-backed gull (Larus marinus). The skuas had 8% and 29% of the ∑OC levels (45 ng/g, wet weight) of glaucous gulls (591 ng/g) and great black-backed gulls (158 ng/g), respectively. Polychlorinated biphenyls (PCBs) and p,p‘-dichlorodiphenyldichloroethylene (p,p‘-DDE) were very low in skuas compared to northern gulls, but the mean hexachlorobenzene (HCB) level was 1.7 times higher than in great black-backed gulls and one-third of the glaucous gull level. Mirex levels in skuas were among the highest reported in birds, the mean level being 3 and 26 times higher than those in glaucous gull and great black-backed gulls, respectively. In skuas, the mean levels of HCB, oxychlordane, p,p‘-DDE, and PCBs increased by about 30% during a 2-week period, and mirex increased by nearly 60%. In glacuous gulls, HCB, p,p‘-DDE, and PCBs increased by 10−20%. For HCB, mirex, and oxychlordane, only a relatively small proportion of the increase in skuas could be explained by changes in lipid pools and the levels at first sampling, compared to glaucous gulls. Thus, skuas were probably accumulating these compounds when present in Antarctica. p,p‘-DDE and PCB levels, in contrast, seemed much more stable in the skuas. Relatively high levels of mirex and HCB in south polar skuas are concerning with regard to potential adverse effects.

The seasonal haul-out pattern of itinerant male Antarctic fur seals (Arctocephalus gazella) was determined by regular counts at Mossman Peninsula, Laurie Island, South Orkney Islands, from 1996 to 2005. Small numbers of animals began to arrive at the beach in late December / early January (mean date 28 December ± 15 days, n = 10). Peak numbers of animals ashore changed considerably between seasons. In 1996, 1998 and 2001, peak numbers were registered in March (6/3, 18/3 and 6/3, respectively). Numbers peaked in 1997, 1999 and 2005 at the end of January / beginning of February (26/1, 2/2 and 28/1, respectively). In 2000, 2002, 2003 and 2004 peaks were registered in the third week of February (15/2, 22/2, 14/2 and 20/2, respectively). Peaks in numbers of seals ashore also varied between years, being minimum during 2001 (2531 individuals) and maximum during 2006 (16 610 individuals). In March 1998 the coasts of Laurie Island were surveyed by navigating inflatable boats near the shoreline; 18 haul-out places were identified. The big differences in peak numbers, as well as in the dates of peak events among years, suggest that local conditions could have an effect on the numbers of animals hauled out in a given year. It may therefore be difficult to predict trends from summer censuses in non-breeding places.

In hierarchical patch systems, small-scale patches of high density are nested within large-scale patches of low density. The organization of multiple-scale hierarchical systems makes non-random strategies for dispersal and movement particularly important. Here, we apply a new method based on first-passage time on the pathway of a foraging seabird, the Antarctic petrel (Thalassoica antarctica), to quantify its foraging pattern and the spatial dynamics of its foraging areas. Our results suggest that Antarctic petrels used a nested search strategy to track a highly dynamic hierarchical patch system where small-scale patches were congregated within patches at larger scales. The birds searched for large-scale patches by traveling fast and over long distances. Once within a large-scale patch, the birds concentrated their search to find smaller scale patches. By comparing the pathway of different birds we were able to quantify the spatial scale and turnover of their foraging areas. On the largest scale we found foraging areas with a characteristic scale of about 400 km. Nested within these areas we found foraging areas with a characteristic scale of about 100 km. The large-scale areas disappeared or moved within a time frame of weeks while the nested small-scale areas disappeared or moved within days. Antarctic krill (Euphausia superba) is the dominant food item of Antarctic petrels and we suggest that our findings reflect the spatial dynamics of krill in the area.