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Climate is altering rapidly in parts of the Arctic and Antarctic but we know little about how marine organisms are responding to, or might respond to such changes. Knowledge of within-taxon variability is the vital context (currently missing) to interpretation of environmental signals. We investigated growth in six species and three genera of erect Antarctic bryozoans, an ideal model taxon to investigate such response. Cellarinella margueritae, C. nodulata, C. rogickae, C. watersi, Melicerita obliqua and Stomhypselosaria watersi, extended 3.4, 5.2, 4.6, 4.1, 4.9 and 4.5 mm year(-1) and synthesised 24, 55, 45, 176, 34 and 46 mg CaCO3 year(-1), respectively. The maximum ages of these species ranged from 11 to 15 years except M. obliqua, which reached 32 years. This is the first investigation of growth rates of closely related Antarctic invertebrate species and reports the slowest growth rates of bryozoans known from anywhere to date. Our data coupled with that from literature shows that Antarctic bryozoan growth varies << 10(1) between species, 10(1) between genera, 10(2) between morphologies and is similar to 10(1) slower than in tropical or temperate regions. However, within encrusting types the slowest growing species grow at similar rates from poles to tropics. Age was a strong confounding factor across our Antarctic study species but age-standardised data showed a possible decline in annual growth from 1992 to 2003. We identify several factors increasing this environmental signal strength, including (1) the importance of generic (though not necessarily species) identification and (2) use of dry-mass or ash-free dry-mass as the measures of growth.

Responses by marine top predators to environmental variability have previously been almost impossible to observe directly. By using animal-mounted instruments simultaneously recording movements, diving behavior, and in situ oceanographic properties, we studied the behavioral and physiological responses of southern elephant seals to spatial environmental variability throughout their circumpolar range. Improved body condition of seals in the Atlantic sector was associated with Circumpolar Deep Water upwelling regions within the Antarctic Circumpolar Current, whereas High-Salinity Shelf Waters or temperature/salinity gradients under winter pack ice were important in the Indian and Pacific sectors. Energetic consequences of these variations could help explain recently observed population trends, showing the usefulness of this approach in examining the sensitivity of top predators to global and regional-scale climate variability.

Six out of ten adult Ross seals that were tagged with Argos satellite-linked dive recorders off Queen Maud Land, just after the moult in February, provided data on location and diving activity throughout a year. Shortly after tagging, the animals headed 2,000 km north and stayed pelagic in the area south of the Antarctic Polar Front, until October when they went south into the pack-ice. Throughout the year they made about 100 dives a day, most to a depth of 100–300 m, the deepest dive on record being 792 m, while some dives were very shallow during their stay in the pack-ice. Most dives, outside the breeding and moulting period, lasted for 5–15 min throughout the year. This diving behaviour is consistent with feeding on mid-water fish, like Pleurogramma antarcticum, squid, and to some extent krill (Euphausia superba), when in the pack-ice, and myctophid fish and several species of squid, when in the open ocean. The nursing period was 13 days in mid-November, and moulting occurs in late January–early February, which is the period when sightings surveys for this species should be done.

We examined deep-sea benthic data on polychaetes, isopods and bivalves from the Atlantic sector of the Southern Ocean. Samples were taken during the expeditions EASIZ II (1998), ANDEEP I and II (2002) (depth: 742-6,348 m). The range between sites varies from 3 to 1,900 km. Polychaetes (175 species in total) and isopods (383 species) had a high proportion of species restricted to one or two sites (72 and 70%, respectively). Bivalves (46 species) had a higher proportion of species represented at more sites. Beta diversity (Whittaker and Jaccard) was higher for polychaetes and isopods than for bivalves. The impact of depth on species richness was not consistent among groups; polychaetes showed a negative relationship to depth, isopods displayed highest richness in the middle depth range (2,000-4,000 m), whereas bivalves showed no clear relationship to depth. Species richness was not related to latitude (58-74 degrees S) or longitude (22-60 degrees W) for any group.

Dynamic behaviour of the West Antarctic ice sheet in the Amundsen Sea Embayment during the later quaternary climatic cycles, pliocene to quaternary palaeoceanography in the Southwest Pacific, and holocene climate history of Maxwell Bay, King George Island.

The termination of the last ice age (Termination 1; T1) is crucial for our understanding of global climate change and for the validation of climate models. There are still a number of open questions regarding for example the exact timing and the mechanisms involved in the initiation of deglaciation and the subsequent interhemispheric pattern of the warming. Our study is based on a well-dated and high-resolution alkenone-based sea surface temperature (SST) record from the SE-Pacific off southern Chile (Ocean Drilling Project Site 1233) showing that deglacial warming at the northern margin of the Antarctic Circumpolar Current system (ACC) began shortly after 19,000 years BP (19 kyr BP). The timing is largely consistent with Antarctic ice-core records but the initial warming in the SE-Pacific is more abrupt suggesting a direct and immediate response to the slowdown of the Atlantic thermohaline circulation through the bipolar seesaw mechanism. This response requires a rapid transfer of the Atlantic signal to the SE-Pacific without involving the thermal inertia of the Southern Ocean that may contribute to the substantially more gradual deglacial temperature rise seen in Antarctic ice-cores. A very plausible mechanism for this rapid transfer is a seesaw-induced change of the coupled ocean–atmosphere system of the ACC and the southern westerly wind belt. In addition, modelling results suggest that insolation changes and the deglacial CO2 rise induced a substantial SST increase at our site location but with a gradual warming structure. The similarity of the two-step rise in our proxy SSTs and CO2 over T1 strongly demands for a forcing mechanism influencing both, temperature and CO2. As SSTs at our coring site are particularly sensitive to latitudinal shifts of the ACC/southern westerly wind belt system, we conclude that such latitudinal shifts may substantially affect the upwelling of deepwater masses in the Southern Ocean and thus the release of CO2 to the atmosphere as suggested by the conceptual model of [Toggweiler, J.R., Rusell, J.L., Carson, S.R., 2006. Midlatitude westerlies, atmospheric CO2, and climate change during ice ages. Paleoceanography 21. doi:10.1029/2005PA001154].

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.