A detailed study was made of the extent of genetic variation within populations of two moss species, Bryum argenteum and Hennediella heimii, from the Garwood Valley in Southern Victoria Land, Antarctica. RAPD (Random Amplified Polymorphic DNA) technology was used to analyse over 30 clumps of each species, collected from adjacent sites in five small meltstream drainage channels. Overall, extensive genetic variation was found, with no two samples being identical in either species. For both species, most clumps showed within-clump variation, although generally the shoots from each clump were most closely related to other shoots from that clump, indicating somatic mutation. Of the B. argenteum isolates, most showed distinct clustering corresponding to the five drainage channels, with some clustering within the top, middle or bottom of the channels, and separation of northern and southern sides of the valley. There was some evidence of across-channel dispersal for B. argenteum. For H. heimii, the situation was quite different; there was very little clustering of clumps according to channel from which they were collected. Rather, the isolates appeared to form one continuous population across the five channels, with partial separation of northern and southern sides of the valley. These results are consistent with the predicted means of dispersal of these species in Antarctica: predominantly by water for B. argenteum, and by wind for H. heimii.

Primary, tail and body moult of three seabirds from Tristan da Cunha archipelago were studied by castnetting offshore south Brazil from February 2006 to August 2007. Timing, duration and synchronization of primary and tail moult are described relative to the annual calendar. Body moult overlapped breeding in Atlantic yellow-nosed albatrosses (Thalassarche chlororhynchos), but tail and primary moult did not. Spectacled petrels (Procellaria conspicillata) had protracted body moult, whereas primary and tail moult were completed by August. We documented onset of primary moult during chick-rearing in spectacled petrels and great shearwaters (Puffinus gravis) of unknown breeding status, and suggest that the south-west Atlantic Ocean holds important numbers of moulting birds of both species during the summer–early autumn. The albatrosses and the spectacled petrels replaced rectrices alternately. Great shearwaters replaced rectrices outward, starting at the central pair. Primary, tail and body moult largely overlap in all three species, suggesting that the metabolic costs of primary moult may not be overly restrictive. Metabolic and nutritional ability to afford simultaneous moult of different feather tracts support the idea that impaired flight caused by wing moult is a strong factor driving no overlap of primary moult and breeding.

Several factors threaten populations of albatrosses and giant petrels, including the impact of fisheries bycatch and, at some colonies, predation from introduced mammals. We undertook population monitoring on Gough Island of three albatross species (Tristan albatross Diomedea dabbenena L., sooty albatross Phoebetria fusca Hilsenberg, Atlantic yellow-nosed albatross Thalassarche chlororhynchos Gmelin) and southern giant petrels Macronectes giganteus (Gmelin). Over the study period, numbers of the Critically Endangered Tristan albatross decreased at 3.0% a year. Breeding success for this species was low (23%), and in eight count areas was correlated (r2 = 0.808) with rates of population decline, demonstrating chick predation by house mice Mus musculus L. is driving site-specific trends and an overall decline. Numbers of southern giant petrels were stable, contrasting with large increases in this small population since 1979. Significant population declines were not detected for either the Atlantic yellow-nosed or sooty albatross, however, caution should be applied to these results due to the small proportion of the population monitored (sooty albatross) and significant interannual variation in numbers. These trends confirm the Critically Endangered status of the Tristan albatross but further information, including a more accurate estimate of sooty albatross population size, is required before determining island wide and global population trends of the remaining species.

Since the Last Glacial Maximum, ice has retreated through the fjords of the South Shetland Islands leaving a valuable record of submarine landforms behind. In this study, glacial landforms and sub-bottom characteristics have been mapped to investigate the late Holocene retreat behaviour of the Fourcade Glacier and to delineate past environmental processes in Potter Cove, King George Island. The comprehensive datasets include high-resolution swath bathymetry, shallow seismic profiling and one sediment core. Moraines, moraine incisions and glacial lineations were mapped on the sea floor in the inner part of the cove, whereas pockmarks, ice scour marks and channel structures were identified in the outer part. Sub-bottom characteristics have been assigned to different acoustic facies types indicating different depositional settings. The results reveal glacial recessions as well as stillstands and potential readvances during the late Holocene. Furthermore, the sediment record indicates that the Fourcade Glacier was situated inside the inner cove during the Little Ice Age (500–100 cal yr bp).

The breeding season diet of the three surface-nesting petrel species on the Rauer Islands, Prydz Bay were examined. The stomach contents of cape petrel (Daption capense), Antarctic petrel (Thalassoica antarctica), and southern fulmar (Fulmarus glacialoides) were sampled by collecting regurgitates and by stomach flushing during the 1987/88 early chick-rearing period. Pleuragramma antarcticum and Euphausia superba dominated the diets of all species. By mass they constituted 78% and 22% of Antarctic petrel diet, 63% and 36% of southern fulmar diet, and 14% and 85% of cape petrel diet respectively. P. antarcticum increased in importance in the diet of Antarctic petrels during the course of the study, while E. superba became increasingly important in the diets of southern fulmars and cape petrels. Previous studies conducted during incubation consistently reported the diets as comprising chiefly cephalopods and euphausiids, whilst studies during chick-rearing have reported fish and euphausiids dominating, and very little cephalopod material.

A dramatic reduction in catch rates of Antarctic toothfish in McMurdo Sound, Antarctica, has led to conclusions that the commercial bottom longline fishery for toothfish in the Ross Sea has drastically altered the toothfish population with cascading effects on the McMurdo Sound ecosystem. However, results from a new monitoring programme for Antarctic toothfish and other top predators carried out in McMurdo Sound in 2014 have shown toothfish catch rate, fish size and fish age similar to those observed prior to 2002. These results suggest that either large and old fish have returned to McMurdo Sound following a temporary environmentally driven absence or that they remained locally present but were not detected in the areas sampled. These findings highlight the importance of continued standardized monitoring for detecting the potential effects of fishing on the Ross Sea ecosystem.

The occurrence of dry permafrost overlying ice-rich permafrost is unique to the Antarctic Dry Valleys on Earth and to the high latitudes of Mars. The stability and distribution of this ice are poorly understood and fundamental to understanding the Antarctic climate as far back as a few million years. Polygonal patterned ground is nearly ubiquitous in these regions and is integrally linked to the history of the icy permafrost and climate. We examined the morphology of polygonal ground in Beacon Valley and the Beacon Heights region of the Antarctic Dry Valleys, and show that polygon size is correlated with ice-table depth (the boundary between dry and ice-rich permafrost). A numerical model of seasonal stress in permafrost shows that the ice-table depth is a dominant factor. Remote sensing and field observations of polygon size are therefore important tools for investigating subsurface ice. Polygons are long-lived landforms and observed characteristics indicate no major fluctuations in the ice-table depth during their development. We conclude that the Beacon Valley and Beacon Heights polygons have developed for at least 104 years to achieve their present mature-stage morphology and that the ice-table depth has been stable for a similar length of time.

This article reviews the adequacy of data and models currently being used to estimate the present and future population sizes of the Antarctic toothfish (Dissostichus mawsoni Norman) in the Ross Sea regional ecosystem. The current tagging programme is unlikely to provide an accurate picture of total population size, and estimates of both the pre-exploitation spawning stock biomass and the ratio of current to pre-exploitation biomass are unreliable. Many parameters necessary for estimating future population growth or decline have not been measured, and the current objective of a 50% reduction in biomass relative to unexploited biomass may easily fail to prevent a much larger reduction from taking place. The need to guess values of important parameters makes it impossible to set bounds on the potential errors of population forecasts. Current scientific knowledge is far from what is needed to predict the likely effects of food-web responses to harvesting of toothfish in the Ross Sea, or to predict the feedback effects of those food-web changes on toothfish populations.

Western Wright Valley, from Wright Upper Glacier to the western end of the Dais, can be divided into three broad geomorphic regions: the elevated Labyrinth, the narrow Dais which is connected to the Labyrinth, and the North and South forks which are bifurcated by the Dais. Soil associations of Typic Haplorthels/Haploturbels with ice-cemented permafrost at < 70cm are most common in each of these geomorphic regions. Amongst the Haplo Great Groups are patches of Salic and Typic Anhyorthels with ice-cemented permafrost at > 70 cm. They are developed in situ in strongly weathered drift with very low surface boulder frequency and occur on the upper erosion surface of the Labyrinth and on the Dais. Typic Anhyorthels also occur at lower elevation on sinuous and patchy Wright Upper III drift within the forks. Salic Aquorthels exist only in the South Fork marginal to Don Juan Pond, whereas Salic Haplorthels occur in low areas of both South and North forks where any water table is> 50 cm. Most soils within the study area have an alkaline pH dominated by Na+ and Cl- ions. The low salt accumulation within Haplorthels/Haploturbels may be due to limited depth of soil development and possibly leaching.

Supraglacial lakes form in Antarctic blue ice regions from penetration of solar radiation into the ice in summer. Three lakes were mapped for their structure in summers 2004–05 and 2010–11 in western Dronning Maud Land, and one was also examined for the radiation budget. The lake body consisted of two layers, each ∼1 m thick: an upper layer with a thin ice layer on top and main body of liquid water, and a lower layer containing slush and hard ice sub-layers. A sediment-rich slush pocket was found at the bottom. Hydraulic conductivity of the lake body was 0.25–30 cm s-1 depending on the stage of evolution, with 6.3 cm s-1 for closely packed slush. Albedo of the lake was 0.4–0.6 and light attenuation coefficient was 0.5–0.7 m-1. The formation and the depth scale of the lakes are determined by the light attenuation distance and thermal diffusion coefficient, limiting the growth to less than about 1.5 m in one summer. The potential winter growth is more and thus the lakes freeze up in winter in the present climatic conditions.

Four distinctive morphological types can be found among living Globocassidulina in surface sediments of Admiralty Bay (King George Island, South Shetland Islands). The molecular analysis of the SSU and ITS rDNA indicates that they are monospecific and belong to Globocassidulina biora, except for minute forms from deeper than 200 m water depth which probably represent G. subglobosa. The morphological types of G. biora that show doubled or branched apertures, varied test size and shape as well as colour of cytoplasm, represent populations at different stages of ontogenetic development. However, the variability among large G. biora from the same locations is difficult to comprehend. It seems probable that G. biora is the only recent, large, shallow water Globocassidulina represented throughout the Antarctica, while G. crassa is typical for the Magellan region.

The distribution of the icefish Champsocephalus gunnari on the Kerguelen Plateau is confined to the inner shelves of Heard and Kerguelen islands and outlying banks where the water depth is less than 350 m. For fisheries management purposes, it is necessary to know whether fish from the various shelves and banks belong to one single or several separate populations. Analysis of the mitochondrial DNA of fish from various localities using restriction endonclease enzymes revealed no significant genetic heterogeneity between any of the localities. This does not preclude the existence of isolated stocks at the present time but indicates that the populations have been separated too recently for genetic isolation to be manifested, or that low-level interchange of fish between the populations may be maintaining genetic homogeneity.

Late Cretaceous sedimentary rocks assigned to the Santa Marta (Herbert Sound Member) and López de Bertodano (Cape Lamb and Sandwich Bluff members) formations of the Marambio Group, crop out on Cape Lamb, Vega Island. Although previous studies have recognized that these sedimentary rocks were derived from the northern Antarctic Peninsula region, the work presented here allows the provenance and palaeogeographical evolution of the region to be described in detail. On the basis of both sandstone petrography and clay mineralogy, the Herbert Sound and Cape Lamb members reflect sediment input from a low relief source area, with sand grade sediment sourced from low grade metasediments, and clay grade sediment ultimately derived from the weathering of an andesitic source area. In contrast, the Sandwich Bluff Member reflects a switch to a predominantly andesitic volcaniclastic source. However, this sediment was largely derived from older volcanic suites due to renewed source area uplift, with only a minor component from coeval volcanism. Regional uplift of both the arc terrane and the western margin of the James Ross Basin was likely during the Maastrichtian.

Müller Ice Shelf (67°15′S, 66°52′W) is situated at the southern end of Lallemand Fjord. It is a small ice shelf (∼80 km2) fed by Brückner and Antevs glaciers, which both flow northward off the central peaks of Arrowsmith Peninsula; the ice shelf contains an ice rise (Humphreys Ice Rise). Data sources have indicated that not only has the ice front retreated since 1947 but also that there have been two advances. This paper describes how these changes were recorded using simple photogrammetric techniques.

On the basis of observations of Weddell seals (Leptonychotes weddellii Lesson) made in the course of studying shallow-water benthic communities in McMurdo Sound, Antarctica, we suggest that caching and/or defence of uneaten food may be a strategy practiced by this animal. Such a phenomenon is uncommon but taxonomically widespread among vertebrates. Depending on circumstances, it is termed hoarding, caching, or storage and may be short- or long-term, include defence of the resource, or have other variable expressions, with the common threads being deferred consumption and deterrence of consumption by others (Vanderwall 1990). Many vertebrate taxa exhibit hoarding behaviour, including rodents (e.g. Sciuridae), carnivores (e.g. Canidae, Felinidae) and birds (e.g. Corvidae, Picidae). No form of food caching, to our knowledge, has ever been reported in a wild pinniped.

Palynological analyses of the Marambio Group sediments of Humps Island (Santa Marta and López de Bertodano formations) indicates that there is minor displacement across a prominent NW–SE trending normal fault which passes beneath the southern bluff. No major compositional differences were perceived between the palynomorph assemblages either side of the fault. A late Campanian age is suggested for both sequences, based on comparison with Australasian dinoflagellate cyst zonations. A new species of the dinoflagellate cyst Bourkidinium has been recorded from strata on either side of the fault. A significant number of recycled Permian and Early Cretaceous palynomorphs were recorded. Most are miospores and exhibit significant variation in preservational states, implying derivation from several sources. More thermally mature Permian gymnosperm pollen is most likely derived from the nearby Trinity Peninsula Group, exposed on the Antarctic Peninsula. The source of the relatively well preserved Permian pollen is problematic.

Summer iron (Fe) fertilization in the Ross Sea has previously been observed in association with diatom productivity, lithogenic particles and excess Fe in the water column. This productivity event occurred during an early breakout of sea ice via katabatic winds, suggesting that aeolian dust could be an important source of lithogenic Fe required for diatom growth in the Ross Sea. Here we investigate the provenance of size-selected dust deposited on sea ice in McMurdo Sound, south-western (SW) Ross Sea. The isotopic signature of McMurdo Sound dust (0.70533<87Sr/86Sr<0.70915 and -1.1<εNd(0)<3.45) confirms that dust is locally sourced from the McMurdo Sound debris bands and comprises a two-component mixture of McMurdo Volcanic Group and southern Victoria Land lithologies. In addition, the provenance of lithogenic sediment trapped in the water column was investigated, and the isotopic signature (εNd(0)=3.9, 87Sr/86Sr=0.70434) is differentiated from long-range transported dust originating from South America and Australia. Elevated lithogenic accumulation rates in deeper sediment traps in the Ross Sea suggest that sinking particles in the water column cannot simply result from dust input at the surface. This discrepancy can be best explained by significant upwelling and remobilization of lithogenic Fe from the sea floor.

We examined mitochondrial DNA (COI) variability and distribution of Stereotydeus spp. in Victoria Land and the Transantarctic Mountains, and constructed Neighbour Joining (NJ) and Maximum Likelihood (ML) phylogenetic trees using all publicly available COI sequences for the three Stereotydeus species present (S. belli, S. mollis and S. shoupi). We also included new COI sequences from Miers, Marshall and Garwood valleys in southern Victoria Land (78°S), as well as from the Darwin (79°S) and Beardmore Glacier (83°S) regions. Both NJ and ML methods produced trees which were similar in topology differing only in the placement of the single available S. belli sequence from Cape Hallett (72°S) and a S. mollis haplotype from Miers Valley. Pairwise sequence divergences among species ranged from 9.5–18.1%. NJ and ML grouped S. shoupi from the Beardmore Glacier region as sister to those from the Darwin with pairwise divergences of 8%. These individuals formed a monophyletic clade with high bootstrap support basal to S. mollis and S. belli. Based on these new data, we suggest that the distributional range of S. shoupi extends northward to Darwin Glacier and that a barrier to dispersal for Stereotydeus, and possibly other arthropods, exists immediately to the north of this area.

Studies were continued to investigate the ability of secondary metabolites sequestered in Antarctic sponges to cause feeding deterrent responses (tube foot retractions) in a common predator of Aritarctic sponges, the sea star Perknaster fuscus. Lipophilic (dichloromethane/methanol) and hydrophilic (methanol/water) extracts of 15 new species of Antarctic marine sponges were tested for their ability to induce sustained tubefoot retraction. One additional species, Cinchyra antarctica, was re-tested from a previous study because we discovered a colour morph that was of comparative interest. Employing established protocols, sponge extracts were imbedded in silicone and presented to an extended tube-foot on the tip of a glass rod. Extracts of ten of the 15 new species of sponges (67%) caused significantly longer tube-foot retractions than controls. Among all sponges tested, significant tube-foot retraction activity was primarily associated with dichloromethane/methanol extracts (eleven sponge species or colour morphs), while significant tube-foot retraction activity was less common in response to methanol/water extracts (three sponges species or colour morphs). Both lipophilic and hydrophilic extracts from the sponges C. antarctica (yellow morph) and Scolymastia joubini elicited significant tube-foot retraction activity, suggesting that more than one compound from these speciesmight elicit tube-foot retractions in P. fuscus. Overall these findings lend considerable support to the hypothesis that there has been significant evolutionary selection for chemical defences among Antarctic marine sponges in McMurdo Sound, in contrast to earlier biogeographic selection models that predicted low levels of chemical defences in polar marine invertebrates.