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The article discusses fieldwork conducted on Marion Island, South Africa's Prince Edward Islands, during which breeding behavior in three colonies of Wandering albatross located in Macaroni Bay, Sealer's Beach, and Goney Plain from 2006 to 2009 was observed. Topics discussed include the presence of male and female Wandering albatross in the breeding colony during the pre-laying season, laying dates and periods of laying, and hatching dates and incubation periods.

Marine ecosystems face a variety of threats induced by environmental changes and anthropogenic activities. Seabirds are predators often used as indicator species to monitor the status and health of their communities and the environment. Here, we present the results from a 35-year monitoring time series of Brown Skuas ( Catharacta antarctica lonnbergi) and South Polar Skuas ( C. maccormicki) breeding sympatrically in the Maritime Antarctic on Fildes Peninsula and Potter Peninsula, King George Island. Our results reveal high annual variability in the number and proportions of breeding pairs across the entire study period. Apart from that, the breeding pair numbers of Brown Skuas were relatively stable. By contrast, the breeding pair number of mixed species and South Polar Skua pairs increased substantially until 2003/2004 and 2010/2011, respectively. Both pair types experienced a decline in the breeding pair numbers within recent years. Despite the strong fluctuations in the number of breeding pairs, the sum of occupied territories has been stable during the last 9 years. The breeding success of all pair types declined significantly, and within recent years, both South Polar Skuas and mixed species pairs completely failed to produce offspring. The ultimate causes driving the breeding success decline remain unclear. The overall increase in the number of skuas might have raised density-dependent factors and resulted in a higher predation rate between conspecifics. The more recent total breeding failures, however, indicate a drastic shortage in local food availability. [ABSTRACT FROM AUTHOR]

Studies on Antarctic intertidal fauna are comparatively scarce compared to those from the sublittoral and the deep sea. In order to contribute to filling this gap in knowledge, during the 2006 BENTART Spanish Antarctic Expedition, we conducted a quantitative and qualitative study on the fauna inhabiting the intertidal rocky platform of Fildes (=Maxwell) Bay, King George Island (South Shetlands Archipelago). This platform is dominated in its middle and lower area by the brown algae Adenocystis utricularis, which covers ca. 100 % of the rocky surface. Three quantitative samples of 20 × 20 cm were taken in the community of A. utricularis, and one additional sample of 20 × 20 cm in the tide pools community dominated by the gigartinacean rhodophyceae Iridaea cordata. In addition, qualitative samples of invertebrates that live under the boulders were also taken. Quantitative samples yielded a total of 9950 individuals belonging to 41 species. Mollusks were the most abundant group with a total of 9522 specimens belonging to 11 species, being the gastropod Eatoniella kerguelenensis regularis the most abundant with 6763 specimens. Crustaceans were represented by 295 specimens and 7 species and annelid polychaetes with 133 specimens and 20 taxa. The Shannon diversity indexes calculated for the quantitative samples of A. utricularis ranged between 0.803 and 1.030 with values of 1.577 for the I. cordata community. Our study confirms that the intertidal area of Fildes Bay hosts a surprisingly rich community in terms of abundance and biodiversity. [ABSTRACT FROM AUTHOR]

In spite of general knowledge that guano deposited near seabird colonies enhances fertility of poor polar soils, improves primary production and influences the tundra plant community, there are very few quantitative studies concerning plant responses to ornithogenic fertilization on the population level. We studied density, size variability and proportions of generative to vegetative individuals of polar scurvygrass Cochlearia groenlandica along a seabird influence gradient in south-west Spitsbergen. We found the seabird colony effect to being a predominant factor determining local ascurvygrass population structure. Plant density was increasing starting from the foot of the cliff (820 ind/m) and reaching the highest value (7500 ind/m) about 30 m from the colony. This density peak was a result of the flowering plants occurring in the area above in the highest number which produced plenty of seeds germinating several metres below. The density of flowering plants was significantly correlated with the physical and chemical features of the soil but concerned only small individuals (1-4 cm), whose numbers were negatively correlated with the level of available nutrients, and large-sized (13-20 cm) plants, which were correlated positively. The only significant factor influencing flowering plant density along the bird colony gradient was the content of organic matter in the soil. In the control transect, total plant density was three orders of magnitude lower. No or weak correlations were found between plant density and soil characteristics along that transect. Our study supports the hypothesis that seabirds have fundamental importance not only for vegetation abundance in the nutrient-poor Arctic environment but also to determine plant population structure in the vicinity of large breeding colonies. [ABSTRACT FROM AUTHOR]

Biological invasions and climate change are two of the largest threats to biodiversity, and this is especially true for island ecosystems that have largely evolved in isolation. The house mouse is considered to have been introduced to sub-Antarctic Marion Island by sealers in the early 1800s. It is currently widespread across the island and has a large impact on the indigenous biota. To date, little information is available on genetic aspects of biological invasions in the sub-Antarctic. Ten specimens of the house mouse were collected from two geographically separated localities on Marion Island. Sequences of the mitochondrial DNA control region revealed only two haplotypes, separated by a single site change. More importantly, these haplotypes are shared between the eastern and western side of Marion Island. By comparing our sequences to data available on GenBank, we provide evidence that house mice on Marion Island is Mus musculus domesticus (Rutty 1772), and most closely related to haplotypes characterizing this species from Denmark, Sweden, Finland, and northern Germany. [ABSTRACT FROM AUTHOR]

Bouvet Island is, uniquely, thousands of km from the next nearest land, even other islands. Its Southern Ocean location, isolation and the exposure of its surrounding cliffs have resulted in only rare visits by ship and its coastal marine fauna is little known. For animal taxa with non-pelagic larvae, such as cheilostome bryozoans, the shelf environment of Bouvet is a rare example of isolated oceanic communities. Agassiz trawl samples of the 2003 ANT XXI-2 cruise of the PFS Polarstern collected a total of 18 species of cheilostomes at four sites around Bouvet Island. Of these only four had been reported before amongst the 20 species of cheilostome previously known from this locality. Furthermore eight of the genera are reported for the first time from Bouvet Island. The assemblages were dominated by Austroflustra vulgaris, and in one case Nematoflustra flagellata. The bryozoan fauna seems to be depauperate and bears only low (32% at species and 46% at genus level) similarity to any location within 3,000 km. Its species composition is typically Southern Ocean, with most affinity to the Scotia Arc and Weddell Sea whereas at generic level it is most similar to the Subantarctic Prince Edward Archipelago. [ABSTRACT FROM AUTHOR]

Bouvet Island is one of the most isolated islands in the Southern Ocean and its marine benthic fauna has rarely been investigated and so is poorly known. This study adds 30 molluscan species to the previous faunal record of 16 species. During the expedition ANT XXI-2 of PFS Polarstern 25 species of shelled gastropods, 12 species of bivalves, 3 species of polyplacophorans and 1 species of solenogaster (Aplacophora) were collected at four sites around Bouvet Island in depths between 120 m and 550 m. High percentages of the species representing the shelled molluscan fauna of Bouvet Island are known from sub and high (continental) Antarctica. [ABSTRACT FROM AUTHOR]

Mega-epibenthic diversity was analysed using a seabed photography at four stations off Bouvet Island and one station at the Spiess Seamount in the South Atlantic. Surprisingly, the intermediate-scale diversity within the area of investigation was not lower compared to that on the Patagonian shelf and only moderately lower than that on the Antarctic continental shelf. This result is incompatible with Mac Arthur and Wilson’s Island Biogeography Theory describing species richness as a function of immigration of new species into an area and its extension. The relatively high species number and the very small extension of the Bouvet shelf compared to the much larger continental shelves of the other two areas can be explained by long-range dispersal of marine benthic animals in the Antarctic Circumpolar Current and high habitat heterogeneity. The observed uncoupling of intermediate-scale from large-scale background species diversity on the Antarctic shelf raises the question whether in these benthic systems an upper capacity limit for diversity exists. [ABSTRACT FROM AUTHOR]