Albino Weddell seal at Cape Shirreff,Livingston Island,Antarctica

To our knowledge, this paper is the first record/report of a juvenile light-coloured Weddell seal (Leptonychotes weddellii) at Cape Shirreff, Livingston Island in January 1998, determining that it was an albino individual. Based on available literature, three cases of albino seals have been reported exclusively for Harbour seal pups, and no albino has been reported for Antarctic pagophilic true seals. Therefore, this is the first confirmed case of albinism in Antarctic pagophilic true seals species, indicating that this phenomenon is indeed of a rare occurrence.

Feeding ecology of Antarctic fur seals at Cape Shirreff,South Shetlands,Antarctica

This study examined the diet of Antarctic fur seals, Arctocephalus gazella, from an active breeding colony at Cape Shirreff (62°28S, 60°48W), Livingston Island, South Shetland Archipelago, Antarctica. It analysed faecal samples from five consecutive years (1997–2001) and length distribution of krill taken by trawl nets in the vicinity of Livingston Island. Antarctic krill, Euphausia superba, was the most frequent prey item, followed by several myctophid species (Gymnoscopelus nicholsi, Electrona antarctica and Electrona carlsbergi), squid and penguin remains. From 1998 to 2001, a modal progression in krill size was evident, suggesting that A. gazella was depending on a strong krill cohort, at least over the study period. Analysis of size distribution and size selectivity of krill preyed upon by fur seals suggests a preference for larger krill (>34 mm), despite the broader size range of preys items available.     

Vagrant elephant seal predation on Cape fur seal pups, Plettenberg Bay, South Africa

Vagrant southern elephant seals (Mirounga leonina) are occasionally sighted along the coast of South Africa and are known to feed primarily on fish and squid. Phocid seals are not known to predate on mammals making the events described here exceptional. This note describes the successful and failed attempts of a vagrant male southern elephant seal (M. leonina) to consume Cape fur seal (Arctocephalus pusillus pusillus) pups in Plettenberg Bay, South Africa. Observations were made by crew and passengers aboard a commercial whale-watching vessel during November 2012. This is the first account of elephant seals eating anything other than fish, squid and penguins and suggests considerable plasticity in prey choice dictated by environmental conditions.     

Rare piebald and partially leucistic Antarctic fur seals, <Emphasis Type="Italic">Arctocephalus gazella</Emphasis>, at Cape Shirreff,Livingston Island,Antarctica

We document five cases of unusual colouration in Antarctic fur seals, Arctocephalus gazella, at Cape Shirreff, Livingston Island, from 1991–1992 to 2005–2006 austral summer seasons. This is the first time that these colour patterns have been reported for this species. These included four rare light coloured animals and one piebald individual. The incidence of this atypical colouring was low and the lack of resightings in previous and subsequent seasons suggests that these morphs are not common in Antarctic fur seals. Although the causes of these atypical light colour patterns are uncertain the subject is interesting for study and more observations on these atypical colourations are required for a proper assessment of the ecological and physiological implications of this condition in otariids can be conducted in the future.     

Trend changes in sympatric Subantarctic and Antarctic fur seal pup populations at Marion Island,Southern Ocean

Recent pup population estimates of sympatric Subantarctic (Arctocephalus tropicalis) and Antarctic fur seals (A. gazella) at Marion Island are presented. Published pup population estimates of A. tropicalis (1995 and 2004) with an unpublished total island count in 2013, and annual counts on subsets of rookeries (2007–2015) were analyzed using a hierarchical Bayesian model. The pup population declined by 46% (95% credible interval CI: 43%–48%) between 2004 (mean = 15,260, CI: 14,447–16,169 pups) and 2013 (mean = 8,312, CI: 7,983–8,697), mirrored by a 58%–60% decline at rookeries counted annually (2007–2015). Population decline was highest at high‐density west and north coast rookeries, despite negligible change in female attendance patterns, pup mortality or median pupping date over the previous 25 yr. A better understanding of foraging behavior and its effects on reproductive success and survival in this A. tropicalis population is needed before we can attribute population decline to any external factors. In contrast, total island counts of A. gazella pups in 2007, 2010, and 2013, suggest that this population is still increasing although the annual intrinsic rate of population growth decreased from 17.0% (1995–2004, 744 pups) to 4.0% (2010–2013, 1,553 pups). The slowed growth of A. gazella is likely the result of saturation at the main rookery.     

Vagrant Antarctic fur seals at Gough Island in 2009

The Antarctic fur seal Arctocephalus gazella at Gough Island (40°20′S, 09°54′W) in the South Atlantic Ocean, first seen in October/November 2005, was recorded again in September–October 2009. Up to three different individual Antarctic fur seals were sighted on a single day, on a particular beach. A total of seven different individuals were recorded over a 3-week period, well before the onset of the breeding (pupping) season of the resident population of Subantarctic fur seals A. tropicalis. Positively identified individuals were all male, mostly subadult and lean. Only a fraction (~20%) of the available beaches was searched, and it is unknown if the Antarctic fur seals were still present at Gough Island during the austral summer breeding season of southern fur seals.     

Yeast strains from Livingston Island, Antarctica

Five yeast strains were isolated from soil and moss samples from the Livingston Island (Antarctica) and identified according to morphological, cultural and physiological characteristics. All strains had an optimum growth temperature of 15°C; none grew above 25°C. They assimilatedD-glucose.D-galactose, sucrose, cellobiose, trehalose, 2-keto-d-gluconate,D-xylose,d-ribose and melezitose. Four of them were nonfermentative, only one, which formed pseudomycelium fermented glucose, galactose, trehalose. Two strains were identified as pinkred yeasts belonging to genusRhodotorula—R. minuta andR. mucilaginosa; two were related to the genusCryptococcus—C. albidus andC. laurentii, one wasCandida oleophila.     

Fetus presentation and time taken for parturition in Antarctic fur seal, <Emphasis Type="Italic">Arctocephalus gazella</Emphasis>, at Cape Shirreff,Antarctica

We document the influence of fetus orientation in the time invested in the birthing process of Antarctic fur seals at Cape Shirreff, Antarctica. Our results show that breeching was significantly higher than cephalic orientation on the order of 1.5:1. The average duration of the birthing process was 37.26 min, and the average duration considering the fetus orientation was 27.22 and 49.39 min for the cephalic and breech, respectively. The average time was significantly different only in the phase from the appearance of the amniotic-allantoids sac to the complete expulsion of the pup. Possible explanations for this difference are: the friction between the opposite hair direction with the uterus-vaginal wall after the rupture of amnio-allantoid sac during the transit of the fetus in breech position, and/or the fact one or both front flippers would increase the scapular diameter and make the final step of fetus delivery more difficult.     

Prevalence of allosuckling behaviour in Subantarctic fur seal pups

Non-offspring maternal care should be rare due to the high costs of raising offspring, particularly lactation, but nonetheless occurs in a variety of taxa. Misguided parental care, associated with recognition errors and/or inattentiveness by lactating females, has been hypothesized as an explanation for allolactation in mammals. In an extension of this hypothesis, we suggest that milk-stealing is parasitism instigated by non-filial offspring, and that maternal behaviour is of secondary interest in an evolutionary context if she is unaware of the interaction. We provide evidence for frequent milk-stealing attempts by Subantarctic fur seal (Arctocephalus tropicalis) pups, including an example of sustained non-maternal care (> three months) for one pup during the confirmed absence of his mother, leading to a weaning mass equal to the population mean. We also present only the second account of fostering/twins in the species at this locality. We suggest that rather than the hitherto suggested rare and anomalous behaviour, milk-stealing behaviour (while not always successful) is common.     

Antarctic fur seal predation on cephalopods at Marion Island

We report two observations of adult male Antarctic fur seals, Arctocephalus gazella, preying on large octopods at subAntarctic Marion Island during July and August 2008. If Antarctic fur seals take cephalopods opportunistically, as previously suggested, our observations may be a rare event representing such opportunistic predation.     

Lipid composition of some yeast strains from Livingston Island, Antarctica

Yeast strainsCryptococcus albidus, Cryptococcus laurentii, Rhodotorula minuta were isolated from a moss sample,Candida oleophila andRhodotorula mucilaginosa were isolated from a soil sample taken from Livingston Island. Antarctica. Fatty acid, phospholipid, sterol and tocopherol composition was determined in separated lipid fraction after fermentation in a medium containing glucose, peptone and yeast extract. Unsaturated fatty acids, mainly oleic (51–65%) and linoleic (9.5–16.8%), predominated in triacylglycerols. Sterols represent ca. 120–930 mg per kg dry biomass. The content of major phospholipids (phosphatidylcholine, phosphatidylinositol and phosphatidylethanolamine) was ca. 100–800 mg/kg. The amount of tocopherols (mainly γ- and δ-tocopherol) was 2.1–6.3 mg/kg.     

Precipitation nitrogen at maritime Signy Island and continental Cape Bird,Antarctica

Summary The mineral nitrogen (NH₄-N + NO₃-N) in precipitation occurring at continental and maritime Antarctic sites has been determined. Precipitation at sites remote from animal activity contained much less mineral N than that occurring at sites influenced by such activity. Estimates for nitrogen input at two contrasting fellfield sites, one at continental Cape Bird (dry site), the other at maritime Signy Island (wet site) are presented. At both sites precipitation N represented the major N input to fellfield biota than did wind blown particulate matter containing organic nitrogen or ammonia volatilized from adjacent guano soils and becoming absorbed by moist artificial soils traps.     

On the distribution of terrestrial invertebrates at Cape Bird, Ross Island, Antarctica

Terrestrial invertebrate distribution was surveyed over 12 km² of the ice-free area at Cape Bird, Ross Island, Antarctica. Gomphiocephalus hodgsoni (Collembola: Hypogastruridae), Stereotydeus mollis and Nanorchestes antarcticus (Acari: Prostigmata), Panagrolaimus davidi, Plectus sp. and Scottnema lindsayae (Nematoda), Tardigrada, Rotifera and Protozoa were all recorded. Invertebrates were found at 47 of 103 locations sampled. Logistic regression analysis suggested that the presence of mites and Collembola was strongly related to chlorophyll-a content of soil; but only Stereotydeus mollis and N. antarcticus were related to the presence of macroscopic vegetation, suggesting that current methods of assessing areas for protection may not adequately allow for invertebrate communities. Invertebrate communities were not dependent on ornithogenic carbon input. A better understanding of dispersal mechanisms is necessary to understand distributions of invertebrates in ice-free areas, particularly in light of potential habitat changes as a result of climate change.     

Breeding cycle of the Cape petrel Daption capense at Nelson Island, Antarctica

Timing and duration of the breeding cycle of the Cape petrel Daption capense were studied during two breeding seasons (1990/1991 and 1991/1992) at Nelson Island, South Shetland Islands, Antarctica. In 1991/1992 the copulatory period extended over 53 days, with median date and a peak about 28 and 19 days respectively, before the median date of laying. Laying began 85 days after arrival, with mean (= median) date on 2 December (SD = 2.5 days). The distributions of laying, hatching and fledging dates showed a similar degree of synchrony and did not differ between years. Incubation and chick period were equally long (46 days), the former being less variable (coefficient of variation = 2.8% and 4.6%, respectively). Mean completed nesting cycle (92 days) was about 2 days shorter at Nelson Island than elsewhere and tended to shorten as the breeding season progressed. Its mean length represented 86% of the whole nesting period (107 days), which in turn represented 56% of the period of continuous colony attendance. Timing and duration of nesting stages did not differ between colonies or sets of nests subjected to various levels of disturbance. Received: 8 July 1996 / Accepted: 11 November 1996     

Secondary metabolites from a Streptomyces strain isolated from Livingston Island, Antarctica

The producing strain Streptomyces sp. 1010 was isolated from a shallow sea sediment from the region of Livingston Island, Antarctica. From the culture broth of this strain naturally active secondary metabolites were isolated identical to phthalic acid diethyl ester (C12H14O4, MW. 222); 1, 3-bis (3-phenoxyphenoxy)benzene (C30H22O4, MW.446); hexanedioic acid dioctyl ester (C22H42O4, MW.370) and the new substance 2-amino- 9, 13 -dimethyl heptadecanoic acid (C19H39NO2, MW.313). These compounds represent diverse classes of chemical structures and provide evidence for the untapped biosynthetic potential of marine bacteria from Antarctica.     

The diet of the subantarctic fur seal Arctocephalus tropicalis at Marion Island

Scats of subantarctic fur seals Arctocephalus tropicalis at Marion Island were collected from 1996 to 2,000, to examine temporal variability in the diet, factors affecting the variability and how the diet differed from that of the Antarctic fur seal A. gazella in the same period. For A. tropicalis, 19 prey species, of which 18 were fish and one a cephalopod, were identified in 213 scats. Fish were the main prey, occurring in 98.1 % of scats, whereas the cephalopod was present in only 1.4 % of scats. Amongst fish species, Myctophidae were most abundant, with Gymnoscopelus piabilis, G. fraseri and Electrona carlsbergi being the commonest prey items. Other fish families present in the diet in small numbers were Channichthyidae, Paralepididae, Nototheniidae, Microstomatidae and Notosudidae. Fish eaten ranged in size from Protomyctophum bolini and Krefftichthys anderssoni of standard length (SL) 25 mm to a single Dissostichus eleginoides of SL 249 mm. Differences in the diet existed between summer and winter. However, prey type accounted for most variability in the diet. In previous studies based on scats, a dominance of fish in the diet of A. tropicalis was also found at Possession Island (Iles Crozet), Amsterdam Island and Macquarie Island, but the dominant prey species differed between the various localities, also suggesting that prey availability is a major determinant of diet. At Marion Island, from 1996 to 2000 the diet of A. gazella comprised similar prey to that of A. tropicalis, but the proportional contribution of prey types differed in instances.