Abstract: The poorly known winter foraging ecology of the king penguin, a major Southern Ocean consumer, was investigated at the subantarctic Crozet Islands where the largest global population breeds. Blood δ13C and δ15N values were used as proxies of the birds’ foraging habitat and diet, respectively, and circulating prolactin levels helped in determining the birds’ reproductive status. Plasma prolactin concentrations showed that king penguin adults of unknown breeding status (n = 52) that were present at the colony in winter were in fact breeders and failed breeders, but were not non -breeders. Circulating prolactin was neither related to δ13C nor δ15N values, thus suggesting that both breeders and failed breeders used the same foraging habitats and fed on the same prey. Plasma and blood cell isotopic values depicted four new relevant biological features on the feeding strategies of king penguins during the critical winter period: (1) 42% of the birds foraged in the distant Antarctic Zone, but 58% fed primarily in subantarctic waters (δ13C), (2) they preyed upon myctophids in both zones (δ15N), (3) individuals were consistent in their foraging strategies over the winter months (δ13C and δ15N), and (4) a higher proportion of females (77%–80%) than males (27%–31%) favored feeding in distant Antarctic waters (δ13C). This study highlights trophic connectivity between subantarctic and Antarctic ecosystems and hence the key role of energy export from Antarctic waters to sustain breeding populations of subantarctic predators, including during the Austral winter.

Abstract: This review presents an innovative approach to investigate the teuthofauna from the Southern Ocean by combining two complementary data sets, the literature on cephalopod taxonomy and biogeography, together with predator dietary investigations. Sixty squids were recorded south of the Subtropical Front, including one circumpolar Antarctic (Psychroteuthis glacialis Thiele, 1920), 13 circumpolar Southern Ocean, 20 circumpolar subantarctic, eight regional subantarctic, and 12 occasional subantarctic species. A critical evaluation removed five species from the list, and one species has an unknown taxonomic status. The 42 Southern Ocean squids belong to three large taxonomic units, bathyteuthoids (n = 1 species), myopsids (n = 1), and oegopsids (n = 40). A high level of endemism (21 species, 50%, all oegopsids) characterizes the Southern Ocean teuthofauna. Seventeen families of oegopsids are represented, with three dominating families, onychoteuthids (seven species, five endemics), ommastrephids (six species, three endemics), and cranchiids (five species, three endemics). Recent improvements in beak identification and taxonomy allowed making new correspondence between beak and species names, such as Galiteuthis suhmi (Hoyle 1886), Liguriella podophtalma Issel, 1908, and the recently described Taonius notalia Evans, in prep. Gonatus phoebetriae beaks were synonymized with those of Gonatopsis octopedatus Sasaki, 1920, thus increasing significantly the number of records and detailing the circumpolar distribution of this rarely caught Southern Ocean squid. The review extends considerably the number of species, including endemics, recorded from the Southern Ocean, but it also highlights that the corresponding species to two well-described beaks (Moroteuthopsis sp. B and Psychroteuthis sp. B) are still unknown.

Abstract: The Antarctic Conoidean fauna is critically reviewed based on published data and specimens in the collections of the USNM, IORAS and MNHN. Forty-two species and subspecies of the superfamily Conoidea are recorded as occurring within the Antarctic Convergence (excluding the fauna of the Kerguelen Islands) and are attributed to 14 genera and seven families. These include the new taxa: Antarctospira n. gen. (type species—Leucosyrinx badenpowelli Dell, 1990); Drilliola antarctica n. sp.; Pleurotomella (Pleutoromella) tippetti n. sp.; Pleurotomella (Anomalotomella) petiti n. sp.; Xanthodaphne pastorinoi n. sp. Aforia watsoni is introduced as a new name for Pleurotoma (Surcula) lepta Watson, 1881, non Pleurotoma lepta Edwards, 1861. A lectotype is designated for Conorbella antarctica (Strebel, 1908). New combinations are also proposed. Antarctospira badenpowelli (Dell, 1990), n. comb. (previously assigned to Leucosyrinx); Antarctospira principalis (Thiele, 1912), n. comb. (previously assigned to Typhlomangelia); Antarctospira mawsoni (Powell, 1958), n. comb. (previously assigned to Leucosyrinx); Typhlodaphne paratenoceras (Powell, 1951), n. comb. (previously assigned to Leucosyrinx); Belalora weirichi (Engl, 2008), n. comb. (previously assigned to Oenopota); Pleurotomella (Anomalotomella) innocentia (Dell, 1990), n. comb. (previously assigned to Typhlodaphne); Pleurotomella (Anomalotomella) nipri (Numanami, 1996), n. comb. (previously assigned to Typhlodaphne); Xanthodaphne raineri (Engl, 2008), n. comb. (previously assigned to Pleurotomella); Aforia hedleyi (Dell, 1990), n. comb. (previously assigned to Pontiothauma). The majority of Antarctic conoidean taxa have hypodermic marginal teeth. Although there is a similar relative abundance of conoideans in Antarctic waters to that seen in other well-studied faunas, the low number of conoideans is indicative of the general impoverishment of the gastropod fauna in the region. Fourteen percent (2 of 14) of conoidean genera that occur within the Antarctic Convergence are endemic to Antarctic waters, as are 82% (34 of 42) of the species. Most taxa have very broad bathymetric ranges, some extending from bathyal to hadal depths. The greatest species diversity was at bathyal depths.