Abstract: During the last decades, eco-physiological studies have usually relied on the collection of blood from wild organisms in order to obtain relevant physiological measures. However, accurate estimates of the impact of capture and blood collection on performances of Polar seabird species have rarely been conducted. We investigated for the first time the effects of a blood sampling process on subsequent foraging behaviour, reproductive performance and return rate of black-browed albatrosses ( Thalassarche melanophris ) at Kerguelen Islands. We did not find any evidence that the blood sampling process as conducted in our study had detrimental effects on the breeding or foraging strategies or performance of black-browed albatrosses. Because blood collection can be performed in several different ways, we recommend that eco-physiologists conduct pilot studies to test whether their blood sampling process affects the performances of their study species.

Abstract: Ptilocrinus amezianeae n. sp. is a new species of stalked crinoid attributed to the family Hyocrinidae. Forty-five specimens were collected from seamounts north of the Ross Sea, and one specimen from the Kerguelen Plateau at depths ranging from 450 to 1,680 m. The collection from Admiralty and Scott seamounts constitutes the first example of a hyocrinid population known both from in situ photographs and from numerous collected specimens ranging from small juvenile to large adult. Variation in theca and stalk articulation characters throughout ontogeny is congruent with the molecular data and indicates that all the specimens examined belong to a single species. Tegmen and pinnule architecture, brachial arrangement, and stalk articular facets indicate that Ptilocrinus amezianeae n. sp. has close affinities with P. clarki and P. pinnatus from the northeastern Pacific and displays the most derived characters among these three species. Two cases of true arm division into two unequal branches suggest that Ptilocrinus and Calamocrinus are closely related. The picture and video transects on Admiralty seamount show a patchy distribution of living specimens with patches of mean density ca. 2.6 individuals m-2. In situ photographs also document predation by a sea urchin and a sea star on tegmen and proximal arms. The COI gene sequences analyzed in 25 specimens from Admiralty and Scott seamounts display low pairwise distances, low nucleotidic diversity, and intermediate haplotype diversity. These results, together with disarticulated ossicles and attachment disks observed on in situ photographs, indicate that the population investigated here is in decline.

Abstract: The Southern Ocean benthic communities are characterized by their levels of endemism and their diversity of invertebrate brooding species. Overall, biological processes acting within these species remain poorly understood despite their importance to understand impacts of ongoing global change. We take part in filling this gap by studying the genetic structure over different spatial scales (from centimeters to tens of kilometers) in Abatus cordatus , an endemic and brooding sea urchin from the Kerguelen Islands. We developed three microsatellites and two exon-primed intron crossing markers and conducted a two-scale sampling scheme (from individuals to patches) within two dense localities of Abatus cordatus . Between patches, all pairwise comparisons, covering distances from few meters (between patches within locality) to 25 km (between localities), revealed significant genetic differentiation, a higher proportion of the molecular variance being explained by the comparisons between localities than within localities, in agreement with an isolation by distance model. Within patches, we found no significant correlation between individual pairwise spatial and genetic distances, except for the most polymorphic locus in the patch where the largest range of geographical distances had been analyzed. This study provides an estimation of the dispersal capacities of Abatus cordatus and highlights its low recolonization ability. Similar low recolonization capacities are thus expected in other Antarctic and Subantarctic brooding invertebrate species and suggest a high vulnerability of these species facing global change.