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The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research project led jointly by the Expert Groups on Birds and Marine Mammals and Antarctic Biodiversity Informatics, and endorsed by the Commission for the Conservation of Antarctic Marine Living Resources. RAATD consolidated tracking data for multiple species of Antarctic meso- and top-predators to identify Areas of Ecological Significance. These datasets and accompanying syntheses provide a greater understanding of fundamental ecosystem processes in the Southern Ocean, support modelling of predator distributions under future climate scenarios and create inputs that can be incorporated into decision making processes by management authorities. In this data paper, we present the compiled tracking data from research groups that have worked in the Antarctic since the 1990s. The data are publicly available through biodiversity.aq and the Ocean Biogeographic Information System. The archive includes tracking data from over 70 contributors across 12 national Antarctic programs, and includes data from 17 predator species, 4060 individual animals, and over 2.9 million observed locations. Publisher PDF

Incidences of cryo-benthic communities beneath ice shelves are rare and recent discoveries. Combined seal- and ROV-borne imagery and novel sampling technologies allowed for a re-assessment and augmentation of earlier findings on a cryo-benthic isopod community (Antarcturus cf. spinacoronatus), being attached head-down to the underside of floating shelf ice at depths of around 80-150m. The shelf ice-associated cryo-benthos was discovered at Drescher Inlet (-72.83667 -19.15300), Riiser-Larsen Ice Shelf (eastern Weddell Sea). The inlet constitutes a 25km long and between 2 and 4km wide crack in the surrounding shelf ice, which is associated with certain environmental features. Here we compile all available local physical, biological, and biogeochemical data and discuss their relevance in the wider regional context for this faunal hotspot. These include data on shelf, sea and platelet ice, seafloor topography, hydrography and water chemistry, as well as associated pelagic and benthic marine life, in particular affinities of the cryo-benthic isopod community to related fauna occurring in nearby seabed communities using molecular barcoding.

The Weddell seal (Leptonychotes weddellii) inhabits the Antarctic coastal ecosystem and aggregates in areas characterized by a stable fast ice layer. Due to their extreme diving capabilities, they are able to exploit both pelagic and benthic prey resources. They mainly feed on fishes but occasionally also take cephalopods and crustaceans. Weddell seals instrumented with still-picture camera loggers in the Drescher Inlet, eastern Weddell Sea, detected an unknown cryo-benthic community underneath the floating ice shelf. Images show dense aggregations of invertebrates that likely represent an attractive food horizon for Weddell seals. In this context, we conducted a retrospective analysis of dive profiles collected in the Drescher Inlet to identify favoured hunting depths of Weddell seals and correlate those to the local physical and biological environment. A total of 34 adult Weddell seals were instrumented with dive loggers in the course of six summer field campaigns between 1990 and 2016. An automated broken stick algorithm was used to separate each dive profile into different segments. Segments with a high sinuosity were considered to indicate hunting. Segments characterized by a straight dive trajectories (low sinuosity), were assumed to be transit phases with no hunting activities. A tri-modal distribution of mean hunting depths suggests that Weddell seals concentrated their foraging activities in three depth strata. A peak in hunting depths below 370 m corresponds to the sea floor of the Drescher Inlet, indicating demersal foraging. A second peak between 110 and 160 m matches with the depth of the underside of the floating ice shelf, which suggests shelf ice associated foraging. The third peak probably represents hunting in the pelagic realm. Our investigation highlights the importance of the shelf ice underside as an attractive food horizon for Weddell seals suggesting a re-evaluation of trophic interactions and bentho-pelagic processes in the coastal Antarctic ecosystem.

Over the last decade, several hundred seals have been equipped with conductivity-temperature-depth (CTD) sensors in the Southern Ocean for both biological and physical oceanographic studies. A calibrated collection of seal-derived hydrographic data is now available, consisting of more than 165,000 profiles. The value of these hydrographic data within the existing Southern Ocean observing system is demonstrated herein by conducting two state estimation experiments, differing only in the use or not of seal data to constrain the system. Including seal-derived data substantially modifies the estimated surface mixed-layer properties and circulation patterns within and south of the Antarctic Circumpolar Current. Agreement with independent satellite observations of sea-ice concentration is improved, especially along the East Antarctic shelf. Instrumented animals efficiently reduce a critical observational gap, and their contribution to monitoring polar climate variability will continue to grow as data accuracy and spatial coverage increase. Publisher PDF

Bio-logging systems are a useful tool for understanding the behavior of marine mammals and their environmental conditions.In particular, accelerometer data provide characteristic information on feeding events, posture and body movement of the animals. Naito et al. (2010) reported on acceleration patterns of feeding behavior and unknown acceleration patterns of jaw motion of two free-ranging adult female Weddell seals (No. 06 and No.16) instrumented in Atka Bay (70º39’S, 08º15’W) in early December 2008. Although acceleration pattern of feeding behaviour was inferred by data obtained from the feeding experiments of captive seals, acceleration pattern of non-feeding behaviour has never been examined in detail. Here we re-examined those data【depth (±0.1m), environmental temperature (±0.1℃), and two way acceleration, heave(x) and surge (y) data at 32Hz were measured over three days】to obtain new insight into the behaviour of the species. We detected low frequency cycle with attenuating pattern from two adult female Weddell seals. Individual (No.06) and (No.16) showed average cycle of 0.217±0.007 sec. and 0.161±0.008 sec., average duration of 4.43±0.225 sec. and 4.08±0.68 sec., and average depth of 2.06±0.42 m and 6.21±1.19 m, respectively. We isolated 135 events in 269 dives of the seal (No.06) and 29 events in 167 dives of the seal (No.16). It is well known that Weddell seals produce a number of vocalizations at shallow depths during breeding season and these vocalizations assumed to be related to mating behaviour. However, frequency of our data was lower than that of usual vocalization. Although the function of this low frequency pattern is still unknown, we hypothesize that low frequency pattern emitted by shivering some parts of lower jaw (or laryngeal organ) have an unknown function like “social call-interaction” during the breeding season.

Deployments of ARGOS satellite transmitters on adult southern elephant seal males at King George Island in 2010 represent a follow-up study of an earlier project in 2000/2001. Males had either moved along the Bransfield Strait and around the tip of the Antarctic Peninsula or deep into the winter pack ice of the southern Weddell Sea. The latter finding could not be reproduced, though seals travelled on comparably extended latitudinal gradients between King George Island / Isla 25 de Mayo and South Georgia or the southern Bellingshausen Sea. The recent movements seem to contradict patterns of sexual segregation interpreted from earlier studies, suggesting more overlap between foraging grounds of adult males and females then previously assumed. As far as we could track individuals, most post-moult movements were oriented to South Georgia towards the breeding season and back thereafter. The seals' long and straight line movements at distances of more than 1500 km allowed for cross sectional analyses of hydrographic features and revealed information on the temperature and salinity regime during winter. All seals showed extended residence times at specific circumscribed at-sea locations, considered as foraging hot spots. These spots were widely distributed within the Bellingshausen and northern Weddell Seas and seem to be linked to bathymetric features, such as slopes, seamounts or plateaus. The study involves scientists from South Africa (MRI), Argentina (IAA) and Germany (AWI) in a synoptic approach of the investigation of the movement behaviour of southern elephant seals from King George Island and Marion Island, and highlights our long-time collaboration within the "Year of Science" of South Africa and Germany in 2012/13.

The development of models of marine ecosystems in the Southern Ocean is becoming increasingly important as a means of understanding and managing impacts such as exploitation and climate change. Collating data from disparate sources, and understanding biases or uncertainties inherent in those data, are important first steps for improving ecosystem models. This review focuses on seals that breed in ice habitats of the Southern Ocean (i.e. the crabeater seal, Lobodon carcinophaga; Ross seal, Ommatophoca rossii; leopard seal, Hydrurga leptonyx; and Weddell seal, Leptonychotes weddellii). Data on populations (abundance and trends in abundance), distribution and habitat use (movement, key habitat and environmental features) and foraging (diet) are summarised, and potential biases and uncertainties inherent in those data are identified and discussed. Spatial and temporal gaps in knowledge of the populations, habitats and diet of each species are also identified.

Satellite-relay data loggers (SRDLs) were deployed on southern elephant seals hauled out at Marion Island as part of the International Polar Year project, Marine Mammal Exploration of the Oceans Pole to Pole (MEOP). We describe the dive behaviour responses of one male elephant seal to changes in oceanographic conditions during two post-moult migrations. The seal concentrated his diving activity in a small area (

The region around the sill of the Filchner Trough outflow (77°S, 36°W) is considered a hot spot, both in terms of biology and physical oceanography. The factors contributing to this oceanic area of enhanced food availability and its relation to physical processes are not yet understood. Animal-borne satellite telemetry of southern elephant seal males, instrumented at King George Island / Isla 25 de Mayo aims to describe the seals' preferred foraging depths around the Filchner Trough in order to elucidate the vertical distribution of prey in relation to the oceanographic features on-site. Recent deployments (2010) represent a follow-up study of an ARGOS satellite telemetry project on elephant seals in 2000. Adult males travelled deep into the winter pack ice of the Weddell Sea along the western continental shelf break until they reached the region of the sill of the Filchner Trough outflow, where they remained in a localized 100 km wide shelf-slope area for several months. The re-instrumentation aims to investigate if males continue to travel to similar areas. The trilateral, long-term observation study of scientists from South Africa, Argentina and Germany is based on a synoptic approach for Marion Island and King George Island / Isla 25 de Mayo.

The International Society for Burns Injuries (ISBI) has published guidelines for the management of multiple or mass burns casualties, and recommends that 'each country has or should have a disaster planning system that addresses its own particular needs.' The need for a national burns disaster plan integrated with national and provincial disaster planning was discussed at the South African Burns Society Congress in 2009, but there was no real involvement in the disaster planning prior to the 2010 World Cup; the country would have been poorly prepared had there been a burns disaster during the event. This article identifies some of the lessons learnt and strategies derived from major burns disasters and burns disaster planning from other regions. Members of the South African Burns Society are undertaking an audit of burns care in South Africa to investigate the feasibility of a national burns disaster plan. This audit (which is still under way) also aims to identify weaknesses of burns care in South Africa and implement improvements where necessary.

Seals are supposed to forage in efficient manner during dives due to strict physiological constraints. Understanding of foraging behavior is essential for a comprehensive understanding of overall diving behavior. Although several techniques of measuring feeding behavior have been developed, direct measurement of feeding efficiency has not been made. Simultaneous measurement of feeding rate and effort is essential to study feeding efficiency. In order to develop simultaneous measurement of feeding events and effort (swim stroke) we tested a new mandible accelerometer method on free ranging Weddell seals in the Atka Bay, Eckstroem Ice Shelf, Antarctica in November/December 2008. Before to conduct the field test on Weddell seals, we attached the accelerometers (D2GT; 15mm in diameter, 53mm in length, 18g in air, Little Leonardo, Tokyo) on the mandible of captive harp seals. The experiment showed that frequency filtered signal (Igor Filtering Design Laboratory: IFDL WaveMetrics, Lake Oswego, OR U.S.A.) of acceleration from the mandible is quite distinct at moments of prey ingestion allowing us to use mandible accelerometer for the detection of feeding events of seals in the wild. We attached the same accelerometers equipped with two sensors (surge and heave axes) on the mandible of Weddell seals to detect movements associated with feeding and also swim activities. We successfully obtained feeding data together with stroke and depth data. Here we report the results of the diving behavior and foraging success of Weddell seals in Antarctica.

Based on body size dimorphism, southern elephant seals from Marion Island were expected to display significant differences betweensexes in depth use while at sea. We instrumented 53 adult and sub-adult animals of both sexes with satellite-relay data loggers(SMRU) between 2004 and 2008. These devices transmitted basic dive data, as well as location and temperature data while theinstrumented animals were at sea. Using a simple calculation, we determined time spent by individual animals in various depthcategories during a total of 182 882 dives. Animals of both sexes targeted depths between 300m and 600m more than other depthcategories, and substantial overlap between sexes was recorded for time spent in depths between 500m and 600m. Male elephantseals however targeted and spent significantly more time in depths between 600m and 1250m (p < 0.05). Female elephant sealstargeted and spent significantly more time in depths between 200m and 500m (p < 0.05). No significant differences were recorded fordepth use between adult and sub-adult males. The overlap in mid-water depth use by both sexes suggests that the limited segregationobserved in depth use by southern elephant seals from Marion Island is likely driven by different physiological capabilities, and notforage selection or predator avoidance.

Emperor penguins, Aptenodytes forsteri, play an important role as top predators in high Antarctic marine ecosystems. Being a central place forager the emperor penguin executes foraging trips to remote locations but consistently returns to a central place, the colony, to deliver food to the chick. The present study focuses on the critical two month-period before fledging, when maximum growth of chicks occurs and food demand is high at the Pointe Géologie emperor penguin colony. Using satellite telemetry we identified the foraging distribution and feeding grounds during late chick-rearing and before the adult moult in comparison. Depth records in addition allowed us to examine the diving behaviour at sea. Horizontal and vertical extent of penguin movement is here described over a single foraging trip in November 2005. The Area-Restricted-Search (ARS) (derived from the total distance spent travelling underwater over a defined time interval divided by the straight-line horizontal distance travelled during that period) and the Catch Per Unit Effort (CPUE) (derived from the putative number of prey caught (defined by points of inflections in the dive trace) divided by the time spent underwater) indices are used as a measure for the foraging activity to examine how birds allocate time to foraging in certain areas.

Marine mammals rely on sound and hearing as their primary means of communication and sensing their world. Concerns that anthropogenic sound in the ocean could infer their sensing, cause stress or even damage their hearing physically rose a controversial discussion and triggered a worldwide boost in marine bioacoustic research. Innovative acoustic technologies and field methods are required to provide a basis for carefully designed and technically challenging research projects on free-ranging marine mammals, especially under the harsh environmental conditions of polar regions. The Ocean Acoustics group within the Marine Observing Systems section endeavors multidisciplinary research of environmental scientists, geophysicists, oceanographers, physicists, physiologists, and biologists to investigate the need and scope of mitigation measures for the effects of man-generated sound in the ocean, develop acoustic census techniques, explore marine mammal responses to various anthropogenic sounds, and study the vocal behaviour and hearing physiology of Antarctic marine mammals.

Emperor penguins, Aptenodytes forsteri, play an important role as top predators in high Antarctic marine ecosystems. Long foraging cycles enable chick-rearing birds to range widely in their quest for food. The present study focuses on the critical two month-period before fledging, when maximum growth of chicks occurs and food demand is high at the Pointe Géologie emperor penguin colony of about 3000 breeding pairs. Objectives were to identify the foraging distribution and feeding grounds by satellite tracking chick-rearing penguins, determine the length and duration of feeding trips, to characterise the pattern of movements and diving relative to the bottom topography and sea ice distribution and to examine the diet of emperor penguins.