Metadata record for data expected from ASAC Project 2940 See the link below for public details on this project. Public: The extent of Antarctic winter sea-ice influences all aspects of the Antarctic marine food-web. We will use natural variations in inter-annual ice extent, to assess how a key component of that ecosystem, the predators, use the sea ice zone. Core foraging areas and dietary signals for a key Antarctic predator (Antarctic fur seal) will be identified. We will use newly developed, technology to track the animals, and stable isotopes to examine tropic linkages. Combined with satellite-derived sea-ice data, this will lead to the development of a model to predict how changing sea-ice patterns will influence Antarctic marine predator communities. Project Objectives: 1. Use large samples of newly-developed (and tested) animal-borne miniature geolocating light level recorders to population level information on the spatial extent of movements of Antarctic fur seals, thereby quantifying the extent of the use of the winter pack-ice and associated waters by these abundant predators. 2. To quantify how changes in winter ice extent influence the location of core foraging areas for this species. 3. To develop models to investigate how changing ice conditions in the future will influence the movements of this species and to examine a range of climate-change scenarios. Taken from the 2007-2008 Progress Report: No field work was conducted at Macquarie Island in the last 12 months. This was due to the decision by the state government to not issue permits for the work. With the help of our colleagues from BAS we did however manage to deploy 20 GLS light loggers on Antarctic fur seals at South Georgia. Taken from the 2008-2009 Progress Report: Objective 1 has been revised to the study of Antarctic fur seals only (see below). Research is progressing well with 78 animals tracked in 2008 and a further 80 expected in 2009. Objectives 2 and 3 will follow once field data is available for both years (May 2010). Isotopic analysis of blood and whisker samples for the 2008 season will commence in May 2009 once samples have been received. Taken from the 2010-2011 Progress Report: Public summary of the season progress: This study has quantified the response of the Antarctic fur seal (Arctocephalus gazella) to inter-annual variation in oceanographic and winter ice conditions. We have measured the winter spatial foraging patterns of 66 adult females from three circum-Antarctic populations over two years (2008, 2009) during 114 trips to sea, while simultaneously recording in situ water temperature. Stable isotope analysis of fur seal blood and whisker samples indicates that adult females feed on a range of lower (krill) to higher (fish and squid) trophic levels across their winter range. Broad-scale habitat preferences across the range of the species indicate the importance of shelf, ice edge, frontal and oceanic and continental upwelling features in determining winter foraging movements.

This study was carried out by Giulia Roncon as part of her PhD at IMAS. The study employed both archival and contemporary diving data, collected by six species of marine predators (three penguins and three seal species) from the Eastern Antarctic sector of the Southern Ocean, to clarify key questions, such as (i) are there differences and/or commonalities regarding the diving physiology and ecology of marine predators, and (ii) what are the main determinants and constrains that characterise the underwater behaviour of air-breathing vertebrates. This dataset is a compilation of data of several different studies carried out by different research teams in various locations and at various times. All TDRs were archival loggers that had to be retrieved to obtain the data. Thus, the animals had to be captured twice (deployment and retrieval). Details about the types of tags are listed in the dataset. Species used in the study were: Adelie Penguins Emperor Penguins King Penguins Fur Seals Southern Elephant Seals Weddell Seals

From the abstract of the referenced paper: Satellite telemetry data are a key source of animal distribution information for marine ecosystem management and conservation activities. We used two decades of telemetry data from the East Antarctic sector of the Southern Ocean. Habitat utilization models for the spring/summer period were developed for six highly abundant, wide-ranging meso- and top-predator species: Adelie, Pygoscelis adeliae and emperor, Aptenodytes forsteri penguins, light-mantled albatross, Phoebetria palpebrata, Antarctic fur seals, Arctocephalus gazella, southern elephant seals, Mirounga leonina, and Weddell seals, Leptonychotes weddellii. The regional predictions from these models were combined to identify areas utilized by multiple species, and therefore likely to be of particular ecological significance. These areas were distributed across the longitudinal breadth of the East Antarctic sector, and were characterized by proximity to breeding colonies, both on the Antarctic continent and on subantarctic islands to the north, and by sea-ice dynamics, particularly locations of winter polynyas. These areas of important habitat were also congruent with many of the areas reported to be showing the strongest regional trends in sea ice seasonality. The results emphasize the importance of on-shore and sea-ice processes to Antarctic marine ecosystems. Our study provides ocean-basin-scale predictions of predator habitat utilization, an assessment of contemporary habitat use against which future changes can be assessed, and is of direct relevance to current conservation planning and spatial management efforts. The data files provided here comprise the model predictions of the preferred habitat for each of the six species listed above, as well as the overlap results obtained by combining these six sets of results. See the paper for methods used to generate the model predictions and to combine the individual species results. File names for individual species are of the form results_SPP_TYPE.asc, where SPP is one of "afs" (Antarctic fur seal), "ap" (Adelie penguin), "ep" (emperor penguin), "lma" (light-mantled albatross), "ses" (southern elephant seal), or "ws" (Weddell seal. TYPE is either "mean" (mean estimate of habitat preference) or "iqr" (inter-quartile range of uncertainty in the estimate; see paper for details). Data values for individual species results are percentiles of the study area, so that values of 90% or higher are pixels corresponding to the most important 10% of habitat for that species, values of 80% or greater are the top 20% of habitat, and so on. The overlap results files are named overlay_results_mean.asc and overlay_results_iqr.asc. Values in these files represent the average of the top four individual species results in a given pixel (see paper for details).

Gentoo penguins are the least numerous of the penguins breeding at Macquarie Island, and the only species to rear two chicks. This project examined the interactions between diving behaviour, diet and reproductive strategy. Data were collected on Time Depth Recorders (TDRs), and stored in hexadecimal format. Hexadecimal files can be read using 'Instrument Helper', a free download from Wildlife Computers (see the url given below).

This dataset is a collection of presence-absence and %occurrence data of prey species found within scats of Hooker Sea Lions. The data are presented in an excel spreadsheet. Samples were collected from 54 scats. From the abstract of the referenced paper: Scats were collected from itinerant male Hooker's sea lions, Phocarctos hookeri, at Macquarie Island and the un-eroded faunal remains used to assess the diet. Un-eroded sagittal otoliths were used to identify teleost fish and to calculate fish size. Prey items included 14 taxa of teleost fish, cephalopods, gastropods, crustaceans and fur seals. Fish constituted the primary component of the diet. Prey species previously uncommon in the diet of seals and penguins around Macquarie Island were commonly eaten by Hooker's sea lions. The sub-Antarctic horse fish (Zanclorhynchus spinifer) and the Patagonian tooth fish (Dissostichus eleginoides) were the two most abundant species and occurred in 62.5% and 41.7% of all scats respectively. There were no age specific and individual differences in the diet of sea lions. Seasonal variances in diet were absent. Small plastic fragments (diameter ~ 1mm) were only found in association with Electrona subaspera otoliths. Some overlap was seen between the diet of itinerant male Hooker's sea lions and the commercial fisheries that currently occur around Macquarie Island. This work was completed as part of ASAC project 2265 (ASAC_2265).

This dataset is a document describing the Decapoda of the Southern Ocean. It lists all the known species and with illustrated diagrams provides a guide to their taxonomic identification. The document is available for download as a pdf from the provided URL.

Metadata record for data from ASAC Project 2794 See the link below for public details on this project. Public: This study will use innovative technology to measure the winter spatial foraging patterns and net energy gain of adult female elephant seals (and potentially Weddell seals), while simultaneously providing high-resolution data on the physical nature of the water column in which the seals live. By combining biological and physical data with satellite derived sea-ice information, this study will improve our understanding of predator foraging success (and therefore mechanisms which regulate population trajectories) and provide physical oceanographers with fundamental data on the importance mechanisms that determine the winter ice and bottom water formation that under-pin the Antarctic marine ecosystem. Project objectives: The extent and nature of Antarctic winter sea ice is thought to have profound impacts on biological productivity, the recruitment of Antarctic krill, and the flow-on effects through the Antarctic marine food web. 1. Winter sea-ice formation is also hypothesised to play an important, yet highly-variable role in ocean circulation patterns through the production of cold, dense winter bottom water. 2. The mechanisms determining the inter-annual variation in winter ice formation are poorly understood, as are the complex feedback processes involved, but they are nonetheless recognised as being vulnerable to human-induced climate change. 3. Given the dynamically-linked nature of winter-ice and biological productivity, long-term climatic changes will have broad scale influences on Antarctic biota. This study will use innovative technological developments to quantify the response of one of the major Antarctic marine predators, the southern elephant seal (Mirounga leonina), to inter-annual variation in winter ice conditions. We will measure the winter spatial foraging patterns and net energy gain of adult female elephant seals while simultaneously providing high-resolution data on the physical nature of the water column in which the seals are living. The combination of these biological and physical data with satellite-derived sea-ice information will relate variation in the winter-ice to broad scale biological production through the foraging success (maternal investment and therefore demographic performance) of a top Antarctic marine predator, as well as providing physical oceanographers with fundamental data on the important mechanisms that determine the winter ice and bottom water formation that under-pin the Antarctic marine ecosystem. The specific objectives are to: Measure the foraging performance of the seals in terms of spatially-specific net energy gain while at sea, in relation to intra- and inter-annual variation in sea-ice and oceanic processes. Use newly-developed (and tested) animal-borne satellite-linked Conductivity-Temperature-Depth Satellite Relay Data Loggers (CTD-SRDLs) to provide oceanographic quality data on local physical characteristics (temperature and salinity). Record fine-scale foraging parameters (dive depth, duration, swimming speed) using "Dead-Reckoning" Data Loggers (DRDLs) and feeding events using Stomach Temperature Sensors (STSs). Integrate these data collected in years and regions of different winter ice extent and conditions. Assess diet during the winter months using stable isotope and fatty acid signature analysis. Combine the biological and physical information to refine current models of predator performance based on annual climatic features. These models will be used to examine a range of climate-change scenarios, initially for elephant seals but with a view to broadening the species application at a later stage. Taken from the 2008-2009 Progress Report: Progress against objectives: Due to logistic constraints, no satellite telemetry was conducted at Casey or Macquarie Island this year, but preliminary surveys of the region were conducted for both elephant and Weddell

Metadata record for data expected from ASAC project 131 (ASAC_131). Taken from the referenced publication: The diet of Heard Island cormorants was investigated by examination of casts over three summer seasons. The diet was composed of mainly benthic organisms, with polychaetes being the most common prey for the greater part of the population. Fish were taken commonly only by the small breeding population at the western end of the island, whereas elsewhere only 22% of casts contained any fish remains at all. The diet is therefore different from that reported for Phalacrocorax atriceps at other localities.

Metadata record for data from ASAC Project 257 See the link below for public details on this project. From the abstracts of some of the referenced papers: Anatomical and physiological studies of southern elephant seals (Mirounga leonina), particularly in the post-natal period, raise questions of relative musculature growth, control of metabolism, circulation and temperature regulation, which could be important in our understanding of these processes in mammals and of their contribution to adaptation to environmental extremes. The diving behaviour of 14 adult southern elephant seals was investigated using time depth recorders. Each of the seals performed some dives that were longer than its theoretical aerobic dive limit. Forty-four percent of all dives made by post-moult females exceeded the calculated limit compared with 7% of those made by postbreeding females and less than 1% of those made by adult males. The extended dives displayed characteristics that suggested they were predominantly foraging dives, although some were apparently rest dives. Dives longer than the calculated aerobic limits often occurred in bouts; the longest consisted of 63 consecutive dives and lasted 2 days. Postmoult females performed longer bouts of extended dives than postbreeding females. Extended surface periods (longer than 30 min) were not related to the occurrence of extended dives or bouts of extended dives. The possible physiological mechanisms that permit such prolonged continuous dives are discussed. Southern elephant seals may increase the aerobic capacity of dives by lowering their metabolism to approximately 40% of the resting metabolic rate on long dives. There is substantial interseal variability in the methods used to cope with long dives. Some animals appear to use phsyiological strategies that allow them to prolong the time available to them at the bottom of a dive, while others use alternative strategies that may limit the time available at the bottom of their dives. Fourteen time-depth-temperature recorders were recovered from adult southern elephant seals (Mirounga leonina) returning to Macqaurie Island to breed or moult. The resulting temperature/depth profiles indicated that all four males spent most of their time in waters lying over the Antarctic Continental Shelf, whereas only one of the ten females spent any time there. Five of the females foraged just off the Antarctic Continental Shelf, and the other five remained near the Antarctic Polar Front. 1) Mark-resight data were analysed for thirteen cohorts from a declining population of southern elephant seals branded at Macquarie Island between 1951 and 1965. 2) First year survival was essential stable during the 1950s at about 46% for females and 42% for males. There was a dramatic fall in first year survival during the 1960s, declinging to less than 2% for both sexes in 1965. Post-year-1 survival did not change between the 1950s and the 1960s. 3) Comparisons with a stable population of southern elephant seals at South Georgia indicated that both first year and adult survival were lower in the Macquarie Island population. There were no changes in the age at first breeding of the Macquarie Island seals during the study, but this was on average 1 year later than at South Georgia. 4) It is hypothesised that the current decline in elephant seal numbers at several of their major breeding islands is due to the populations returning to pre-sealing levels after they had risen to abnormally high levels with the end of commercial exploitation early this century. 5) Possible tests of the hypothesis include studying the diet and foraging behaviour of southern elephant seals to gain an understanding of the predator-prey relationships, continuing to census the Macquarie Island population to determine if the population levels out at around the estimated pre-sealing levels, and monitoring northern elephant seal populations which were also severely exploited but are currently increasing

This dataset is a document describing the Chaetognaths of the Southern Ocean. The synonymy, diagnostic characters, geographical and bathymetric distribution of each species is given together with an illustration of body, head and a seminal vesicle, and a distribution map. The document is available for download as a pdf from the provided URL.