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  • This parameter set was developed to provide a plausible implementation for the ecological model described in Bates, M., S Bengtson Nash, D.W. Hawker, J. Norbury, J.S. Stark and R. A. Cropp. 2015. Construction of a trophically complex near-shore Antarctic food web model using the Conservative Normal framework with structural coexistence. Journal of Marine Systems. 145: 1-14. The ecosystem model used in this paper was designed to have the property of structural coexistence. This means that the functional forms used to describe population interactions in the equations were chosen to ensure that the boundary eigenvalues of every population were all always positive, ensuring that no population in the model can ever become extinct. This property is appropriate for models such as this that are implemented to model typical seasonal variations rather than changes over time. The actual parameter values were determined by searching a parameter space for parameter sets that resulted in a plausible distribution of biomass among the trophic levels. The search was implemented using the Boundary Eigenvalue Nudging - Genetic Algorithm (BENGA) method and was constrained by measured values where these were available. This parameter set is provided as an indicative set that is appropriate for studying the partitioning of Persistent Organic Pollutants in coastal Antarctic ecosystems. It should not be used for predictive population modelling without independent calibration and validation.

  • Metadata record for data from ASAC Project 2753 See the link below for public details on this project. Public Weddell and southern elephant seals are high-order predators living in the Antarctic marine ecosystem. Their place in that ecosystem is the result of a long history of evolutionary adaptation to a challenging and changing environment. The objective of this study is to understand how Weddell and elephant seals have adapted and are responding to today's rapidly changing Antarctic environment. This study will use current and innovative approaches in demographic (population) analyses and diet techniques to analyse changes in the seals' demographic parameters and historical aspects of their ecology. Project objectives: Objective 1. Seek a greater understanding of the links between climate based environmental parameters and Weddell seal demographic performance. Objective 2. Test the hypothesis that the foraging ecology and presence of male southern elephant seals hauling out along the Antarctic coast are regulated by variation in the extent and concentration of coastal sea-ice. Objective 3. Examine contemporary and historical dietary shifts in an Antarctic marine predator by using a non-invasive technique, stable isotope analyses. Objective 4. Construct models of potential population performance for Weddell and southern elephant seals with predicted climate change Taken from the 2008-2009 Progress Report: Progress against objectives: The first season of field work was conducted at Casey in December 2008. This comprised of surveys of the region to locate breeding and moulting haulouts, weighing and flipper tagging of Weddell seal pups and flipper tagging of sub adult elephant seals. Specifically: Tagging Leptonychotes weddellii. A total of 30 pups were flipper tagged. Tagging: 46 sub-adult male Mirounga leonina in Browning Peninsula region. Aerial survey of the Casey fast-ice conducted on 30/1/2009. Conducted at 1000, 500, 300 ft. A total of 33 seals counted. Taken from the 2009-2010 Progress Report: Progress against objectives: 1. Observations of tagged Weddell seals made in the Vestfold Hills during the breeding season. 2. Counts were made of elephant seals at Davis station 3. No progress made due to postponement of project at Casey 4. Data collected on Weddell and elephant seals at Davis. No modelling undertaken in this year

  • The ‘Logger’ data entry system was developed by the International Fund for Animal Welfare (IFAW) and is a flexible system to record information during a voyage. All events occurring during daylight operations such as sightings, biopsy attempts and sonobuoy deployments were recorded in a customized data entry program Logger along with weather and effort data. The logger access database contains all data collected throughout theNZ/Aus Antarctic Ecosystems Voyage 2015 related to: Biopsy events (date/time in UTC, success, sample number, reaction, attempts, dart recovery, notes) Comments - time stamped (UTC) with GPS index providing additional detail Observer effort (effort status, event, number of observers and locations, ship guide and data logger) Environmental observations (sightability, sea state, swell, weather, cloud cover, visibility, intensity, glare, ice, sea surface temperature) GPS data - time indexed NMEA feed, also containing heading and ship speed Lookup - table containing topic codes describing the codes that appear in all other tables Cetacean sightings and resightings (date/time in UTC), sighting number, sighting platform, estimate distance, binocular reticles, angle, species, sighting cue, heading, estimate of number of individuals, observer of sighting, behaviour, pod compaction, comments) Sonobuoy deployments (date/time in UTC, sonobuoy number, notes)

  • Biopsy samples were collected from humpback (n=10) and blue whales (n=1) during the NZ/Aus Antarctic Ecosystems Voyage 2015. Biopsy collection from humpback and blue whales was attempted from the bow of the ship using Larsen rifles. Biopsying blue whales from the bow of the RV Tangaroa proved challenging due to the ship’s manoeuvrability and the limited capacity to change speed rapidly. Biopsy samples were split between All Protect (Qiagen), 70% ethanol, and freezing at -20C. . This dataset consists of an excel spreadsheet (biopsy_events.xlsx) summarising biopsy events containing the fields: Date_taken (in UTC) Location (general) where sample collected Latitude Longitude Individual ID Sample ID Name of sampler Sample type Preservative used Species sampled An excel spreadsheet (Biopsy sample info datasheet AEV 2015.xlsx) details the biopsy processing that occurred upon collection of a sample. Where possible, each sample was split and preserved in 2 x All Protect, 1 x EtOH and 1 x -80 degrees Celsius. Samples preserved in All Protect and 70% ethanol are stored at the Australian Antarctic Division and samples preserved at -80C are stored at NIWA Wellington. A subsample of the Antarctic blue whale biopsy was submitted to the IWC-recognised genetic repository for Antarctic blue whale at NOAA Southwest Fisheries, La Jolla. Biopsy samples were processed to determine sex and the results are held in: TAN1502_Whale biopsy samples.xls

  • Infaunal marine invertebrates were collected from inside and outside of patches of white bacterial mats from several sites in the Windmill Islands, Antarctica, around Casey station during the 2006-07 summer. Samples were collected from McGrady Cove inner and outer, the tide gauge near the Casey wharf, Stevenson's Cove and Brown Bay inner. Sediment cores of 10cm depth and 5cm diameter were collected by divers using a PVC corer from inside (4 cores) and outside (4 cores) each bacterial patch. The size of each patch varied from site to site. Cores were sieved at 500 microns and the extracted fauna preserved in 4 percent neutral buffered formalin. All fauna were counted and identified to species where possible or assigned to morphospecies based on previous infaunal sampling around Casey. An excel spreadsheet is available for download at the URL given below. The spreadsheet does not represent the complete dataset, and is only the bacterial mat infauna data. Regarding the infauna dataset: - in - in the mat or patch of bacteria and out is in the "normal" sediment surrounding the patch without evidence of any bacterial mat presence. - Patch numbers were allocated to ensure there was no confusion between patches in the same area. - Fauna names are our identification codes for each species. Some we have confirmed identifications for, some not. Species names, where we have them and as we get them, are listed against these codes in the Casey marine soft-sediment fauna identification guide. This work was completed as part of ASAC 2201 (ASAC_2201).