Keyword

EARTH SCIENCE > BIOSPHERE > ECOLOGICAL DYNAMICS > SPECIES/POPULATION INTERACTIONS > USE/FEEDING HABITATS

30 record(s)
 
Type of resources
Topics
Keywords
Contact for the resource
Provided by
From 1 - 10 / 30
  • These data represent the results of the first study to use Earth System Model (ESM) outputs of SST and chlorophyll-a to simulate circumpolar krill growth potential for the recent past (1960-1989) and future climate change scenarios (2070-2099). Growth potential is obtained using an empirically-derived krill growth model (Atkinson et al. 2006, Limnol. Oceanogr.), where growth is modeled as a function of SST and chlorophyll-a. It serves as an approximation of habitat quality, as areas that support high growth rates are assumed to be good habitat (see Murphy et al., 2017, Sci Rep). To increase confidence in the future projections, ESMs were selected and weighted for each season based on their skill at reproducing observation-based krill growth potential for the recent past. First, eleven ESMs which provided SST and chlorophyll-a outputs were obtained from the Coupled Model Inter-comparison Project 5 archive. These included: CanESM2, CMCC-CESM, CNRM-CM5, GFL-ESM2G, GFDL-ESM2M, GISS-E2-H-CC, HadGEM2-CC, IPSL-CM5A-LR, MPI-ESM-MR, MRI-ESM1 and NorESM1-ME. For each ESM, seasonal surface averages of SST and chlorophyll-a were used to calculate growth potential for the historical scenario (1960-1989), which was then bilinearly interpolated on to the same 1°x1° grid. Satellite observation-based datasets for SST and chlorophyll-a were used to calculate observation-based growth potential for the recent past (1997-2010). These comprised seasonal surface averages of SST (from the OISST v2 daily dataset, 1/4⁰ horizontal resolution) and chlorophyll-a (the mean of the SeaWiFS and Johnson et al. (2013) corrected estimate of SeaWiFS daily datasets, 1/12⁰ horizontal resolution). Observation-based growth potential was then bilinearly interpolated onto the same grid as the ESMs. ESM skill for each season was subsequently assessed against observation-based growth potential using a Taylor Diagram. The ESMs were selected and weighted according to their performance to produce a weighted subset (see "ESM_weighting_method.pdf" file). Of the netcdfs provided, "hist_mean_ensemble.nc" represents the unweighted mean of seasonal growth potential, calculated from the initial ensemble of eleven ESMs for the historical scenario. The "hist_mean_subset.nc" file represents the analogous output of the weighted subset. Future projections of seasonal growth potential for Representative Concentration Pathways (RCPs) 4.5 and 8.5 were obtained using the weighted subset for the period of 2070-2099. These projected seasonal surface averages are provided in the "rcp45_mean_subset.nc" and "rcp85_mean_subset.nc" files. RCPs represent standard climate change scenarios developed by the Intergovernmental Panel on Climate Change, with 4.5 reflecting some mitigation of carbon emissions, and 8.5 being the "business as usual" scenario. Analogous netcdfs for the weighted subset outputs of chlorophyll-a (chl) and SST (tos) for the historical and RCP scenarios are also provided in the "chl_tos_netcdfs.zip" file so that the driving environmental variables underlying growth potential can be examined.

  • As seabirds emperor penguins spent a large proportion of their lives at sea. For food they depend entirely on marine resources. Young penguins rarely return to their natal colonies after their first year. Satellite tracking will give us insights into where foraging areas may be that are important for these birds. This tracking work is part of a multi-species study funded by the Integrated Marine Observation System (IMOS). These data are from penguins from the Amanda Bay area, and for the 2012-13 season.

  • An R data file containing a hierarchical switching state-space model of pygmy blue whale Argos-collected telemetry data using the bsam package (see Jonsen (2016). Joint estimation over multiple individuals improves behavioural state inference from animal movement data. Scientific Reports 6: 20625.) in R. The model estimated location states for each individual at regular 3-h time intervals, accounting for measurement error in the irregularly observed Argos surface locations; and estimated the behavioural state associated with each location. Satellite tags were deployed on pygmy blue whales located in the Bonney Upwelling region, SA, between 7 January and 16 March 2015. File can be opened in R (A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/ ) using the code: readRDS('bw_3h_ssm.RDS')

  • June 2018 Adélie penguin scats were collected from Signy Island (South Orkney Islands) during crèche (December/January) 2014/15 and 2015/16 and stored in 80% Ethanol. DNA was extracted from ~30 mg of faecal material using a Promega ‘Maxwell 16' instrument and a Maxwell® 16 Tissue DNA kit. A total of 450 samples were analysed: 30 extractions per week for 2015 and 60 per week for samples collected in 2016. Three DNA markers providing different taxonomic information were amplified from penguin faecal DNA. First, ALL faecal DNA samples were characterised using a highly conserved metazoan primer set that amplifies a region of the nuclear 18S gene. In addition, a subset of faecal samples from each year were also characterised with two other primer pairs that amplify a region of the mtDNA 16S gene to allow species-level identification for most fish (16S_Fish) and krill (16S_Krill) species respectively. During amplification of markers, the products were tagged with a unique pair of index primers allowing samples to be pooled and sequenced (2x150bp) on a MiSeq high-throughput DNA sequencer. - See Adelie Pengiun Diet CCAMLR paper for all of the primer/PCR details - See BAS Adelie 18s Krill and Fish subset excel spreadsheet for sample details. - See BAS Adelie 18s ALL samples fastq for 18s fastq files - See BAS Adelie 16s Krill subset fastq for 16s krill fastq files - See BAS Adelie Fish subset fastq for 16s fish fastq files ##################################################################################### November 2018 In addition we also amplified all 450 samples with the 16S_Fish marker. - See Adelie Experiment Details 16s Fish for sample details, plate layout, first and second round PCR and miseq sheet. - See BAS Adelie Fish ALL Samples fastq for 16s fish fastq files

  • The foraging ecology of three fulmarine petrels including Cape petrels, Southern fulmars and Antarctic petrels were investigated at Hop Island during the 2015/16 austral summer. Two datasets were generated: 1) tracking data from Fulmarine petrels, and 2) stable isotope analysis of blood, feathers and egg shells. Tracking data were collected using Ecotone GPS trackers attached to the birds back feathers with tape. Location data has been interpolated using great circle distance to a time step of 15 minutes and include a record of whether the bird dived during that time period or not. Each location point was assigned a breeding stage (incubation or chick rearing) based on individual nest activities. Stable isotope ratios of carbon (13C/12C) and nitrogen (15N/14N) were determined by analysing 1 mg aliquots through continuous flow - elemental analysis - isotope ratio mass spectrometry (CF-EA-IRMS). Isotopic values of blood reflect approximately the last 52 days before sampling and thus the incubation period of all three species. Egg membranes and feathers remain metabolically inert after formation, and hence reflect the trophic niche during the pre-laying and moult period, respectively. We collected moult feathers during the chick-rearing period and therefore assumed that these were formed one year prior to the collection date and thus represent the trophic niche of the chick-rearing period one year earlier (austral summer 2014-15).

  • The demographic performance of high level antarctic predators is ultimately determined by the oceanic processes that influence the spatial and temporal distribution of primary productivity. This study will quantify the links between the foraging performance of southern elephant seals and a range of oceanographic parameters, including sea surface temperature, productivity and bathymetry. These data are a crucial component in understanding how antarctic predators will respond to changes in the distribution of marine and will be an important contribution to our understanding of the on-going decline in elephant seal numbers. Data were originally 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). However, these data have been replaced by an Access Database version, and have also been loaded into the Australian Antarctic Data Centre's ARGOS tracking database. The database can be accessed at the provided URLs.

  • GPS units were deployed on Adelie penguins at Hop Island in the Rauer Group during the 2011/12 field season. Deployments were made during the incubation, guard and creche periods. The units were later retrieved and the data downloaded. The data were collected following protocols approved by the Australian Antarctic Animal Ethics Committee and supported through the Australian Antarctic program through Australian Antarctic Science project 4087. The GPS units were supplied by Louise Emmerson of the Australian Antarctic Division through the AAS project 4087 budget and deployed and retrieved by Nobuo Kokubun of the National Institute of Polar Research, Japan with field assistance from Barbara Wienecke of the Australian Antarctic Division. Further information is available with the data. Please refer to the Seabird Conservation Team Data Sharing Policy for use, acknowledgement and availability of data prior to downloading data.

  • See spreadsheets - Gentoo Experiment Details 18s Each number corresponds to each worksheet 1. Samples and Date Gentoo penguin scats were collected from Cumberland Bay, South Georgia (from the Maiviken colony). Visits were made weekly between 3 April and 19 Sep 2018 (one visit in June was missed owing to avalanche risk). During each of the 24 visits, 25 fresh scats were collected, producing a total of 600 samples. Samples were scooped into a 2 ml plastic screw-top tube containing 80% ethanol with a clean spatula and frozen at -20 degrees. DNA was extracted from ~30 mg of faecal material using the Promega Maxwell RSC Tissue DNA Kit. Each extraction contained a soft part or ~500ml of EtOH slurry. The samples were spun down, the EtOH was poured off, the sample was re-suspended in 120ul of S.T.A.R buffer and homogenised. 100ul of the supernatant was added to well number 1 and samples were eluted in 100ul of TE. 2. Plate Layout Samples were diluted 1/10 and plated out on 96 well plates. Each plate had a positive control (fish, squid, shrimp DNA mix) and a negative PCR control. 3. 1st Round PCR. All samples were analysed using a highly conserved metazoan primer set that amplifies a region of the nuclear 18S gene ( McInnes et al. 2017a). The first round PCR is to amplify the target marker and add sample-specific (7bp) multiplex-identifier (MID) tags (forward and reverse primer) and Illumina sequencing primers. See sheet for PCR conditions. 4. 2nd Round PCR The second round PCR is to add sequencing adapters and additional 8 bp MIDs. See sheet for PCR conditions. 5. Miseq MiSeq genome sequencer (Illumina), using the MISEQ V2 reagent kits (300 cycles). See sheet for sample layout, i5 and i7 adapters and first round MID tags ########################################################################################### See spreadsheet - Gentoo Experiment Details Fish and Krill The scat samples containing prey DNA sequences from the 18S analysis (n=222) were characterised with two other primer pairs allow species-level identification for fish and krill. 1. Samples The samples positive for prey DNA and their plate layout 2. and 3. 1st Round PCR Krill /Degenerate The first round PCR is to amplify the target marker and add sample-specific (6bp) multiplex-identifier (MID) tags (forward and reverse primer) and Illumina sequencing primers. See sheet for PCR conditions. 4. 2nd Round PCR The second round PCR is to add sequencing adapters and additional 10 bp MIDs. See sheet for PCR conditions. 5. Miseq MiSeq genome sequencer (Illumina), using the MISEQ V2 reagent kits (300 cycles). See sheet for sample layout, R and F adapters and first round MID tags. This work was completed as part of AAS project 4556.

  • Metadata record for data from ASAC Project 419 See the link below for public details on this project. From the abstracts of some of the referenced papers: The population size and breeding success of Emperor Penguins (Aptenodytes forsteri) at the Auster and Taylor Glacier colonies were estimated during the 1988 breeding season. At Auster a total of 10963 pairs produced about 6350 fledglings for a breeding success of 58%. At Taylor Glacier about 2900 pairs raised 1774 fledglings for a breeding success of 61%. Fledglings left Taylor Glacier over a period of 33 days at a mean mass of 10.56kg. The accuracy of the tritiated water (HTO) and sodium-22 (22Na) turnover methods as estimators of dietary water and sodium intake was evaluated in emperor penguins fed separate diets of squid and fish. Emperor penguins assimilated 76.2% and 81.8% of available energy in the squid and fish diets, respectively. Both isotopes had equilibrated with body water and exchangeable sodium pools by 2h after intramuscular injection. The tritium method yielded reliable results after blood isotope levels had declined by 35%. On average the tritium method underestimated water intake by 2.9%, with a range of -10.3% to +11.1%. The 22Na method underestimated Na intake on average by 15.9% with the errors among individuals ranging from -37.2% to -1.8%. Discrepancies with 22Na turnover were significantly greater with the squid diet than the fish diet. The results confirm the reliability of the tritium method as an estimator of food consumption by free-living emperor penguins (provided seawater and freshwater ingestion is known) and support the adoption of the 22Na method to derive an approximation of seawater of seawater intake by tritiated emperor penguin chicks and by tritiated adults on foraging trips of short duration. The diet composition of Emperor Penguin Aptenodytes forsteri chicks was examined at Auster and Taylor Glacier colonies, near Australia's Mawson station, Antarctica, between hatching in mid-winter and fledging in mid-summer by 'water-offloading' adults. Chicks at both colonies were fed a similar suite of prey species. Crustaceans occurred in 82% of stomach samples at Auster and 87% of stomachs at Taylor Glacier and were heavily digested; their contribution to food mass could not be quantified. Fish, primarily bentho-pelagic species, accounted for 52% by number and 55% by mass of chick diet at Auster, and squid formed the remainder. At Taylor Glacier the corresponding values were 27% by number and 31% by mass of fish and 73% by number and 69% by mass of squid. of the 33 species or taxa identified, the fish Trematous eulepidotus and the squid Psychroteuthis glacialis and Alluroteuthis antarcticus accounted for 64% and 74% of the diets by mass at Auster and Taylor Glacier, res pectively. The sizes of fish varied temporally but not in a linear manner from winter to summer. Adult penguins captured fish ranging in length from 60 mm (Pleuragramma antarcticum) to 250 mm (T. eulepidotus) and squid (P. glacialis) from 19 to 280 mm in mantle length. The length-frequency distribution of P. glacialis showed seasonal variation, with the size of squid increasing from winter to summer. The energy density of chick diet mix increased significantly prior to 'fledging'.

  • At Hop Island in the Rauer Group during the 2012/13 field season combinations of data loggers were deployed on different adelie penguins. The data loggers were GPS (two types), time-depth recorders and accelerometers. The accelerometer records head movement to identify when the bird captures prey. The units were later retrieved and the data downloaded. A document included with the data has further information about the data. The data were collected following protocols approved by the Australian Antarctic Animal Ethics Committee and supported through the Australian Antarctic program through Australian Antarctic Science project 4087. Data from GPS units deployed at Hop Island in 2011/12 is described by the metadata record with ID AAS_4087_adelie_penguin_tracking_hop_island_2011_12.