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  • This video is supplementary data for the publication entitled 'Internal physiology of live krill revealed using new aquaria techniques and mixed optical microscopy and optical coherence tomography (OCT) imaging techniques'. The video is high resolution microscopy video of a live krill captured in the krill containment trap placed within the water bath. File size: 1.8 GB, 32 s duration. The optical microscopy was carried out using a Leica M205C dissecting stereomicroscope with a Leica DFC 450 camera and Leica LAS V4.0 software to collect high-resolution video. The experimental krill research project is designed to focus on obtaining life history information of use in managing the krill fishery - the largest Antarctic fishery. In particular, the project will concentrate on studies into impacts of climate change on key aspects of krill biology and ecology.

  • This is a local copy of a metadata record and dataset stored at Dryad. This local copy is maintained in order to provide a link to the originating Australian Antarctic program project. See the link to the Dryad site at the provided URL for full details on this data set. Age is a fundamental aspect of animal ecology, but is difficult to determine in many species. Humpback whales exemplify this as they have a lifespan comparable to humans, mature sexually as early as four years and have no reliable visual age indicators after their first year. Current methods for estimating humpback age cannot be applied to all individuals and populations. Assays for human age have recently been developed recently based on age-induced changes in DNA methylation of specific genes. We used information on age-associated DNA methylation in human and mouse genes to identify homologous gene regions in humpbacks. Humpback skin samples were obtained from individuals with a known year of birth and employed to calibrate relationships between cytosine methylation and age. Seven of 37 cytosines assayed for methylation level in humpback skin had significant age-related profiles. The three most age-informative cytosine markers were selected for a humpback epigenetic age assay. The assay has an R2 of 0.787 (p = 3.04e-16) and predicts age from skin samples with a standard deviation of 2.991 years. The epigenetic method correctly determined which of parent-offspring pairs is the parent in more than 93% of cases. To demonstrate the potential of this technique, we constructed the first modern age profile of humpback whales off eastern Australia and compared the results to population structure five decades earlier. This is the first epigenetic age estimation method for a wild animal species and the approach we took for developing it can be applied to many other non model organisms.

  • Spectra: one binary file per spectrum. Spectra can be processed using DOASIS or QDOAS software. Spectrum files are saved in folders numbered by date. Daily log files: for spectra (extra geometric information as well as latitude, longitude, solar zenith angle) and temperature (instrument, internal and external temperature measurements). Accelerometer: One ascii file per day with pitch, roll and yaw euler angles as the columns Images: taken by a small camera, co-directional with the MAX-DOAS, for context of broad light conditions (i.e. checking sunny/cloudy weather) Calibration files: Binary and text files for dark current, offset, slit function shape and wavelength calibrations

  • The embryonic development of Antarctic krill (Euphausia superba) is sensitive to elevated seawater CO2 levels. This data set provides the experimental data and WinBUGS code used to estimate hatch rates under experimental CO2 manipulation, as described by Kawaguchi et al. (2013). Kawaguchi S, Ishida A, King R, Raymond B, Waller N, Constable A, Nicol S, Wakita M, Ishimatsu A (2013) Risk maps for Antarctic krill under projected Southern Ocean acidification. Nature Climate Change (in press) Circumpolar pCO2 projection. To estimate oceanic pCO2 under the future CO2 elevated condition, we computed oceanic pCO2 using a three-dimensional ocean carbon cycle model developed for the Ocean Carbon-Cycle Model Intercomparison Project (2,3) and the projected atmospheric CO2 concentrations. The model used, referred to as the Institute for Global Change Research model in the Ocean Carbon-Cycle Model Intercomparison Project, was developed on the basis of that used in ref. 4 for the study of vertical fluxes of particulate organic matter and calcite. It is an offline carbon cycle model using physical variables such as advection and diffusion that are given by the general circulation model. The model was forced by the following four atmospheric CO2 emission scenarios and their extensions to year 2300. RCP8.5: high emission without any specific climate mitigation target; RCP6.0: medium-high emission; RCP 4.5: medium-low emission; and RCP 3.0-PD: low emission (1). Simulated perturbations in dissolved inorganic carbon relative to 1994 (the Global Ocean Data Analysis Project (GLODAP) reference year) were added to the modern dissolved inorganic carbon data in the GLODAP dataset (5). To estimate oceanic pCO2, temperature and salinity from the World Ocean Atlas data set (6) and alkalinity from the GLODAP data set were assumed to be constant. Marine ecosystems of the Southern Ocean are particularly vulnerable to ocean acidification. Antarctic krill (Euphausia superba; hereafter krill) is the key pelagic species of the region and its largest fishery resource. There is therefore concern about the combined effects of climate change, ocean acidification and an expanding fishery on krill and ultimately, their dependent predators—whales, seals and penguins. However, little is known about the sensitivity of krill to ocean acidification. Juvenile and adult krill are already exposed to variable seawater carbonate chemistry because they occupy a range of habitats and migrate both vertically and horizontally on a daily and seasonal basis. Moreover, krill eggs sink from the surface to hatch at 700–1,000m, where the carbon dioxide partial pressure (pCO2 ) in sea water is already greater than it is in the atmosphere. Krill eggs sink passively and so cannot avoid these conditions. Here we describe the sensitivity of krill egg hatch rates to increased CO2, and present a circumpolar risk map of krill hatching success under projected pCO2 levels. We find that important krill habitats of the Weddell Sea and the Haakon VII Sea to the east are likely to become high-risk areas for krill recruitment within a century. Furthermore, unless CO2 emissions are mitigated, the Southern Ocean krill population could collapse by 2300 with dire consequences for the entire ecosystem. The risk_maps folder contains the modelled risk maps for each of the climate change scenarios (i.e. Figure 4 in the main paper, and Figure S2 in the supplementary information). These are in ESRI gridded ASCII format, on a longitude-latitude grid with 1-degree resolution. Refs: 1. Meinshausen, M. et al. The RCP greenhouse gas concentrations and their extensions from 1765 to 2300. Climatic Change 109, 213-241 (2011). 2. Orr, J. C. et al. Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms. Nature 437, 681-686 (2005). 3. Cao, L. et al. The role of ocean transport in the uptake of anthropogenic CO2. Biogeosciences 6, 375-390 (2009). 4. Yamanaka, Y. and Tajika, E. The role of the vertical fluxes of particulate organic matter and calcite in the oceanic carbon cycle: Studies using an ocean biogeochemical general circulation model. Glob. Biogeochem. Cycles 10, 361-382 (1996). 5. Key, R. M. et al. A global ocean carbon climatology: Results from Global Data Analysis Project (GLODAP). Glob. Biogeochem. Cycles 18, GB4031 (2004). 6. Conkright, M. E. et al. World Ocean Atlas 2001: Objective Analyses, Data Statistics, and Figures CD-ROM Documentation (National Oceanographic Data Center, 2002).

  • Metadata record for data from ASAC Project 2897 See the link below for public details on this project. Public The aim of this multi-disciplinary proposal is to examine the molecular evolution of toxic proteins across the full taxonomical spectrum of venomous Antarctic marine animals. The project will create a comparative encyclopedia of the evolution of the venom system in the Antarctic marine animal kingdom and elucidate the underlying structure-function relationships between these toxic proteins. Through a process utilising cutting edge analytical techniques, such as cDNA cloning and molecular modelling, a feedback loop of bioactivity testing will be created to contribute substantially towards the area of drug design and development from toxic animal peptides. Project objectives: The aim of this project is to investigate the evolution of the molecular, structural and functional properties of Antarctic marine animal venom systems. This integrative project aims to investigate the origin and evolution of secreted proteins in the venom glands of toxic polar animals by means of: - Analysis of mechanisms of evolution in multigene families. - Phylogenetic analysis of evolutionary relationships among secreted proteins in the venom glands of major lineages; - Search for correlations between: (i) evolution of venom gland structure (ii) molecular evolution of venom components, and (iii) ecological specialisation of the animal - Bioactivity studies will be conducted upon representative purified or synthesised proteins. - A first ever comparison of the convergent strategies between Arctic and Antarctic endemic fauna. The results will help us to understand protein evolution, will cast light on the classic problem of how venom systems evolve, and may provide leads in the search for commercially-exploitable venom proteins. Taken from the 2008-2009 Progress Report: Progress against objectives: We have completed the genetic analyses of the specimens and sequence analyses. Phylogenetic positioning is robust other than a few deep level nodes. We are undertaking a second round of genetic analyses using different primers in order to resolve these nodes. Biochemical analyses of crude protein secretions from the posterior salivary (venom) glands has revealed temperature specific modifications of some of the venom components to adapt them to the polar conditions. We have tested the secretions in a battery of assays. We are now repeating those assays using purified proteins in order to determine which types are responsible for particular effects and also investigate synergistic interactions. Taken from the 2009-2010 Progress Report: Progress against objectives: We have undertaken genetic analyses of the specimens collected, and investigated specific adaptations of their venom systems. Results to-date include: - Antarctic octopuses are more genetically diverse than previously appreciated, including at least one new genus - an inverse relationship exists between the size of the venom gland and the size of the beak - their venoms have undergone temperature-specific adaptations

  • Aerial surveys of southern right whales (Eubalaena australis) were undertaken off the southern Australian coast to monitor the recovery of this endangered species following extreme 19th and 20th Century commercial whaling. The aerial survey was undertaken in the coastal waters from Perth (Western Australia) to Ceduna (South Australia) between the 12th and 17th August 2021, to maintain the annual series of surveys and inform the long-term population trend. The maximum whale counts for each leg of the survey flights between Cape Leeuwin and Ceduna, and consisted of a total 643 southern right whales sighted across the survey area (270 cow-calf pairs and 103 unaccompanied whales). The subsequent population estimate for the Australian ‘south-western’ population is 2,549 whales, which represents the majority of the Australian population given the very low numbers in the ‘south-eastern’ subpopulation. The population long-term trend data is indicating recent years (from 2007) are showing greater inter-annual variation in whale counts. To evaluate the recovery of the southern right whale population, it will be critical to collect long-term data on the annual variability in whale numbers related to the non-annual female breeding cycle and identify possible impacts on this by short-term climate dynamics, longer-term climate change and/or anthropogenic threats.

  • This dataset contains acoustic recordings from Directional Frequency Analysis and Recording (DIFAR) sonobuoys that were deployed throughout the 2012 Blue Whale Voyages conducted off Portland, Victoria, Australia from January – March (in the Bonney Upwelling). During the 20 days at sea 131 AN/SSQ-53D sonobuoys were deployed yielding more than 500 hours of acoustic recordings. In January a total team of three dedicated acousticians monitored round-the-clock for blue whales and in all weather conditions. In March the team size was increased so that five acousticians monitored and tracked blue whales round-the-clock. The recording chain for all sonobuoy deployments through 25 March 2012 included a 3-dB communications antenna with a central frequency at 161 MHz and masthead amplifier connected to a passive four way splitter. The highest point of the antenna was approximately 14 m above sea level. The antenna, amplifier, and splitter were connected with low loss cable, and each output of the four way splitter connected to the DIFAR input of a WiNRaDiO 2902i sonobuoy VHF receiver. On 25 March the masthead amplifier failed and was removed from the recording chain. This failure prompted the use of recently acquired WiNRaDiO G39WSBe sonobuoy receivers. The A/D converter used throughout both voyages was a RME Fireface UFX. The voltage outputs of all of the sonobuoy receivers were calibrated as a function of modulation frequency before the voyage, and DIFAR outputs from each of the 2902i and G39WSBe were connected to an instrument input of the UFX. The instrument inputs of the UFX (analog inputs 9-12) have a peak-peak voltage range of 80 V with digitally controlled gain that can be set between 10-65 dB, and this setting was noted in the Sonobuoy Deployment Log (see below) in order to measure received sound-pressure levels accurately. The digitised signals from the UFX were saved as 16-bit WAV files with 48 kHz sample rate using passive acoustic monitoring software Pamguard. Directional calibration The magnetic compass in each sonobuoy was calibrated/validated upon deployment as described by Miller et al. (2015, 2016). Calibration procedure involved measuring the mean bearing error and standard deviation of errors between the GPS-derived bearing from the sonobuoy to the ship and the magnetic bearing to the ship noise detected by the sonobuoy. 15-30 bearings were used for each calibration as the ship steamed directly away from the deployment location. Intensity calibration Obtaining calibrated intensity measurements from sonobuoys not only requires knowledge of the sensitivity of the hydrophone, but also the calibration parameters of the radio transmitter and radio receiver. Throughout the voyage, a hydrophone sensitivity of -122 dB re 1 V/µPa was applied to recordings via the Hydrophone Array Manager in PAMGuard. This value is defined in the DIFAR specification as the reference intensity at 100 Hz that will generate a frequency deviation of 25 kHz (Maranda 2001), thus the specification combines the hydrophone sensitivity and transmitter calibration. In line with manufacturers specifications, the WiNRADiO G39 WSB and 2902i both had a measured voltage response of approximately 1 V-peak–peak (approximately -3 dB) at 25 kHz frequency deviation (Miller et al. 2014), and this can be subtracted from the hydrophone sensitivity to yield an total combined factor of 125 dB re 1 V/µPa. These calibration settings, along with the shaped filter response provided by Greene et al. (2004) make it possible to obtain calibrated pressure amplitude from the recorded WAV audio files. Sonobuoy deployment metadata (Sonobuoy deployment log) This spreadsheet contains metadata on the deployment of sonobuoys deployed during the 2013 Antarctic Blue Whale Voyage. The first row contains column headers, while each subsequent row contains deployment information for a single sonobuoy. Information contained in each column are: buoyID: Buoy ID number is the sequential number of the buoy starting at 1 for the first buoy of the trip. startDate: Date (UTC) at the start of the sonobuoy deployment (YYYY-MM-DD) startTime: Time (UTC) at the start of the sonobuoy deployment (HH:MM:SS) 2 digit hour with 24 hour clock and leading zero. stopDate: Date (UTC) at the end of the sonobuoy deployment (YYYY-MM-DD). While the recording is in progress this should be 1,2 4 or 8 hours after the startTime based on sonobuoy setting. stopTime: Time (UTC) at the end of the sonobuoy deployment (HH:MM:SS). While the recording is in progress this should be 1,2 4 or 8 hours after the startTime based on the sonobuoy setting. lat: Latitude of deployment in decimal degrees. Southern hemisphere latitudes should be negative. long: Longitude of deployment in decimal degrees. Western hemisphere longitudes should be negative. alt: Depth of the sonobuoy deployment in metres. For DIFAR sonobuoys either 30, 120 or 300. recordingChannel: This is the channel number within the recorded wav-file that contains audio from this buoy as would be reported by Matlab. Channel numbers start at 1 (1-indexed) so usually this will be 1, 2 or 3. magVariation: The magnetic variation in degrees. Positive declination is East, negative is West. At the start of a recording this will be entered from a chart. As the recording progresses, this should be updated by measuring the bearing to the vessel. sonobuoyType: The an/ssq designation for the sonobuoy. Usually 53B, 53D, 53F, HIDAR, 57A/B, or 36Q. receiver: The type and serial number of the calibrated radio receiver (WinRadio) used to receive the VHF signal. (wr15725, wr17274, wr15274, or wr15273) preamp: The (unitless) gain in dB of any preamplifier (including the instrument preamp from the Fireface UFX). Usually 10 or 20 dB. adc: The analog-to-digital converter (adc) used to digitize the audio. This is the sound card name and gain. All data were recorded on an RME Fireface UFX, so Ufx10 would be the RME Fireface UFX with a gain of 10 dB. vhfFreq: The VHF channel number used to receive the sonobuoys. Sonobuoys have 99 pre-set VHF channels between Real-time monitoring and analysis (Acoustic event log) During the 2012 Blue Whale Voyages Acousticians noted all whale calls and other acoustic events that were detected during real-time monitoring in a written Sonobuoy Event Log. Additionally, the acoustic tracking software, difarBSM, stored processed bearings from acoustic events and cross bearings in tab delimited text files. Each event was assigned a classification by the acoustician, and events for each classification were stored in separate text files. The first row in each file contains the column headers, and the content of each column is as follows: buoyID: Buoy ID number is the number of the sonobuoy on which this event was detected. This can be used as a foreign key to link to the sonobuoy deployment log. timeStamp_matlabDatenum: Date and time (UTC) at the start of the event represented as a Matlab datenum (i.e. number of days since Jan 0 0000). Latitude: Latitude of the sonobuoy deployment in decimal degrees. Southern hemisphere latitudes should be negative. Longitude: Longitude of sonobuoy deployment in decimal degrees. Western hemisphere longitudes should be negative. Altitude: Depth of the sonobuoy deployment in metres. For DIFAR sonobuoys either 30, 120 or 300. magneticVariation_degrees: The estimated magnetic variation of the sonobuoy in degrees at the time of the event. Positive declination is East, negative is West. At the start of a recording this will be entered from a chart. As the recording progresses, this should be updated by measuring the bearing to the vessel. bearing_degreesMagnetic: Magnetic bearing in degrees from the sonobuoy to the acoustic event. Magnetic bearings were selected by the acoustician by choosing a single point on the bearing-frequency surface (AKA DIFARGram) produced by the analysis software difarBSM. frequency_Hz: The frequency in Hz of the magnetic bearing that the acoustician selected from the bearing-frequency surface (DIFARGram). logDifarPower: The base 10 logarithm of the height of the point on the DIFARGram receiveLevel_dB: This column contains an estimate of the The RMS receive level (dB SPL re 1 micro Pa) of the event. Received levels were estimated by applying a correction for the shaped sonobuoy frequency response, the receiver’s frequency response, and were calculated over only the frequency band specified in each classification (see below). soundType: soundType is the classification assigned to the event by the acoustician. Aural and visual monitoring of audio and spectrograms from each sonobuoy was conducted for each sonobuoy deployment. Detections from marine mammals, and other sources and were detected and classified manually, and their time and frequency bounds were marked on the PAMGuard spectrogram. Parameters for monitoring and recording, were stored within the PAMGuard database and as stand-alone Pamguard Settings Files (PSF). During the voyage there were detections of pygmy blue whale song, and blue whale 'D-call' vocalisations. During the dedicated blue whale voyages the course of the ship was diverted to follow bearings to vocalising blue whales. Whale tracking log (Written Whale Acoustic Tracking Log - Tangaroa 2015.pdf) During the 2012 Blue Whale Voyages, noted all whale calls and other acoustic events that were detected during real-time monitoring in a Sonobuoy Event Log. A written summary of the event log was recorded during data collection at approximately 15 minute intervals, and this summary comprises the Whale Tracking Log. - Tracking Log. - Entries in the written Sonobuoy Tracking Log (on the bench in the acoustics workstation) also include total number of different whales heard in that 15 minute interval. - If multiple whales/groups were detected, then the acoustician on-duty, in consultation with the lead acoustician and/or voyage management designateded one of the whales the 'target' whale, and attempted to encounter this target first. - When targeting a whale/group, the acoustician on-duty continued to track all other whales/groups in the area as these tracked whales/groups may become the next target after obtaining concluding with the current target. Date: (UTC) written only at top of datasheet Time: (UTC) on the hour, 15 past, half past, and 15 to. Track: Unique identifier for each whale/group tracked in the past 15 minutes. Each track will have: Position: Either an average bearing from a sonobuoy (eg 220 degrees from SB18) or a Lat/Lon from the most recent triangulation Notes: What is the vessel action with respect to this tracked whale/group? (eg. Is this the current or previous 'target'? Are we presently photographing this whale? Did we finish photographing the whale?) Has the whale gone silent? Has this track crossed paths with another?

  • These aerial survey data of southern right whales (Eubalaena australis) off southern Australia were collected in August 2017. Such annual flights in winter/spring between Cape Leeuwin (Western Australia) and Ceduna (South Australia) have now been conducted over a 25-year period 1993-2017. These surveys have provided evidence of a population trend of around 6% per year, and a current (at 2014) population size of approximately 2300 of what has been regarded as the 'western' Australian right whale subpopulation. With estimated population size in the low thousands, it is presumed to be still well below carrying capacity. No trend information is available for the 'eastern' subpopulation of animals occurring around the remainder of the southern Australian Coast, to at least as far as Sydney, New South Wales and the populations size is relatively small, probably in the low hundreds. A lower than expected 'western' count in 2015 gives weak evidence that the growth rate may be starting to show signs of slowing, though an exponential increase remains the best description of the data. If the low 2015 count is anomalous, future counts may be expected to show an exponential increase, but if it is not, modelling growth as other than simple exponential may be useful to explore in future

  • Annual aerial surveys of southern right whales have been conducted off the southern Australian coast, between Cape Leeuwin (W.A.) and Ceduna (S.A.) over a 28 year period between 1993 and 2020, to monitor the recovery of this species following commercial whaling. We conducted an aerial survey of southern right whales between the 20th and 24th August 2020, to continue these annual series of surveys and inform the long-term population trend. The comparable count for the 2020 survey utilised the maximum count for each leg and incorporated a correction for the unsurveyed area between Head of the Bight to Ceduna due to the inability to cover whole survey as a result of COVID-19 restrictions between State borders. This resulted in 384 individuals, consisting of 156 cows accompanied by calves of the year and 72 unaccompanied adults. Of these, 126 images of individual whales have been selected for photo-identification matching. This is a significant decrease in overall sightings that has not been observed for over 13 years when compared to long term trend data for the population; last seen in 2007 (N = 286 individuals). The subsequent population estimate for the Australian ‘western’ subpopulation is 2,585 whales, which is also a significant decrease in estimated population size from 3,164 in 2019 to 2,585 in 2020. The extremely low number of unaccompanied adults (N = 68) had the greatest impact on the overall number of sightings in 2020, and is the lowest number sighted since 1993 (N = 47). Previous surveys in 2007 and 2015 have been noted as years of low whale counts that had been deemed anomalous years, although the low numbers from this survey questions this and may suggest the 3-year female breeding cycle is becoming more unpredictable. Considerable inter-annual variation in whale numbers, and cycles in population growth, makes it difficult to detect consistent and reliable changes in abundance from one year to the next, or even over longer periods of time. This severely inhibits our ability to identify immediate threats to the population and strongly supports continued annual population surveys.

  • These aerial survey data of southern right whales (Eubalaena australis) off southern Australia were collected in August 2018. Such annual flights in winter/spring between Cape Leeuwin (Western Australia) and Ceduna (South Australia) have now been conducted over a 26-year period 1993-2018. These surveys have provided evidence of a population trend of around 6% per year, and a current (at 2014) population size of approximately 2300 of what has been regarded as the 'western' Australian right whale subpopulation. With estimated population size in the low thousands, it is presumed to be still well below carrying capacity. No trend information is available for the 'eastern' subpopulation of animals occurring around the remainder of the southern Australian Coast, to at least as far as Sydney, New South Wales and the populations size is relatively small, probably in the low hundreds. A lower than expected 'western' count in 2015 gives weak evidence that the growth rate may be starting to show signs of slowing, though an exponential increase remains the best description of the data. If the low 2015 count is anomalous, future counts may be expected to show an exponential increase, but if it is not, modelling growth as other than simple exponential may be useful to explore in future.