SEALS
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Seal colonies on Macquarie Island. This is a polygon dataset stored in the Geographical Information System (GIS). Attributes include the species name and whether breeding occurs within the area represented. The species include Southern Elephant and Fur.
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Elephant seals use a suite of physiological and behavioural mechanisms to maximise the time they can be submerged. Of these hypo-metabolism is one of the most important, so this study quantified maximum O2 consumptions relative to dove depth and swim speed. From the abstract of the referenced paper: Heart rate, swimming speed, and diving behaviour were recorded simultaneously for an adult female southern elephant seal during her postbreeding period at sea with a Wildlife Computers heart-rate time depth recorder and a velocity time depth recorder. The errors associated with data storage versus real-time data collection of these data were analysed and indicated that for events of short duration (i.e., less than 10 min or 20 sampling intervals) serious biases occur. A simple model for estimating oxygen consumption based on the estimated oxygen stores of the seal and the assumption that most, if not all, dives were aerobic produced a mean diving metabolic rate of 3.64 mL O2 kg-1, which is only 47% of the field metabolic rate estimated from allometric models. Mechanisms for reducing oxygen consumption while diving include cardiac adjustments, indicated by reductions in heart rate on all dives, and the maintenance of swimming speed at near the minimum cost of transport for most of the submerged time. Heart rate during diving was below the resting heart rate while ashore in all dives, and there was a negative relationship between the duration of a dive and the mean heart rate during that dive for dives longer than 13 min. Mean heart rates declined from 40 beats min-1 for dives of 13 min to 14 beats min-1 for dives of 37 min. Mean swimming speed per dive was 2.1 m s-1, but this also varied with dive duration. There were slight but significant increases in mean swimming speeds with increasing dive depth and duration. Both ascent and descent speeds were also higher on longer dives. 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 provided URL). Data for this project is the same data that was collected for ASAC projects 769 and 589 (ASAC_769 and ASAC_589).
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Elephant seals use a suite of physiological and behavioural mechanisms to maximise the time they can be submerged. Of these hypo-metabolism is one of the most important, so this study quantified maximum O2 consumptions relative to dove depth and swim speed. From the abstract of the referenced paper: The ability of air-breathing marine predators to forage successfully depends on their ability to remain submerged. This is in turn related to their total O2 stores and the rate at which these stores are used up while submerged. Body size was positively related to dive duration in a sample of 34 adult female southern elephant seals from Macquarie Island. However, there was no relationship between body size and dive depth. This indicates that smaller seals, with smaller total O2 stores, make shorter dives than larger individuals but operate at similar depths, resulting in less time being spent at depth. Nine adult female elephant seals were also equipped with velocity time depth recorders. In eight of these seals, a plot of swimming speed against dive duration revealed a cloud of points with a clear upper boundary. This boundary could be described using regression analysis and gave a significant negative relationship in most cases. These results indicate that metabolic rate varies with activity levels, as indicated by swimming speed, and that there are quantifiable limits to the distance that a seal can travel on a dive of a given swimming speed. However, the seals rarely dive to these physiological limits, and the majority of their dives are well within their aerobic capacity. Elephant seals therefore appear to dive in a way that ensures that they have a reserve of O2 available. 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). Data for this project is the same data that was collected for ASAC projects 857 and 589 (ASAC_857 and ASAC_589).
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The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research (SCAR) 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. The RAATD project team consolidated tracking data for multiple species of Antarctic meso- and top-predators to identify Areas of Ecological Significance. These datasets constitute the compiled tracking data from a large number of research groups that have worked in the Antarctic since the 1990s. This metadata record pertains to the "standardized" version of the data files. These files contain position estimates as provided by the original data collectors (generally, raw Argos or GPS locations, or estimated GLS locations). Original data files have been converted to a common format and quality-checking applied, but have not been further filtered or interpolated. Periods at the start or end of deployments were identified and discarded if there was evidence that location data during these periods did not represent the animals' at-sea movement. For example, tags may have been turned on early (thereby recording locations prior to their deployment on animals) or animals may have remained at the deployment site, e.g. the breeding colony, for an extended period at the start or end of the tag deployment. Some tracks also showed a marked deterioration in the frequency and quality (for PTTs) of location estimates near the end of a track. Such locations were visually identified based on maps of each track in conjunction with plots of location distance from deployment site against time. This information is captured in the location_to_keep column appended to each species’ data file (1 = keep, 0 = discard). The code used to trim the tracks can be found in the https://github.com/SCAR/RAATD repository. This data set comprises one metadata csv file that describes all deployments, along with data csv files (17 files, one per species) containing the position data. For details of the file formats, consult the data paper. The data are also available in a filtered version (see https://data.aad.gov.au/metadata/records/SCAR_EGBAMM_RAATD_2018) that have been processed using a state-space model in order to estimate locations at regular time intervals.
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The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research (SCAR) 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. The RAATD project team consolidated tracking data for multiple species of Antarctic meso- and top-predators to identify Areas of Ecological Significance. These datasets constitute the compiled tracking data from a large number of research groups that have worked in the Antarctic since the 1990s. This metadata record pertains to the "filtered" version of the data files. These files contain position estimates that have been processed using a state-space model in order to estimate locations at regular time intervals. For technical details of the filtering process, consult the data paper. The filtering code can be found in the https://github.com/SCAR/RAATD repository. This data set comprises one metadata csv file that describes all deployments, along with data files (3 files for each of 17 species). For each species there is: - an RDS file that contains the fitted filter model object and model predictions (this file is RDS format that can be read by the R statistical software package) - a PDF file that shows the quality control results for each individual model - a CSV file containing the interpolated position estimates For details of the file contents and formats, consult the data paper. The data are also available in a standardized version (see https://data.aad.gov.au/metadata/records/SCAR_EGBAMM_RAATD_2018_Standardised) that contain position estimates as provided by the original data collectors (generally, raw Argos or GPS locations, or estimated GLS locations) without state-space filtering.
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Introduction: During the seasons of 1954-1956 samples of liver and blood were collected from animals at Heard Island and Antarctica by members of the Australian Antarctic Expeditions. These samples were obtained primarily for determination of copper levels (see reference). Iron determinations were made concurrently by Beck and histological examinations were made on some of the liver samples by the late Dr H.W. Bennetts, at that time the Veterniary Pathologist of the Department of Agriculture. The data were not extensive enough for publication, but they are presented here for the information of other workers. Experimental: Blood was collected as it flowed from the bullet-hole after shooting. Samples were collected in bottles containing purified potassium oxalate and were subsequently preserved with purified thymol. Liver samples for analyses were preserved in a purified ethanol-formalin mixture. Those for histological studies were stored in buffered formal-saline. No special precautions were taken to remove all blood from the liver samples. Iron was estimated by the thioglycollic acid method of Mayer and Bradshaw (Analyst, 1951, 76, 715) after oxidation of organic matter with nitric, sulphuric and perchloric acids. Blood iron results are expressed as micrograms Fe per ml. If seal and penguin haemoglobin is similar to that of terrestrial species, 680 micrograms Fe per ml will equal about 20g haemoglobin per 100 ml blood. Liver results are expressed as parts per million Fe on dry matter. No correction was made for fat content as all samples (except for one leopard seal) were low in fat. The sample from the leopard seal contained 28% fat and the iron content has been calculated to a fat free basis. As it was possible that the high levels of iron are related to the diving habits of the seals, iron determinations were also made on livers from whales taken along the Australian coast. Some blood and liver iron levels for terrestrial species and for the Australian salmon are included for comparison. Results and Discussion: Detailed results for the seals and penguins and other animals are available at the url below. The levels of iron in the seal blood samples are extremely high and similar observations have been made by numerous other workers. The levels in Weddell seals Nos. 18 and 20 contain the equivalent of 30-35g haemoglobin per 100 ml blood. This level may be compared with 10-15g per 100 ml of terrestrial species. The levels of iron in the livers of the Weddell seals and in the penguins is generally higher than the corresponding values in terrestrial species. The values for elephant seals are however consistently higher than all other species. Several possible reasons can be advanced for the high iron content of the livers from elephant seals. 1) Contamination by blood is undoubtedly a factor. This is born out by the histological report of congestion of the sinusoids. Dr Budd, in a personal letter on April 17 1955, comments on the rather extraordinary slowness with which blood drains from seal liver. The fact that the very high liver iron levels are associated with heavy haemosiderin deposits indicates that blood contamination is only part of the reason for the high iron levels. 2) A small amount of contamination by black sand occurred in some of the Heard Island livers. We obtained a sample of this black sand but it contained only 3.3% soluble Fe. If there were 1% sand in the samples it would only increase the liver Fe by 330 ppm. As the sand contamination was far less than 1% I do not consider that it has contributed significantly to the liver iron values. 3) The haemosiderin may possibly be due to some virus or organism which caused blood breakdown. However, there was no comment of any sign of disease by those who collected the samples. Dr L.G.C.E. Pugh (Nature, Jan 10th 1959, 183, 74) comments on the ease of hydrolysis of Weddell seal blood and considers that the cell fragility may contribute to the high rate of destruction of red cells. If a very high destruction rate occurs in the blood of elephant seals this could account for the liver haemosiderin. 4) The high liver haemosiderin may merely be a normal iron reserve for what must be a very high iron requirement for blood production in this species. On the other hand the Weddell seals have just as high haemoglobin levels and yet the iron levels in the liver are much lower. The fields in this dataset are: antarctic blood duck fowl haemoglobin iron liver penguins petrels rabbit seals sheep skuas subantarctic whales animal No. common name scientific name taxon id locality date details blood Fe (ug/ml) liver Fe (p.p.m. on dry liver) Haemo-siderin in liver comments specials No. of samples iron content blood (micro grams per ml) iron content liver (ppm on dry matter)
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APIS data were collected between 1994 and 1999. This dataset also includes some historical data collected between 1985 and 1987. Both aerial and ship-board surveys were conducted. Studies on the behaviour of Pack-ice or Crabeater Seal (Lobodon carcinophagus) in the Southern Ocean and in the Australian Sector of Antarctica were also conducted as part of this study. Satellite tracking was used to determine their movement, durations on land and at sea, dive depths and dive duration etc. The four species of Antarctic pack ice seals (crabeater, leopard, Weddell, and Ross seals) are thought to comprise up to 50% or more of the world's total biomass of seals. As long-lived, top level predators in Southern Ocean ecosystems, pack ice seals are scientifically interesting because they can assist in monitoring shifts in ecosystem structure and function, especially changes that occur in sensitive polar areas in response to global climate changes. The APIS Program focuses on the ecological importance of pack ice seals and their interactions with physical and biotic features of their environment. This program is a collaborative, multi-disciplinary research initiative whose planning and implementation has involved scientists from more than a dozen countries. It is being developed and coordinated by the Group of Specialists on Seals of the Scientific Committee on Antarctic Research (SCAR), and represents an important contribution to SCAR's Antarctic Global Change Program. Australian researchers have undertaken an ambitious science program studying the distribution and abundance of pack ice seals in support of the APIS Program. An excellent overview of this work is provided at the Australian Antarctic Division's web site. The following paragraphs provide a brief progress report of some of that work through 1998. ------------------------------------------------------------------------------- Four years of developmental work have now been completed in preparation for the Australian contribution to the circumpolar survey that will take place in December 1998. Until recently the main effort has been directed towards designing and building a system for automatic data logging of line transect data by double observers. Two systems identical in concept have been designed for aerial survey and shipboard survey. The systems consist of a number of sighting guns and keypads linked to a central computer. The sightings guns are used to measure the exact time and angle of declination from the horizon of seals passing abeam of the survey platform. Also logged regularly (10 second intervals) are GPS position and altitude (aerial survey only). The aerial survey system also has an audio backup. The aerial survey system has been trialled over three seasons and the shipboard system over one season. Preliminary analysis of aerial data indicates that the essential assumption of the line transect method is badly violated, reinforcing the need for double observers. Assumption violation is likely to be less in shipboard survey, but assessment of the assumption of perfect sightability on the line is still important. User manuals have been written for both the aerial and shipboard systems. An aerial survey system is being constructed for use by BAS in the coming season. A backup manual system for aerial and shipboard survey has also been developed in the event of the automatic system failing. The aerial backup system uses the perspex sighting frame developed by the US. A database has been designed for storage and analysis of aerial and shipboard data. Importing of data is fast and easy, allowing post-survey analysis and review immediately after each day's survey effort. Aides for training observers have been developed. A video on species identification has been produced. A Powerpoint slide show has been designed to simulate aerial survey conditions and use of the automatic data logging system. Currently effort has been directed toward developing an optimal survey design. While a general survey plan is necessary, it must be flexible to deal with unpredictable ice and weather conditions. It is planned to use both the ship and two Sikorsky 76 helicopters as survey platforms. The ship will be used to survey into and out from stations, and inwards from the ice edge for approximately 60 miles. The helicopters will be used to survey southwards from the ship for distances up to 140 miles in favourable weather. Helicopters will fly in tandem, with transects 10 miles apart. Studies of crabeater seal haul-out behaviour have been conducted over the past four seasons. Twenty SLTDRs have been deployed in the breeding season (September-October). The length of deployments varies from a few days to 3 months. No transmissions have been received after mid-January, probably due to loss of instruments during the moult. Most instruments have transmitted data through the survey period of November-December. Haul-out behaviour is consistent between animals and years. However, five more instruments will be deployed in the survey season to ensure there is haul-out data concurrent with the survey effort. Some observations of penguins and whales were also made. The accompanying dataset includes three Microsoft Access databases (stored in both Access 97 and Access 2002 formats), as well as two Microsoft Word documents, which provide additional information about these data. The fields in this dataset are: Date Time Time since previous sighting Side (of aircraft/ship) Seen by (observer) Latitude Longitude Number of adults Number of pups Species (LPD - Leopard Seal, WED - Weddell Seal, SES - Southern Elephant Seal, CBE - Crabeater Seal, UNS - Unknown Seal, ADE - Adelie Penguin, ROS - Ross Seal, EMP - Emperor Penguin, MKE - Minke Whale, ORC - Orca Whale, UNP - Unknown Penguin, UNW - Unknown Whale) SpCert - How certain the observer was of correct identification - a tick indicates certainty Distance from Observer (metres) Movement Categories - N: no data, S: stationary, MB: moved body, MBP: moved body and position, movement distance: -99 no data, negative values moved towards flight line, positive distance moved away from flight line Distance dart gun fired from animal (in metres) Approach method (S = ship, H = helicopter, Z = unknown) Approach distance (metres) Group (S = single, P = pair, F = family (male, female and pup)) Sex Guessed Weight (kg) Drugs used Maximum Sedation Level (CS = Colin Southwell, MT = Mark Tahmidjis) Time to maximum sedation level Time to return to normal Heart rate (maximum, minimum) Respiration rate (maximum, minimum, resting) Arousal Level (1 = calm, 2 = slight, 3 = strong) Arousal Level Cat1 (1 = calm, 2 = 2+3 from above) Apnoea (maximum length of apnoea in minutes) Comments Time at depth - reading taken every 10 seconds, and whichever depth incremented upwards by 1. Time period (NT - 21:00-03:00, MN - 03:00-09:00, MD - 09:00-15:00, AF - 15:00-21:00) Seal Age - (A = Adult, SA = sub-Adult) WCId - Wildlife Computers Identification Number for SLTDR Length, width, girth (body, head, flippers) (cm) Blood, blubber, skin, hair, tooth, scat, nasal swab - sample taken, yes or no. In general, Y = Yes, N = No, ND = No Data This work was also completed as part of ASAC projects 775 and 2263.