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OCEAN > SOUTHERN OCEAN > MACQUARIE ISLAND

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  • Metadata record for data from ASAC Project 545 See the link below for public details on this project. From the abstract of the referenced paper: Blood was collected for haematological, red cell enzyme and red cell metabolic intermediate studies from 20 Southern elephant seals Mirounga leonina. Mean haematological values were: haemoglobin (Hb) 22.4 plus or minus 1.4 g/dl, packed cell volume (PCV) 54.2 plus or minus 3.8%, mean cell volume (MCV) 213 plus or minus 5 fl and red cell count (RCC) 2.5 x 10 to power 12 / l. Red cell morphology was unremarkable. Most of the red cell enzymes showed low activity in comparison with human red cells. Haemoglobin electrophoresis showed a typical pinniped pattern, ie two major components. Total leucocyte counts, platelet counts, and coagulation studies were within expected mammalian limits. Eosinophil counts varied from 0.5 x 10 to power 9 / l (5%-49%), and there was a very wide variation in erythrocyte sedimentation rates, from 3 to 60mm/h.

  • The RAN Australian Hydrographic Service conducted hydrographic survey HI176 at Macquarie Island in December 1993. The main survey area was adjacent to the north-east coast between North Head and The Nuggets. Survey lines were also followed part way down the west coast of the island and in the vicinity of Judge and Clerk Islets and Bishop and Clerk Islets. The survey dataset, which includes metadata, was provided to the Australian Antarctic Data Centre by the Australian Hydrographic Office and is available for download from a Related URL in this metadata record. The survey was lead by LT A.J.Withers. The data are not suitable for navigation.

  • The RAN Australian Hydrographic Service conducted hydrographic survey HI242 at Macquarie Island in November and December 1996. The main survey areas were Buckles Bay and Hasselborough Bay. Survey lines were also followed from Elliott Reef down the west coast to Langdon Bay and down the east coast to Buckles Bay. The survey dataset, which includes metadata, was provided to the Australian Antarctic Data Centre by the Australian Hydrographic Office and is available for download from a Related URL in this metadata record. The survey was lead by LT M.A.R.Matthews. The data are not suitable for navigation.

  • Metadata record for data from ASAC Project 2212 See the link below for public details on this project. From the abstracts of two of the references: ---------- Ocean Drilling Program hole 504B revealed an ocean crust hydrothermal sulphur anomaly on the dyke-lava transition, with implications for global sulphur sinks. Here we confirm the presence of the anomaly sporadically along 7.5km of dyke-basalt contact on the Macquarie Ridge at Macquarie Island, a 39-9.7 Ma slow-spreading setting. Background contact-zone pyrite S contents average 1845 ppm across ~50 m. However zones of small-scale brittle faulting that commonly occur on and above the dyke-basalt contact average between 5000 and 11000 ppm S (20-30 m widths). These consist of steep ridge-parallel faults and fault splays on the contact, overlain by up to 50m of linked pyritic fault trellis. The contact zone faults are haloed by disseminated pyrite-chlorite, cross-cut by quartz-chlorite-sphalerite and epidote-cemented breccias, containing evidence of turbulent flow. The structural control on sulphur deposition is attributed to the active extensional slow spreading setting. With increasing extension, diffuse mixing across the contact was replaced by channelised flow and dynamic mixing in fault arrays. The magnitude of the dyke-lava transition sulphur sink must be reassessed to take account of this heterogeneity. ---------- There are only a handful of known hydrothermal sulfate occurrences from the mid-ocean ridge crust sub-surface, despite predictions that they should be common because of the imbalance between sulfur concentrations in venting MOR hotsprings, and that of recharging seawater. This deficit indicates that sub-surface sulfate deposition could be a globally important sulfur cycle sink. Therefore any new occurrences add considerably to the information base on sulfate in this environment. An important hydrothermal sulfate occurrence is preserved in ~10 Ma MOR crust on the east coast of Macquarie Island, formed during very slow oblique spreading prior to transition to a magmatic strike-slip plate boundary. The sulfate occurs mainly as white gypsum veins and breccia cement associated with a major fault zone 400m south of Nuggets Point. The site is in the amphibolite facies sheeted dyke and gabbro screen hanging wall of a major northwest-trending graben, itself filled with sub-ziolite facies basaltic breccias and lava flows. The sulfate veins occur as several 2-5m wide vein complexes, with surrounding vein networks over several hundred metres. Veins are strongly associated with oblique-sinistral jogs on a N to NNE-trending fault zone, here termed the Nuggets fault. This fault is intruded by thin, weakly metamorphosed, vesicular sheeted dykes (forming a greater than 30m wide zone) interpreted to have developed contemporaneously with the nearby graben, Gypsum is mainly in the amphibolite facies rocks and the younger dykes, but also occurs as thin gape-fill in dykes of the younger volcanic graben. These field relations indicte that the sulfate veins were emplaced contemporaneously with graben formation and infill, approximately 200m below the sea floor. The host fault zone is contiguous with mapped graben offsets, and is interpreted as an oblique transfer fault. Secondary epidote and quartz-chalcopyrite veining, together with subsequent chlorite-pyrite alteration, predate sulfate, and suggest early hydrothermal upflow conditions. These are cut by vein complexes which display anhydrite relics within foliated gypsum plus or minus pyrite veins surrounded by marginal vein networks of zeolite-gypsum-calcite. These assemblages require central temperatures of greater than 150 degrees C, with a rapid gradation in outer veins to cooler conditions, perhaps less than 100 degrees C. These features imply general cooler recharge conditions; our previous work has shown that this involved a complex history of sub-surface microbial interaction. These field and mineralogical relations provide one predictive tectonic context for the deposition and style of hydrothermal sulfate in extending MOR crust. Sulfate fluid is strongly fault channeled, and rather than occurring in graben boundary faults, deposits precipitates preferentially in transfer faults under-going limited magmatic activity on the graben edge. A description of the fields in this dataset: m from start: metres measured over the ground between sample points. Easting mE, and Northing mE: estimated position relative to the AMG grid used in the 1;10000 mapping series, Mineral Resources Tasmania, using a horizontal datum of WGS 1984. Map date of production, August 1997.

  • The AADC (Australian Antarctic Data Centre) is in the process of converting all internally held spatial datasets to the ITRF2000 horizontal datum. This consolidated dataset consists of surveys HI623_alatB_gg, HI625_alatB_GG, HI632_alat_B_gg, HI632_alat_C_gg, LADSII_MMI20756_HSDB_T0001_SD_100029052_op, LADSII_MMI20756_HSDB_T0001_SD_100029053_op, LADSII_MMI20756_HSDB_T0001_SD_100029054_op converted to ITRF2000 horizontal datum with Z conversion values for multiple height datums. The data was provided to the AAD by Paul Digney of Jacobs consulting in March 2021. Included survey datasets: • HI623_alatB_gg • HI625_alatB_GG • HI632_alat_B_gg • HI632_alat_C_gg • LADSII_MMI20756_HSDB_T0001_SD_100029052_op • LADSII_MMI20756_HSDB_T0001_SD_100029053_op • LADSII_MMI20756_HSDB_T0001_SD_100029054_op All data are in horizontal datum ITRF2000 and have been combined into a single ESRI geodatabase feature class titled AHS_Surveys_Macca_ITRF2000. Attribute data shows quality information, conversion factors (shift in metres) for multiple datums and the MSL orthometric height: Column Name Alias Meaning Easting Easting Easting ITRF2000 Northing Northing Northing ITRF2000 LAT_to_GRS LAT_to_GRS LAT (Chart Datum) to GSR80 LAT_to_Mac LAT_to_Mac LAT to Macca MSL Z_To_GRS80 Z_To_GRS80 Height to the Ellipsoid Z_To_Macca Z_To_Macca Local MSL orthometric height Vertical_U Vertical_U How good is the Vertical Position Horizontal Horizontal How good is the Horizontal Position Uncertaint Uncertaint Uncertainty Comments Depth_Comm Depth_Comments Vertical uncertainty ranges from 0.5 to 1.2 m and horizontal uncertainty ranges from 2 to 5.5 m. Null values indicate unknown uncertainty. See the attached document ‘Metadata_Record_Macqaurie Island Final.xlsx’ for further details.

  • Marine debris records from beaches on Heard and Macquarie Islands and floating debris spotted on voyages. Data were collected by observers surveying beaches either methodically or opportunistically, and by observers spotting debris as it floated past ships. The data were originally collated into a searchable database, but the application is no longer supported by the Australian Antarctic Data Centre. An extract of the data is attached to this metadata record. The extract is in Excel format, and each worksheet is a copy of a database table.

  • INDICATOR DEFINITION Count of all adult females, fully weaned pups and dead pups hauled out on, or close to, the day of maximum cow numbers, set for October 15. TYPE OF INDICATOR There are three types of indicators used in this report: 1.Describes the CONDITION of important elements of a system; 2.Show the extent of the major PRESSURES exerted on a system; 3.Determine RESPONSES to either condition or changes in the condition of a system. This indicator is one of: CONDITION RATIONALE FOR INDICATOR SELECTION Elephant seals from Macquarie Island are long distance foragers who can utilise the Southern Ocean both west as far as Heard Island and east as far as the Ross Sea. Thus their populations reflect foraging conditions across a vast area. The slow decline in their numbers (-2.3% annually from 1988-1993) suggests that their ocean foraging has been more difficult in recent decades. Furthermore, interactions with humans are negligible due to the absence of significant overlap in their diet with commercial fisheries. This suggests that changes in 'natural' ocean conditions may have altered aspects of prey availability. It is clear that seal numbers are changing in response to ocean conditions but at the moment these conditions cannot be specified. DESIGN AND STRATEGY FOR INDICATOR MONITORING PROGRAM Spatial Scale: Five beaches on Macquarie Island (lat54 degrees 37' 59.9' S, long 158 degrees 52' 59.9' E): North Head to Aurora Point; Aurora Point to Caroline Cove; Garden Cove to Sandy Bay; Sandy Bay to Waterfall Bay; Waterfall Bay to Hurd Point. Frequency: Annual census on 15th October Measurement Technique: Monitoring the Southern Elephant Seal population on Macquarie island requires a one day whole island adult female census on October 15 and a daily count of cow numbers, fully weaned pups and dead pups on the west and east isthmus beaches throughout October. Daily cow counts during October, along the isthmus beaches close to the Station, provide data to identify exactly the day of maximum numbers. The isthmus counts are recorded under the long-established (since 1950) harem names. Daily counts allow adjustment to the census totals if the day of maximum numbers of cows ashore happens to fall on either side of October 15. Personnel need to be dispersed around the island by October 15 so that all beaches are counted for seals on that day. This has been achieved successfully for the last 15 years. On the day of maximum haul out (around 15th October) the only Elephant seals present are cows, their young pups and adult males. The three classes can be readily distinguished and counted accurately. Lactating pups are not counted, their numbers are provided by the cow count on a 1:1 proportion. The combined count of cows, fully weaned pups and dead pups provides an index of pup production. The count of any group is made until there is agreement between counts to better than +/- 5%. Thus there is always a double count as a minimum; the number of counts can reach double figures when a large group is enumerated. The largest single group on Macquarie Island is that at West Razorback with greater than 1,000 cows; Multiple counts are always required there. RESEARCH ISSUES Much research has been done already to acquire demographic data so that population models can be produced. Thus there will be predicted population sizes for elephant seals on Macquarie Island in 2002 onwards and the annual censuses will allow these predictions to be tested against the actual numbers. The censuses are also a check on the population status of this endangered species. LINKS TO OTHER INDICATORS

  • This is a scanned copy of the vertebrate biology report from Macquarie Island by David Slip. The report was split into two documents, and has been scanned as such. The topics covered in the report include: - Elephant seal census - Elephant seal tagging program - Resights of tagged seals - Electrophoretic studies - Blood chemistry - Time depth recorders and satellite telemetry deployment - Pup and weaner weights - Calculation of body fat - Anesthetics - Examination of diet through stomach lavaging - Leopard seals - Survey of marine debris

  • Southern elephant seals are among the deepest diving of all marine mammals. This study examined physiological and behavioural mechanisms used by the seals to conserve energy while diving and estimated metabolic rate. 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).

  • This work was carried out by Graeme Smith between 1966 and 1970 as part of a PhD at the Australian National University. The dataset contains information about penguins killed in 1967 as part of the work. Also available for download is a copy of the thesis. Taken from the introduction of the thesis: Penguins are widely distributed in the Southern Hemisphere. The distribution is circumpolar in the Antarctic and sub-Antarctic regions, and ranges north to the southern coasts of Africa, Australasia and South America, where the range extends northwards up the western coast, and across to the Galapagos Islands. The Galapagos penguin is the most northern species, while the Emperor and the Adelie penguins are confined to the Antarctic. Although most species of penguins are found in the warmer zones of the Southern Hemisphere, and in many cases close to inhabited coasts, comparatively little is known about their biology. By contrast, the biology of the penguins of the remote sub-Antarctic islands and the Antarctic continent is well documented for a number of species. This anomalous situation is probably a result of the great interest shown in the Antarctic regions following Cook's voyages (1768-71 and 1772-75), and the comparatively limited number of species found in these regions. Also see the metadata record for work on Royal Penguins carried out at Macquarie Island between 1955 and 1969 - ID "RoyalPenguin1955-1969".