Keyword

EARTH SCIENCE > BIOSPHERE > ECOSYSTEMS > MARINE ECOSYSTEMS > COASTAL

77 record(s)
 
Type of resources
Topics
Keywords
Contact for the resource
Provided by
From 1 - 10 / 77
  • Geoscience Australia, the Royal Australian Navy (RAN) and the Australian Antarctic Division (AAD) conducted a hydrographic and seafloor characterisation survey in nearshore waters offshore from Davis Station in the Australian Antarctic Territory. Multibeam bathymetry data was acquired during January-February 2017 and a high-resolution (2 m) bathymetry grid produced for the survey area.

  • Geoscience Australia, the Royal Australian Navy (RAN) and the Australian Antarctic Division (AAD) conducted a hydrographic and seafloor characterisation survey in nearshore waters offshore from Davis Station in the Australian Antarctic Territory. Multibeam data was acquired during January-February 2017 and a high-resolution (2 m) backscatter grid produced for the survey area.

  • Rapid toxicity tests (Kefford et al. 2005) were used to test the sensitivity of a wide range of intertidal and shallow sub-tidal marine invertebrates collected off the northern end of Macquarie Island. The tests were 10 days long, with a water change at 4 days. Resulted in the data set are non-modelled LCx (concentrations lethal to x% of the test populations) values for Copper (Cu) 10 days of exposure. Kefford, B.J., Palmer, C.G., Jooste, S., Warne, M.St.J. and Nugegoda, D. (2005). What is it meant by '95% of species'? An argument for the inclusion of rapid tolerance testing. Human and Ecological Risk Assessment 11: 1025-1046. Invertebrates collected from a range of coastal waters off the northern end of Macquarie Island . The columns in the spreadsheet are as follows: Lowest ID = the lowest identification the taxa is ID to (can be species, genus, family, etc.) Group = major taxonomic group the taxa comes from Letter = a convent identifier to split the taxa LC50 discpt = a string description of the10 day LC50 (lethal concentration for 50% of the test population) LC50 point estimate = a point estimate of the 10 day LC50 (lethal concentration for 50% of the test population) Cencor = indicates if the LC50 is right censored (that is greater than the value indicated in the point estimate) Case = a number to identify the record Project Public Summary: Despite pollution concerns in Antarctic and southern oceans, there is little ecotoxicological data and none from the sub-Antarctic. Ecological risk assessments and water quality guidelines should use local data, especially in the polar environment as organisms may respond differently to pollutants. The sub-Antarctic is, however, between Antarctica and the temperate zone and in the absence of local data, it maybe appropriate to use temperate data. This project will assess how the sensitivity to metals of marine invertebrates varies latitudinally and in which region of the Antarctic, if at all, it is appropriate to use temperate data.

  • The concentration of heavy metals in seawater at four sites around Casey was determined via Diffusive Gradients in Thin films (DGT) loggers attached to experimental mesocosms suspended below the sea ice. Data are the concentration of heavy metals in micrograms per litre (ug/l), equivalent to parts per billion (ppb)/litre Two loggers were attached to each mesocosm (perforated 20 litre food buckets) at each site; one at the top and one at the bottom of each mesocosm. Mesocosms were suspended two to three metres below the bottom edge of the sea ice through a 1 metre diameter hole and were periodically raised to the surface for short periods (~1 hour). This experiment was part of the short-term biomonitoring program for the Thala Valley Tip Clean-up at Casey during summer 2003/04. During Runs 1 and 2 of the experiment mesocosms were deployed at Brown Bay Inner (S66 16.811 E110 32.475), Brown Bay Outer (S66 16.811 E110 32.526), McGrady Cove (S66 16.556 E110 34.392) and O'Brien Bay 1 (S66 18.730 E110 30.810). In Run 3 mesocosm were deployed in open water with no sea ice covering at Brown Bay Inner (S66 16.807 E110 32.556), Brown Bay Outer (S66 16.805 E110 32.607), McGrady Cove (S66 16.520 E110 34.257) and O'Brien Bay (S66 17.607 E110 31.247). These data were collected as part of ASAC project 2201 (ASAC_2201 - Natural variability and human induced change in Antarctic nearshore marine benthic communities). See also other metadata records by Glenn Johnstone for related information.

  • This dataset collates data on occupancy of geographic sites by breeding Adelie penguins across east Antarctica between 37 degrees E -160 degrees E from the 1950s to the present day. A separate dataset contains a table and maps of geographic sites in East Antarctica where Adelie penguins could potentially breed. This occupancy dataset comprises a table of breeding sites and a table of occupancy observations. The breeding site table has a list of the geographic sites where breeding Adelie penguins have been observed at least once. The table contains for each breeding site, the names used for each site in the literature, the literature sources for those names, the geographic centroid of the breeding location within the geographic site, and any comments to help interpret the breeding site. The occupancy table contains observations of the presence or absence of breeding Adelie penguins at each breeding site and split-year breeding season obtained from the published primary and secondary literature and from the researchers' unpublished data. These data also include occupancy survey data collected as part of ASAC 2722 - see the related metadata record for more information.

  • Ecologists are increasingly turning to historical abundance data to understand past changes in animal abundance and more broadly the ecosystems in which animals occur. However, developing reliable ecological or management interpretations from temporal abundance data can be difficult because most population counts are subject to measurement or estimation error. There is now widespread recognition that counts of animal populations are often subject to detection bias. This recognition has led to the development of a general framework for abundance estimation that explicitly accounts for detection bias and its uncertainty, new methods for estimating detection bias, and calls for ecologists to estimate and account for bias and uncertainty when estimating animal abundance. While these methodological developments are now being increasingly accepted and used, there is a wealth of historical population count data in the literature that were collected before these developments. These historical abundance data may, in their original published form, have inherent unrecognised and therefore unaccounted biases and uncertainties that could confound reliable interpretation. Developing approaches to improve interpretation of historical data may therefore allow a more reliable assessment of extremely valuable long-term abundance data. This dataset contains details of over 200 historical estimates of Adelie penguin breeding populations across the Australian Antarctic Territory (AAT) that have been published in the scientific literature. The details include attributes of the population count (date and year of count, count value, count object, count precision) and the published estimate of the breeding population derived from those attributes, expressed as the number of breeding pairs. In addition, the dataset contains revised population estimates that have been re-constructed using new estimation methods to account for detection bias as described in the associated publication. All population data used in this study were sourced from existing publications.

  • This dataset comprises a table and set of maps of all geographic sites of ice-free land along the East Antarctica coastline between longitudes 37°E and 160°E. Each geographic site comprises a discrete area of ice-free land and includes islands within 100 km of the coast and outcrops of ice free continental rock within 1 km of the coast. The geographic sites were identified in a geographic information system using polygons sourced from the AAT Coastline 2003 dataset produced by Geoscience Australia and the Australian Antarctic Division, and exposed rock polygons sourced from the Antarctic Digital Database version 4.0 produced for the Scientific Committee on Antarctic Research. The maps are grouped into sub-regions and regions, with multiple maps in most sub-regions. The maps were designed to be of a scale that could be used in the field to identify sites by their shape and location. This dataset has previously been used in the specific context of potential breeding habitat for Adelie penguins (doi:10.4225/15/5758F4EC91665) but has potential for broader use in a wide range of ecological and environmental studies. 2021-06-30 - an updated copy of the spatial reference system spreadsheet was uploaded. The update was only minor.

  • The salinity of seawater at four sites around Casey was recorded during summer 2003/04 by a salinity probe (TPS Australia, WP-84 Conductivity Meter) attached to experimental mesocosms suspended below the sea ice. Data are salinity in parts per thousand (ppk) automatically logged every 30 minutes over the two two week long runs of the experiment. The period over which data were recorded varies between sites and is fragmentary within these periods at some sites due to power lose to the loggers caused by faulty batteries and adverse weather conditions. Mesocosms were suspended two to three metres below the bottom edge of the sea ice through a 1 metre diameter hole and were periodically raised to the surface for short periods (~1 hour). Mesocosms were deployed at Brown Bay Inner (S66 16.811 E110 32.475), Brown Bay Outer (S66 16.811 E110 32.526), McGrady Cove (S66 16.556 E110 34.392) and O'Brien Bay 1 (S66 18.730 E110 30.810). This experiment was part of the short-term biomonitoring program for the Thala Valley Tip Clean-up at Casey during summer 2003/04. These data were collected as part of ASAC project 2201 (ASAC_2201 - Natural variability and human induced change in Antarctic nearshore marine benthic communities). See also other metadata records by Glenn Johnstone for related information.

  • Adult Weddell seals (Leptonychotes weddellii) exhibit site fidelity to where they first breed but juveniles, and perhaps transient adult males, may disperse from their natal location. If there is mixing between adjacent breeding groups, we would expect that common vocalisations would exhibit clinal patterns. Underwater Trill vocalisations of male Weddell seals at Mawson, Davis, Casey, McMurdo Sound, Neumayer and Drescher Inlet separated by ca. 500 to greater than 9,000 km, were examined for evidence of clinal variation. Trills are only emitted by males and have a known territorial defence function. Trills from Davis and Mawson, ca. 630 km apart, were distinct from each other and exhibited the greatest number of unique frequency contour patterns. The acoustic features (duration, waveform, frequency contour) of Trills from Neumayer and Drescher Inlet, ca. 500 km apart, were more distinct from each other than they were from the other four locations. General Discriminant Analysis and Classification Tree Analysis correctly classified 65.8 and 76.9% of the Trills to the correct location. The classification errors assigned more locations to sites greater than 630 km away than to nearest neighbours. Weddell seal Trills exhibit geographic variation but there is no evidence of a clinal pattern. This suggests that males remain close to single breeding areas throughout their lifetime. This work was completed as part of ASAC project 1132 and 2122 (ASAC_1132, ASAC_2122).

  • A report completed as part of this project is available for download from the URL given below. Extracts of the report are presented in the metadata record. See the report for full details. Several species of Antarctic fish were collected from the shallow waters off Davis Station during the 2000-01 season as part of a study examining the properties of 'antifreeze' proteins contained within the blood of these animals. Fish were sampled at regular intervals from a range of depths and various sites near the station. The main objectives of the study were to collect serum and selected tissues from Nototheniid (cod) and Channichthyid (ice fish) species. Over 170 fish were collected throughout the calendar year. Samples were taken as required, processed and the fish preserved for further analysis on return to Australia. In Australia the serum will be tested for special antifreeze molecules that allow these animals to live in water that is colder than the usual freezing point of their body fluids. Such molecules, once identified, may be synthesised in a laboratory, and have numerous potential practical applications, from the preservation of frozen foods, to preservation of blood plasma and organs for human transplant. Analyses of this nature will be undertaken at the University of Sydney.