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EARTH SCIENCE > BIOSPHERE > ECOSYSTEMS > MARINE ECOSYSTEMS > COASTAL

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  • 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.

  • 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.

  • 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.

  • 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 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.

  • 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.

  • 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.

  • 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.

  • Depth related changes in sediment characteristics and the composition of infaunal invertebrate communities were investigated at two sites in the Windmill Islands around Casey station, East Antarctica, during the 2006/07 summer. Sediment characteristics were investigated via sediment cores (5cm deep x 5cm diameter) collected from 4 depths (7m, 11m, 17, and 22m) from each of three transects at two sites (McGrady Cove and O'Brien Bay 1). Measured sediment characteristics included grain size distribution, total organic carbon and the concentration of a range of heavy metals. This work was conducted as part of ASAC 2201 (ASAC_2201).

  • A hierarchical, 3-level, nested design was used. The highest hierarchical level consisted of six locations. Two of these locations, Brown Bay and Shannon Bay, have been contaminated with heavy metals (Stark et al., 2003; Snape et al., 2001); Brown Bay has also been contaminated with petroleum hydrocarbons (Snape et al., 2001). The remaining four locations are more distant from Casey Station and were used as control locations. These locations were Denison Island, Odbert Island, O'Brien Bay and Sparkes Bay. A full description of these sites is given below. Within each location two sites were selected approximately 100 m apart. Within each site, two plots were sampled (~ 10 m apart). Although the sampling program had been designed for four replicates within each plot, the patchy distribution of bottom sediments in the Windmill Islands restricted this to two replicate samples (~ 1 m apart) per plot. Samples were collected using an Eckman grab sampler, deployed from a boat. To minimise the potential influence of water depth, all samples were collected from 8 m water depth. Samples were collected within a three day period in early February when no sea-ice was present. Diatom data are presented as the relative abundances of benthic species. Samples are identified xyz where x = first initial of sample location (or first 2 initials where 2 locations start with the same letter), y = plot number (plots 1 and 2 represent site 1, while plots 3 and 4 are from site 2), and z = replicate number (a or b). Abbreviations used for species are shown in the separate file sp_list. This work was completed as part of ASAC project 1130 (ASAC_1130) and project 2201 (ASAC_2201). Public summary from project 1130: Algal mats grow on sea floor in most shallow marine environments. They are thought to contribute more than half of the total primary production in many of these areas, making them a critical food source for invertebrates and some fish. We will establish how important they are in Antarctic marine environments and determine the effects of local sewerage and tip site pollution. We will also investigate the impact on the algal mats of the additional UV radiation which results from the ozone hole. Public summary from project 2201: As a signatory to the Protocol on Environmental Protection to the Antarctic Treaty Australia is committed to comprehensive protection of the Antarctic environment. This protocol requires that activities in the Antarctic shall be planned and conducted on the basis of information sufficient to make prior assessments of, and informed judgements about, their possible impacts on the Antarctic environment. Most of our activities in the Antarctic occur along the narrow fringe of ice-free rock adjacent to the sea and many of our activities have the potential to cause environmental harm to marine life. The Antarctic seas support the most complex and biologically diverse plant and animal communities of the region. However, very little is known about them and there is certainly not sufficient known to make informed judgements about possible environmental impacts The animals and plants of the sea-bed are widely accepted as being the most appropriate part of the marine ecosystem for indicating disturbance caused by local sources. Attached sea-bed organisms have a fixed spatial relationship with a given place so they must either endure conditions or die. Once lost from a site recolonisation takes some time, as a consequence the structure of sea-bed communities reflect not only present conditions but they can also integrate conditions in the past. In contrast, fish and planktonic organisms can move freely so their site of capture does not indicate a long residence time at that location. Because sea-bed communities are particularly diverse they contain species with widely differing life strategies, as a result different species can have very different levels of tolerance to stress; this leads to a range of subtle changes in community structure as a response to gradually increasing disturbance, rather than an all or nothing response. This project will examine sea-bed communities near our stations to determine how seriously they are affected by human activities. This information will be used to set priorities for improving operational procedures to reduce the risk of further environmental damage. The fields in this dataset are: Species Site Abundance Benthic