We implemented a monitoring program developed by Crawford and White (2006), which was designed to assess the current condition of six key estuaries in NW Tasmania: Port Sorell, the Leven, Inglis, Black, Montagu and Arthur River estuaries. This study considered a range of water quality and ecological indictors commonly used to monitor estuaries. These included: salinity, temperature, dissolved oxygen, turbidity, pH, nutrients (nitrate + nitrite, dissolved reactive phosphorus and ammonia), silica molybdate reactive and chlorophyll a for the water column; chlorophyll a and macroinvertebrate community structure amongst the sediments. The data represented by this record was collected in Montagu River.

Seabed areas were derived by aggregating and dissolving the boundaries of the 1 degree S57 file series for the Australian continental shelf and Lord Howe Island shelf (200 m). These areas were defined by the Australian Hydrographic Service (AHS).

Kelps are in global decline due to climate change, including ocean warming. To identify vulnerable species, we need to identify their tolerances to increasing temperatures and whether tolerances are altered by co-occurring drivers such as inorganic nutrient levels. This is particularly important for those with restricted distributions, which may already be experiencing thermal stress. To identify thermal tolerance of the range restricted kelp Lessonia corrugata, we conducted a laboratory experiment on juvenile sporophytes to measure performance (growth, photosynthesis) across its thermal range (4 – 22 °C). We found the upper thermal limit for growth and photosynthesis to be ~ 22 – 23 °C, with an optimum of ~ 16 °C. To determine if elevated inorganic nitrogen availability could enhance thermal tolerance, we compared performance of juveniles under low (4.5 µmol/day) and high (90 µmol/day) nitrate conditions at and above the thermal optimum (16 – 23.5 °C). Nitrate enrichment did not enhance thermal performance at temperatures above the optimum but did lead to elevated growth rates at the thermal optimum 16 °C. Our findings indicate L. corrugata is likely to be extremely susceptible to moderate ocean warming and marine heatwaves. Peak sea surface temperatures during summer in eastern and northeastern Tasmania can reach up to 20 – 21 °C and climate projections suggest that L. corrugata’s thermal limit will be regularly exceeded by 2050 as south-eastern Australia is a global ocean-warming hotspot. By identifying the upper thermal limit of L. corrugata we have taken a critical step in predicting the future of the species in a warming climate.

A total of 111 estuaries of moderate or large size were recognised around Tasmania and associated Bass Strait islands. The catchments of these estuaries were mapped using GIS, and available data on geomorphology, geology, hydrology and rainfall collated for each estuary and catchment area. Tasmanian estuaries were classified into nine groups on the basis of physical attributes that included salinity and tidal data collected during a field sampling program. Baseline information on the abundance, biomass and estimated production of macrobenthic invertebrate species was collected during a quantitative sampling program at 55 sites in 48 Tasmanian estuaries. These data were generally obtained at three different intertidal levels and two shallow subtidal depths at each site, and included information on a total of 390 taxa and over 100,000 individuals. Data on the distribution of 101 fish species, as obtained during surveys of 75 Tasmanian estuaries using seine nets by Last (1983) with some supplementary sampling, were also incorporated into the study.

This study assessed the spatial and temporal (horizontal and vertical) distribution of Asterias amurensis larvae in the Derwent Estuary and adjacent Storm Bay, SE Tasmania. Horizontal transport and development was assessed by collecting plankton samples at 2 or 4 week intervals, from July to December 2001, at 4 sites in the Derwent Estuary and 6 sites in Storm Bay. The effects of light and salinity on vertical distribution of larvae was examined over a 24 hour tidal and diel cycle.

This project undertook a rapid exploration of information on a priority subset of species identified by the Department of Climate Change, Energy, the Environment and Water (DCCEEW) and the National Offshore Petroleum Safety and Environment Authority (NOPSEMA) that are listed as critically endangered or endangered under the Environment Protection and Biodiversity Conservation Act 1999. It specifically focused on these species in relation to the Gippsland declaration area, and the adjacent areas to the declaration area in Bass Strait. This rapid exploration of information was conducted as follows: 1) identify datasets and information sources relevant to priority species identified by DCCEEW and NOPSEMA for the Gippsland declaration area; 2) identify the source of these datasets and information and their level of accessibility; 3) evaluate the utility of datasets and information identified in 2) for assessments/regulatory processes required to be undertaken by DCCEEW and NOPSEMA; and 4) identify what activities would need to be undertaken to improve the accessibility and utility of datasets and information sources identified in 3) that are not currently accessible in useable formats. Fifteen priorities species (12 birds, 3 cetaceans) were identified for which publicly-available occurrence data could be located. This record and the attached download describes the data inventory for North-Eastern Siberian Red Knot (Calidris canutus). To download the data inventory for all fifteen priority species, see https://doi.org/10.25959/GB51-RW44.

This record provides an overview of the NESP Marine and Coastal Hub emerging priorities study - "Application of environmental DNA to survey Bathurst Harbour Tasmania for the endangered Maugean skate". For specific data outputs from this project, please see child records associated with this metadata. -------------------- The Maugean skate (Zearaja maugeana) is listed as Endangered under Tasmania’s Threatened Species Protection Act and the Commonwealth Environmental Protection and Biodiversity Conservation Act 1999. Its known population is small (~3,000 individuals, Macquarie Harbour, 2016) and highly restricted, having only been recorded in two isolated estuaries: Bathurst Harbour and Macquarie Harbour in south-western/western Tasmania. This constitutes one of the most limited distributions of any known extant elasmobranch. Although the skate was first discovered in Bathurst Harbour, most knowledge of the species stems from the Macquarie Harbour population. Only four individuals have been reported in Bathurst Harbour, with the last reported sighting in 1992. Environmental conditions in Macquarie Harbour have changed markedly since then due to anthropogenic activities in and around the estuary including historical mining, hydro-electric generation and alteration of natural river flows, and marine fish farming. Previous research has shown clear signs of population stress and evidence of detrimental impacts of degraded environmental conditions on the Maugean Skate in Macquarie Harbour. Understanding the potential population status of the Maugean Skate in Bathurst Harbour will assist in determining conservation actions. This study used Environmental (e) DNA to determine the presence/absence of the endangered Maugean skate (Zearaja maugeana) in Bathurst Harbour, strengthening the evidence base for effective conservation plans and specific recovery actions. Outputs • Maugean skate eDNA sampling data and inferred species distribution (presence/absence) [dataset] • Final Project Report, including a short summary of recommendations for policy makers of key findings [written]

The following dataset contains particulate iron data collected during the 2018 occupation of the CLIVAR SR03 (GEOTRACES GS01) transect south of Tasmania, Australia. This data is used ancillary to measurements of dissolved iron in the same transect for a manuscript in preparation by Traill et al. (2023). While modelling efforts have furthered our understanding of marine iron biogeochemistry and its influence on carbon sequestration, observations of dissolved iron (dFe) and its relationship to physical, chemical and biological processes in the ocean are needed to both validate and inform model parameterisation. Where iron comes from, how it is transported and recycled, and where iron removal takes place, are critical mechanisms that need to be understood to assess the relationship between iron availability and primary production. To this end, hydrographic and trace metal observations across the GO-SHIP section SR3, south of Tasmania, Australia, have been analysed in tandem with the novel application of an optimum multiparameter analysis. From the trace-metal distribution south of Australia, key differences in the drivers of dFe between oceanographic zones of the Southern Ocean were identified. In the subtropical zone, the source of dFe was constrained by waters advected off the continental shelf, and by remineralization in recirculated modified mode and intermediate water masses of the Tasman Outflow. In the subantarctic zone, the seasonal replenishment of dFe in Antarctic surface and mode waters appears to be sustained by iron recycling in the underlying mode and intermediate waters. In the southern zone, the dFe distribution is likely driven by dissolution and scavenging by high concentrations of particles along the Antarctic continental shelf and slope, entrained in high salinity shelf water. This approach to trace metal analysis may prove useful in future transects for identifying key mechanisms driving marine dissolved trace metal distributions.