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  • This record provides an overview of the scope and research output of the NESP Marine Biodiversity Hub project "Estimation of population abundance and mixing of southern right whales in the Australian and New Zealand regions". For specific data outputs from this project, please see child records associated with this metadata. -------------------- A comprehensive understanding of the population abundance and degree of spatial connectivity of southern right whales in Australian waters is currently lacking. This limits assessments of the species recovery and understanding of the nature and degree of difference between the south-eastern and south-western Australian populations. This project will provide, for the first time, an abundance estimate of the total Australian population of southern right whales. It will also investigate the connectedness of whales that utilise breeding areas on the eastern, southern and western coasts of Australia. Information provided by this project will allow the Australian government to better evaluate progress made against the Conservation Management Plan for southern right whales and ensure conservation efforts for the species are effectively coordinated at the regional level. Planned Outputs • Data summaries for populating models used to estimate abundance and connectivity • An estimate of population abundance at the national scale and associated uncertainty • An evaluation of movement and spatial mixing across southern Australia

  • This record provides an overview of the NESP Marine and Coastal Hub project "Updating knowledge of Australian white sharks". For specific data outputs from this project, please see child records associated with this metadata. -------------------- The white shark is listed as Vulnerable and Migratory under Australia’s Environment Protection and Biodiversity Conservation (EPBC) Act 1999. Previous NESP-funded research provided updated estimates of breeding population size and trend, but uncertainty remained around juvenile nursery and pupping areas, movement patterns, and connectivity between eastern and south-western Australian populations. More recent evidence has also raised the possibility of a single Australian population. This project aimed to reduce uncertainty in the status, trends and population structure of white sharks in Australian waters, with a focus on identifying biologically important habitats and improving population assessment through expanded close-kin mark-recapture (CKMR) analyses. The project combined three major components: (1) pilot tagging studies of large adult females and juvenile sharks to improve understanding of movements, pupping areas and habitat use; (2) genetic analyses to assess stock structure and connectivity using samples collected across Australia, and where possible from South Africa and New Zealand; and (3) updated population assessment using expanded tissue sample collections and close-kin mark-recapture methods. Population estimates incorporated approximately 1,000 tissue samples from New South Wales together with additional samples from South Australia and Western Australia. Juvenile abundance information from the New South Wales shark management program was also integrated into the assessment framework. CKMR approaches used genetic identification of parent-offspring and half-sibling relationships to estimate adult abundance, survival and population trends. Project outputs included updated estimates of population size and trend, improved understanding of population connectivity and movement patterns, and refined information on potential nursery and critical habitat areas. These findings support white shark recovery planning, future monitoring design, and conservation assessment in Commonwealth and state waters. Outputs • New genetic samples and sequencing data for white sharks [dataset] • Tracking data from PAT tags [dataset] • Final technical report (including recommendations for systematic future research to assist in identifying additional critical habitat for the south-western white shark population) [written]

  • This record provides an overview of the NESP Marine and Coastal Hub Research Plan 2023 project "Delineation and estimation of the Maugean skate population in Macquarie Harbour, Tasmania". No public data outputs are planned for this project. -------------------- The Maugean skate (Zearaja maugeana) is now only found in Macquarie Harbour on Tasmania’s west coast, which has a long history of environmental degradation. The species is listed as Endangered under Commonwealth and Tasmanian legislation, and its restricted distribution, small population size, and exposure to degraded environmental conditions make population monitoring a high conservation priority. Recent research suggests that the Macquarie Harbour population may be declining. However, existing abundance estimation methods are inadequate because the species is cryptic, capture-based methods pose risks to skate health, and conventional optical surveys are limited by the harbour’s shallow, stratified, and highly turbid conditions. This project developed and tested new approaches to estimate and monitor the Maugean skate population using next-generation genetic sequencing and novel imaging technologies. Non-invasive acoustic methods (adaptive resolution imaging sonar (ARIS), synthetic aperture sonar, performed better than optical approaches (LiDAR, conventional video), under Macquarie Harbour conditions. ARIS was identified as the most suitable image-based monitoring tool for future population surveys. The genetic component generated the first reference-quality whole and mitochondrial genomes for the species and sequenced samples from 162 individuals. Genome-wide single nucleotide polymorphism (SNP) analyses showed that the Macquarie Harbour population has very low genetic diversity, which may influence how genetic risks are interpreted in recovery planning. The project produced new monitoring methodologies, genomic reference resources, and population genetic datasets to support future monitoring of Maugean skate abundance, population structure, and genetic health. The findings will inform conservation planning and evaluation of recovery strategies including captive breeding, translocation, and long-term genetic monitoring under changing environmental conditions. Outputs • Tissue sampling results and genome-wide population genetic structure [dataset] • Final project report [written]