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    Green turtles (Chelonia mydas) are globally endangered and culturally significant to Indigenous Traditional Owners in northern Australia, yet fine-scale understanding of their foraging habitats remains poorly understood, especially along Australia's remote north-coast. This project mapped green turtle foraging habitats in the Northern Territory, through collaboration with Indigenous Traditional Owners and ranger groups, to assist with their sea country management. Visual classifications of towed video transect data were used in a Support Vector Machine Learning Model to predict habitat in 379 km² of remotely sensed satellite imagery, overlapping the benthic habitats for two green turtle foraging grounds within the joint managed parks: Trepang Bay, Garig Gunak Barlu Marine Park, and Field Island, Kakadu National Park. Algae and seagrass made up 30% of the Trepang Bay and 18.05% of the Field Island foraging turtle habitat. The classification accuracy of the model showed a high level of agreement at both sites (0.63 for Trepang Bay and 0.75 for Field Island). These habitats provide good foraging grounds for green turtles and the diversity of marine habitats also allows for a range of different age classes of green turtles to use these sites for a range of other behaviours, e.g. resting and predator avoidance. The simplicity and repeatability of the field methods used in this study allow for future monitoring of marine habitats in remote areas by ranger groups. The findings are useful for conservation planning, including the development of management plans in the Northern Territory.

  • This record provides an overview of the scope and research output of NESP Marine Biodiversity Hub Project A12 - "Scoping a seascape approach to managing and recovering Northern Australian threatened and migratory marine species". For specific data outputs from this project, please see child records associated with this metadata. -------------------- Northern Australia is the current focus of substantial economic development, which has the potential to impact biodiversity and cultural values. The Northern Seascape scoping project will assess the status of knowledge of EPBC-listed Threatened and Migratory Marine species, and pressures, Indigenous priorities, habitats, fisheries bycatch, and EPBC referrals in relation to them across the North Marine Bioregion (coast to EEZ edge). The focus will be at the multiple taxa level, including elasmobranchs, shorebirds, turtles and cetaceans. The project will scope research needs and directions for a broad Northern Seascape project (2018–2020), by identifying future research hotspots. Planned Outputs • Maps of Threatened and Migratory Marine species occurrence and habitats, and a gap analysis of research and data needs • Maps of state and trends in pressures and Threatened and Migratory Marine species, and the intersection between them • A report on Indigenous marine research and management priorities for Threatened and Migratory Marine species • Maps and time-series graphs that depict the extent and timing of past changes in coastal habitats that are important for TMM species • Identification of Threatened and Migratory Marine species bycatch and bycatch mitigation research priorities • Identification of EPBC referral spatial and species trends • Data, data visualisation and summaries available online through an appropriate web-based portal and/or existing internal DoEE information products • Project report synthesizing northern Australian Threatened and Migratory Marine species, pressures, Indigenous priorities, coastal habitat change, fisheries bycatch mitigation research priorities, and EPBC referral trends, and the identification of future research hotspots

  • This record provides an overview of the scope and research output of NESP Marine Biodiversity Hub Project A1 - "Northern Australian hotspots for the recovery of threatened euryhaline species". For specific data outputs from this project, please see child records associated with this metadata. -------------------- Euryhaline elasmobranchs represent over half of the EPBC-listed threatened sharks and rays, with northern Australia of national importance for this threatened species community. Critical information gaps remain, limiting the implementation of Recovery Plan objectives. This project will fill many data gaps through the application of acoustic telemetry, traditional and advanced molecular research (population genetics and close-kin mark-recapture), life history studies and Indigenous knowledge and education. End-users, primarily the Department of the Environment, state and territory fisheries and wildlife agencies, and Indigenous organisations, will be provided with information necessary to improve management and facilitate recovery of these threatened species, focusing on three themes: (1) Monitoring and understanding euryhaline species; (2) Indigenous partnerships for management of euryhaline species, and; (3) Knowledge for the reassessment of river shark status. Planned Outputs • Updated assessment of river shark status • Manuscripts on ecology and status relevant to the management of threatened euryhaline species • Manuscripts on optimal design of acoustic receiver arrays and statistical methods for estimating mortality • Threatened marine species education package for Indigenous communities • Media releases around key field and engagement activities • Data and information outputs of this project will include distribution, extent of occurrence and area of occupancy estimates for key marine species, Indigenous knowledge on key species distribution and occurrence, mortality and survivorship data on key species, the first data on river shark age determination (an essential component of understanding demography), molecular data on population structure and population connectivity of key species, and lower population size estimate for Glyphis garricki. Data will be housed on appropriate explorable databases and made fully available to DOE • Refining the identification of biologically important areas (BIAs) within the NT and WA for threatened euryhaline elasmobranchs (using published BIA protocols)