Sharon Every is a NAMRA scholarship holder and is presently a PhD candidate at Charles Darwin University (RIEL). She is studying the ecological niche of euryhaline elasmobranchs (estuarine sharks and rays) in the South Alligator River in the Northern Territory.
Sharon has a double degree in Natural Resource Management (AppSc) and Secondary Education from Deakin University (Melbourne). Her honours project was completed at Northern Territory University (now CDU) studying disturbances on tropical rocky shores under the supervision of Dr. Keith McGuinness.
Dr. David Crook (CDU), Dr. Emilie- Jane Ens (ANU), Dr. Peter Kyne (CDU), Dr. Thor Saunders (NT Gov), Prof. Karen Edyvane (CDU)
The ecological niche of a species is important to define, as it enables the protection of a species for their intrinsic value and the maintenance of a healthy, functioning ecosystem. Globally, euryhaline elasmobranchs (estuarine sharks and rays) are at risk due to the location of their habitat and exposure to fisheries. Due to the largely pristine rivers of the Northern Territory these waterways are considered a global stronghold for these species. This project will draw upon two knowledge systems – both, western scientific conceptual frameworks (i.e. niche theory) and also, Indigenous Ecological Knowledge (IEK) in the South Alligator and Roper Rivers. Indigenous Australians have been living alongside these rivers for thousands of years and have gained significant knowledge about this environment. Their knowledge may offer significant insights into these species and their ecology.
Two aspects of ecological niche will be studied, trophic and spatial. Trophic niche will be determined by lipid and stable isotope analyses using muscle tissue collected by a biopsy. The spatial niche aspect will be centred on the Bull Shark, Carcharhinus leucas. Acoustic tags will be inserted internally and receivers placed in strategic spots in the river and estuary. To collect IEK a range of Participatory Action Research tools will be used within surveys and semi-structured interviews.
By understanding the spatial and trophic niches of euryhaline elasmobranchs, critical habitats and key prey species will be recognised. This will enable accurate and effective protections strategies to be developed.