Fur seals are re-establishing along the New South Wales coast following historical exploitation, although both New Zealand and Australian fur seals (Arctocephalus forsteri, A. pusillus doriferus) remain listed as Vulnerable in NSW (NSW Office of Environment and Heritage, 2023). As populations recover, interactions with fisheries, marine parks and coastal communities are increasing, highlighting the need for contemporary ecological data to inform management. Concurrently, southern NSW is a climate change hotspot, where shelf waters are warming at more than twice the rate of northern regions due to strengthening heat transport associated with the East Australian Current (EAC) and its eddy field (Malan et al., 2021). However, despite this rapid change, subsurface observations in this highly dynamic region remain comparatively sparse, limiting our understanding of accelerating ocean change and its ecological implications.
This study addresses these dual challenges by positioning fur seals as both species of conservation concern and platforms for ocean observation. Using biologging data from IMOS deployments (2012–2014) and recent SIMS-led tagging (2025), including the first deployments on female fur seals in NSW, we integrate movement, diving behaviour and in situ oceanographic measurements. Instrumented seals act as ‘animal oceanographers’, collecting temperature and depth data throughout the water column in regions that are difficult to sample using conventional infrastructure. This approach is particularly powerful in southern NSW, where subsurface observations disproportionately improve estimates of ocean structure, heat content and transport, and enhance the performance of ocean reanalyses and models in the EAC system (Kerry et al., 2018; Gwyther et al., 2023; Harcourt et al., 2025). As a result, seal-borne observations from this region provide critical insights into ocean dynamics both locally and further north within the EAC system.
By comparing behavioural patterns across species, sex and time, this work identifies key environmental drivers of foraging behaviour and habitat use, and examines how ocean variability influences ecological responses. It also evaluates the quality and utility of animal-borne observations for integration into ocean observing system design and model assimilation.
This research demonstrates how fur seal tracking can inform adaptive management and conservation. Outcomes support the identification of Biologically Important Areas, inform marine park zoning and improve strategies for managing human–wildlife interactions as populations expand. More broadly, the study highlights the value of integrating ecological and oceanographic data to strengthen evidence-based governance in rapidly changing marine systems.