NESP MB Project A14 - Identification of near-shore habitats of juvenile white sharks in south-western Australia, 2019-2020 (CSIRO)

This record provides an overview of the scope of the NESP Marine Biodiversity Hub project "Identification of near-shore habitats of juvenile white sharks in south-western Australia". No data outputs were generated by this project. -------------------- In 2018, CSIRO provided the first estimate of adult abundance for the southern-western Australian white shark (Carcharodon carcharias) population. At the time, total population abundance could not be estimated because of limited information on the juvenile life-history stage. This project investigated whether juvenile white sharks from this population use near-shore habitats near the head of the Great Australian Bight. It investigated credible anecdotal evidence of juvenile white shark presence in the region and was designed as a pilot study to inform future survey and project development. The project reviewed existing sources of evidence and undertook unmanned aerial vehicle (AUV) surveys in near-shore habitats within and around the Nuyts Archipelago Marine Park. Thirty-five UAV flights were completed during 2018 and 2019, covering approximately 7.5 km². No white sharks were identified in the UAV footage, although several other marine species and shorebirds were observed. Additional evidence from scientific surveys indicated that the Head of Bight and surrounding marine park areas may be important habitat for white sharks across multiple life stages. The project included engagement with the Yalata Land Management Indigenous Ranger team, who were consulted during project planning and survey activities. The findings informed future project development by assessing the value of further on-water activities, expanded UAV surveys and targeted monitoring in the Great Australian Bight region.

NESP MB Project D6 - Socioeconomic benchmarks

This record provides an overview of the scope and research output of the NESP Marine Biodiversity Hub project "Socioeconomic benchmarks". For specific data outputs from this project, please see child records associated with this metadata. -------------------- Social and economic values are key drivers for marine science and marine policy but are too rarely integrated with marine biodiversity monitoring programs. In close consultation with Parks Australia (PA) we will review existing metrics used to survey social and economic values associated with marine parks. This review will include consulting with national and international expertise and actively consulting with State and other Commonwealth agencies, some of whom are currently conducting reviews or have existing frameworks for surveying social and economic values (e.g Great Barrier Reef Marine Park Authority (GBRMPA), NSW Department of Primary Industries (DPI)). In collaboration with national partners and PA we will organise a national methods workshops to discuss and refine metrics and methods to quantify social and economic benchmarks for State and Australian Marine Parks (AMPs) and produce Standard Operating Procedure’s (SOP) relevant to AMPs taking into consideration the Department of the Environment and Energy’s (DoEE’s) environmental accounting processes and PA’s Monitoring, Evaluation, Reporting and Improvement (MERI) framework. Planned Outputs • SOP for measuring social and economic metrics for AMPs • Final report on essential (key) AMP social and economic metrics • Summaries of research and surveys made available through the Marine Parks Science Atlas

Chemical microenvironment within complex multispecies macroalgae assemblages

-- Layton et al. Chemical microenvironments within macroalgal assemblages: implications for the inhibition of kelp recruitment by turf algae. Limnology & Oceanography. DOI:10.1002/lno.11138 -- Kelp forests around the world are under increasing pressure from anthropogenic stressors. A widespread consequence is that in many places, complex and highly productive kelp habitats have been replaced by structurally simple and less productive turf algae habitats. Turf algae habitats resist re-establishment of kelp via recruitment inhibition; however little is known about the specific mechanisms involved. One potential factor is the chemical environment within the turf algae and into which kelp propagules settle and develop. Using laboratory trials, we illustrate that the chemical microenvironment (O2 concentration and pH) 0.0–50 mm above the benthos within four multispecies macroalgal assemblages (including a turf-sediment assemblage and an Ecklonia radiata kelp-dominated assemblage) are characterised by elevated O2 and pH relative to the surrounding seawater. Notably however, O2 and pH were significantly higher within turf-sediment assemblages than in kelp-dominated assemblages, and at levels that have previously been demonstrated to impair the photosynthetic or physiological capacity of kelp propagules. Field observations of the experimental assemblages confirmed that recruitment of kelp was significantly lower into treatments with dense turf algae than in the kelp-dominated assemblages. We demonstrate differences between the chemical microenvironments of kelp and turf algae assemblages that correlate with differences in kelp recruitment, highlighting how degradation of kelp habitats might result in the persistence of turf algae habitats and the localised absence of kelp.

Project A5 - Hammerhead connectivity movement csv location files

CSV files of location data (position estimates) for hammerhead sharks tagged with Wildlife Computers miniPAT archival tags and SPOT6 tags. Note that miniPAT data estimates may be up to 100 km (Kevin Lay, Wildlife computers pers comm). Location estimates from archival miniPAT tags also need to be considered against ARGOS location classes (see http://www.argos-system.org/manual/3-location/34_location_classes.htm). Collectively, movements are restricted within state waters with no hammerheads moving across state or International boundaries.

Drift-kelp suppresses foraging movement of overgrazing sea urchins

Sea urchins have the capacity to destructively overgraze kelp beds and cause a wholesale shift to an alternative and stable ‘urchin barren’ state. However, their destructive grazing behaviour can be highly labile and contingent on behavioural shifts at the individual and local population level. Changes in supply of allochthonous food sources, i.e. availability of drift-kelp, is often suggested as a proximate trigger of change in sea urchin grazing behaviour, yet field tests of this hypothesis are rare. Here we conduct a suite of in situ behavioural surveys and manipulative experiments within kelp beds and on urchin barrens to examine foraging movements and evidence for a behavioural switch to an overgrazing mode by the Australian sea urchin Heliocidaris erythrogramma (Echinometridae). Tracking of urchins using time-lapse photography revealed urchin foraging to broadly conform to a random-walk-model within both kelp beds and on barren grounds, while at the individual level there was a tendency towards local ‘homing’ to proximate crevices. However, consistent with locally observed ‘mobile feeding fronts’ that can develop at the barrens-kelp interface, urchins were experimentally inducible to show directional movement toward newly available kelp. Furthermore, field assays revealed urchin grazing rates to be high on both simulated drift-kelp and attached kelp thalli on barren grounds, however drift-kelp but not attached kelp was consumed at high rates within kelp beds. Time-lapse tracking of urchin foraging before/ after the controlled addition of drift-kelp on barrens revealed a reduction in foraging movement across the reef surface when drift-kelp was captured. Collectively results indicate that the availability of drift-kelp is a pivotal trigger in determining urchin feeding modes, which is demonstrably passive and cryptic in the presence of a ready supply of drift-kelp. Recovery of kelp beds therefore appears possible if a sustained influx of drift-kelp was to inundate urchin barrens, particularly on reefs where local urchin densities and where grazing pressure is close to the threshold enabling kelp bed recovery.

Dredge Samples from IN2018_V08

Rock samples were dredged from seamounts in the southern Tasman Sea on the RV Investigator, voyage IN2018_V08

Krill Fatty Acid Data

The fatty acid content and composition of the Antarctic krill Euphausia superba Dana, 1850 were investigated using samples collected by a commercial fishing vessel. This dataset allowed comparison between seasons, years (2013–2016), and different fishing locations. Quantities of omega 3 fatty acids 20:5n-3 and 22:6n-3 (mg/g dry mass; DM) were highest in autumn and decreased through winter to reach a spring low. Quantities of the flagellate marker 18:4n-3 and diatom marker 16:1n-7c were variable and did not display the same seasonal fluctuations. In summer, krill had high percentages (% total fatty acids) of 20:5n-3 and 22:6n-3, total PUFA, and low 18:1n-9c/18:1n-7c ratios, indicating a more herbivorous diet. Krill became more omnivorous from autumn to spring, indicated by increasing ratios of 18:1n-9c/18:1n-7c and percentages of Σ 20:1 + 22:1 isomers. Bacterial fatty acids (Σ C15 + C17 + C19 isomers) were minor components year-round (0.9–1.8 %). Seasonal levels of herbivory and omnivory differed between years, and levels of specific fatty acid ratios differed between fishing locations. The fatty acid 18:4n-3 was a major driver of variability in krill fatty acid composition, with no obvious seasonal driver. This is the first study to report krill fatty acid data during all four seasons over consecutive years. This large-scale study highlights the value of using fisheries samples to examine seasonal and annual fluctuations in krill diet and condition.

AUSTEn Clarence Strait Moorings

The AUStralian Tidal Energy (AUSTEn) project was a three year project (2018 - 2020) funded by the Australian Renewable Energy National Agency (agreement number G00902) led by the Australian Maritime College (University of Tasmania), in partnership with CSIRO and University of Queensland. The project had a strong industry support (Atlantis Resources Limited, MAKO Tidal Turbines Ltd, Spiral Energy Corporation Ltd). The aim of the project was to assess the technical and economic feasibility of tidal energy in Australia, based on the best understanding of resource achievable. For further information and output of the project, please visit the AUSTEn project website www.austen.org.au.

NESP MB Project E6 - Assisting the restoration of seagrasses at Shark Bay

This record provides an overview of the scope and research data outputs of the NESP Marine Biodiversity Hub project "Assisting the restoration of seagrasses at Shark Bay". For specific data outputs from this project, please see child records associated with this metadata. -------------------- This project is a collaboration between scientists and the Shark Bay Malgana Indigenous community into jointly developed seeding and shoot planting methods to assist natural recovery of seagrasses in preparation for future devastating impacts of climate change. The Shark Bay World Heritage Site (WHS) is unique globally for its natural values, including stromatolites, seagrass meadows and marine megafauna including dugongs, sharks, turtles, and dolphins. The immediate goal is to scale up the existing restoration research to assist recovery of the dominant seagrasses, Amphibolis antarctica and Posidonia australis following the 2011 marine heat wave. Planned Outputs • A seagrass restoration toolkit (multimedia and report format) - will include information on sourcing suitable genetic material • Data on the trial seed restoration outcomes

NESP MB Project A13 - Estimation of population abundance and mixing of southern right whales in the Australian and New Zealand regions, 2018-2020 (CSIRO)

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 (Eubalaena australis) 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 brought together existing photo-identification datasets, including records held in the Australian Right Whale Photo-Identification Catalogue (ARWPIC), to support a national assessment of southern right whale population dynamics and connectivity. It estimated total Australian population abundance, investigated links between whales using breeding areas along the eastern, southern and western coasts of Australia, and assessed future data collection needs for ongoing monitoring. The project supported evaluation of progress against the Conservation Management Plan for southern right whales and contributed to more coordinated conservation planning for the species at regional and national scales.