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  • Out-of-range observations of significant rafts of giant kelp (Macrocystis pyrifera) washing ashore in southern NSW in winter 2020. On 9 August 2020, two local marine naturalists on the south coast of New South Wales, Australia noticed a significant amount of a large unfamiliar kelp washed up on a local beach. Following some quick confirmations via phone and email, it was revealed that the unfamiliar seaweed was giant kelp (Macrocystis pyrifera): a species whose closest known populations are ~450 km away to the south (in Tasmania and western Victoria) and whose transport to New South Wales would have required oceanic rafting over several weeks and hundreds of kilometres against the prevailing south-flowing East Australian Current. Subsequent community-led searches over the following days confirmed four more locations of often-substantial amounts of giant kelp wrack, as well as many more anecdotal and unconfirmed accounts.

  • This record provides an overview of the scope and research output of NESP Marine Biodiversity Hub project E7 - "Assessing the feasibility of restoring giant kelp beds in eastern Tasmania". For specific data outputs from this project, please see child records associated with this metadata. -------------------- This project will extend an externally funded project conducted through UTAS commencing in 2018 to select for thermally tolerant and low-nutrient-tolerant giant kelp (Macrocystis pyrifera) genotypes, and to examine effects of acclimation of selected genotypes by pre-exposure to warm, nutrient-poor conditions. The proposed project will outplant pre-exposed selected genotypes of giant kelp as micro-sporophytes in an experiment with and without provision of an added source of nutrient. The work is designed to assess the feasibility of this approach as a means to develop minimum patch sizes for giant kelp that can be self-replacing and self-expanding, thus providing restoration and future climate-proofing options for this EPBC-listed marine community. Planned Outputs • Experimental data from macrocystis restoration • Final report

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    An aerial survey was conducted for giant kelp (Macrocystis pyrifera) on the east coast of Tasmania from Eddystone Point to Southeast Cape. This survey represents part of a series of similar surveys, with historic aerial surveys having been conducted in 1986 and 1999. The survey was conducted via light aircraft. Areas of visable Macrocystis pyrifera beds were marked on topographical land tenure maps using landmarks as references, and complimentary photo footage was collected.

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    An aerial survey of giant kelp (Macrocystis pyrifera), was carried out on the east coast of Tasmania from Musselroe Bay to Southeast Cape. This survey represents part of a series of similar surveys, with historic aerial surveys having been conducted in 1986, 1999 and 2009. This survey was conducted via light aircraft in Nov-Dec 2019, and recorded areas of visible surface canopy cover of giant kelp. Canopy areas were scribed in-flight onto 1:50,000 topographic maps (TASMAP 2017), and complimentary photo and video footage was collected. Canopy areas were digitised with reference to photo, video and map data within QGIS 3.4, and boundaries were checked against Seamap Australia seafloor habitats (Lucieer et al. 2017) and bathymetric data (Smith 2016). Each bed was attributed a broad and fine scale location, density and reliability estimate (see attached report for details). This survey was completed with funding from Pennicott Wilderness Journeys, Tassal and IMAS, and equal in-kind support by Marine Solutions and Seacare Inc.

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    The main aim of this research program was to determine the potential for reducing the density of urchins to encourage the return of seaweeds and an improvement in urchin roe quality and quantity from remaining urchins. Tasmanian Sea Urchin Developments used two widely-separated sub-tidal experimental lease areas. One of these areas was at Meredith Point, on the east coast, and the other at Hope Island, on the south coast. Both sites had been subject to some overgrazing by urchins. At Meredith Point, the study area was divided into plots containing urchins at three densities: artificially enhanced, continually harvested and control (undisturbed). At Hope Island, controlled clearings of urchins and limpets from barrens areas were conducted. Recovery of vegetation was monitored as well as urchin roe quality and quantity. The data represented by this record was collected at Hope Island, and includes results from an inital survey collected at the site before the main study commenced.

  • This record provides an overview of the NESP Marine and Coastal Hub bridging study - "Future-proofing restoration & thermal physiology of kelp". For specific data outputs from this project, please see child records associated with this metadata. -------------------- For restoration to be effective, the cause of habitat decline must be understood and overcome. But this is problematic when climate change is driving habitat loss since it cannot be reversed or ameliorated prior to restoration. A previous NESP project led by this team (Project E7, Marine Biodiversity Hub) identified warmwater-tolerant strains of giant kelp from remnant patches in eastern Tasmania, where the species has experienced precipitous declines due to ocean-warming. These strains have high potential to assist with ‘future-proofing’ kelp forest restoration, however it is still unclear what the physiological mechanisms are that provide their improved thermal tolerance. This project is designed to better understand these physiological mechanisms to advance kelp restoration efforts in Australia and globally, and progress toward the identification of populations of Australian kelp that may be resilient to (or especially threatened by) ocean warming and climate change. Planned Outputs • Ecophysiological measurements from laboratory experiments of warm-tolerant vs average giant kelp genotypes [dataset] • Final technical report with analysed data, including a short summary of recommendations for policy makers of key findings [written]

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    This record describes an aggregated data product compiled from a number of different surveys of Macrocystis surface cover in Tasmanian waters, spanning 1950 to 2019. Some surveys represent a statewide census of Macrocystis cover, while others are targeted surveys of smaller regions. Methodology and data quality lso varies between surveys. Please see linked metadata records for specific methodologies and quality statements applying to individual surveys.

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    A project investigating the restoration of string kelp (Macrocystis pyrifera) habitat on Tasmania's east and south coasts. Macroalgae, fish and invertebrate counts were collected as part of the project using the Edgar Barrett transect technique in the Derwent Estuary and in the Mercury Passage on the South East Tasmania. Other fish, invertebrate and macroalgal data was also collected.

  • As a condition of licence for harvesting Macrocystis pyrifera (Linnaeus) C. Agardh 1820, Alginates (Australia) P/L lodged harvest returns to the Tasmanian Lands Department. The harvest returns consisted of what tonnage was harvested from where, when and the length of trip. While Alginates (Australia) P/L harvested from 1964-1973, harvest data for individual sites is only available for the years 1970-71. Here the data is summed for individual sites for the two years 1970-71.

  • A research program jointly conducted by Alginates (Australia) P/L and C.S.I.R.O. Division of Fisheries and Oceanography was set up to investigate the relationship between kelp: Macrocystis pyrifera (Linnaeus) C. Agardh 1820 and crayfish larvae. Alginates (Australia) P/L, based at Louisville in the Mercury Passage, were harvesting kelp at this time. This study was initiated to address concerns regarding the effect of harvesting on crayfish stocks. The survey results are taken from an unpublished interim report presenting the results of the work at that stage (1965). Apparently an aerial survey was used to determine stock distributions although this is not specified in the report.