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  • A comparison was made of sediments and associated macrobenthos at sites sampled within 42 fish farm leases distributed across Tasmania. Several key biotic and abiotic metrics recommended in previous studies for assessing environmental impacts of fish farm waste were investigated.

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    This dataset consists of data collected by the real-time dissolved oxygen (DO) monitoring system in Macquarie Harbour, Tasmania, originally established under the Sense-T program, continued under FRDC project 2016-067 and deployed and maintained by IMAS. The system consists of 3 strings of acoustically telemetered, optical fluorescence DO, temperature and depth sensors (VEMCO, Bedford, Canada) which measure DO in % saturation, temperature in °C and depth in meters. The dataset spanning the time period from the 1st of January 2017 to the 19th of April 2017 consists of data collected using the first generation of sensors as described above. Subsequent quarterly updates from the 3rd of June 2017 onwards consist of data collected using the new generation of tags which contain a tilt instead of a depth sensor.

  • The goal of our study was to split the Australian maritime Exclusive Economic Zone (EEZ) into a set of smaller acoustic zones, whereby each zone is characterised by a set of environmental parameters that vary more across than within zones. The environmental parameters chosen reflect the hydroacoustic (e.g., water column sound speed profile), geoacoustic (e.g., sound speeds and absorption coefficients for compressional and shear waves), and bathymetric (i.e., seafloor depth and slope) parameters that directly affect the way in which sound propagates. Mean zone parameters and shape files are available for download. The zones may be used to map, for example, underwater sound from commercial shipping within the entire Australian EEZ.

  • The phenotypic plasticity of habitat-forming seaweeds was investigated with a transplant experiment in which juvenile Ecklonia radiata and Phyllospora comosa were transplanted from NSW (warm conditions) to Tasmania (cool conditions) and monitored for four months. We used multiple performance indicators (growth, photosynthetic characteristics, pigment content, chemical composition, stable isotopes, nucleic acids) to assess the ecophysiology of seaweeds before and following transplantation between February 2012 and June 2012.

  • Shifts from productive kelp beds to impoverished sea urchin barrens occur globally and represent a wholesale change to the ecology of sub-tidal temperate reefs. Although the theory of shifts between alternative stable states is well advanced, there are few field studies detailing the dynamics of these kinds of transitions. In this study, sea urchin herbivory (a ‘top-down’ driver of ecosystems) was manipulated over 12 months to estimate (1) the sea urchin density at which kelp beds collapse to sea urchin barrens, and (2) the minimum sea urchin density required to maintain urchin barrens on experimental reefs in the urbanised Port Phillip Bay, Australia. In parallel, the role of one of the ‘bottom-up’ drivers of ecosystem structure was examined by (3) manipulating local nutrient levels and thus attempting to alter primary production on the experimental reefs. It was found that densities of 8 or more urchins m-2 (≥ 427 g m-2 biomass) lead to complete overgrazing of kelp beds while kelp bed recovery occurred when densities were reduced to ≤ 4 urchins m-2 (≤ 213 g m-2 biomass). This experiment provided further insight into the dynamics of transition between urchin barrens and kelp beds by exploring possible tipping-points which in this system can be found between 4 and 8 urchins m-2 (213 and 427 g m-2 respectively). Local enhancement of nutrient loading did not change the urchin density required for overgrazing or kelp bed recovery, as algal growth was not affected by nutrient enhancement.

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    These data were collected on the RV L'Astrolabe (platform code: FHZI) from 21/10/2003 to 26/10/2003 on a trip from Hobart to Dumont d'Urville. Maximum photochemical efficiency of photosystem II (PSII), also called maximum quantum yield of PSII (Fv/Fm), has become one of the most widely utilized fluorescence parameters in phytoplankton research. It represents the potential photochemical efficiency, which is the probability that the light energy captured by the photosynthetic apparatus is being utilized as photochemistry. Fv/Fm has been shown to have an instant response to variations in physical and chemical properties and is interpreted as a diagnostic of the overall health or competence of phytoplankton. Together with the absorption cross section area of PSII and chlorophyll concentration, it can be used to measure primary production (Cheah et al. 2011, Deep Sea Research). Seawater from 3 m depth was supplied continuously from the ship’s clean seawater line. FRR fluorescence yields were measured continuously at 1 minute intervals in dark-adapted state (! 15 minutes dark-adaptation) using a flash sequence consisting of a series of 100 subsaturation flashlets (1.1 μs flash duration and 2.8 μs interflash period) and a series of 20 relaxation flashlets (1.1 μs flash duration and 51.6 μs interflash period).

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    These data were collected on the RV L'Astrolabe (platform code: FHZI) from 22/10/2006 to 25/10/2006 on a trip from Hobart to Dumont D'Urville. Maximum photochemical efficiency of photosystem II (PSII), also called maximum quantum yield of PSII (Fv/Fm), has become one of the most widely utilized fluorescence parameters in phytoplankton research. It represents the potential photochemical efficiency, which is the probability that the light energy captured by the photosynthetic apparatus is being utilized as photochemistry. Fv/Fm has been shown to have an instant response to variations in physical and chemical properties and is interpreted as a diagnostic of the overall health or competence of phytoplankton. Together with the absorption cross section area of PSII and chlorophyll concentration, it can be used to measure primary production (Cheah et al. 2011, Deep Sea Research). Seawater from 3 m depth was supplied continuously from the ship’s clean seawater line. FRR fluorescence yields were measured continuously at 1 minute intervals in dark-adapted state (! 15 minutes dark-adaptation) using a flash sequence consisting of a series of 100 subsaturation flashlets (1.1 μs flash duration and 2.8 μs interflash period) and a series of 20 relaxation flashlets (1.1 μs flash duration and 51.6 μs interflash period).

  • Projects including exploratory trawl surveys of the shelf and slope waters off southern Australia, targeted studies of specific fisheries, e.g. trawl fisheries for blue grenadier and orange roughy, purse seine fishery for jack mackerel, gillnet fishery for blue warehou, the coastal reef fishery for live fish fishery, inshore shark fishery, along with commercial catch sampling (on board and market sampling) have yielded an extensive dataset that includes biological, distribution and abundance information for a diverse range of finfish species from South East Australia. These data have been compiled into a single database and cover collections made between the late 1970s and mid 1990s. Note, selected data for key species (e.g. banded morwong, bastard and striped trumpeter) have been extracted and uploaded into Access databases (refer to scalefish research database, post mid-1990s).

  • Redmap is a primarily a website that invites the community to spot, log and map marine species that are uncommon in their region, or along particular parts of their coast. The information collected is mapped and displayed on the site, demonstrating, in time, how species distributions may be changing. Sightings are divided into two categories – those with a photo that can be ‘verified’ by a marine biologist, and sightings without photos that we call community sightings (anecdotal). All the information collected, with and without photos, is mapped and will be used in the following years to map out a ‘story’ of changes occurring in our marine environment. The main data collected includes the species sighted (normally selected from a list comprising preselected species of interest), the location, date/time and activity being undertaken. Other optional information gathered include biological data such as sex, size and weight and environmental data such as water depth and temperature and habitat. This record is associated with live data (and will subsequently change over time) and spatial elements have reduced accuracy. It is also subject to a three year embargo (ie. does not contain data less than three years old). If you wish to discuss obtaining a citable, static dataset, that is current and/or contains accurate spatial elements, please see Point of Contact.

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    These data are from a voyage (IN2019_V01) on RV Investigator with the Australian Antarctic Division (AAD), that took place during January-March 2019. The Chief Scientist was Mike Double from the AAD. Clara R. Vives collected biogeochemical data on the voyage, and performed a series of incubation experiments for her PhD. The purpose of the study was to investigate the effects of iron and light on phytoplankton growth off East Antarcitca. Data include CTD nutrients, chlorophyll and oxygen as well as underway phytoplankton physiology (measured as the photochemical efficiency) and pCO2. Some data are duplicated but not in exactly the same format on the CSIRO Data Trawler.