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    We implemented a monitoring program developed by Crawford and White (2006), which was designed to assess the current condition of six key estuaries in NW Tasmania: Port Sorell, the Leven, Inglis, Black, Montagu and Arthur River estuaries. This study considered a range of water quality and ecological indictors commonly used to monitor estuaries. These included: salinity, temperature, dissolved oxygen, turbidity, pH, nutrients (nitrate + nitrite, dissolved reactive phosphorus and ammonia), silica molybdate reactive and chlorophyll a for the water column; chlorophyll a and macroinvertebrate community structure amongst the sediments.

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    The data is the percent algal cover derived from underwater visual census methods involving transect counts at rocky reef sites around Tasmania. This data forms part of a larger dataset that also surveyed fish and megafaunal invertebrate abundance for the area. The aggregated dataset allows examination of changes in Tasmanian shallow reef floral and faunal communities over a decadal scale - initial surveys were conducted in 1992-1995, and again at the same sites in 2006-2007. There are plans for ongoing surveys. An additional component was added in the latter study - a boat ramp study looking at the proximity of boat ramps and their effects of fishing. We analysed underwater visual census data on fishes and macroinvertebrates (abalone and rock lobsters) at 133 shallow rocky reef sites around Tasmania that ranged from 0.6 - 131 km from the nearest boat ramp. These sites were not all the same as those used for the comparison of 1994 and 2006 reef communities. The subset of 133 sites examined in this component consisted of only those sites that were characterized by the two major algal (kelp) types (laminarian or fucoid dominated). Sites with atypical algal assemblages were omitted from the 196 sites surveyed in 2006. This study aimed to examine reef community data for changes at the community level, changes in species richness and introduced species populations, and changes that may have resulted from ocean warming and fishing. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. The underwater visual census (UVC) methodology used to survey rocky reef communities was designed to maximise detection of (i) changes in population numbers and size-structure (ii) cascading ecosystem effects associated with disturbances such as fishing, (iii) long term change and variability in reef assemblages.

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    The data is the quantitative abundance of megafaunal invertebrates derived from underwater visual census methods involving transect counts at rocky reef sites around Tasmania. This data forms part of a larger dataset that also surveyed fish abundance and algal cover for the area. The aggregated dataset allows examination of changes in Tasmanian shallow reef floral and faunal communities over a decadal scale - initial surveys were conducted in 1992-1995, and again at the same sites in 2006-2007. There are plans for ongoing surveys. An additional component was added in the latter study - a boat ramp study looking at the proximity of boat ramps and their effects of fishing. We analysed underwater visual census data on fishes and macroinvertebrates (abalone and rock lobsters) at 133 shallow rocky reef sites around Tasmania that ranged from 0.6 - 131 km from the nearest boat ramp. These sites were not all the same as those used for the comparison of 1994 and 2006 reef communities. The subset of 133 sites examined in this component consisted of only those sites that were characterized by the two major algal (kelp) types (laminarian or fucoid dominated). Sites with atypical algal assemblages were omitted from the 196 sites surveyed in 2006. This study aimed to examine reef community data for changes at the community level, changes in species richness and introduced species populations, and changes that may have resulted from ocean warming and fishing. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. The underwater visual census (UVC) methodology used to survey rocky reef communities was designed to maximise detection of (i) changes in population numbers and size-structure (ii) cascading ecosystem effects associated with disturbances such as fishing, (iii) long term change and variability in reef assemblages.

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    The data is the quantitative abundance of fish derived from underwater visual census methods involving transect counts at rocky reef sites around Tasmania. This data forms part of a larger dataset that also surveyed megafaunal invertebrate abundance and algal cover for the area. The aggregated dataset allows examination of changes in Tasmanian shallow reef floral and faunal communities over a decadal scale - initial surveys were conducted in 1992-1995, and again at the same sites in 2006-2007. There are plans for ongoing surveys. An additional component was added in the latter study - a boat ramp study looking at the proximity of boat ramps and their effects of fishing. We analysed underwater visual census data on fishes and macroinvertebrates (abalone and rock lobsters) at 133 shallow rocky reef sites around Tasmania that ranged from 0.6 - 131 km from the nearest boat ramp. These sites were not all the same as those used for the comparison of 1994 and 2006 reef communities. The subset of 133 sites examined in this component consisted of only those sites that were characterized by the two major algal (kelp) types (laminarian or fucoid dominated). Sites with atypical algal assemblages were omitted from the 196 sites surveyed in 2006. This study aimed to examine reef community data for changes at the community level, changes in species richness and introduced species populations, and changes that may have resulted from ocean warming and fishing. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. The underwater visual census (UVC) methodology used to survey rocky reef communities was designed to maximise detection of (i) changes in population numbers and size-structure (ii) cascading ecosystem effects associated with disturbances such as fishing, (iii) long term change and variability in reef assemblages.

  • This global meta-analysis documents data from underwater visual surveys used to determine the effect of kelp bed disturbance and canopy density on the abundance and structure of fish communities. Spatial, temporal and ontogenetic variability of many key fish species was examined at various levels of kelp disturbance at sites spanning a global temperate distribution. Rocky reef habitats and fisheries management regimes of sites were also examined as covariates. This data spans from 1984 to present. Note that Emma has completely fabricated this abstract, and requires direct input from KEEN.

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    Fixed position oxygen and water temperature logger data from the Macquarie Harbour World Heritage Area (WHA). Two Hobo oxygen data loggers are positioned at approximately 15 m depth at different sites within the WHA, with the intent of monitoring representative mid-bottom water oxygen values in the WHA as these were identified in previous studies to be naturally low due to limited seawater exchange at the harbour entrance, and thus likely to be most susceptible to anthropogenic factors that may increase oxygen demand and alter WHA conservation values. These values include core habitat of the Maugean Skate, a listed threatened species. This work is funded by WHA advisory board via the Nature Conservation Branch of DPIPWE and is part of a larger study being conducted by IMAS undertaking a biological baseline study of the biodiversity of the Macquarie Harbour WHA. This data spans 08/11/14 to present (most recent update 02/02/17).

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    Water quality and biological data was collected from four tide-dominated river estuaries indicative of catchments with varying levels of human impacts to: 1) assess draft indicator levels for water quality, and 2) investigate biological indicators of estuarine health in NW Tasmania. This data includes sampling from Detention River, Duck Bay, Montagu River and Black River

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    Physical and chemical parameters at five Pacific oyster (Crassostrea gigas) growing areas in Tasmania - Pittwater, Pipeclay Lagoon, Little Swanport, Georges Bay and Simpsons Bay - were measured as part of a study to determine the carrying capacity of the areas for oyster farming. This has provided valuable environmental data for these areas. The hydrodynamic regimes at each area except Simpsons Bay were studied, including high and low water volumes, flushing rates, flow rates and depth contours. Temperature, salinity and concentrations of nitrates, phosphates, silicates and chlorophyll a were measured monthly at several sites in each area. The change in these parameters over different time scales also was examined at two sites in Pittwater and indicated temporal and spatial variability in the environmental parameters measured.

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    Seasonal patterns in the in situ ecophysiology of the common habitat-forming seaweeds Ecklonia radiata, Phyllospora comosa, and Macrocystis pyrifera were investigated at different latitudes and depths in southeastern Australia. We used multiple performance indicators (photosynthetic characteristics, pigment content, chemical composition, stable isotopes, nucleic acids) to assess the ecophysiology of seaweeds near the northern and southern margins of their range, along a depth gradient (E. radiata only), over a two year period (September 2010 – August 2012).

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    A comprehensive and detailed multibeam sonar-based map of the shelf-break region of the Central Flinders Commonwealth Marine Reserve (CMR). It illustrates the extent that several canyon-head incisions are present in this region, and that inset from the shelf-break is a relatively extensive area of cross-shelf reef. Some of the canyon-head incisions are characterised by exposed reef areas, and these are indicated by localised regions of rapid change in depth. The cross-shelf reef is generally very low profile, but characterised by distinct reef ledges where bedding planes in the sedimentary rock types have eroded. These ledges, often between 1-2 m in height, can run for several kilometres as distinct features. The method of data extraction is based on Lucieer (2013). Three are three classes of seafloor map- one from GEOBIA, one from digitisation and one from Probability of Hardness based on Angular Profile Correction. Lucieer, V (2013) NERP broad-scale analysis of multibeam acoustic data from the Flinders Commonwealth Marine Reserve, Prepared for the National Environmental Research Program. Internal report. IMAS, Hobart, TAS [Contract Report]