Abalone fishing block 27 - High resolution acoustic data of reef habitat

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique. This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management. Data for download has been split by fishing block (22-24, 27-30). This record describes *FISHING BLOCK 27*. The following data products are available for download, for each fishing block: • 50cm resolution bathymetry • 50cm resolution substrate type (Seamap Australia classification) • bathymetry derivatives (seabed slope, curvature, rugosity, 1 and 2m contours) • water column data - 1m mean signal • water column data - 9m2 raw block statistic • water column data - vegetation likelihood classification See associated records for access to data from other fishing blocks (22, 23, 24, 28, 29, 30).

Abalone fishing block 23 - High resolution acoustic data of reef habitat

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique. This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management. Data for download has been split by fishing block (22-24, 27-30). This record describes *FISHING BLOCK 23*. The following data products are available for download, for each fishing block: • 50cm resolution bathymetry • 50cm resolution substrate type (Seamap Australia classification) • bathymetry derivatives (seabed slope, curvature, rugosity, 1 and 2m contours) • water column data - 1m mean signal • water column data - 9m2 raw block statistic • water column data - vegetation likelihood classification See associated records for access to data from other fishing blocks (22, 24, 27, 28, 29, 30).

Thermal performance curves for Lessonia corrugata

Kelps are in global decline due to climate change, including ocean warming. To identify vulnerable species, we need to identify their tolerances to increasing temperatures and whether tolerances are altered by co-occurring drivers such as inorganic nutrient levels. This is particularly important for those with restricted distributions, which may already be experiencing thermal stress. To identify thermal tolerance of the range restricted kelp Lessonia corrugata, we conducted a laboratory experiment on juvenile sporophytes to measure performance (growth, photosynthesis) across its thermal range (4 – 22 °C). We found the upper thermal limit for growth and photosynthesis to be ~ 22 – 23 °C, with an optimum of ~ 16 °C. To determine if elevated inorganic nitrogen availability could enhance thermal tolerance, we compared performance of juveniles under low (4.5 µmol/day) and high (90 µmol/day) nitrate conditions at and above the thermal optimum (16 – 23.5 °C). Nitrate enrichment did not enhance thermal performance at temperatures above the optimum but did lead to elevated growth rates at the thermal optimum 16 °C. Our findings indicate L. corrugata is likely to be extremely susceptible to moderate ocean warming and marine heatwaves. Peak sea surface temperatures during summer in eastern and northeastern Tasmania can reach up to 20 – 21 °C and climate projections suggest that L. corrugata’s thermal limit will be regularly exceeded by 2050 as south-eastern Australia is a global ocean-warming hotspot. By identifying the upper thermal limit of L. corrugata we have taken a critical step in predicting the future of the species in a warming climate.

Abalone fishing block 24 - High resolution acoustic data of reef habitat

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique. This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management. Data for download has been split by fishing block (22-24, 27-30). This record describes *FISHING BLOCK 24*. The following data products are available for download, for each fishing block: • 50cm resolution bathymetry • 50cm resolution substrate type (Seamap Australia classification) • bathymetry derivatives (seabed slope, curvature, rugosity, 1 and 2m contours) • water column data - 1m mean signal • water column data - 9m2 raw block statistic • water column data - vegetation likelihood classification See associated records for access to data from other fishing blocks (22, 23, 27, 28, 29, 30).

High resolution acoustic data of reef habitat - Tasmanian East Coast

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique. This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management. All spatial datasets and derivatives of the have been uploaded onto the Seamap Australia data portal for visualisation as a resource for both managers and scientists for further analysis and study. Data packages have been split by fishing block (22-24, 27-30) and are available to download from each of the 'child' records linked to this record (below).

Abalone fishing block 28 - High resolution acoustic data of reef habitat

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique. This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management. Data for download has been split by fishing block (22-24, 27-30). This record describes *FISHING BLOCK 28*. The following data products are available for download, for each fishing block: • 50cm resolution bathymetry • 50cm resolution substrate type (Seamap Australia classification) • bathymetry derivatives (seabed slope, curvature, rugosity, 1 and 2m contours) • water column data - 1m mean signal • water column data - 9m2 raw block statistic • water column data - vegetation likelihood classification See associated records for access to data from other fishing blocks (22, 23, 24, 27, 29, 30).

Abalone fishing block 29 - High resolution acoustic data of reef habitat

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique. This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management. Data for download has been split by fishing block (22-24, 27-30). This record describes *FISHING BLOCK 29*. The following data products are available for download, for each fishing block: • 50cm resolution bathymetry • 50cm resolution substrate type (Seamap Australia classification) • bathymetry derivatives (seabed slope, curvature, rugosity, 1 and 2m contours) • water column data - 1m mean signal • water column data - 9m2 raw block statistic • water column data - vegetation likelihood classification See associated records for access to data from other fishing blocks (22, 23, 24, 27, 28, 30).

Abalone fishing block 22 - High resolution acoustic data of reef habitat

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique. This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management. Data for download has been split by fishing block (22-24, 27-30). This record describes *FISHING BLOCK 22*. The following data products are available for download, for each fishing block: • 50cm resolution bathymetry • 50cm resolution substrate type (Seamap Australia classification) • bathymetry derivatives (seabed slope, curvature, rugosity, 1 and 2m contours) • water column data - 1m mean signal • water column data - 9m2 raw block statistic • water column data - vegetation likelihood classification See associated records for access to data from other fishing blocks (23, 24, 27, 28, 29, 30).

Abalone fishing block 30 - High resolution acoustic data of reef habitat

The principle aim of this project was to map the fine-scale spatial distribution of key abalone habitat impacted by urchins in < 25 m water depth using multibeam acoustic imagery. Detailed substrate type (Pavement Reef, Megaclast Reef, Mixed Consolidated Sediment/Reef and Sand), and kelp coverage maps have been produced for the east coast of Tasmania. Large urchin barrens have been predicted and the minimum quantifiable unit of which small incipient barrens can be detected has been identified using this acoustic water column technique. This data provides a snapshot of the 2021 distribution of seafloor habitats and associated vegetation distribution, and will assist in the facilitation of strategic decision making for urchin control and abalone management. Data for download has been split by fishing block (22-24, 27-30). This record describes *FISHING BLOCK 30*. The following data products are available for download, for each fishing block: • 50cm resolution bathymetry • 50cm resolution substrate type (Seamap Australia classification) • bathymetry derivatives (seabed slope, curvature, rugosity, 1 and 2m contours) • water column data - 1m mean signal • water column data - 9m2 raw block statistic • water column data - vegetation likelihood classification See associated records for access to data from other fishing blocks (22, 23, 24, 27, 28, 29).

Condition of rocky reef communities around Tasmania: fish surveys

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.

EARTH SCIENCE | BIOSPHERE | ECOSYSTEMS | MARINE ECOSYSTEMS | REEF