The Tasmanian Estuaries (South East) Marine Habitats 1:25,000 layer depicts marine habitats of nine estuaries (Bryans lagoon, Catamaran River, Cloudy Bay Lagoon, D'Entrecasteaux River, Great Swanport, Little Swanport, Pipeclay Lagoon, Pitt Water and Southport Lagoon) in the south east of Tasmania. The habitat types depicted in the dataset include rocky reef, sand, hard sand and seagrass. The data was collected from November 2004 to September 2005 by marine researchers at the Tasmanian Aquaculture and Fisheries Institute. The shallow waters of the estuaries enabled the use of aerial photography, including purpose flown aerial surveys, and satellite imagery as the primary data source. The habitats defined in the imagery were ground truthed in the field with underwater camera equipment, echo sounder data, and a Differential GPS unit. The dataset is intended for the use of fulfilling the coastal management objectives according to The Living Marine Resources Act 1995 and to support Natural Resource management priorities in the Southern NRM region of Tasmania.

Archival aerial photography data in the ILS, DPIWE library was assessed for currency and seafloor visibility. The most current images were selected, ranging from 2003 to 2004. No recent imagery was suitable for Cloudy Bay Lagoon and Southport Lagoon, so purpose-flown imagery was collected on 26th November 2004 by TAFI. Quickbird imagery from the Greater Hobart Project (copyright DigitalGlobe, courtesy of Sinclair Knight Merz) was used for Pitt Water. Selected aerial photographs were scanned at 600dpi and stored as 24bit colour TIFF images. Each was georeferenced using ESRI ArcGIS Version 9.0 to the Tasmanian Coastline coverage in GDA94 and mosaics created where required. The imagery data was used to interpret boundaries and formed the basis of a polygon coverage that was generated from the data. The point datasets that were collected in the field were checked for extraneous data, cleaned and converted to a point coverage using ESRI ArcGIS Version 9.0. The point data was overlaid on the aerial photographs to check for agreement. The generated polygon coverage was clipped to the 1:25,000 coastline shape. The 1:25,000 coastline was supplied by the Land Information Services Division of the Department of Primary Industry, Water and Environment Tasmania.

Position Accuracy: The positional accuracy of the GPS was found to vary 1.5m in the horizontal plane when left to record for a period of 60minutes. The aerial photography was georectified to within approximately 5-10 m for most locations. The Quickbird imagery has a specified error of 3 m for the Pitt Water area. Attribute Accuracy: The attributes assigned to the 1:25,000 Habitat Mapping Series were based on the interpretation of the aerial photography and the acoustic signal using EchoView 3.30 software (Sonar Data TM). These attributes were ground truthed with the sediment core samples, seagrass quadrat samples, field photographs and observations and underwater video information. Logical Consistency: All data has been checked for duplicate features, extraneous points, unclipped polygons and unattributed polygons by both visual and automated means. Completeness: The Tasmanian Estuaries (South East) Marine Habitats data set is complete for the listed estuaries for the entire area below the high water mark as defined by the LIST 1:25,000 coastline. Additional: http://www.utas.edu.au/tafi/seamap/