Downloadable through Google Earth, the mapping shows reefs and other seabed formations, and provides information about wrecks and marine life.
Linked photographs and texts provide support through a format of layers.
Divers can identify sites of potential interest and note GPS co-ordinates for dive outings.
The mapping extends from Abbotsbury to Swanage, and to a maximum of six miles offshore.
It is the result of the Dorset Integrated Seabed (DORIS) project, run by the Dorset Wildlife Trust, Maritime and Coastguard Agency and Channel Coastal Observatory.
It has used multibeam sonar surveys, information from Seasearch and other research groups, photographs taken by divers or remote cameras, and information from grab samples.
A £300,000 biodiversity grant was made available for the work by Viridor Credits, a supporter of environmental and community-based projects, through the Landfill Communities Fund.
Its value to sport divers apart, the mapping was conceived to improve knowledge of marine habitats, timely given a new era of marine management kick-started by the Marine and Coastal Access Act 2009.
The mapping will be of use to Finding Sanctuary, the South West representative for researching Marine Conservation Zones under the Act; and to C-SCoPE, run by the Dorset Coast Forum to assess marine plans at county level.
The information will also be useful to sea industries scientists and engineers, organisers of coastal defences, and for the updating of mariners’ charts.
The DORIS team intends to extend coverage over the next two years to the whole of Lyme Bay and eastward to the Isle of Wight’s Needles. It would welcome help from divers.
“Divers can help us greatly by joining Seasearch as research volunteers,” Peter Tinsley, Marine Conservation Officer at the Dorset Wildlife Trust, told Divernet. “We co-ordinate Seasearch programmes for Dorset.”
Divers who independently gather information or photographs of notable seabed features, wrecks or marine life at positions which can be accurately identified can also make contact.
They should call Tinsley on 01305 264620 or email him at ptinsley@dorsetwildlifetrust.org.uk.
It is possible, said Tinsley, that the work could be copied for other parts of the country, as the benefits of the DORIS project become clear to marine research and management groups.
The MCA, he added, would almost certainly come in as a partner as it looks to gather data for further marine chart updates by Taunton’s RN Hydrographic Department.
To download DORIS mapping, first obtain the freely downloadable Google Earth programme, then run the URL http://tinyurl.com/dorismap.
Related links
Seasearch with Dorset Wildlife Trust
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