The Australian Defence Force has operated and trained in the Great Barrier Reef region for more than 100 years.
Training activities are undertaken in a few designated areas of the Reef, covering less than four per cent of the Great Barrier Reef Marine Park.
While most of these areas are small, the Townsville Star and the Shoalwater Bay Defence Training Area near Rockhampton are two of Australia's largest defence training areas. Other field training areas are located at Halifax Bay and Cowley Beach.
Training areas are regularly used by the Australian Defence Force and occasionally by other countries for land and sea-based exercises.
Activities include navy clearance dive training, boating and navigation exercises, and amphibious landings.
The Australian Department of Defence directly manages all defence training activities.
It also manages the environmental impacts within the Marine Park in collaboration with the Great Barrier Reef Marine Park Authority, the Australian Department of the Environment and Queensland government agencies.
The Great Barrier Reef Marine Park Zoning Plan provides for use and entry for defence activities without permission after notification to the Great Barrier Reef Marine Park Authority. These activities are subject to any directions from the agency.
Defence activities are well planned and well resourced, so incidents causing harm to the habitats and species in the region are rare.
High impact activities are confined to specific localised areas and limited to a few weeks per year.
Many defence activities are conducted with dedicated shipboard and aerial observers who can collect data on marine wildlife sightings, and ensure activities are delayed if required.
The Department of Defence has a moratorium on the use of high explosives in the Great Barrier Reef World Heritage Area except in the Shoalwater Bay training area.