Australian maritime archaeologists have returned to the location of a 19th-century sailing ship that is in danger of being wrecked due to recent seabed changes that are alarmingly revealing the site.

The package South Australian site has been visited again by the Australian National Maritime Museum (ANMM) and the nonprofit Silentworld Foundation to complete survey work and collect crucial data that could help us better comprehend early colonization and occupancy.

Since 1820, the sailing vessel has been a mail carrier between England and remote outposts of the British Empire. Its original name was Marquess of Salisbury. Later, it was used as HMP Swallow, a British naval packet. The South Australian Company bought it and renamed it South Australian.

Australia's earliest known wreck is a ship that went down in Encounter Bay, close to modern-day Victor Harbor, in 1837. It was missed by two surveys in the 1990s, and it was only found again in 2018. Due to its historical significance, archaeologists have continued to show a strong interest in it ever since. The ship, which is thought to have carried about 80 immigrants to the new colony, was built to carry a significant amount of sail on a very tiny hull for optimal speed.

On December 8, 1837, the ship's demise occurred. When it was smashed by a southeasterly storm, it was carrying whale oil and getting ready to leave for Hobart. None of the participants died.

While a sizeable portion of the remaining hull is still hidden, according to ANNM, recent seabed changes are alarmingly exposing the site. This has made it even more urgent to conduct additional research.

However, subsequent trips to the site were halted for two years because to Covid-19 travel restrictions. When archaeologists came back to their work last year, they were able to complete site mapping and photogrammetric 3D recording. The crew also carried out a thorough conservation evaluation to ascertain the state of preservation of the wreck site and recommend methods for its ongoing care.

Work at the site has included careful recording of exposed hull components and targeted retrieval of at-risk artifacts during the present expedition. A modest number of items have also been found and mapped. A cannon flint, ceramic pieces with designs, ship fasteners, glass bottles, and a whetstone for sharpening tools are among the objects.

It is impossible to overestimate the historical and archaeological importance of South Australia. "It has the potential to improve our understanding of the state's initial colonization and occupation, including the establishment of extractive mercantile activities like shore-based whaling and interactions between European colonists and Aboriginal people," said James Hunter, ANMM's Curator of Naval Heritage and Archaeology. As South Australia's oldest recorded European shipwreck and one of its earliest immigration vessels.

While late last year's attempts to perform 3D photogrammetric scans of the wreck were hampered by the weather and water visibility, imagery from those surveys is now being used to create a computerized 3D model of the majority of the site. This year, the crew aims to finish the photogrammetric survey of the wreck.

The government of South Australia claims that a total of 126 vessels have gone missing in the inland and coastal seas of the area, resulting in the loss of at least 28 people and 11,500 tonnes of cargo.