CSIRO researchers at the World Heritage listed Ningaloo reef make a surprise discovery of a ship's anchor that may be up to 150 years old while mapping the ocean's floor.
As part of a four-and-a-half-year research project, scientists are using an autonomous underwater vehicle (AUV) to help create the most detailed maps of Ningaloo reef on record, particularly in the deeper, less-explored areas.
On the first day of testing the AUV last week, the team discovered the anchor a few hundred metres offshore, in the lagoon. "It is the most amazing thing ... that evening when we were looking at some of the footage ... and there it was, a really old-school 19th century anchor that you would expect to see on an admiralty sailing ship," CSRIO research lead Russ Babcock said.
The next day, after using the AUV data to pinpoint its location, divers went down for a closer inspection.
"At first, we didn't believe it was a proper, old-time anchor, I thought it must be from someone's tinny," Dr Babcock said. "We had to do a double take" "It was just like on SpongeBob SquarePants."
Based on advice from the WA Museum, the anchor is estimated to be between 100 to 150 years old and from an old coastal trading ship. It has not been linked to any particular shipwreck."This is the type of place an Australian coastal trading ship would pick up and drop off goods," Dr Babcock said. "Possibly they had to cut [it] off because it was stuck or they needed to get out of there because of a storm."
Dr Babcock said as there wasn't a visible chain, it is hard to ascertain any further information about the anchor without disturbing it.
After surveying four kilometres of the reef, it is the only manmade artefact the researchers found apart from bits of fishing line.
The data is being used to generate habitat maps of the area, to understand exactly how the environment influences the distribution of coral and fish.