This tern was photographed over the continental shelf off Port Fairy, Victoria, Australia on 3rd July 2005. After considerable investigation by the observers and input from a number of experts on tern moult and plumages I am reasonably confident that this is an Antarctic Tern. This is potentially the first live record for mainland Australia. I would be especially interested in any flight shots of immature Antarctic Terns that might further assist in fully resolving the identification.