At a guess the vessel details and the photographs are stored separately on the site's server, with a link between them. The link will somehow have become corrupted, and is not being made. Same thing can happen on your own PC, if you put in a link from one file to another, then rename one of the files, the link won't work. I suspect someone has been doing some work on the site, and accidentially broken the link. It's probably a quick fix once someone looks at it.