Thank god for that, just did a search for my ship and now know where I am
Oddly though, it has our status as moored/anchored, but the transponder is set to Restricted in manoeuverability. I had to double check when I looked at the marine traffic site.
Search for vessel Maersk Tackler
I listened in on a radio conversation between Bristol VTS and an incoming ship. After the usual reporting in, VTS told the ship that he wasn't showing up on AIS. The skipper or watch leader showed a severe bout of disinterest and advised that he wasn't a technocrat. A moment later VTS came back to say that they had checked marinetraffic.com and that showed the same ship in Gibraltar. Still not much of a response from the ship so VTS said they would have to report the matter.
When I got home a couple of hours later I looked up the ship on marinetraffic.com and it was shown in Royal Portbury Dock. The vessels track was only about 5 or 6 miles long and started just about in the position the ship was when I heard the radio conversation.
So..... AIS is very interesting, could be useful at times, but don't assume that a thumping great 184m LOA car transporter will have it switched on.