Here's a link for anyone interested. Its Radar based and not AIS, this means Royal Naval vessels are visable in and out of Portsmouth.
Its updated every couple of minutes. All vessels with red boxes are bulk flammable carriers such as LPG Gas, Petrol, Crude Oil. These are frequest visitors to the massive Fawley oil refinery on Southampton Water.
http://www.southamptonvts.co.uk/radcap.asp (http://www.southamptonvts.co.uk/radcap.asp)