Do I need a licence to operate a Marine VHF radio?
The Marine Radio Short Range Certificate remains a legal requirement for the use of marine VHF. All radios require the user and the vessel to hold a relevant licence. The vessel's licence is like a car tax disc, but is also the key to obtaining an MMSI number, which will uniquely identify your vessel. The user requires a radio 'driving licence' and two different types are available.
For VHF only, the SRC (Short Range Certificate) instructs users in radio etiquette and procedures. VHF operation itself is fairly straightforward; however, the course also teaches you about digital selective calling (DSC) functions and emergency procedures.
Source:
http://www.icomuk.co.uk/Choosing-a-VHF-Marine-radio