I've never been to the bit of Brittas Bay south of Mizen Head, but I've been to a fair few naturist beaches around the continent, and as he says what the OP reports is hardly a unique problem. Generally the 'meerkat' problem is worse close to urban areas (which in terms of access Brittas is), and in countries where the native population is quite conservative in matters of nudity (check).
For example, one of the worst incidences I've seen was at the nudist beach at the southern end of oh-so-crappy Faliraki, Rhodes - thus close to a built up area, and in Greece (where locals tend to dress and act conservatively, and generally leave nudist beaches to the tourists). There was a rotating population of voyeurs and public fiddlers hanging around in the scrubby slope overlooking the beach. In countries like France where locals are as likely to be on a nudist beach as furriners, or in Germany/Austria where locals considerably outnumber tourists, it never seems to be much of a problem. Spain seems to fall somewhere in the middle.
So it strikes me that the 'demand' side of the problem mainly comes down to familiar cultural confusion over the difference between sex and nudity, and the fact that this is pretty much the only well-known nudist beach in Ireland concentrates the problem. If this is the only place a weirdo can go to see real life nekkid folks, then this is where a weirdo will go.
Where the situation seems to differ from even the worst European example is that of policing. Every time I have seen a hint of a problem like this on a continental nude beach (including Faliraki), there has been an immediate response from the users. One or more people (usually large fat men) have marched right up to the trouble makers and asked them to leave, with universal success. This often extends to camera use amongst otherwise normal users too. It may sometimes be undertaken by deckchair rental guys or cantina operators, but it is usually just regular beach users, and never the cops*. Your average pervert is already confused enough, the sight of cross-looking naked men approaching him is almost always too much.
So without any direct experience, I suspect the problem is a lack of numbers and sense of community amongst the regular users - hard to generate with a small user base and so few suitable days in the year! It seems a shame to suggest it, but unless you're prepared to take these feckers to task,its probably best to avoid the place - at least until regular use increases to the point that there is a beach 'community' (which may never happen). As matters stand, it sounds like the weirdoes outnumber the nudists, so some strong deterrence is called for. But I wouldn't bother invoking the law.
*When cops get involved with nudist beaches, it's usually to suppress swinging/dogging/cottaging activities, which is a separate issue altogether, and hopefully not one Brittas Bay has to deal with.
Last edited by Tordelback; 19-07-2010 at 15:23.