Dubbing and filming locations

I just had a chance to watch this movie after reading about it for so many years and I have to say that, whilst it is so obviously a low budget Jaws knock-off, I did actually find it surprisingly watchable. Indeed, L'ultimo Squalo is actually far more enjoyable to watch than both the third and fourth movies in the Jaws series. It is so bad that it is actually quite good. There are two elements of the movie that I wanted to try find out more about.

The first one is the dubbing. I realize this was an Italian production and much of the cast and crew were Italian, so dubbing obviously came into play. I just wondered if anyone knew if the American actors were dubbed at all? It sounds like James Franciscus, Vic Morrow and Joshua Sinclair many not have been dubbed over but I just can't tell for sure. Morrow's accent in particular is quite comical to listen to and I just wonder if the US actors were dubbed over with other voices.

The other query I have is regarding filming locations, particularly the beach scenes, etc. It states on the IMDB entry that filming was completed in both Malta and Savannah, Georgia but I just wondered if the beach scenes were filmed in the US at all? Thanks for any info!