Location: from Houston, TX; currently berthed in Barcelona, headed west
Boat: Amel SM 53 - BeBe
My experience is they like to sit on the pulpit, especially while at anchor. We tied 1 or 2 small black plastic trash bags to the pulpit...worked!
I also heard of someone feeding them bread pieces followed by a piece of dry ice. They swallowed the dry ice, expecting bread. In a short time they exploded. Still have to clean up, but only once per bird.
before i got bubba i had seagulls -- they took keys --didnt even use em--just to toss into sea--
-the addition of tarps on boat topsides helped a lot also as the tarp flutters it scares off the birds--frigate birds especially dislike tars--they like to hunt from mastheads--the tarps scare and distract them.