Twanger said:
Culebra Customs is 877-529-6840. You cannot reach them from a mooring at Bayo Tortugas because you won't have cell coverage there. You can get cell coverage from about 4 miles out.
We've been scolded for calling before we are anchored. We do SVRS, so the process is a bit different for us. You need a current DTOPS sticker on your boat or you'll need to go to the airport and buy one.
Cheers, RickG