I have no idea who Jimmy Buffett is (although I guess he's not related to Warren).
I wonder how much of the recent increase in the island's population is indeed from the community of paradise-seeking expatriates, and how much has come from the mainland and the surrounding region.
We might perceive that every new arrival is a developed-world citizen seeking an island lifestyle to retire with. But it may be that most are local economic migrants who came looking for work and opportunities based on (yes) an erstwhile boom in construction and tourism, then brought their families - and have stayed.
It will be interesting to see the census results - if they include this sort of data.
(Also I wonder how the impact on the environment caused by population growth varies with these sorts of factors.)