I am dual English/Australian citizen and my wife is dual Canadian/Australian and we were gettinga bit concerned as we planned our
circumnavigation as it appeared that dual nationals got a hard deal on
import duties.
Australian
Customs told us that as we were Citizens of
Australia we would have to pay
import duty as soon as we set foot in
Australia even though the
boat is UK registered and we only plan to stay for a few months. I had read on the board here that Canadians can similarly get slugged as they are not allowed to sail a foreign flagged vessel in Canadian waters.
I did some follow up
research as I didn't want to have to pay 3 import duty 3 times!
There is good news in the form of the UN Treaty called the International
Customs Convention On Tourism which protects the rights of people touring. Under this you are exepmt from paying import duty on your vessel if you are a tourist, which boils down to not being ordinarily resident in that country.
I subsequently rang back Australian Customs who grudgingly admitted that as long as we weren't ordinarily resident they couldn't charge us duty even though we own passports from Australia.
Canada and The UK are also signatories to the treaty.
Obviously we still have to see how this works in practice, but if anyone wants to charge you import duty for a short stay refer them to this and they may change their mind.