well i see a few, probably 24-25 at noosa. sometimes i see a few at caloundra and moroochy. i know for a fact there are some over on the west coast.
so australia alone your probably looking at about 250 odd.
now mutiply that by 7 (number of continents).
thats 250 x 7 = 1850.
just remeber this is a rough guestimate. dont QFT.
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