by wifwendell
From 16.1, page 22:If the expedition survived any required Navigation roll, is carrying
a colony, and there is an unoccupied gray settlement space (other
than the Philippines) connected to this ocean zone, the active power
may place the colony from this expedition on the settlement. Once
placed, colonies may not be moved.
So basically, if a seacaptain carrying a colony survives and is in a place where he can do it, he can build a colony.