>>Are you implying that coconuts migrate?<<
If I am reading the article correctly, they do. They fall off the trees, are even swept off the trees in hurricanes and the like, into the ocean where they float from place to place (the map shows the migration path).
They are very hardy.
They are not hardy in that sense. The “eyes” of the coconut quickly soak up seawater and that kills the seed. They can float long distances by sea but they won’t arrive alive.