|MadSci Network: Zoology|
For hummingbirds in the US east of the Mississippi River their normal fall and spring migration routes include a long overwater leg once they get south of Florida. The eventual destination for these migrants is South America and islands in the southern Carribean. These migration routes also coincide with many popluar cruise ship routes. So it is not that unbelievable that a weary migrating hummingbird would find a perch on a passing ship during the bird's trip south. Those birds that do manage to find a ship equipped with a feeder would stand a greater chance of survivng the migration south and reproducing (provided their nesting habitat hasn't been developed out of existence).
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