How does a huge, lumbering bird like the Great White Pelican fly halfway around the world to reach a place like Florida?

Great White Pelican lands on Merritt Island Refuge/Photos by Anders Gyllenhaal
It’s a question birders and experts alike have been asking in the weeks since one of these striking, exotic pelicans from Africa and Asia arrived on the Merritt Island Wildlife Refuge south of Jacksonville. Although birds are always turning up in unexpected places, this visit set off a true kerfuffle as word got around.
Our Flying Lessons post on the Great White Pelican drew thousands of views and 600 shares on our Facebook page. With those came an avalanche of questions:
Did this bird fly all the way – or perhaps escape from a zoo in this hemisphere? Will it stay in the area, or find its way back home? Will it upset the balance of nature the way certain non-native plants and animals do? How does a bird get so far off course in the first place?
“I would love to know what his story is,’’ Linda Boccuti wrote on our Flying Lessons Facebook page.
Most of the answers are guesses, since the bird wasn’t tagged and certainly isn’t talking. But Andrew Farnsworth, a research associate with the Cornell Lab of Ornithology who specializes in migration, said the likely drivers are genetic migration instincts that go off track, lack of food back home and changing weather patterns that are becoming more frequent around the globe.