By the hundreds they've been treated and cared for at specialty rehabilitation centers.
But what happens to the sick or injured California brown pelicans once they're set free again? What are their chances for surviving back out in the wild?
Researchers are hoping an ongoing survey of the pelicans treated at California's bird rehabilitation centers will provide them with a better glimpse into how the birds fare - and where they go - once they are released.
"We've put a lot of time and money into these birds," said Jay Holcomb, director of the nonprofit International Bird Rescue that operates a facility in San Pedro. "We wanted to know if they're surviving."
Some of the California brown pelicans head north for the winter - not south like most other birds. Many have been found as far north as British Columbia, according to study results.
It was known that many of them fed along the Oregon and Washington coasts but that the young pelicans flew so far north so quickly after they were released was a surprise, Holcomb said.