Identifying whether a frigate bird is baby, juvenile or adult is reasonably easy. A baby is white and fluffy, a juvenile is black with a white head, a male adult is black with a red chest and a female adult is black with a white chest. The wing span of an adult frigate is usually six to seven feet.
To attract females, the males will puff up their red throats (they are called gular) with air by clicking their throats. They throw back their heads while doing it. It is extraordinary to watch them. I have noticed that they never fly with their chests fully inflated, the most they fly with is about a quarter of the full and it still looks like a struggle for them.
Once hatched, it takes about five to six months for the babies to learn to fly and by then they will have developed a partially black body. Once two years old the frigate bird is an adult and they have now developed a red (or white) chest and full jet black body.
Frigate birds from this sanctuary have flown as far north as Florida with tagged ones, and have gone as far south as Venezuela. These amazing birds have flown so far it is almost unbelievable.