apparently, Kiritimati has 37 species of birds and
the Masked Booby Sula dactylatra is one of the 20 species which
breeds there. The male and female are similar in appearance, form
a monogamous relationship, produce 2 chalky white eggs, and share
the incubation (approx 43 days).
The chick's leg or wing is just visible in this photo.
Check out how much it has grown in two weeks in the next photo.