Profile
In flight
Seabirds
Masked Booby
Sula dactylatra
- epic
- 85 km/h
- Least Concern
The largest booby. Lays two eggs but raises one chick, the older sibling evicts the younger within days.
- Population
- Global population not precisely quantified; described as fairly common but suspected declining (BirdLife 2018 assessment)
- Habitat
- Strictly marine and pelagic; forages over deep open ocean farther offshore than other boobies, coming ashore only to nest in large colonies on remote tropical islands, atolls, and cays (or rocky cliff ledges)
- Fun fact
- The Masked Booby is the largest of the booby species, and its two-egg clutch almost always yields only one surviving chick because the older, stronger nestling typically kills its younger sibling within days of hatching (obligate siblicide).
- Range
- Pantropical, found across the Indian, Pacific, and Atlantic Oceans roughly between 30°N and 30°S; absent from the eastern Atlantic, northern Indian Ocean, and central-eastern Pacific (replaced there by the Nazca Booby)
- Diet
- Fish (especially flying fish, up to ~28 cm) and squid, caught by high-speed plunge-diving from heights of roughly 12-100 m
- Size
- 0.8 m
- Wingspan
- 1.65 m
- Lifespan
- 25 years
