
Photo: Matteo Bellucci · CC BY 4.0 (May be cropped or resized)
Phaethon aethereus
Diet
Fish and squid
Habitat
Tropical oceans; nests on cliff faces
Range
Tropical Atlantic, eastern Pacific and Indian Oceans
Clutch size
1 egg
Incubation period
About 6 weeks
Size
90–105cm including tail streamers
Wingspan
99–106cm
The red-billed tropicbird is a tern-like seabird, 90–105cm long including tail streamers of 46–56cm, or about 48cm without them, with a wingspan of 99–106cm. It is white with black wing-tips, a finely black-barred back and a black mask running from the lores to the sides of the nape, and has a red bill. Males are generally larger with longer streamers. The subspecies indicus of the Middle East and Indian Ocean is smaller, with a more restricted mask and a more orange bill (Wikipedia, general species account).
It is one of three closely related tropicbirds of tropical oceans. It nests in loose colonies, choosing a scrape on a cliff face from which it can easily take off, and lays a single egg that both parents incubate for about six weeks. Birds of all ages feed on fish and squid. It has the smallest range of the three tropicbirds, across the tropical Atlantic, eastern Pacific and Indian Oceans. SoIB 2023 lists it as a winter visitor to Indian waters but gives no trend or priority (Wikipedia, general species account; SoIB 2023).