White-tailed Tropicbird

Phaethon lepturus dorotheae / Koa‘e ‘ula
White-tailed tropicbird

Adult birds have mostly white plumage with long, white tail streamers. Tail feathers are visible while the bird is in flight as compared to the koa‘e ‘ula. Black eye-stripe from gape curving toward and passing through eye. Diagonal black stripe across upper wings. Yellowish to orange bill. Legs/feet are yellowish with black webs.

Typically solitary feeders though sometimes seen in pairs. With folded wings, koa‘e kea hit the water and completely submerge to seize and swallow prey before flight. 

Courting birds fly in parallel, with streamers from bird above turned downward toward mate. Fly together in shallow glides. Begin nesting at 4 years of age. Nesting habitat is coastal cliffs, primarily in a scratched out hollow with a cliff crevice. Nest year round with peak activity from March through October. At Kīlauea Point, birds nest in cavities of tree limbs, root bases of ironwood trees and/or other secluded spots.

A single egg is laid and incubated (40-42 days) by both adults. Lacks brood patch. Average incubation shift lengths range from about 4-8 days. Chicks are tightly brooded for the few days after hatching. Unlike other Pelican relatives, adults regurgitate food by putting their bills down the gaping chick's throat. Average chick fledge times vary between 10-12 weeks.

Facts About White-tailed Tropicbird

Diet
Typically solitary feeders though sometimes seen in pairs. With folded wings, white-tails hit the water and completely submerge to seize and swallow prey before flight. Prey consists of fish and squid. 

Life Span
16 years 

Size
Length: 38-40 cm (15-16 in), 71-81 cm (28-32 in) including tail streamers; wingspan: 89-94 cm (35-38 in)