Family: The red-tailed tropicbird (Phaethon rubricauda) is a stunning marvel of skies and belongs to the family Phaethontidae.
Diet: The red-tailed tropicbird is a lovely bird that lives in the Indo-Pacific tropical and subtropical seas, feeding on squid and fish. As it looks for them, either alone or in couples, it flutters its wings and alternates between soaring glides. It swoops, dives onto its victim from heights of up to 14 meters, and frequently submerges for approximately 25 seconds. The majority of its food, however, comes from the water’s surface, where rough serrations on its bill keep prey in place.
Behavior and Habitat: Adult tropicbirds pair for life and breed at customary nest locations every 12 months or so. Shaded places on cliff edges keep the brooding bird cool (tropicbirds cannot cool themselves by fanning their throats) and let the birds come and go easily; to go, they just fall off into the air. Tropical birds are nearly incapable of landing on land due to their weak, fully webbed feet. A bird relieving its spouse at the nest cries as it approaches, hovers overhead, and then lands to greet its partner with the most cursory of bill-touching.
Nest locations are protected from competitors by battling alone. The warriors stare one another down, then grapple with their bills, spreading wings and feet for balance and purchase. Daily aerial displays by courting birds are breathtaking. Calling pairs or groups of pairs circle the nesting site. Once a single, followed by its partner, swoops up and backpedals on quickly flapping wings before flying away. Their tail streamers undulate downward and upward, and their feet are stretched to each side. These flights may continue even after the eggs are laid. Mating occurs back in the nest.
Mated birds share incubation in daily shifts, which typically change about midday. Chicks hatch covered in down and are brooded continuously for the first few days, but after about a week, both parents return briefly to feed them once a day. In response to the chick’s repeated strident rattling, the feeding parent approaches and is lunged at.
The adult inserts its beak into the chick’s esophagus and turns its head sideways, regurgitating partially digested fish–the opposite of how boobies, cormorants, and allies feed. The baby bird is fully feathered by 40 days and weighs more than adults, but it does not fledge for another four to five weeks. Departure is quick, and the fledgling simply flops from the nest into the sea or air and flaps away, never to return or be visited by its parents again.
Identification: Both adults are similar. General plumage is white with black stripes through the eye, on the innermost flight feathers, and on the flanks. The rosy sheen of varying intensity on body plumage. Two long, red central tail feathers with black shafts. The eyes are dark brown. The bill is red with a black line along his nostrils. The feet are pale blue; the webs and toes are black. The immature birds have black bars on the upperparts and no streamers. The downy young is silky grey-fawn from hatching; his bill and feet are black.
Vocalizations: Red-tailed Tropicbird’s main call is a ratchet-like pirr-igh in courtship flight. The bird sound is loud, defensive screaming at Nest.
Alternative Names: Red-tailed Bos’n-bird, and Silver Bosun-bird.
Size: Red-tailed Tropicbird size is about 460–470 mm in length, excluding 300–530 mm tail-streamers.
Nesting: A round Australia breeds mainly over summer in the subtropics and overwinter in the tropics. Solitary or in loose groups, each nest 20–30 m apart. Nest a scrape in the ground, in the shade of a bush, or under the rocky overhang on the side of a cliff. Some nests are inside caves.
Eggs: Red-tailed Tropicbird lays one egg, sometimes two; color variable-dark spots on a light grey-brown or white base; long-oval, size varies—about 64 x 45 mm in northwestern Australia and 68 x 47 mm in the Tasman Sea. The incubation process is 42–50 days, for both sexes. Young fledge in 4 to 5 weeks.
Distribution: Red-tailed Tropicbird is found in tropical and subtropical waters of the Indian and western Pacific Oceans. More common along the northern than southern shores of Australia. Nests on cliffs and islands of western, northern, and northeastern shores.
Races: There are four subspecies, two in Australia: one smaller and whiter off the west coast and the other rose-tinted and larger off the east.