Red-billed Tropicbird

How to find it

Look for it on offshore boat trips, since it is a pelagic seabird. The sea route to Isla del Coco is the best documented, and all but one sighting in a seabird survey came on voyages to and from the island. A pelagic trip from Quepos heading south toward Caño Island recorded two at different times and places. The Puntarenas to Paquera ferry crossing takes about an hour and a half, and one writer called a sighting there a matter of low odds. A survey noted that low decks close to the water helped detect small pelagic birds. Keep scanning every pale seabird, because one birder took it for a Royal Tern until it came close.

How to recognise it

Adults are mostly white with a black-barred back. Look for these marks:

- a broad black stripe from eye to nape

- black outer wing feathers

- a red bill

- long, flowing central tail feathers

Young birds look different. The bill is yellowish and the black barring is heavier, reaching the nape. The tail feathers have black tips and none is elongated, so the streaming tail of an adult is missing. Adults are in the minority in Costa Rican waters: of 12 birds seen by researchers, only 2 were adults.

Behaviour and diet

It flies gracefully over open sea, gliding and circling with quick wingbeats that look more like a pigeon's than a tern's. In courtship it also makes long glides with the tail feathers bent downward.

It feeds mainly by plunge-diving, and flying fish are its preferred food, sometimes caught in mid-air. Away from breeding colonies it is usually alone or in pairs, and researchers in Costa Rican waters always saw single birds. It rests on the water with its tail held half-raised.

Where it lives

This is a pelagic bird of open ocean. In Costa Rica it is seen well offshore on the Pacific side, and researchers saw it regularly in those waters. It forages over open ocean, often where upwelling brings reliable prey.

Costa Rican sources give no nesting data. The nearest breeding sites are islands off Mexico, Colombia and the Galápagos, and a small nesting colony lives on Swan Cay in western Bocas del Toro, Panama.

When to see it

It probably occurs off the Pacific coast all year round. A seabird survey saw it in both seasonal transitions, dry to wet and wet to dry, though its authors made no July sightings.

Similar birds

Next to the White-tailed Tropicbird, it is easy to separate by its mottled black and white back and deep red bill. It lacks that species' black wing stripe and has more black on the wingtip. Royal Tern is sometimes mistaken for a tropicbird.

Names and lore in Costa Rica

The official Spanish name in Costa Rica is Rabijunco Piquirrojo. Elsewhere the species is also called Rabijunco Etéreo and Rabijunco Pico Rojo.

Status and conservation

The official Costa Rican bird list gives it status M, and its global conservation status is Least Concern.

Photography tips

Sightings in Costa Rica are well offshore and usually of single birds, so expect brief, distant views. A seabird survey noted that low decks close to the water helped detect small pelagic birds. Good light on a close bird shows the black back barring, the black eye line and the thick reddish bill.