Christmas Shearwater

How to find it

Plan a boat trip offshore, because this is not a bird for land birding. Seabirds are poorly studied in Costa Rica, and records come mostly from the coast and from Isla del Coco National Park.

A Quepos pelagic trip left at 1:45 am and went about 50 nautical miles south toward Caño Island, with shearwaters and boobies active as soon as light came. Watch for mixed feeding flocks over tuna schools, which this bird tends to join.

A birding blogger lists it among the real chances for rarities on a Costa Rica pelagic day, and describes the Puntarenas to Paquera ferry as the easiest way to see some pelagic birds. Be patient, because dark shearwaters at sea are hard to identify with distance and boat motion.

How to recognise it

This is a slim, medium-sized shearwater, about 36 cm long, with a wingspan near 75 cm.

Look for these marks:

- Plumage dark all over, blackish-grey with a rusty-brown tinge, a little paler below.

- Underwings dark brown, though they can look silvery in some light.

- A short tail that tapers to a point in flight.

- Feet that stick out past the tail tip.

- Dark legs, not pale pink.

It is smaller than the Sooty, Short-tailed and Wedge-tailed Shearwaters. Against the Sooty and Short-tailed it has a relatively longer tail and a fully dark underwing.

Behaviour and diet

It eats fish and squid, taken at or near the surface. It dives after prey but does not go very deep. Squid, goatfish and flying fish are key prey in Hawaii and on Christmas Island.

It tends to join mixed feeding flocks that gather over schools of large predatory fish such as tuna, which push prey to the surface. In flight it usually stays low over the water, with stiff, fast wingbeats and little soaring.

Where it lives

It breeds in colonies on remote tropical Pacific islands and atolls, nesting in the open on the surface. It spends the rest of its time over the open ocean.

Outside the breeding season, birds spread east into the eastern tropical Pacific. They have been recorded off Mexico, Guatemala and Costa Rica, and south to Peru and Chile. In Costa Rica the records are from offshore waters of the Pacific coast, including Puntarenas and the Osa Peninsula, and from Cocos Island, where it is listed as rare or accidental.

When to see it

No regular season is known. Photos offshore date from April 2017 and March 2019, and one shore sighting on the Puntarenas coast was in June.

Similar birds

It looks much like the Sooty and Short-tailed Shearwaters, but it is smaller, with dark brown underwings. Next to the Wedge-tailed Shearwater, which is regular off Costa Rica, its tail is short and rounded, not long and wedge-shaped.

Off Malpais, guides chased two small dark shearwaters hoping for Christmas Shearwaters. They proved to be Galapagos Shearwaters, a small bicolored species expected offshore in Costa Rica.

Names and lore in Costa Rica

The official Spanish name is Pardela de Navidad. A Costa Rican bird list also gives Pardela de Christmas as an alternate name. A news report on the first national record used pardela de pascua, and other Spanish names found for it include Pardela Pardo and Pardela de Isla Navidad.

Status and conservation

The official Costa Rican list (AOCR, updated June 2026) marks it as A, accidental or very rare, and it is not a resident or an endemic.

Photography tips

On a Malpais pelagic trip, two Christmas Shearwaters had been seen the previous week leaving a big feeding flock. Watch the edges of big feeding flocks for dark shearwaters flying away from them. Distance and boat motion make identification hard, so take photos where you can and check them afterwards against the tail shape, feet and underwing.