Black-vented Shearwater

How to find it

Costa Rica's seabird work has been small. Stiles and Smith surveyed the Gulf of Papagayo in the 1970s and the Gulf of Nicoya into the early 1980s, and a research project from the University of Costa Rica now studies seabirds in the country's ocean waters. Recent extra effort to search for pelagic species has turned up first records of several shearwaters, including this one. Offshore Pacific trips are the logical places to look. Because it does not follow ships or come to chum, scanning the water carefully matters more than baiting.

How to recognise it

This is a small shearwater, 30 to 38 cm long, with a wingspan of 76 to 89 cm.

Look for these marks:

- Upperparts blackish brown.

- Underparts and wing linings white.

- A dark trailing edge on the underwing.

- A black bill and pink feet.

- A dark undertail, which gives the bird its name and stands out sharply against the clean white underside.

The head and throat look dingier than on its closest lookalike, which helps when the light is good.

Behaviour and diet

It flies low over the waves with a fluttery flight and fast wingbeats. It takes small fish and crustaceans from the sea surface and sometimes dives for them, from the surface or from just above it, reaching depths of over 20 m.

It is not drawn to chum and does not usually follow ships, so it will not come to a boat the way some seabirds do.

Where it lives

It is an open ocean seabird, though it forages closer to shore than many other pelagic species and tends to avoid long foraging trips. It stays nearer the coast than most shearwaters and is sometimes seen from land.

It breeds on islands off Baja California, especially Guadalupe, San Benito and Natividad. In Costa Rica it is a rare wanderer to Pacific waters, far from those islands. Survey work here has mostly covered the coasts and Isla del Coco National Park, so the offshore waters remain poorly known.

Similar birds

The Manx Shearwater is similar in size and flight but whiter below, especially under the base of the tail. The Black-vented is dingier around the head and throat. The Manx is the other small black-and-white shearwater on the Costa Rican list, also rated accidental, and the two are easily confused at sea. The Black-vented was long treated as a subspecies of the Manx. Its dark bill and legs also separate it from the pink-billed Pink-footed Shearwater.

Names and lore in Costa Rica

The official Costa Rican list uses Pardela Culinegra. Another Spanish name in general use is Pardela Mexicana. Some Costa Rican web lists misspell the first as Parcela Culinegra.

Status and conservation

The official Costa Rican list, updated June 2026, still gives it status A (accidental), and it is Near Threatened worldwide.