Bulwer's petrel

Bulweria bulwerii

Photo by Martin Lofgren (Wild Bird Gallery)

Common name:
Bulwer's petrel (en); alma-negra (pt); pétrel de Bulwer (fr); petrel de Bulwer (es); Bulwersturmvogel (de)


Taxonomy:
Order Procellariiformes
Family Procellariidae


Range:
The Bulwer's petrel is a pantropical species, being found in the tropical and sub-tropical areas of the Atlantic, Indian and Pacific oceans. Breeding sites include the eastern Atlantic from the Azores, Portugal to Cape Verde, and the Pacific from eastern China and the Bonin Islands, Japan, east to the Hawaii and the Marquesas Islands of French Polynesia.


Size:
These birds are 25-29 cm long and have a wingspan of 70-90 cm. They weigh 80-130 g.


Habitat:
They are marine and highly pelagic, usually being found far from land foraging in warm oceanic waters. They breed in small rocky islands.


Diet:
The Bulwer's petrel mainly feeds on mesopelagic prey, particularly luminescent species such as myctophid and sternoptychid fishes and squids such as Pyroteuthis margaritifera. They also eat planktonic life forms. They mostly forage at night, when these deep sea species visit the surface of the sea.


Breeding:
In the Atlantic they breed in April-October. They are colonial, nesting in natural burrows, crevices, cracks or caves, under debris or vegetation cover, usually about 1 m deep. There the female lays 1 egg which is incubated by both parents for 42-46 days. The chicks are fed by both parents and fledge 60-65 days after hatching. Each pair raises a single chicks per year.


Conservation:
IUCN status - LC (Least Concern)
The Bulwer's petrel has a relatively large breeding range and a global population estimated at 500.000-1.000.000 individuals. The population is suspected to be stable in the absence of evidence for any declines or substantial threats.