Eastern Central Pacific (B) (NB), French Polynesia, USA (B).
Vagrant to Indonesia, Japan, Philippines.
Hawaiian Is.
 
Population
Estimated population is 9,000 - 16,600 (2010) and decreasing.
Status EN
Predation by introduced cats, Common Barn-owl (Tyto alba), rats, dogs, pigs and the small Asian mongoose Herpestes javanicus and habitat degradation by goats, pigs and cattle and invasive plants and the main threats.
For more information see BirdLife International Species Factsheet.
Habits
Usually forages in mixed species flocks.
Food
Mainly fish and squid.
Voice
A low-pitched, gurgling 'goo-oooo-gouih-gouih-gooo-o'. While flying in pairs, one bird may utter 'u-u-u', and the other will follow immediately with a rapid 'ch-ch-ch'.
Hawaiian Petrel (Pterodroma sandwichensis) [XC75584]
by Thomas G. Graves from Paliku Camp, Haleakala N. P., Maui, Hawaii, USA, United States (call)
Hawaiian Petrel (Pterodroma sandwichensis) [XC328234]
by UCSC CCAL from Leleiwi Overlook, Haleakal\u0101 National Park, Maui County, Hawaii, United States (call, flight call)
Nest
In lava cavities with little vegetation nearby, or amongst dense shrubs and ferns, or in native grasslands with bracken, or in rock crevices and tunnels that are over 0.5 m deep.
Subspecies
Considered by some authors as a subspecies of Galapagos Petrel (Pterodroma phaeopygia).
No subspecies.
Similar Species
Compared to Juan Fernandez Petrel (Pterodroma externa) and White-necked Petrel (Pterodroma cervicalis) darker, with more extensive cap, darker back, lacking "M", and different underwing. Compared to Galapagos Petrel (Pterodroma phaeopygia) lacks black forehead markings.
References
See References.