The Hawaiian petrel or ''uau'' (''Pterodroma sandwichensis'') is a large, dark grey-brown and white

petrel Petrels are tube-nosed seabirds in the phylogenetic order Procellariiformes. Description Petrels are a monophyletic group of marine seabirds, sharing a characteristic of a nostril arrangement that results in the name "tubenoses". Petrels enco ...

that is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

Distribution

The Hawaiian petrel was formerly found on all the main

Hawaiian Islands The Hawaiian Islands () are an archipelago of eight major volcanic islands, several atolls, and numerous smaller islets in the Pacific Ocean, North Pacific Ocean, extending some from the Hawaii (island), island of Hawaii in the south to nort ...

except

Niihau Niihau (Hawaiian language, Hawaiian: ), anglicized as Niihau ( ), is the seventh largest island in Hawaii and the westernmost of the main islands. It is southwest of Kauai, Kauai across the Channels of the Hawaiian Islands#Kaulakahi Channel, Ka ...

, but today it is mostly restricted to

Haleakalā Haleakalā (; Hawaiian: ), or the East Maui Volcano, is a massive, active shield volcano that forms more than 75% of the Hawaiian Islands, Hawaiian Island of Maui. The western 25% of the island is formed by another volcano, Mauna Kahalawai, als ...

crater on

Maui Maui (; Hawaiian language, Hawaiian: ) is the second largest island in the Hawaiian archipelago, at 727.2 square miles (1,883 km2). It is the List of islands of the United States by area, 17th-largest in the United States. Maui is one of ...

; smaller populations exist on

Mauna Loa Mauna Loa (, ; ) is one of five volcanoes that form the Island of Hawaii in the U.S. state of Hawaii in the Pacific Ocean. Mauna Loa is Earth's largest active volcano by both mass and volume. It was historically considered to be the largest ...

on the island of

Waimea Canyon Waimea Canyon, also known as the Grand Canyon of the Pacific, is a large canyon, approximately long and up to deep, located on the western side of Kauai in the Hawaiian Islands of the United States. Waimea is Hawaiian for "reddish water", a ...

on the island of

Kauai Kauai (), anglicized as Kauai ( or ), is one of the main Hawaiian Islands. It has an area of 562.3 square miles (1,456.4 km2), making it the fourth-largest of the islands and the 21st-largest island in the United States. Kauai lies 73 m ...

, Lānaihale on Lānai, and possibly

Molokai Molokai or Molokai ( or ; Molokaʻi dialect: Morotaʻi ) is the fifth most populated of the eight major islands that make up the Hawaiian Islands archipelago in the middle of the Pacific Ocean. It is 38 by 10 miles (61 by 16 km) at its g ...

. It was formerly lumped together with a very similar species from the Galapagos Islands. In 2013 a specimen was retrieved from Arizona near the Colorado River, marking the first inland North America record of this species. On August 7, 2023, a Hawaiian petrel was reported near Cape Arago, proximate to

Coos County, Oregon Coos County ( ) is one of the Oregon counties, 36 counties in the U.S. state of Oregon. As of the 2020 United States census, 2020 census, the population was 64,929. The county seat is Coquille, Oregon, Coquille. The county was formed from the ...

. It is not the first record of the species in the state, and there are also reports of it from California.

Behavior

Feeding

Their diet consists of 50–75%

squid A squid (: squid) is a mollusc with an elongated soft body, large eyes, eight cephalopod limb, arms, and two tentacles in the orders Myopsida, Oegopsida, and Bathyteuthida (though many other molluscs within the broader Neocoleoidea are also ...

, and smaller percentages of

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

and

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

Breeding

These birds nest in burrows or rock crevices. Their breeding season extends from March to October. The female lays one white egg. When the chick hatches, the parents go out to sea and feed during the day, and return only at night. They pass their food on to the chicks by means of regurgitation. The chicks are charcoal-gray colored and were considered a delicacy by early Hawaiians. Scientists previously thought that the petrels remained relatively close to shore during the breeding season. New research employing microwave

telemetry Telemetry is the in situ collection of measurements or other data at remote points and their automatic transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Greek roots ''tele'', 'far off', an ...

shows that the birds travel as far as

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

and

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

during two-week-long feeding trips. When returning to nest burrows at night, adults make a distinctive moaning "oo-ah-oo". At their burrows, adult birds also make a variety of yaps, barks, and squeals. The petrel's flight is characterized by high, steeply banked arcs and glides. Their wings are long and narrow with a wingspan of . The wings and tail are sooty-colored. Their feet are bicolored pink and black.

Status and conservation

The Hawaiian petrel is an endangered species. In addition to loss of habitat from development, the greatest threats to the petrel are

feral cat A feral cat or a stray cat is an unowned domestic cat (''Felis catus'') that lives outdoors and avoids human contact; it does not allow itself to be handled or touched, and usually remains hidden from humans. Feral cats may breed over dozens ...

small Asian mongoose Small Asian mongoose is a common name applied to two mammals which were formerly considered to be a single species: * Javan mongoose * Small Indian mongoose Mammal common names {{Short pages monitor *(2005). ''Hawaii's Birds''. Hawaii Audubon Society. Sixth ed.

External links

*BirdLife International. (2024). Species factsheet: ''Pterodroma sandwichensis''. Downloaded fro
BLI Datazone
on Nov. 3, 2024. *Oikonos. (September 2007). New Project: The Mystery of the Uau

* {{Taxonbar, from=Q524533 Pterodroma Biota of Kauai Biota of Maui Endemic birds of Hawaii Birds described in 1884 ESA endangered species Taxa named by Robert Ridgway