Hawaiian Shearwater

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Image:Hawaiian shearwater.JPG

Common Name: Hawaiian or Newell’s Shearwater
Scientific Name: Puffinus newelli

Size: 13 inches (33 cm); 76 cm wingspan

Habitat: Oceania; It breeds in at least 20 colonies on mountain slopes in the Hawaiian Islands. The main colonies are on Kauaʻi, on slopes around the Alakaʻi Plateau and probably in the Mokolea Mountains. Its distribution on the other islands is uncertain but it is known to breed on Molokaʻi and the island of Hawaiʻi and may breed on Oʻahu, Maui and Lānaʻi. From April to November it can be seen in the waters around the Hawaiian Islands, particularly around Kauaʻi. Outside the breeding season it disperses into the tropical Pacific Ocean. Its distribution at sea is little known but many move south and east into the waters of the Equatorial Counter Current. It has been recorded as far west as the Mariana Islands. In the south there are recorded sightings from Samoa in September 1977 and American Samoa in January 1993.

Status: Endangered. Global Population: 33,000 - 38,600 mature individuals and rapidly decreasing. On Kaua`i, hurricanes Iwa and Iniki devastated the forests in 1982 and 1992, and, since the latter, the species's population has been declining. Given that a large proportion of the population breeds on Kaua`i, catastrophic events, like hurricanes, are a serious threat. Subsequent and ongoing habitat modification by alien invasive plant species, such as strawberry guava Psidium cattleianum, and feral pigs and goats, pose a significant threat. This is likely to be a contributing factor at one known colony abandonment. The recent establishment of the two-spotted leafhopper Sophonia rufifascia, which feeds on D. linearis, could be a further problem. Predation (e.g. by cats, rats, dogs, Barn Owls Tyto alba and pigs) is an additional threat. Predation of adults and juveniles by cats has been documented on Kaua`i, and rats are assumed to take eggs and chicks. Another potential predator, the small Asian mongoose Herpestes javanicus, has recently been discovered on Kaua`i. An estimated 70 adults and 280 subadults each summer, and at least 340 fledglings each autumn, die as a result of collisions with power-lines and communications towers, or indirectly because of light attraction. Birds attracted by artificial lighting become exhausted and fall to the ground. Once on the ground, fledglings are unable to fly and many are killed by cars or cats and dogs, and some die from starvation or dehydration. Between 1978 and 1981, more than 5,000 individuals were grounded on Kaua`i, and over 30,000 have been recovered since 1979. On Kaua`i, approximately 1,500 fledglings are recovered annually after becoming grounded. Nine communications towers have recently been constructed on the Hawaiian islands without proper consultation, and these are now the subject of an ongoing lawsuit. A field of wind generators is planned for Lana`i, where the species potentially breeds, although this is thought to be unlikely. On Hawai`i, cinder mining has resulted in habitat loss at several colonies. The species may suffer indirect impacts from the over-fishing of tuna Thunnus species, which drive prey species to the ocean surface. This could have implications for the energetic costs of foraging, with potential impacts on chick growth and fledging success. Fledglings have been found with pox lesions, suggesting that disease may be affecting breeding populations.

Diet: Squid and small fish. It feeds far from land, in areas of deep water (at least 2000 meters). It dives into the water to catch its prey, swimming down to a depth of up to 10 meters using its wings to move forward. It is attracted to schools of tuna and gathers in flocks with other seabird species to catch prey driven to the surface by the tuna.

Breeding: The upper parts are black with a brown tinge while the under parts are white. The dark coloration on the face extends below the eye and is sharply separated from the white throat. There is a white patch on the flanks, extending onto the sides of the rump. The under wings are mainly white with a dark border. The under tail-coverts have a black and white pattern and appear white in the field. The bill is dark grey or brown and the legs and feet are mainly pale pink.

The nest site is a burrow dug into a steep slope, usually sheltered by uluhe (Dicranopteris linearis ferns). A single white egg is laid during the first two weeks of June. Both parents incubate the egg and an incubation period of 62 days has been recorded. The young birds leave the nest in October, 88-100 days after hatching. They fly out to sea and are no longer dependent on their parents.

Cool Facts: It is named after Brother Matthias Newell, a missionary who worked in Hawaii from 1886 to 1924. By 1908, it was thought to be extinct but was rediscovered in 1947 and found breeding on Kauaʻi in 1967. It is known in Hawaiian as the ʻaʻo.

The bird flies low over the water on stiff wings with a mixture of short glides and periods of rapid flapping.

Found in Songbird ReMix Seabirds Volume 2 and Songbird Remix Hawai'i

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