Pterodroma cervicalis: White-necked Petrel

White-necked Petrel - Pterodroma cervicalis
( Salvin, 1891 )

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Subspecies:	Unknown
Est. World Population:	100000

CITES Status:	NOT LISTED
IUCN Status:	Vulnerable
U.S. ESA Status:	NOT LISTED

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Top Speed:
Jumping Ability:	(Horizontal)

Life Span:	in the Wild
Life Span:	in Captivity

Sexual Maturity:	(Females)
Sexual Maturity:	(Males)
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Habitat:

On Macauley Island, White-necked Petrels nest in localised colonies, especially in Sandy Bay, on the slopes above Quadrat Gully, on the gully slopes and floor of Access Gully, on the plateau near Grand Canyon, in Jim’s Gully, and on the upper slopes of Mt Haszard. Although their burrows were once found on forested ridges on Raoul Island, all colonies on Macauley Island are under grass, sedges or fern (G. Taylor pers. comm. in Gaskin 2011). On Raoul, it nested below 300 m on high-altitude ridges (Marchant and Higgins 1990). Two birds were found on the northern terraces of the island (2005 and 2006) covered in the spiny burrs of a native grass (Cenchrus calyculatus) that prevented them from flying. These two birds were presumed prospecting birds and a return to breeding on this rugged island cannot be discounted. This species is also known (from at-sea observations) to be in the waters around Raoul Island in May (Gaskin 2011).
On Phillip Island, it is a summer breeder. Birds come ashore as early as 11 November, but lay eggs in January (Priddel et al. 2010). Birds nesting on Philip Island differ from the population on Macauley by nesting among boulders and in crevices in rocky habitat with sparse understorey, below a canopy of mature White Oaks Lagunaria patersonia that provide concealment from avian predators (Priddel et al. 2010). It has also been known to nest in artificial cavities. On Phillip Island, the only known nests are at the top of Long Valley, but other areas have potential nest sites (Priddel et al. 2010). It feeds mainly on squid (Heather and Robertson 1997). Little is known of the breeding biology.

Range:

Pterodroma cervicalis breeds on Macauley Island in the Kermadec Islands, New Zealand (c.50,000 pairs in 1988), with a second small colony recently established on Phillip Island, off Norfolk Island (to Australia) with nests increasing from six in 1994 to 20 in 2005 (Priddel et al. 2010). It bred on Raoul Island, also in the Kermadec Islands, early in the 20th century (Taylor 2000). Two birds were found on Raoul Island in 2005 and 2006 covered in seed-burrs, possibly prospecting (Gaskin 2011). It migrates to the tropical and sub-tropical north Pacific Ocean (Spear et al. 1992) with recent sightings in Hawaiian waters (eBird) .

The rare sub-species occulta breeds in small numbers on Vanua Lava, Vanuatu (Totterman 2009). In February 2010, it was photographed 60 miles from the site of the original specimens, constituting only the second documented sighting since 1927; a total of 21 individuals were sighted over a three-day period, nine seen rafting before dusk (P. Harrison in litt. 2010).

Conservation:

Conservation Actions Underway

Goats were removed from Raoul and Macauley in 1984 and 1970, respectively. The eradication of rabbits from Phillip Island in 1985 may have resulted in the species colonising the island in the following years. Polynesian rats were eradicated from Macauley in 2006 and cats and rats were eradicated from Raoul Island between 2002 and 2006 (G. Taylor in litt. 2012). Two birds found on Raoul Island covered in seed burrs in 2005 and 2006 were presumed prospecting birds. Since 2007, automated sound attraction units have been installed on Raoul Island in an attempt to lure the species. However, there has been no evidence so far that this has worked, although breeding on this rugged island cannot be discounted as searches in promising gully areas have not occurred (C. Gaskin in litt. 2016). A study area on Macauley was established in 1988 (G. Taylor in litt. 1999). The Kermadec Islands are nature reserves with access by permit only. Extensive searches were conducted for incubating birds of this species in the upper reaches of Long Valley, the main water catchment of Phillip Island (N. Carlile in litt. 2012).

Conservation Actions Proposed

Map populations on Macauley Island and complete a census. Monitor Macauley every five years to ensure that no establishment of predators has occurred. Monitor the recovery of vegetation on Macauley and any negative effects on the species. Recapture birds in study area to determine data on survival and longevity every five years (Taylor 2000). On Raoul conduct monitoring of acoustic attraction sites where White-necked Petrel calls are broadcast, using playback and spotlights to check for birds flying over land (Northern Terraces) during summer months, and also conduct ground searches of ridges and slopes at western end of island (towards Hutchison Bluff) (C. Gaskin in litt 2016). Survey Vanua Lava and assess threats.