EN
Polynesian Storm-petrel Nesofregetta fuliginosa



Justification

Justification of Red List Category
This species is classified as Endangered as it has a very small and fragmented population which is continuing to decline. It is clear that invasive species are the primary reason for this decline, and although eradication at some locations has been conducted and further eradication programmes are planned for the future, this species remains highly threatened.

Population justification
The current known population may be as low as c.1,000-1,600 mature individuals, equivalent to c.1,500-2,400 individuals in total. However given that some surveys date back to the mid-1990s, and significant declines have been observed in previous strongholds, it is possible that the population may be lower than this. It is clear that data is lacking and a comprehensive survey needs to be conducted to assess the true population size.

Trend justification
Repeated estimates since the 1960s have indicated population declines of >50% on Kiritimati (=Christmas Island), a key breeding colony. Trend data from other colonies is lacking, but there may have been local extinctions, and the species appears not to coexist with rats and cats (Brooke 2004). However, there are attempts to breed on islets infested with Polynesian rat Rattus exulans, probably supplemented by recruits from adjacent rat-free islets (R. Pierce in litt. 2007).

Distribution and population

Nesofregetta fuliginosa breeds in the Line and Phoenix Islands (Kiribati), Austral, Society (formerly Tahiti), Gambier and Marquesas Islands (French Polynesia), New Caledonia (to France) (3-4 pairs in 1996-1997 [V. Bretagnolle in litt. 1999], although repeated visits in 2007 failed to produce any records pointing to local extinction [J. Baudat-Franceschi in litt. 2007], but since sighted twice off the northern tip and may possibly breed on atolls off the northern end of the island [C. Collins in litt. 2011]), Sala y Gomez (Chile) (100 pairs in 1997 [Vilina and Gazitua 1999]) in the Banks Islands (V. Bretagnolle and H. Shirihai  in litt. 2016) and, historically in Vanuatu, Samoa and Fiji. In the Line Islands, c.1,000 pairs were present on Kiritimati (= Christmas Island) in the 1960s and early 1970s (Garnett 1983) but, in 1993, the population was estimated at several hundred (M. Rauzon in litt. 1999), supported by observations in 1999 and 2007-15 (D. Watling in litt. 1999, R. Pierce in litt. 2015). In the Phoenix Islands, c.1,400 birds were present on Phoenix and McKean Islands, but the total population on the two islands is now thought to be 100+ pairs  and c.10 individuals respectively (Garnett 1983, R. Pierce 2013). In the Australs, tens of pairs occurred on Rapa and surrounding islets (Holyoak and Thibault 1984), and the situation was unchanged in 1990 (Thibault and Varney 1991). However, following Cyclone Oli in February 2010, 36 dead birds were found in the port of Tubuai, (possibly through the combined effects of light-attraction and strong winds), which may have had a significant impact on the small local population around Rapa and the long-term survival of the species in French Polynesia (Anon. 2009). In the Gambiers, 100-200 pairs occurred on Motu Teiku and 100-300 pairs on Manui in 1996, but it may have become extinct on two further islands (Thibault and Bretagnolle 1999). In the Marquesas, one pair was found on Ua Pou in 1989 (V. Bretagnolle in litt. 1999). No evidence was found of this species during a survey of the historical nesting site of Mt Washington (=Nabukulevu) on Kadavu (Fiji) in August 2004. There has been only one unconfirmed sighting in Fijian waters in the last three decades, and it is thought to be very unlikely that it still breeds in Fiji (D. Watling in litt. 2005).

Ecology

It usually nests in loosely formed colonies throughout the year, peaking at different times on different islands (Holyoak and Thibault 1984, Carboneras 1992c). Burrows are often dug in sand (and can be extremely fragile) (V. Bretagnolle in litt. 1999), but more often nests under vegetation or in rock-crevices (Holyoak and Thibault 1984, R. Pierce in litt. 2006, 2007). It feeds on small fish, cephalopods and crustaceans (Holyoak and Thibault 1984, Carboneras 1992c).

Threats

Birds do not appear to survive in the presence of rats or cats except on some Rattus exulans infested islets and where storm-petrels are recruited from neighbouring islets (Garnett 1983, Holyoak and Thibault 1984, Jones et al. 2008, Pierce in litt. 2006, 2007). Predation of eggs and small chicks by house mouse Mus musculus (E. Flint in litt. 2000), loss of vegetation cover by rabbits (Pierce in litt. 2006, Pierce 2013), human exploitation (Carboneras 1992c) and increasing cultivation of islets, e.g. on Rapa (V. Bretagnolle in litt. 1999), are additional threats. 

Conservation actions

Conservation Actions Underway

On Kiritimati, a cat eradication programme failed to limit predation by feral cats outside villages (M. Rauzon in litt. 1999, E. A. Schreiber in litt. 1999) but, at Jarvis Island National Wildlife Refuge (200 miles from Kiritimati), a colonisation programme has been successful and, in March 2000, three N. fuliginosa were observed displaying (Flint and Aycock 2000). A total of 23 motu in the central lagoon area has been successfully targeted for rat eradication, with more eradications on additional motu planned for the future (R. Pierce and D. Brown in litt. 2009, 2011). In New Caledonia, the Société Calédonienne d'Ornithologie was due to implement a rat eradication program on 18 islets including the site of the only previously known colony in 2007-2008 to restore suitable breeding conditions for the species (V. Chartendrault in litt. 2007). Successful rabbit and rat eradication occurred on McKean and Phoenix Island in 2008 and on Birnie in 2011,  (R. Pierce et al. in litt. 2008, R. Pierce in litt. 2009, Pierce 2013). Rats were targeted at Temoe in 2015 and rabbits on Manui in 2015 (SOP Manu, BirdLife).  

Conservation Actions Proposed

Survey all nesting islets (M. Rauzon in litt. 1999) including those off the main Samoan islands (SPREP 1999). Check status on islands and islets from which rats and cats have been targeted within its breeding range, e.g. Temoe Island (SOP Manu, BrdLife, and throughout the Line and Phoenix Islands (Pierce 2013, Pierce 2015 in litt.). Check other islands that could be rat-free including in Solomons (R. Pierce in litt. 2016)


Identification

25 cm. Large, polymorphic storm-petrel with broad rounded wings, lacking obvious bends along leading and trailing edges. Most common morph has brownish-black head, nape, mantle, upperwing and tail but white rump-band and greater-covert wing-bar. Moderately forked tail. White throat, brownish chest band, rest of underparts white. Extensive white on underwing-coverts, otherwise dark underwing. Intermediate morphs show dark flecking on white underparts. Dark morph is entirely sooty-brown. Similar spp. Dark morph similar to but larger than Tristram's Storm Petrel O. tristrami.

Acknowledgements

Text account compilers
Anderson, O., Calvert, R., Mahood, S., McClellan, R., Moreno, R., O'Brien, A., Stattersfield, A., Temple, H.

Contributors
Flint, B., Chartendrault, V., Pierce, R., Watling, D., Rauzon, M., Kepler, A., Pandolfi, M., Wragg, G., Baudat-Franceschi, J., Bretagnolle, V., Schreiber, E.


Recommended citation
BirdLife International (2017) Species factsheet: Nesofregetta fuliginosa. Downloaded from http://www.birdlife.org on 21/09/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/09/2017.