Species

Justification
This species had been predicted to undergo a moderately rapid population decline in the near future but has instead shown a significant increase during the past two decades (probably owing to greater availability of carrion from expanding populations of fur seals, increased waste from commercial fishing operations, and the use of measures to reduce seabird bycatch around some breeding colonies). It no longer approaches the threshold for classification as Threatened and has therefore been downlisted from Near Threatened to Least Concern.

Taxonomic source(s)
Brooke, M. De L. 2004. Albatrosses and petrels across the world. Oxford University Press, Oxford.
Christidis, L.; Boles, W. E. 1994. The taxonomy and species of birds of Australia and its territories. Royal Australasian Ornithologists' Union, Melbourne.
Christidis, L.; Boles, W. E. 2008. Systematics and taxonomy of Australian birds. CSIRO Publishing, Collingwood, Australia.
Dowsett, R. J.; Forbes-Watson, A. D. 1993. Checklist of birds of the Afrotropical and Malagasy regions. Tauraco Press, Li
SACC. 2006. A classification of the bird species of South America. Available at: http://www.museum.lsu.edu/~Remsen/SACCBaseline.html.
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.
Stotz, D. F.; Fitzpatrick, J. W.; Parker, T. A.; Moskovits, D. K. 1996. Neotropical birds: ecology and conservation. University of Chicago Press, Chicago.
Turbott, E. G. 1990. Checklist of the birds of New Zealand. Ornithological Society of New Zealand, Wellington.

Identification
90 cm. Giant petrel with huge bill. Adult: grey-brown body with paler forehead, sides of face and chin; bill 90-105 mm, pinkish-yellow horn tipped pink-brownish; eye grey to off-white; juvenile: completely dark brown fading with age. Similar spp. M. giganteus has whiter head, and is occasionally completely white; eye generally brown; pale leading edge to wing; tip of bill green.

Distribution and population
Macronectes halli breeds at South Georgia (Georgias del Sur), Prince Edward Islands (South Africa), Crozet and Kerguelen Islands (French Southern Territories), Macquarie Island (Australia), Auckland, Campbell, Antipodes and Chatham Islands and, historically, on islets off Stewart Island (New Zealand). The world population in the 1980s was estimated at c.8,600 pairs (Hunter 1985). A more recent estimate (late 1990s) is 11,500 pairs, an apparent increase of 34% (Patterson et al. undated), which may be partly attributable to better monitoring, but also probably reflects greater availability of carrion from expanding populations of fur seals Arctocephalus gazella and A. tropicalis, increased waste from commercial fishing operations (Patterson et al. undated), and use of measures to reduce seabird bycatch around some breeding colonies, such as South Georgia (Georgias del Sur).




Population justification
The largest population is on South Georgia (Georgias del Sur), with c.4,500 pairs. followed by Chatham Islands (c.2000 pairs on the Forty-Fours and 80-100 pairs on Middle Sister), Iles Kerguelen (1,450-1,800 pairs), Iles Crozet (1,300 pairs), Macquarie Island (c.1,300 pairs), Prince Edward Island (650 pairs), Antipodes Island (230 pairs), Campbell Island (230 pairs) and the Auckland Group (50 pairs). In total, the population is estimated to number 11,000-14,000 individuals, roughly equivalent to 17,000-21,000 individuals in total.

Trend justification
Recent data indicate population increases may be occurring. In the 1980s, the world population was estimated to number c.8,600 pairs (Hunter 1985). A more recent estimate, from the late 1990s is 11,500 pairs, an apparent increase of 34 % (Patterson et al. undated). A comprehensive survey of all known breeding sites in the South Georgia archipelago between 2005 and 2006 suggests that there has been a c.30 % increase in the last two decades (Poncet et al. in litt. 2008). The Marion Island and possibly the Prince Edward Island populations are also increasing and numbers are stable or increasing at Macquarie (Woehler and Croxall 1999). The Possession Island (Crozet) population, which decreased between the 1980s and 1992, may now be increasing (Bretagnolle et al. 1991, H. Weimerskirch unpublished data). These increases probably reflect greater availability of carrion from expanding populations of fur seals Arctocephalus gazella and A. tropicalis, increased waste from commercial fishing operations (Patterson et al. undated), and use of measures to reduce seabird bycatch around some breeding colonies, such as South Georgia (Georgias del Sur). A recent census on the Antipodes Islands counted 230 breeding pairs, but since this was the first full count, the trend is not known (Wiltshire and Hamilton 2003).


Ecology
Where they co-exist at the same location, Northern Giant-petrels breed approximately six weeks before Southern Giant-petrels (Hunter 1987, De Bruyn et al. 2007). Birds feed on penguin and pinniped carrion, cephalopods, krill, offal, discarded fish and refuse from ships, often feeding near trawlers and longliners (Hunter and Brooke 1982, Hunter 1983). Males and females exhibit clearly defined spatial segregation in foraging ranges (Hunter 1983, Gonzalez Solis et al. 2000, Becker et al.2002, Gonzalez-Solis and Croxall 2005). During the breeding season, males exploit scavenging opportunities in and around seal and penguin colonies and are coastal in distribution, whereas females are much more dependent on pelagic resources (Patterson and Fraser 2003, BirdLife International 2004, Quintana and Dell'Arciprete). There is significant sexual dimorphism, with female mass approximately 80% that of males (Gonzalez-Solis 2004). Ringing recoveries indicate juveniles forage more widely than adults (Hunter 1984a). At some sites, its less colonial breeding habit may make it less sensitive to human disturbance than Southern Giant-petrel, though degree of coloniality does not differ on South Georgia (Georgias del Sur), the largest breeding colony (R. A. Phillips in litt. 2008). On the Chatham Islands, regurgitations from the birds on the Forty-Fours indicate a reliance on natural food sources (esp.Gnathophausia ingens) rather than carrion - there being no penguin colonies in the Chatham Islands (C. J. R. Robertson in litt. 2008). Average age of first breeding is c.10 years, and mean adult annual survival at South Georgia is 90% (Hunter 1984a).

Threats
A total of 2,000-4,000 giant-petrels were estimated killed in illegal or unregulated Southern Ocean longline fisheries for Patagonian toothfishDissostichus eleginoides in 1997-1998 (CCAMLR 1997, CCAMLR 1998). Improved mitigation in a number of Patagonian Toothfish longline fisheries around breeding colonies (including South Georgia {Georgias del Sur}) has led to a reduction in observed bycatch of this species in these areas. Secondary mortality (ingested hooks) and mortality associated with IUU fishing may still be a threat. On the Chatham Islands, fisheries bycatch returned by observers from NZ waters 1996-2005 returned only 17 birds (8 from trawl fisheries and 9 from longline) (C. J. R. Robertson in litt. 2008).

Conservation actions underway
CMS Appendix II and ACAP Annex 1.

Conservation actions proposed
Conduct surveys of major breeding sites. Continue monitoring. Minimise disturbance at breeding sites. Research movements and migration. Promote adoption of best-practice mitigation measures in all fisheries within its range, including via intergovernmental mechanisms such as ACAP, FAO and Regional Fisheries Management Organisations.

References
Jouventin, P.; Martinez, J.; Roux, J. -P. 1989. Breeding biology and current status of the Amsterdam Island Albatross. Ibis 131: 171-189.

Hunter, S. 1983. The food and feeding ecology of the giant petrels Macronectes halli and M. giganteus at South Georgia. Journal of Zoology (London) 200: 521-538.

Hunter, S. 1984. Movements of South Georgia giant petrels Macronectes spp. ringed at South Georgia. Ringing & Migration 5(2): 105-112.

Hunter, S. 1985. The role of giant petrels in the Southern Ocean ecosystem. In: Siegfried, W.R.; Condy, P.R.; Laws, P.R. (ed.), Antarctic nutrient cycles and food webs, pp. 534-542. Springer-Verlag, Berlin.

Weimerskirch, H.; Zotier, R.; Jouventin, P. 1989. The avifauna of the Kerguelen Islands. Emu 89: 15-29.

Bretagnolle, V.; Weimerskirch, H.; Jouventin, P. 1991. Have giant petrels Macronectes spp. really increased at îles Crozet? Marine Ornithology 19: 73-74.

CCAMLR. 1998. Report of the XVII meeting of the Scientific Committee.

CCAMLR. 1997. Report of the XVI meeting of the Scientific Committee.

BirdLife International. 2004. Tracking ocean wanderers: the global distribution of albatrosses and petrels. BirdLife International, Cambridge, U.K.

Woehler, E. J.; Croxall, J. P. 1999. The status and trends of Antarctic and subantarctic seabirds. Marine Ornithology 25: 43-66.

Taylor, G. A. 2000. Action plan for seabird conservation in New Zealand. Department of Conservation, Wellington.

González-Solís, J.; Croxall, J. P.; Wood, A. G. 2000. Foraging partitioning between giant petrels Macronectes spp. and its relationship with breeding population changes at Bird Island, South Georgia. Marine Ecology Progress Series 204: 279-288.

Wiltshire, A. J.; Scofield, R. P. 2000. Population estimate of breeding Northern Giant Petrels Macronectes halli on Campbell Island, New Zealand. Emu 100: 186-191.

Wiltshire, A.; Hamilton, S. 2003. Population estimate for northern giant petrel (Macronectes halli) on Antipodes Island, New Zealand. Notornis 50: 128-132.

Brooke, M. De L. 2004. Albatrosses and petrels across the world. Oxford University Press, Oxford.

Patterson, D. L.; Woehler, E.J.; Croxall, J. P.; Cooper, J.; Poncet, S.; Fraser, W. R. 2008. Breeding distribution and population status of the Northern Giant Petrel Macronectes halli and Southern Giant Petrel M. giganteus. Marine Ornithology 36: 115-124.

Hunter, S.; Brooke, M. de. L. 1992. The diet of giant petrels Macronectes spp. at Marion Island, southern Indian Ocean. Colonial Waterbirds 15: 56-65.

Gonzalez-Solis, J.; Croxall, J. P. 2005. Differences in foraging behaviour and feeding ecology in giant petrels. In: Ruckstuhl, K.E.; Neuhaus, P. (ed.), Sexual segregation in vertebrates: ecology of the two sexes, pp. 92-111. Cambridge University Press, Cambridge, U.K.

Gonzalez-Solis, J. 2004. Sexual size dimorphism in Northern Giant Petrels: ecological correlates and scaling. Oikos 105: 247-254.

De Bruyn, N. P. J.; Cooper, J.; Bester, M. N.; Tosh, C. A. 2007. The importance of land-based prey for sympatrically breeding Giant Petrels at sub-Antarctic Marion Island. Antarctic Science 19: 25-30.

Hunter S. 1987. Species and sexual isolation mechanisms in sibling species of Giant Petrels Macronectes. Polar Biology 7: 295-301.

Becker, P. H.; Gonzalez-Solis, J.; Behrends, B.; Croxall, J. P. 2002. Feather mercury levels in seabirds at South Georgia: Influence of trophic position, sex and age. Marine Ecology Progress Series 243: 261-269.

Patterson, D. L.; Fraser, W. R. 2003. Satellite tracking Southern Giant Petrels at Palmer Station, Antarctica. Microwave Telemetry, Inc. Newsletter 8: 3-4.

Quintana F., Dell'Arciprete, O. P. 2002. Foraging grounds of southern giant petrels (Macronectes giganteus) on the Patagonian shelf . Polar Biology 25(2): 159-161.

Further web sources of information
Additional information is available on the distribution of the Northern Giant-petrel from the Global Procellariiform Tracking Database (http://www.seabirdtracking.org)

Australian Govt - Action Plan for Australian Birds 2000 - Recovery Outline

Hear sounds for this species from xeno-canto, the community database of shared bird sounds from around the world.

View photos and videos, and hear sounds of this species from the Internet Bird Collection

Text account compilers
Bird, J., Black, A., Sullivan, B., Symes, A.

Contributors
Baker, B., Croxall, J., Patterson-Fraser, D., Phillips, R., Robertson, C., Weimerskirsch, H.

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2013) Species factsheet: Macronectes halli. Downloaded from http://www.birdlife.org on 21/05/2013. Recommended citation for factsheets for more than one species: BirdLife International (2013) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/05/2013.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Additional resources for this species

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