Sooty Shearwater Ardenna grisea Scientific name definitions

The Sooty Shearwater is one of the most common seabirds in the world and easily the most common member of its genus. They breed in enormous colonies in both the south Pacific and Atlantic Oceans on islands off southeast Australia, New Zealand and Tierra del Fuego (South America) where certain breeding congregations can exceed 2.5 million pairs. When not breeding the Sooty Shearwater embarks upon one of largest mass migrations known. Shortly after fledging the population begins to move towards the northwest corner of their respective oceans and following the prevailing winds, eventually move to the east arriving in western North America and Europe late in the local summer. From there they move south back to their breeding grounds. The species is also the only shearwater that can be legally harvested in New Zealand, with the native Maoris taking up to 250,000 chicks for food, soap and oil.

40–51 cm; 650–978 g; wingspan 94–109 cm. Largish dark shearwater  with relatively narrow, pointed wings, and pale areas on central underwing  . Most of plumage rather uniform sooty-brown to dark greyish , usually darkest on head  and on upper surface of primaries  and tail, dorsal area may have scaly pattern, especially on scapulars; chin and upper throat slightly paler, rest of underparts from upper chest similar to upperparts  but slightly paler; axillaries dark, underwing-coverts  paler brownish or grey, with variable amount of white on innermost greater coverts, median and lesser coverts, often whitest on lesser and especially median primary-coverts, many usually with narrow dark shaft-streaks, remiges dark greyish, slightly and diffusely paler at primary bases; iris blackish brown; bill brownish grey to dark grey, sometimes blacker at tip; legs and feet pale flesh, dull pink-flesh or greyish, the outer side of tarsus and outer toe often tinged dusky. Sexes alike. Juvenile as adult, but is in fresh plumage May–Jul when most older birds are in wing moult (1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ). Most similar to A. tenuirostris but usually has less rounded head with longer bill , usually only slight or no contrast between cap and throat, underwing has large whitish area on carpal contrasting with dark greater primary-coverts and bases of primaries, while in profile at very close range the bill tends to form three broadly equal parts (maxillary unguis, culminicorn and nostril tube), whereas in A. grisea the culminicorn appears longer than the other two parts, although it is unclear how useful this feature might be. From Puffinus mauretanicus and other similar smallish shearwaters by larger size, heavier body, long narrow pointed wings, and plainer dark abdominal area; whitish on underwing prevents confusion with other dark shearwaters, bill colour and proportions additionally assist versus A. carneipes, while long slender bill with no white at its base useful versus some dark Pterodroma.

All major oceans except N Indian Ocean, breeding in S Chile and Falkland Is, in Tristan da Cunha (2 Ryan, P.G., Dean, W.R.J., Moloney, C.L., Watkins, B.P. and Milton, S.J. (1990). New Information on seabirds at Inaccessible Island and other islands in the Tristan da Cunha Group. Marine Orn. 18(1–2): 43–54. Close ), and in SE Australia and New Zealand area.

Marine ; generally occurs in cold offshore and pelagic waters; satellite-tracking studies in US waters (i.e. during the non-breeding period) over two different years found that the species spent 68% and 46% of time over continental shelf (< 200 m) waters, 27% and 43% of time over the slope (200–1000 m), and 5% and 11% of time over continental rise and abyssal regions (>1000 m), respectively (3 Adams, J., MacLeod, C., Suryan, R.M., Hyrenbach, K.D. and Harvey, J.T. (2012). Summer-time use of west coast US National Marine Sanctuaries by migrating sooty shearwaters (Puffinus griseus). Biological Conservation. 156: 105–116. Close ). Breeds on slopes, often covered with dense vegetation  , usually Poa tussock but also Olearia forest (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ), mainly near sea but also inland, up to 1500 m above sea-level, typically on islands but also mainland headlands (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ).

Transequatorial migrant, moving into N Pacific (where more abundant) and N Atlantic ; non-breeders depart first, followed by breeders in mid Apr and fledglings on average c. 1 month later (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ). Migratory pathways are generally poorly known, although in Pacific there are records from Papua New Guinea (5 Bailey, S.F. (1992). Seabirds of Madang Province, Papua New Guinea, September–November 1989. Emu 92(4):223–232. Close ), New Caledonia (6 Shirihai, H. (2007). A Complete Guide to Antarctic Wildlife. The Birds and Mammals of the Antarctic Continent and the Southern Ocean. Second edition. A. & C. Black, London, UK. Close ), Tonga, Samoa, Fiji, Kiribati, Cook Is, Society Is and Marquesas (7 Grant, G.S., Trail, P.W. and Clapp, R.B. (1994). First specimens of Sooty Shearwater, Newell’s Shearwater, and White-faced Storm-Petrel from American Samoa. Notornis. 41(3): 215–217. Close , 8 VanderWerf, E.A., Pierce, R.J., Gill, V.A., Wragg, G., Raust, P. and Tibbitts, T.L. (2006). Pelagic seabird surveys in the Tuamotu and Gambier archipelagos, French Polynesia. Marine Ornithology 34(1):65–70. Close ). Large numbers first head into NW sector of respective ocean, arriving late Apr/early Jun, then progressively move E following prevailing winds to reach W coasts of North America and Europe late in local summer, with return migration commencing in late Aug and completed by early Dec (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ); many thus complete wide loop before returning to breeding islands; however, non-breeders were suspected (9 Spear, L.B. and Ainley, D.G. (1999). Migration routes of Sooty Shearwaters in the Pacific Ocean. Condor. 101(2): 205–218. Close ) (and have been recently confirmed through satellite-tagging) (10 Shaffer, S. A., Y. Tremblay, H. Weimerskirch, D. Scott, D. R. Thompson, P. M. Sagar, H. Moller, G. A. Taylor, D. G. Foley, B. A. Block, and D. P. Costa (2006). Migratory shearwaters integrate oceanic resources across the Pacific Ocean in an endless summer. Proceedings of the National Academy of Sciences of the United States of America 103:12799–12802. Close ) to perform figure-of-eight loop totalling 64,000 km over the Pacific, E to the Peru Current (Jan–Apr?), NW to N Pacific (Mar–May), then E to California Current (May–Oct, though present from Mar and peak numbers only until Aug, with juveniles arriving from Jun), and finally SW through C Pacific back to New Zealand (Aug–Dec) (1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ), covering up to 910 km/day (10 Shaffer, S. A., Y. Tremblay, H. Weimerskirch, D. Scott, D. R. Thompson, P. M. Sagar, H. Moller, G. A. Taylor, D. G. Foley, B. A. Block, and D. P. Costa (2006). Migratory shearwaters integrate oceanic resources across the Pacific Ocean in an endless summer. Proceedings of the National Academy of Sciences of the United States of America 103:12799–12802. Close ), whereas breeders cover c. 29,000 km (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ). In Pacific, particularly large concentrations have been observed E of Japan, off Kurils (May–Oct) and Gulf of Alaska region (1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ), as well as within 100 km of California, in Monterey Bay (> 5,000,000 birds, at least formerly; see Status and Conservation), but also in Hecate Strait, British Columbia (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close , 1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ). Occasionally recorded inland in SW USA (especially at Salton Sea) and off W North America small numbers remain beyond Nov, even throughout boreal winter, sometimes as far N as British Columbia; generally uncommon to rare further S, off Middle America, at any season, mainly Mar/Apr and Sept/Oct (1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ). Most South American birds may move fairly directly up and down W coasts of Americas, perhaps especially during years of poor productivity in Humboldt Current (1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ), although large numbers have been observed only as far N as C Chile in Jun (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ) and at least some obviously move N in Atlantic, reaching E North America (N as far as SE Baffin I and SW Greenland) by Apr (mainly present Jun–Sept), thereafter mainly moving E across N Atlantic in Jul–Sept (where concentrations noted over Rockall Bank and around Faeroes, and recorded as far N as Bear I) (11 Snow, D. W., and C. M. Perrins, Editors (1998). The Birds of the Western Palearctic. Concise Edition. Volume 1. Non-passerines. Oxford University Press, Oxford, UK. Close ), before moving S again (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ), with signficant passage recently recorded off Gabon in Oct (12 Passavy, G. (2011). Migration of the Sooty Shearwater Puffinus griseus off Gabon. Marine Orn.. 39(2): 147–150. Close ) (occasionally entering Baltic with records as far as Poland, Finland and Latvia, penetrates Mediterranean as far as Israel, and recorded well inland, for example in Switzerland) (11 Snow, D. W., and C. M. Perrins, Editors (1998). The Birds of the Western Palearctic. Concise Edition. Volume 1. Non-passerines. Oxford University Press, Oxford, UK. Close , 13 Bonaccorsi, G. (2003). Les Procellariiformes (Diomedeidae, Procellariidae et Hydrobatidae) non nicheurs en Méditerranée occidentale: une synthèse [Non-breeding procellariiformes (Diomedeidae, Procellariidae and Hydrobatidae) in the west of the Mediterranean]. Alauda 71(1):1–7. Close , 14 Schweizer, M. (2005). Seltene Vogelarten und ungewöhnliche Vogelbeobachtungen in der Schweiz im Jahre 2004. Ornithologische Beobachter 102:251–270. Close ), although some appear not to cross Atlantic, instead remaining off NE North America until about Nov, much more rarely Dec (exceptionally Jan–Apr), and only very occasionally enters Caribbean or Gulf of Mexico (15 Jones, H.L. (2002). Erroneous and unconfirmed bird records frorn Belize: setting the record straight. Bull. Brit. Orn. Club. 122(3): 201–216. Close , 16 Alvarez-León, R., Labercome, B. and Moreno-Bejarano, L.M. (2003). First record of nine birds species from Río Magdalena, Colombian Caribbean. Rev. Biol. Tropical. 51(1): 261–284. Close ) (although records there are year-round), with exceptional inland records in USA (as far as Alabama) (1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ). Records in the W Mediterranean have sharply increased during the last decades, being mostly in spring (40% in Mar–May) (17 Olioso, G. (2015). Statut historique et récent du Puffin fuligineux Puffinus griseus en Méditerranée occidentale [Status of Sooty Shearwater in the western Mediterranean.] Ornithos. 22(5): 264–269. In French with English summary. Close ). In E Atlantic recorded as late as Jan in Gulf of Guinea (18 Pérez del Val, J., Castroviejo, J. and Purroy, F.J. (1997). Species rejected from and added to the avifauna of Bioko Island (Equitorial Guinea). Malimbus. 19(1): 19–31. Close ). Some birds remain in Southern Ocean over winter, for example off New Zealand (19 Petyt, C. (1995). Behaviour of seabirds around fishing trawlers in New Zealand subantarctic waters. Notornis. 42(2): 99–115. Close ) and in South African waters, especially off S & W coasts, where the species is also present at other seasons (presumably non- or failed breeders), but perhaps also pre-breeders from New Zealand colonies (20 Cooper, J., Underhill, L.G. and Avery, G. (1991). Primary molt and transequatorial migration of the Sooty Shearwater. Condor. 93(4): 724–730. Close ). Generally reported not to move N in Indian Ocean, but recorded in Gulf of Eilat in spring and summer (though overland passage between Mediterranean and Red Sea is known) (21 Shirihai, H. (1996). The Birds of Israel: A Complete Avifauna and Bird Atlas of Israel. Academic Press, London, UK. Close , 22 Andrews, I.J., Khoury, F. and Shirihai, H. (1999). Jordan Bird Report 1995–97. Sandgrouse 21(1):10–35. Close ) and is vagrant off Oman (eight records, Apr–Oct) (23 Eriksen, J., and R. Victor (2013). Oman Bird List: the Official List of the Birds of the Sultanate of Oman. Seventh edition. Sultan Qaboos University, Muscat, Oman. Close ), Iran (Jun 2008) (24 Ghasemi, M., Goudarzi, F. and Ram, M. (2008). The first report of Sooty Shearwater Puffinus griseus in Iran. Podoces. 3(1–2): 101–102. Close ), United Arab Emirates (eight records, all since 1995) (25 Moran, N. (2006). Bird sites of the OSME region - 1 and 2. Sandgrouse. 28(2): 176–179. Close ) and to Kenya (May 2004) (26 Jackson, C. and Valle, S. (2007). Sooty Shearwater Puffinus griseus: a new species for eastern Africa. Scopus. 26(1): 31–33. Close ), with two undocumented records from Sri Lanka often regarded as referring to another species (27 Praveen, J., R. Jayapal, and A. Pittie (2013). Notes on Indian rarities–1: Seabirds. Indian Birds 8(5):113–125. Close ). During breeding season, New Zealand breeders feed over S Pacific and Tasman Sea, but also travel S to Antarctic pack ice (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ). Recent satellite tracking efforts during this period has revealed the extraordinary dispersal abilities of this species: during pre-laying exodus, one male flew a minimum of 7700 km over 34 days, another flew 4200 km during 28 days and the minimum distance covered by a female was 3700 km during 16 days; pre-breeders mainly frequented waters < 1000 m deep, and during the mid-breeding period a male flew a minimum of 18,000 km in 36 days, while the female flew 4100 km in 13 days (28 Söhle, I.S., Robertson, C.J.R., Nicholls, D.G., Mouritsen, H., Frost, B. and Moller, H. (2007). Satellite tracking of sooty shearwaters (Puffinus griseus) during their pre-laying “exodus” and incubation. Notornis. 54(3): 180–188. Close ).

Mainly small shoaling fish, cephalopods (Onychoteuthis, Gonatus, Loligo opalescens) and crustaceans, proportions varying with season and locality, although most available data are from non-breeding season (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ); fish include anchovies (Engraulis), spawning capelin (Mallotus villosus), young of Helecolenus/Neosebastes and Cololabis saire. During breeding season, diet apparently dominated by euphausiid crustacea, especially Nyctiphanes australis, and myctophid fish, with the former caught during short foraging trips and the latter on longer trips during chick-rearing period (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ), while other foods at this period include arrow squid (Nototodarus sp.) and amphipods (Hyperiella antarctica) (29 Cruz, J., Kitson, J. and Lyver, P. (1998). Seafood smorgasbord for Sooty Shearwaters Puffinus griseus. Ostrich. P. 370 in:. Close ). Feeds mainly by pursuit-plunging and diving from heights of 3–5 m and regularly reaching 30–40 m below surface (exceptionally 67 m) (30 Weimerskirch, H. and Sagar, P.M. (1996). Diving depths of Sooty Shearwaters Puffinus griseus. Ibis. 138(4): 786–788. Close ), sometimes also by surface-seizing and hydroplaning. Frequently associates in large numbers with other seabirds, especially other Procellariiformes, penguins, gulls, cormorants (e.g. Imperial Shag Phalacrocorax atriceps) (31 Cooper, J. (2008). King Cormorants Phalacrocorax [atriceps] albiventer foraging from within a Sooty Shearwater Puffinus griseus raft. Marine Orn.. 36(2): 192. Close ), pelicans (1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ) and terns, as well as sometimes with cetaceans (6 Shirihai, H. (2007). A Complete Guide to Antarctic Wildlife. The Birds and Mammals of the Antarctic Continent and the Southern Ocean. Second edition. A. & C. Black, London, UK. Close ). Birds sometimes attend trawlers in large numbers (> 2000 birds) (19 Petyt, C. (1995). Behaviour of seabirds around fishing trawlers in New Zealand subantarctic waters. Notornis. 42(2): 99–115. Close ), probably mostly juveniles.

Noisy at colonies, but probably mostly silent at sea (6 Shirihai, H. (2007). A Complete Guide to Antarctic Wildlife. The Birds and Mammals of the Antarctic Continent and the Southern Ocean. Second edition. A. & C. Black, London, UK. Close ). Mostly vocalizes on ground or from burrow, but only comparatively rarely in flight, with the main call, a repeated eerie cat-like howling “wheeoohar”, hoarse moaning “der-rer-ah” or a higher-pitched “coo-roo-ah”, made partly through inhalation and partially by exhalation; male calls are perhaps higher-pitched, while in courtship pairs duet (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ).

Starts late Sept/early Oct with return to colony, followed by pre-laying exodus of c. 14 days, egg-laying from mid Nov to early Dec in New Zealand (with little inter-annual variation, and two-thirds of eggs laid 20–24 Nov on Snares), hatching from mid Jan and fledging in late Apr/early May (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ). Monogamous, although pair-bonds are suspected to survive just one season; defends burrow entrance (6 Shirihai, H. (2007). A Complete Guide to Antarctic Wildlife. The Birds and Mammals of the Antarctic Continent and the Southern Ocean. Second edition. A. & C. Black, London, UK. Close ). Highly colonial  , at densities of up to 1·9 burrows/m² in Poa tussock and 1·2/m² in Olearia forest (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ), but more typically 0·3–0·9 burrows/m² (32 Charleton, K., Bragg, C., Knight, B., Fletcher, D., Moller, H., Newman, J. and Scott, D. (2009). Spatial variation in burrow entrance density of the sooty shearwater (Puffinus griseus). Notornis. 56(1): 1–10. Close ), sharing breeding grounds with White-faced Storm-petrels (Pelagodroma marina), Pachyptila vittata, Common Diving-petrels (Pelecanoides urinatrix), Grey-backed Storm-petrels (Garrodia nereis) and Pterodroma axillaris on South East I (Chathams) (33 West, J.A. and Nilsson, R.J. (1994). Habitat use and burrow densities of burrow-nesting seabirds on South East Island, Chatham Islands, New Zealand. Notornis. 41(Suppl.): 27–37. Close ); nests in self-excavated burrows  up to 3 m long (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ), with sparse lining, sometimes in cavities, and can be out-competed for nest-sites by Snares Penguins (Eudyptes robustus) on archipelago of same name (6 Shirihai, H. (2007). A Complete Guide to Antarctic Wildlife. The Birds and Mammals of the Antarctic Continent and the Southern Ocean. Second edition. A. & C. Black, London, UK. Close ). Single white egg  , mean size 77·4 mm × 48·3 mm, mass 95 g (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ); incubation 53–56 days, with stints of 4–9 days; chicks  have smoky grey down  with paler underparts, brooded for 2–5 days and then fed on average every 0·35 days, the adults alternating between short (1–3 day) and long (5–15 day) trips, delivering mean meals of 96 g and 193 g, respectively (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ); fledging 86–106 (mean 97) days at mean weight of 746 g, while it has been suggested that peak mass is achieved around 70 days (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ). Mass at fledging appears to influence future survival prospects: of fledglings with a mass in range 564–900 g, 5·4% were recaptured compared to 13 of fledglings in the range 901–1415 g (34 Sagar, P.M. and Horning, D.S. (1998). Mass-related survival of fledgling Sooty Shearwaters Puffinus griseus at The Snares, New Zealand. Ibis. 140(2): 329–331. Close ). Sexual maturity probably at 5–9 years, although first return to colonies is any time between age two and ten years (mean 4·8 years), while mean age of first breeding has been calculated at 7·7 years (35 Fletcher, D., Moller, H., Clucas, R., Bragg, C., Scott, D., Scofield, P., Hunter, C.M., Win, I., Newman, J., McKechnie, S., Cruz, J. and Lyver, P. (2013). Age at first return to the breeding colony and juvenile survival of Sooty Shearwaters. Condor. 115(3): 465–476. Close ). Estimates of annual survival prior to two years old 0·54 at Taiaroa Head, South I, and 0·41 at the Snares during same study (35 Fletcher, D., Moller, H., Clucas, R., Bragg, C., Scott, D., Scofield, P., Hunter, C.M., Win, I., Newman, J., McKechnie, S., Cruz, J. and Lyver, P. (2013). Age at first return to the breeding colony and juvenile survival of Sooty Shearwaters. Condor. 115(3): 465–476. Close ). Adult survival c. 93% (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ).

Not globally threatened. Currently considered Near Threatened. Abundant and widespread, with total population of several million birds, including perhaps 4,000,000 pairs in New Zealand alone and 20,000,000 birds in total, although there is evidence for a decline over past c. 3 decades (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ). Probably 2,750,000 breeding pairs on Snares Is (1970/71), but 2,060,000 pairs in 1996–2000, a decline of c. 37%, while other colonies in New Zealand region are also decreasing (as partially indicated by beached bird surveys) (36 Scofield, R.P. and Christie, D. (2002). Beach patrol records indicate a substantial decline in sooty shearwater (Puffinus griseus) numbers. Notornis. 49(3): 158–165. Close ) or have not responded to predator control (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ); has been suggested that at least some mainland colonies are no longer extant (37 Hamilton, S.A., Moller, H. and Robsertson, C.J.R. (1997). Distribution of Sooty Shearwater (Puffinus griseus) breeding colonies along the Otago Coast, New Zealand, with indication of countrywide population trends. Notornis. 44(1): 15–25. Close ). Elsewhere, colonies on 17 Australian islands all small (< 1000 pairs) and totalling just 1300–3500 pairs (38 Baker, G. B., R. Gales, S. Hamilton, and V. Wilkinson (2002). Albatrosses and petrels in Australia: a review of their conservation and management. Emu 102(1):71–97. Close ), with c. 10,000–20,000 pairs in the Falklands (39 Woods, R. W., and A. Woods (1997) Atlas of Breeding Birds of the Falkland Islands. Anthony Nelson, Oswestry, UK. Close ), but many more in S Chile, where some colonies are estimated to number up to 200,000 pairs (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ) and recently confirmed to breed on Tristan da Cunha, with breeding also suspected on Inaccessible I (6 Shirihai, H. (2007). A Complete Guide to Antarctic Wildlife. The Birds and Mammals of the Antarctic Continent and the Southern Ocean. Second edition. A. & C. Black, London, UK. Close ). Numbers present in California Current during non-breeding season have declined by 90% over the past 20 years (40 Veit, R. R., J. A. McGowan, D. G. Ainley, T. R. Wahl, and P. Pyle (1997). Apex marine predator declines ninety percent in association with changing oceanic climate. Global Change Biology 3:23–28. Close ), with for example daily counts in 1970s of up to 10,000 declining to just c. 10 birds in 1990s, although it has been suggested that numbers have shifted to W & C Pacific tracking cooler waters (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close , 1 Howell, S. N. G. (2012). Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey, USA. Close ). Only petrel species that can legally be sold in New Zealand area; important commercial exploitation, with up to 250,000 young taken yearly by local Maoris (who typically select larger and better-developed chicks) (41 Hunter, C.M., Moller, H. and Kitson, J. (2000). Muttonbirder selectivity of Sooty Shearwater or Titi Puffinus griseus chicks harvested in New Zealand. Marine Orn.. P. 133 in:. Close ), mostly for food but also for soap and oil. Recent research has focused on whether this harvesting is truly sustainable as long assumed (42 Moller, H., Cruz, J., Fletcher, D., Garrett, K., Hunter, C., Kitson, J., Lyver, P., Russell, B. and Scofield, P. (2000). Kia mau te tïtï mo ake tonu atu: goals, design and methods for a research project to assess the sustainabilty of a traditional harvest of Sooty Shearwaters Puffinus griseus by Rakiura Mäori. Marine Orn.. P. 137 in:. Close ). Some predation by alien fauna, including cats, rats, pigs and Wekas (Gallirallus australis) (43 Harper, G. (2006). Weka (Gallirallus australis) depredation of sooty shearwater/titi (Puffinus griseus) chicks. Notornis. 53(4): 318–320. Close ); natural predators have included Peregrine Falcons (Falco peregrinus) (44 Wynn, R. B., M. McMinn-Grivé, and A. Rodríguez-Molina (2010). The predation of Balearic Shearwaters by Peregrine Falcons. British Birds 103(6):350–353. Close ). Several thousand birds drown in gill nets in N Pacific each year and driftnets were formerly estimated to take 350,000 birds annually (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ). Elimination of introduced predators from breeding islands recommended, but it has been suggested that recent declines are associated with climate change (4 Brooke, M. (2004). Albatrosses and Petrels Across the World. Oxford University Press, Oxford, UK. Close ) and especially fisheries bycatch (45 Scofield, P. (2000). Declines in Sooty Shearwaters Puffinus griseus on their breeding grounds: the effects of bycatch or global warming? Marine Orn.. P. 146 in:. Close ) with, for example, total of 98% of 1231 dead procellarids recovered as bycatch and examined by researchers in New Zealand waters being this species (46 Uhlmann, S.S. and Jeschke, J.M. (2011). Comparing factors associated with total and dead sooty shearwater bycatch in New Zealand trawl fisheries. Biological Conservation. 144: 1859–1865. Close ). A mass mortality event was recorded in the coast of C Peru in 2010 (47 Ayala, L., Paz-Soldan, L. and Garate, P. (2013). A mass mortality event of sooty shearwaters (Puffinus griseus) on the central coast of Peru. Notornis. 60(2): 258–261. Close ).