DIOMEDEIDAE (20 species)

In the Northern Hemisphere there are 3 species, with vagrants from the Southern Hemisphere recorded. In the Southern Hemisphere, at least 11 species (including D. irrorata Waved Albatross) in 4 genera are generally recognized, although further splits have been suggested resulting in species status for each of the 24 known taxa (Robertson and Gales 1998). It should be noted here that calculations of distance matrices using cytochrome b sequence data indicate that many of the proposed splits are unsupported if a 1% DNA sequence divergence is used as a threshold (Penhallurick and Wink 2004; Penhallurick 2012). Chalmers et al (2009) carried out a phylogenetic analysis of all 24 taxa based on cytochrome b DNA sequences but included biological considerations when analysing taxa separated by small sequence distances. A similar approach is used herein; specific cases are discussed in the species accounts.
The only taxon not recorded with certainty in the Pacific Region is D. amsterdamensis Amsterdam Albatross (Roux et al 1983). This taxon was reported as longliner bycatch south of Tasmania in 1992 (Robertson and Gales 1998), but it now appears that the capture was in the Indian Ocean outside Australian territorial waters (Gales, in Christidis and Boles 1994). Birds recently (1999) photographed and measured off se Australia (Palliser: Aust Seabird Grp Newsletter 35:17) may be this species or juvenile D. c. antipodensis. It appears that immatures of the two taxa cannot be differentiated in the hand, and they may be more closely related than previously believed (Shirihai 2002). The taxon dabbenena has been recorded off se Australia, and thus probably occurs occasionally in the Tasman Sea.

Diomedea chionoptera Wandering Albatross
NOTE: The somewhat confused taxonomy of this species stems from disagreement over the provenance of the specimen described by Linnaeus 1758 as exulans. Medway (1993) concluded that the somewhat equivocal measurements cited by Edwards (referred to by Linnaeus) suggested a high latitude provenance, whereas others using the same Edwards data (Chris Robertson- see Penhallurick, BIRDING-AUS 30 Jun 2000) maintain that Gough I was the source of the specimen. Olmos (SEABIRD Oct 2000) pointed out that Dabbene (1926) added or corrected the origin of the specimen cited by Linnaeus to South Georgia; if this is substantiated, then indeed exulans applies to high latitude populations. It seems advisable based on these uncertainties to consider exulans indeterminate. In this case, chionoptera Salvin 1896 applies to high latitude populations, and becomes the specific epithet for the species, and dabbenena Mathews 1929 (spadicea is a nomen oblitum for the Gough I population) applies to Gough and Tristan populations. The remaining low latitude populations are amsterdamensis of the Indian Ocean and antipodensis and gibsoni on New Zealand subantarctic islands.
Burg and Croxall (2004) made a strong case based on genetic studies for separate specific status for high-latitude populations, the position followed here (as chionoptera). The status of the four low-latitude populations is unresolved. Burg and Croxall (2004) concluded that dabbenena is genetically separate from the New Zealand taxa antipodensis and gibsoni. Penhallurick (2012) suggested that amsterdamensis, because of its "high level of morphological differentiation (= extreme neotony)", should be retained for now as a species as described by Roux et al (1983). Burg and Croxall (2004) did not include amsterdamensis in their study; it is essentially indistinguishable from antipodensis (see for example Shirihai 2002). It seems best to separate the low-latitude populations into 3 species: dabbenena, amsterdamensis, and antipodensis, the latter including the subspecies antipodensis and gibsoni.

Breeds Macquarie I 12 prs (Baker et al 2002; Alderman et al 2005). At sea n to 20S, incl specimen New Caledonia (Barre and Dutson 2000). Breeders from South Georgia reach e as far as NZ (Tickell 2000; one banded Bird I, South Georgia, observed Stewart I Nov 1999; Seddon: Southern Bird #3, 2000), while s Indian Ocean breeders occur entire s Pacific n to about 20S (Tickell 2000), poss 10S off S. America.
D. chionoptera/D. antipodensis subsp? Max abundance e Tasman Sea May-Jun, NZ coastal waters Jun-Jul; "regularly seen at sea Kermadec Is" (Veitch et al 2004), in Humboldt Current n to 33S, occ to 10S. Cas Lord Howe I (5 recs May and (4) Sep-Oct, McAllan et al 2004), Norfolk I, New Caledonia (Jul, Sep, Barre and Dutson 2000), May-Oct Fiji, Jul-Nov Tonga. Acc Vanuatu (Dutson 2011), Tuamotu Is, Marquesas Is (DuPont 1976), Jul California, Japan.
D. chionoptera/D. epomophora/D. sanfordi? Acc Galapagos Is (2 recs, Swash and Still 2005).

D. antipodensis Antipodean Albatross

NOTE: Double (2006) and Burg and Croxall (2004) considered antipodensis and gibsoni a subspecies pair of D. antipodensis, the position adopted by the Taxonomic Working Group (TWG) of the Agreement on the Conservation of Albatrosses and Petrels (ACAP) (www.acap.aq).
D. a. antipodensis Breeds Antipodes Is 8600 prs, with 5180 prs yearly 1994-97 (Walker and Elliott 2005), Campbell I 5-10 prs, Chatham Is (Chatham and Pitt Is, 6 attempts 3 successful 2003-2009 Aikman and Miskelly 2004, Miskelly et al. 2006, 2008). At sea sw Pacific n to 25S, occasionally to Fiji and e (male non-breeders mostly Feb-Jul) to Humboldt Current (Walker and Elliott 2006). One near Austral Is Sep (Gaskin and Wood). Eggs mid-Jan to mid-Feb (Walker and Elliott 2005).
D. a. gibsoni Breeds Auckland Is 8000 prs, with 5831 prs breeding each year (Walker and Elliott 1999). At sea mostly in Tasman Sea between 30-55S, but many, mostly males, eastern NZ continental shelf and Chatham Rise (Walker and Elliott 2006). About 85% of the Diomedea that occur off the New South Wales coast are Gibson's Albatross (Milburn-post to Birding-Aus 2002). Eggs Jan.

D. dabbenena Tristan Albatross
Although probably indistinguishable at sea from D. antipodensis, tracking data (Birdlife International) show that the foraging range extends to southwest Australia and at least one bird banded on Gough Island has occurred off Wollongong, Australia (Battam, Birding-Aus 2012). This suggests that this taxon occurs at least in the western Tasman Sea.

D. epomophora Royal Albatross
NOTE: It has been proposed (Robertson and Nunn in Robertson and Gales 1998) that the 2 taxa of Royal Albatrosses be accorded specific status, and some current authors are doing so (eg Onley and Scofield 2007). The TWG of the ACAP has also accorded each specific status, but notes "This is clearly a case where more data are required. Phylogenetic, phylogeographic and population genetic data from each of the main breeding islands (Taiaroa Head and the Chatham, Campbell and Auckland Islands) are required and given the observed cases of hybridisation such data may be highly influential" (www.acap.aq). Mixed pairs occur SI and Auckland Is (see below; Robertson and Gales 1998), and cytochrome b studies show very little distance between the taxa (Penhallurick and Wink 2004). While plumage sequences differ significantly between the two forms, and age and gender classes are distinguishable at sea, Penhallurick (2012) ascribes this to ecophenotypic variation.
D. e. epomophora Breeds Auckland Is 100 prs including 2 mixed pairs with sanfordi in recently re-established population on Enderby I (Robertson and Gales 1998), Campbell I 13,000 prs (Imber 1999). At sea Jun-Aug n to 20S, mostly west Dec-Feb (juveniles) and east Jul-Sep (older age groups) coasts of S. America (Moore and Bettany 2005), but 10S off western S. America. This subsp. outnumbered sanfordi 9:1 off s. Chile Sep 2004 (Nicholls 2007). One banded NZ beach-wrecked New Caledonia Oct (Barre and Dutson 2000). Eggs Nov-Dec.
D. e. sanfordi Breeds Chatham Is: Sisters 2500 prs, Forty-Fours 4000 prs, NZ (SI: Taiaroa Head 15-30 prs including 5 known hybrids with epomophora; Robertson and Gales 1998). At sea Jun-Aug n to 20S, 10S off S. America; return circumpolar, with rapid migration NZ to S. America for non-breeding season then rapid return eastward (satellite tracking- Robertson and Nicholls 2000). Juv Oct ca 32-33S/165W (Gaskin and Wood). Acc New Caledonia (Dutson 2011). Eggs Nov-Dec.
epomophora/sanfordi subsp? Acc May s Tonga, Cook Is (imm Rarotonga Sep), Tuamotu Is (band recovered). Fiji rec considered incorrect (Watling 2001).

Phoebastria irrorata Waved Albatross
Breeds Galapagos Is (Espanola) 12,000 prs. At sea south and east to coast of S. America 4N-16S (Tickell 2000). Acc Cocos I (Montoya 2012). Eggs Apr-Jul.

P. albatrus Short-tailed (Steller's) Albatross
Breeds s Izu Is (Torishima) ca 1500 inds in 2001, up from only 10 in 1950 (Hasegawa); Ogasawara Is (Yomejima I, 1 pair Dec 2000 (SEABIRD); Mukojima I, 10 chicks translocated 2008; first egg laid from these birds Dec 2012 but apparently attempt unsuccessful); Hawaiian Is (Midway I: At least 16 individuals 1965-2009, several banded Torishima I, but no successful breeding and only one pair noted (Pyle and Pyle 2009); bred unsuccessfully 1993 (Robertson and Gales 1998), incl yellow-banded female pres and laying eggs every 2 yrs since 1993 but never mated (N Am Birds 56:120); nest with 2 eggs laid Oct 31-Nov 1, 2010 unsuccessful as result of fem-fem pairing- VanderWerf, Pyle; 2011- 2 prs, one with an egg; chick hatched- first ever away from Japanese territories (USFW); chick fledged again by same pair in June 2012 (ACAP). Kure Atoll: pr attempting nesting 2010, John Brodie-Good). At sea s to 20N ne Pacific mostly Jun-Nov, Aug-Jan further se. Cas Hawaiian Is (French Frigate Shoals, Laysan I, Kure, Pearl and Hermes, Kauai), although numbers are increasing; in 2012 there were "three birds ... on Kure Atoll, five on Midway Island, one on Laysan Island, and one on Tern Island (Am. Bird Conservancy). Acc Guadalupe I, Revillagigedo Is (San Benedicto). Hypo Mariana Is (Baker 1951). Eggs Oct-Nov.

P. nigripes Black-footed Albatross
Breeds nw Hawaiian Is (Kure and Midway e to Nihoa and Kaula, 50,000 prs); s Izu Is (Torishima) 1300 prs; Ogasawara Is (Mukojima) 1000 prs; ?Johnston I, Revillagigedo Is (San Benedicto 1 pr, Pitman and Ballance 2002; reported Clarion, Wanless et al 2009). Extirp as breeder Mariana Is, Wake (Pyle and Engbring 1985). At sea 18N-45N, incl n Mariana Is, cas n to 55N and s to 0. Absent breeding locations mid-Jul to mid-Oct (Pyle and Pyle 2009). Old reports of breeding on Marshall Is have been discounted (Amerson 1969; Tickell 2000). Birds from Midway I spend non-breeding season off Hokkaido (Brazil 1991). Acc NZ (Jul SI), Guadalupe I, e of Galapagos Is. Eggs Nov-Dec.

P. immutabilis Laysan Albatross
Breeds total 1,300,000-2,100,000 inds or 558,000 prs nw Hawaiian Is (Kure e to Kauai, Niihau, Nihoa, Moko Manu; about 2/3 at Midway), Wake I (Pyle and Pyle 2009), s Izu Is (Torishima 1000 prs, Tickell 2000), Ogasawara Is (Mukojima 20 prs, Robertson and Gales 1998), Guadalupe I 50 prs, Revillagigedo Is 50 prs (Clarion 40 prs 2002/3, Wanless et al 2009; San Benedicto 12 prs, Pitman and Ballance 2002). Extirpated Johnston I (Pyle and Pyle 2009). At sea 15N-55N, incl Mariana Is (Reichel and Glass 1991), Caroline Is (Pohnpei, Penhallurick 2003). Tracking suggests birds from NW Hawaiian Is and SE Hawaiian Is forage in different areas of the Pacific (Pyle and Pyle 2009). Marked northward shift non-breeding season (King 1974); absent breeding locations late Jul-mid Oct (Pyle and Pyle 2009). Cas s to 8N, incl n. Marshall Is (Amerson 1969). Acc Solomon Is (Makira) Sep 1965 (banded at Midway I as juv Mar 1965, Robbins and Rice in Tickell 2000); Norfolk I Oct 1985 and Aug 1986 (Tickell 2000, Moore 1999; a previous record not accepted by RAOU, Christidis and Boles 1994), NZ (Aug 1986; Dec 1995 NI, Medway 2000). Eggs Nov-Dec.

Thalassarche melanophris Black-browed Albatross

NOTE: This taxon and T. impavida have recently been considered separate species. Although Penhallurick and Wink (2004) retain these as a subspecies pair based on their relatively close genetic distance, there is biological evidence for species status. Mixed pairs occur along with pure pairs on Campbell I, but this may be a result of the low numbers of this taxon relative to the large numbers of impavida present and the finding that most dark-eyed birds present are males; the presence of pure pairs of melanophris amongst large numbers of impavida suggests assortative mating (Moore et al 1997, 2001). Fledging success of mixed pairs is lower than that of pairs of impavida (Moore et al 1997).
Moore et al (2001) found two genetically distinct groups within melanophris on Campbell I; "typical" birds, and Falkland Is birds; status of these taxa is unresolved, although Burg and Croxall (2001) showed that Falklands birds differ genetically from all other populations of the species. Further, Alderman et al (2005) confirmed this finding, and concluded that range expansion of Falklands haplotypes into the Pacific has occurred, with secondary contact between these haplotypes and those of impavida on Campbell I and Macquarie I.
Waugh et al (2000) showed that foraging strategy differs between impavida at Campbell Island and nominate birds at South Georgia and Kergulen, the former including oceanic forays up to 2000 km, the latter strictly neritic.

Breeds Macquarie I 46 prs (Baker et al 2002), Antipodes Is (Bollons I) 120 prs, Snares Is (first recorded 1984) 1 pr, Campbell I (first recorded 1975) 30 prs. At sea n to 10S off S. America probably all from S. American breeding islands; also n and e to Tasman Sea, where cas Norfolk I, Lord Howe I (3 recs: May, Sep, Oct, McAllan et al 2004), esp juvs Nov-Jan, probably birds from Macquarie I and breeding islands west to S. Georgia (Tickell 2000). One Oct ca. 31-32S/160W (Gaskin and Wood). Acc to between Hawaiian Is and Line Is (listed as melanophris by Penhallurick 2003), Galapagos Is. Eggs Sep-Oct. Breeds annually.

T. impavida Campbell Albatross
Breeds Campbell I 26,000 prs. At sea n in sw Pacific rarely to 20S incl New Caledonia (this sp or poss melanophris, Dutson 2011), Aug Fiji, Tonga, Samoa, Cook Is, ca 32-33S/165W Oct (Gaskin and Wood), Marquesas Is, Tuamotu Is, Pitcairn Is (records at these two listed as impavida by OSNZ 2010) and e to 140W (Tickell 2000). Peak NZ (Cook Strait) Jul-Aug. Eggs Sep-Oct. Breeds annually.

Shy Albatross
NOTE: Some authors consider all 4 taxa separate species: White-capped (Auckland Shy; steadi), (Tasmanian) Shy (cauta), Salvin's (salvini), and Chatham (eremita). Genetic studies by Abbott and Double (2003) and Penhallurick and Wink (2004) indicate that the taxa could be allocated to 2 species, one including cauta and steadi, and the other including eremita and salvini. Data in Abbott and Double (2003) show sufficient divergence between salvini and eremita to warrant specific status, although Miskelly et al (2000) discuss the presence of incubating eremita and apparent hybrids between eremita and salvini at the Snares Is. Abbott and Double (2003) considered cauta and steadi to be insufficiently divergent to warrant specific status, although treatment as separate species based on bill coloration and clear mensural differences is suggestive; there is no detectable gene flow between the taxa, although it has been suggested that the Tasmanian colonies were initiated by birds from the populations of steadi (Double et al 2003; Double 2006). The TWG of ACAP (www.acap.aq) separates the taxa into 4 species, noting that all are genetically diagnosable and that feeding ranges are essentially separate, but ignores evidence of interbreeding (see above). Oddly, the most difficult pair to separate in the field, cauta and steadi, may have less gene flow between them than salvini and eremita. Nevertheless, the decision of the TWG is followed here, if for no other reason than taxonomic stability as suggested by the TWG: "Given ... a desire for a stable taxonomy ... we recommend that these taxa continue to be recognised as separate species." (www.acap.aq).

T. steadi White-capped Albatross
Breeds Auckland Is 70,000-83,100 prs (Taylor 2000), Antipodes Is 20-50 prs, Chatham Is (Forty-fours 1 pr since 1991, Aikman and Miskelly 2004; Miskelly et al 2006). At sea n to 20S, apparently e to S. America and northward on occasion across equator (1 rec N. America Sep 1951 off Washington, Cole 2000, but see Slipp 1952; photo of Peru at http://www.birding-peru.com/upload/reports/White-capped-Albatros1.jpg). Ad (cauta/ steadi) at Macquarie I Oct 2002 (R. Clarke) and Nov 2006 (Hobcroft). Eggs Sep-Oct.

T. cauta Tasmanian Albatross
At sea sw Pacific, e to NZ. Occurs off e S. America, probably arriving there westward via S. Atlantic; no evidence for eastward movement to S. America. Brothers et al (1997) showed subadults move westward as far as South Africa and adults remain in Australian waters. Acc NZ (NI Jul 1989, OSNZ 2010). Three recs N. America: Aug 1999 off California, Jan 2000 off Washington (possibly same bird); also poss same bird an imm Oct 1996 off Oregon (Cole 2000). Eggs Nov-Dec.

T. salvini Salvin's Albatross
Breeds Snares Is 650 prs (Miskelly et al 2000), Bounty Is 30,750 prs (Taylor 2000), Chatham Is (Pyramid 2 prs? Aikman and Miskelly 2004; Miskelly et al 2006). Attempted breeding with eremita at Snares Is and Chatham Is (see eremita, below). At sea (mostly juvs-Harrison 1983) n to 20S, 6S off S. America. Acc (this subsp. or poss eremita) off N. America Jul 2000; a subadult was on Midway Atoll 8 Apr 2003 (Robertson et al 2005); one at Diego Ramirez 56S (Arata 2003). Eggs Sep-Oct.

T. eremita Chatham Albatross
Breeds Chatham Is (Pyramid Rock) 4000 prs; attempted breeding with salvini on Western Chain, Snares Is (Miskelly et al 2000) and also at Pyramid, Chatham Is, 2003 (Miskelly et al 2006). At sea eastward to Humboldt Current Apr-Aug, return more northerly (satellite tracking- Robertson et al 2000; Tickell 2000; Spear et al 2003; Latham et al 2004); Oct ca 37S/178E ne of NZ (Gaskin and Wood). Also occasionally in Tasman Sea. Eggs Aug-Oct.

T. chrysostoma Grey-headed Albatross
Breeds Macquarie I 78 prs (Baker et al 2002), Campbell I 6000 prs (Waugh et al 2000). Seen ashore Antipodes Is 1950 (Tennyson et al 2002). At sea Jun-Nov n to 35S, possibly 15S off S. America (an adult from South Georgia to Drake Passage and north off Chile; South Georgia juvs eastward to NZ, Tickell 2000; S. Georgia birds circumvent Southern Ocean, esp males, one male 22,000 km in 46 days, 3 birds circumnavigated twice in 18 months, Coxall). Campbell I breeders forage Tasman Sea (Tickell 2000). Acc Society Is (Tahiti, Enticott and Tipling 1997). Eggs Oct. Breeds biennually if successful; if not, returns following year.

T. chlororhynchos Yellow-nosed Albatross
NOTE: Regarding status of these taxa, the TWG of ACAP (www,acap.aq) stated: "Clearly this is a case where more data are needed and further data may require this decision [to retain both as species] to be revisited. Phylogenetic, phylogeographic and population genetic data from each of the main breeding islands (Tristan, Gough, Prince Edward, Crozets, and Amsterdam Island) are required. The at-sea ranges of the two taxa overlap off southern Africa ..., and chlororhynchos have been recorded visiting Amsterdam Island ..., so the possibilities of contemporary migration and inter-breeding need to be explored." Although the taxa differ morphologically, carteri currently breeds in small numbers at Pyramid, Chatham Is (see below) and chlororhynchus, although rare in New Zealand waters, has visited the Chatham Is also (see below) as well as Amsterdam I. The comments of the TWG, along with the potential for these taxa to eventually interbreed, suggest retention as subspecies.
T. c. carteri (bassi of some authors, but see OSNZ 1990, Robertson 2002). At sea Apr-Dec (juvs peak Sep-Oct) ne to n NZ (NI) and 26S, unrecorded e of Chatham Is. Acc Jan Snares Is (Miskelly et al 2001). One pair nesting at Chatham Is (Pyramid) since Nov 1998 (Aikman and Miskelly 2004; Miskelly et al 2006).
T. c. chlororhynchos Cas ne to n NZ: 3 recs, incl single birds at Chatham Is (Sisters Is) Jan 1975 (Robertson 1975), Sep 1976 (Miskelly et al 2006), and Jan 1996 (Miskelly et al 2006).

T. bulleri (Southern) Buller's Albatross
NOTE: This taxon and the northern form platei (see below) are considered conspecific by some authors, but the 3-month differential in laying dates between the two taxa suggests specific status. Despite this significant biological factor, the two taxa were retained as subspecies by Double (2006) and TWG of ACAP (www.acap.aq), citing the paucity of data that would allow elevation to specific status.
Breeds Solander Is 4912 prs (Sagar and Stahl 2005), Snares Is 8713 prs (Sagar and Stahl 2005). Extended tracking data from the Snares population show that all are off the coast in Nov, migrating there Aug-Oct. Return is Dec-Feb westward to NZ. During the breeding season, foraging birds were mainly near and south of NZ, with expansion as the breeding season went on. During Aug the range began to contract as birds moved east to South America (Sagar et al 2010). At sea breeding season n to 41S around NZ (SI, Stahl and Sagar 2000a, 2000b); Jun-Aug n to 12S, apparently migrating to/from the Humboldt Current (one 7-8 years old not yet breeding banded as chick at Snares Is recovered Oct at 12S 105W, Warham 1982, Tickell 2000; one ca. 31-32S/160W Oct (Gaskin and Wood); one rec Kermadec Is (this form? Jul Raoul, Reed 1973)); recorded New Caledonia (one record, this subsp.? http:/inpn.mnhn.fr; Dutson 2011); Chatham Is Jan 1996 (Miskelly et al 2006). Suggested (Harrison 1983, Enticott and Tipling 1997) that most sedentary, but this taxon absent between breeding seasons from Snares Is, returning around Dec 1 (Miskelly et al 2001) and Solander I (Stahl and Sagar 2000b), and most disperse outside Australasian seas between breeding seasons (Stahl et al 1998). Eggs Jan-Feb. Breeds annually.

T. platei Pacific (Northern Buller's) Albatross
NOTE:It has been suggested that the holotype of platei was actually an immature bulleri (Robertson and Nunn, in Robertson and Gales 1998), but there has been no evidence published to support this (OSNZ 2010).
Breeds Chatham Is (Forty Fours 16,000 prs, Sisters 2000 prs); NZ (Three Kings Is: Rosemary Rock 15 prs). At sea breeding season in vicinity (Stahl et al 1998); Jun-Sep n to 20S, to 12S off Peru (whether Humboldt Current birds are indeed this taxon questioned by Jaramillo 2003). Eggs Oct-Nov. Breeds annually.

Phoebetria fusca Sooty Albatross
At sea Feb-Nov northeastward to w Tasman Sea (recs s of Australia), Macquarie I, Feb 1991 Auckland Is, Nov 1993 Pukaki Rise, Nov 1995 Antipodes Is, Dec 2006 Chatham Is, NZ (SI Jun 1997; Nov 2004, Watola), once extreme se Pacific (Challenger Plateau 1994, Enticott and Tipling 1997; Tickell 2000). Breeds biennually if successful; if not, returns following year.

P. palpebrata Light-mantled Sooty Albatross
Breeds Auckland Is 5000 prs, Campbell I 1600 prs, Antipodes Is 200-300 prs (Taylor 2000), Macquarie I 5000 prs. At sea Jun-Aug n to 35S, 20S off S. America. Cas Kermadec Is. Acc New Caledonia (Lifou, Dutson 2011), Marquesas Is, Jul 1994 California.

HYDROBATIDAE (14 species)

Recent evidence has demonstrated that the storm-petrels are polyphyletic, separating into northern and southern hemisphere clades (see discusssion in Christidis and Boles 2008). This is followed here, with Hydrobatidae used for northern storm-petrels and Oceanitidae for southern storm-petrels, although some authors separate these only at the sub-family level as Hydrobatinae and Oceanitinae). Recent genetic studies (for example Penhallurick and Wink 2004, see Christidis and Boles 2008) place these families as sister clades to Diomedeidae.
The southern forms of storm-petrel are generally considered to consist of 5 genera, Oceanites, Garrodia, Pelagodroma, Fregetta (including Pealeornis), and Nesofregetta, and Penhallurick and Wink (2004) demonstrated that northern forms are paraphyletic also, falling into four groups that are as genetically distinct as the five southern groups. Because the generic positions of some species in the classification of Penhallurick and Wink (2004) remain unclear, Christidis and Boles (2008) included Oceanodroma (=Cymochorea herein) and Halocyptena in Hydrobates. The generic names for these groups are shown below in the respective species accounts.

Hydrobates furcatus Fork-tailed Storm-Petrel

NOTE: Penhallurick and Wink (2004) showed with cytochrome b studies that Oceanodroma is paraphyletic at the generic level, consisting of this group, Hydrobates, and the 3 groups shown below, Cymochorea, Halocyptena, and Thalobata. This taxon (H. furcatus) groups with Hydrobates according to cytochrome b studies by Penhallurick and Wink (2004); as Oceanodroma is junior to Hydrobates, the generic name for this group becomes the latter.
H. f. furcatus At sea nw Pacific, incl Iwo Is, Marcus I (=Minamitorishima) (Brazil 1991).
H. f. plumbeus At sea ne Pacific s Sep-May to 35N. Acc Hawaiian Is (Scott et al 2001, Pyle 2002).

Cymochorea leucorhoa Leach's Storm-Petrel
NOTE: Cymochorea is the earliest available name for this group (Penhallurick and Wink 2004). Huntington et al (1996) placed beali with leucorhoa and willetti with chapmani, as suggested by Power and Ainley (1986) and followed here. Howell et al (2009) and Howell (2012) presented evidence for separation as full species the two Guadalupe I breeding populations as O. socorroensis Townsend's Storm-Petrel and O. cheimomnestes Ainley's Storm-Petrel.
C. l. leucorhoa including beali Eggs May-Jun. At sea n. Pacific s to 12S mostly in c. Pacific 170W-175E, south to 27.3S eastern Pacific (Spear and Ainley 2007); largest numbers Oct-Mar, but significant numbers (immatures?) May-Aug (King 1974, Huntington et al 1996, Spear and Ainley 2007); incl Mariana Is (Reichel and Glass 1991), Marshall Is (3 specs, Huber 1971; Pyle and Engbring 1985), Kiribati (Phoenix Is, Line Is, Pratt 1987), Hawaiian Is, Marquesas Is (this subsp?) and Galapagos Is (large concentrations west of Galapagos Is, esp Nov-Mar, appear to be birds often referred to as beali, King 1974). Cas Vanuatu (west of Vanuatu, Dutson 2011), NZ (NI Apr 1978, Aug 1922, Aug 1978, Oct 1998, Watola, incl Chatham Is where 2 prospecting Rabbit I Nov-Dec 1980, Imber and Lovegrove 1982), Cocos I (this subsp? Montoya 2003).
C. l. chapmani including willetti. Eggs May-Jun. At sea Oct-Apr e. Pacific as for leucorhoa (Huntington et al 1996), but possibly closer to coast than leucorhoa/beali (King 1974).

C. socorroensis Townsend's Storm-Petrel
Breeds 7000 inds Guadalupe I (Islote Afuera, Islote Negro, Howell et al 2009). Eggs late May-Jun. At sea Oct-Apr e. Pacific (Howell 2012, Huntington et al 1996); King (1974) gave range between 10N and 35N, with few sightings >250 miles from the coast.

C. cheimomnestes Ainley's Storm-Petrel (including kaedingi).
Breeds "a few thousand" Guadalupe I (Islote Negro, Islote Afuera, Gargoyle Rock; most of this population have white rumps- Howell and Webb 1995; Howell 2009). Eggs Oct-Nov. At sea Oct-Apr e. Pacific as for leucorhoa (Huntington et al 1996), but generally foraging further south May-Sep from breeding site than dark-rumped socorroensis, however (see discussion in Ainley 1980, Howell et al 2009, Howell 2012). Dark-rumped birds collected at 0 and 140W in Jun and at 9N and 140W in Apr some 5000km from the mainland (Spear and Ainley 2007) may have been this taxon.

C. macrodactyla Guadalupe Storm-Petrel
Extinct. Bred formerly Guadalupe I.

C. monorhis Swinhoe's Storm-Petrel

NOTE: Considered by some authors conspecific with C. leucorhoa Leach's Storm-Petrel.
At sea nw Pacific breeding season, migrates Sep-Apr to ne Indian Ocean. Reg vis nw. Hawaiian Is?

C. tristrami Tristram's Storm-Petrel
Breeds s Izu Is, Iwo Is, ?Ogasawara Is (Harrison 1990; extinct Torishima, Penhallurick 2003), ?Mariana Is (Pyle and Engbring 1985; Reichel and Glass 1991 consider occ hypo only), Hawaiian Is (6,000 prs, Pyle and Pyle 2009, nw islands e to Nihoa). Eggs Jan. At sea in vicinity in cw Pacific, but no recs Hawaiian Is May-Aug; primary dispersal likely west and north (Pyle and Pyle 2009).

C. markhami Markham's Storm-Petrel
At sea e Pacific between 17N and 30S and west to 118W on the equator (Spear and Ainley 2007, King 1974); westernmost birds >500 km offshore mostly sub-ads (Spear and Ainley 2007). Cas Clipperton I, Galapagos Is. Acc Cocos I (Montoya 2008a).

Halocyptena microsoma Least Storm-Petrel

NOTE: The earliest available name for this group is Halocyptena (Penhallurick and Wink 2004).
At sea off California (Aug-Oct, McGrath and Feenstra 2005) and Mexico, s to Ecuador; 35N to 9S (Spear and Ainley 2007). Cas up to 600 miles offshore (King 1974), incl Revillagigedo Is, although all within 327 km of mainland (Spear and Ainley 2007).

H. tethys Wedge-rumped (Galapagos) Storm-Petrel
H. t. tethys Breeds 400,000 inds Galapagos Is (Genovesa, Pitt, Harris 1969), but total population est up to 1,136,900 in austral spring (Spear and Ainley 2007). Eggs mostly May-Jun. At sea n to Panama, cas to 29 N off Mexico (Guadalupe I, Revillagigedo Is, Jehl and Parkes 1982), Cocos I (Montoya 2003), s to 20S; most were recorded 20n to 20s and >250 km from mainland Americas west to 176W (Spear and Ainley 2007), incl Palmyra area (Aug, Force and Webb) and another photographed 350 mi s. of Fanning Island Oct 2011 (fide Walther). One well-described 9 Oct 2010 325 km s. of South Point, Hawaii (Dawn Breese, fide Pyle).
H. t. kelsalli At sea 32N to 30S and within 500 km of mainland (Spear and Ainley 2007). Acc Jan California (Roberson 1980; McGrath and Feenstra 2005). Cas (this subsp?) southern California Aug-Oct (McGrath and Feenstra 2005).

H. matsudairae Matsudaira's Storm-Petrel
Breeds Iwo Is (Kitaiwojima, Minamiiwojima), Ogasawara Is; 20,000 inds Bird Life Intl. Eggs Jan-Feb. At sea vicinity during breeding season Jan-Jun. At sea s of breeding location between 30N and New Guinea, possibly ne of New Guinea. Unc migrant Palau. Vis Mariana Is (most Apr-Jul, Wiles et al 2000, Kessler 1999, Reichel and Glass 1991). Cas (reg?) Solomon Is (ca 300 km ne Buka July, 22 mi ne Nuguria, Hadden 2004a; multiple sightings Bismarck Archipelago late Jul-early Aug 2008 Shirihai 2008). Acc Fiji May 2009 (Hadoram and Pym et al 2009). Hypo Caroline Is (Jul between Kosrae and Pohnpei, Pyle and Engbring 1985).

H. melania Black Storm-Petrel
At sea e Pacific California (late Apr-Oct, McGrath and Feenstra 2005) to Peru (38N-13S, Spear and Ainley 2007). Sightings up to ca. 900 miles offshore at 8N/120W (King 1974), but all recorded were within 360 km of mainland (Spear and Ainley 2007). Cas Revillagigedo Is. Acc Cocos I (Montoya 2008b), Galapagos Is (2 recs, Swash and Still 2005).

H. homochroa Ashy Storm-Petrel
Total pop 6500 inds (McGrath and Feenstra 2005). At sea n California to Mexico, 38.5-32 N and within 260 km of mainland (Spear and Ainley 2007). Whether this species occurs >200 mi from mainland is doubtful; limits of 7-47N and up to 480 miles offshore (King 1974) considered mis-identifications of dark-rumped Leach's Storm-petrels (Spear and Ainley 2007).

H. hornbyi Ringed (Hornby's) Storm-Petrel
At sea Jul-Nov off s Peru and n Chile between 25S and 35S, further n Aug-Dec, to Equator (overall 3S-32S, Spear and Ainley 2007). Few >200 miles offshore (King 1974); furthest offshore 481 km (Spear and Ainley 2007). Acc Aug off California.

Thalobata cryptoleucura Pacific (Band-rumped) Storm-Petrel

NOTE: Thalobata is the only available name for this group (Penhallurick and Wink 2004), traditionally considered monotypic as castro, but several recent studies indicate that more than one species is involved: according to Smith et al (2007), "Despite previous classification as a single, monotypic species, fixed haplotype differences occurred between Atlantic and Pacific populations, and among all Pacific populations. In addition, Cape Verde and Galapagos birds formed distinct clades, estimated to have diverged from all other populations at least 150,000 years ago." Boyd discusses the case for treating Pacific populations as a distinct species consisting of 3 subspecies involving the 3 breeding populations (Galapagos Is, Hawaiian Is, Japan). This treatment is followed here.
Reports of this species at sea near New Caledonia (between Grande Terre and Lifou Oct 1998, Barre and Dutson 2000; 10 birds 270 miles n. of Guadalcanal Dec 2008, MacKiernan; 7 off west coast of Grand Terre 3-4 Apr 2013, John Brodie-Good) and Solomon Is (Mar Bougainville, Hadden 2004a) may be referable to T. C. kumagai, which breeds in Japan.

T. c. cryptoleucura Breeds Hawaiian Is (Kauai 171-221 prs Pyle and Pyle 2009, Maui, Hawaii, but nesting sites unknown). Eggs May? (Pyle and Pyle 2009). At sea vicinity, possibly south in fall to about 10S and east to 160W (Spear and Ainley 2007), incl Marshall Is (spec Apr-May, Huber 1971).
T. c. bangsi Breeds Galapagos Is 15,000 prs, but estimates up to 475,700 in austral fall (Spear and Ainley 2007). Two differently-timed nesting populations with apparently no genetic interchange (Spear and Ainley 2007); Boyd makes the case that these are not sympatric merely because they breed at the same location without gene flow and therefore would be separate species, but merely allopatric forms (separated temporally) that are not yet differentiated to the species level. Eggs Feb-Mar and Oct-Nov. At sea vicinity, apparently foraging within 1000 km of breeding sites; limits were 25N and 27S and west to about 115W (Spear and Ainley 2007), including Revillagigedo Is (Penhallurick 2003). Acc Cocos I (Montoya 2008a).