Chapter IV: Part 4

_Characters._--Adult: A large sea bird with plumage of variable
color, mainly white or partly buff with black primaries and
black-tipped secondaries, or grayish or brownish with white or
grayish tail; throat blackish; face blue or green; bill bluish and
lighter at tip; legs and feet red.

Immature: Resembles adult, but often wholly brownish, lighter
ventrally; bill blackish; feet yellowish red. Immature resembles
that of _S. leucogaster_.

_Nesting._--Morrison obtained a male nestling at Bikini on May 3,
1946.

_Specimens examined._--Total number, 10 (3 males, 7 females) from
Marshall Islands, USNM--Bikini (April 28, May 1, 2, 3).

_Remarks._--The writer saw several birds approximately 20 miles east of Eniwetok on January 7, 1945. Morrison obtained a series of birds at Bikini in April and May, 1946. Murphy (1936:861-870) presents a wealth of information concerning the bird. He points out the need for a better understanding of the plumages of the adult birds and gives evidence that the birds of different colors may occur within the same population. He describes the Red-footed Booby as nesting in trees and shrubs. This type of nesting environment is present at many of the islands in Micronesia.

=Sula leucogaster plotus= (Forster)

Brown Booby

_Pelecanus Plotus_ Forster, Descr. Anim., ed. Licht., 1844, p. 278.
(Type locality Near New Caledonia.)

_Dysporus sula_ Hartlaub, Proc. Zool. Soc. London, 1867 (1868), p.
831 (Pelew); Hartlaub and Finsch, Proc. Zool. Soc. London, 1868,
pp. 9, 118 (Pelew); _idem_, Proc. Zool. Soc. London, 1872, p. 90
(Pelew); Finsch, Journ. Mus. Godeffroy, 8, 1875, pp. 6, 47
(Palau); _idem_, Proc. Zool. Soc. London, 1880, p. 577 (Ruk);
Hartert, Novit. Zool., 7, 1900, p. 11 (Ruk).

_Sula fusca_ Finsch, Ibis, 1880, p. 218 (Taluit).

_Sula leucogastra_ Salvadori, Ornith. Papuasia, 3, 1882, p. 423
(Pelew, Carolinis); Wiglesworth, Abhandl. und Ber. Zool. Mus.
Dresden, no. 6, 1890-1891 (1891), p. 72 (Pelew, Ruk, Marshalls);
Oustalet, Nouv. Arch. Mus. Hist. Nat. Paris, (3), 8, 1896, p. 63
(Palaos, Mariannes, Marshalls, Carolines); Hartert, Novit. Zool.,
5, 1898, p. 68 (Marianne).

_Sula sula_ Ogilvie-Grant, Cat. Birds British Museum, 26, 1898, p.
436 (Asuncion, Pelew); Seale, Occ. Papers Bernice P. Bishop Mus.,
1, 1901, p. 24 (Guam); Safford, Osprey, 1902, p. 66 (Mariannas);
_idem_, The Plant World, 7, 1904, p. 267 (Guam); _idem_, Contr. U.
S. Nat. Herb., 9, 1905, p. 80 (Guam); _idem_, Guam, 1912, p. 19
(Guam); Prowazek, Die deutschen Marianen, 1913, p. 100 (Marianen);
Takatsukasa and Kuroda, Tori, 1, 1915, p. 50 (Marianne); Cox,
Island of Guam, 1917, p. 22 (Guam); Uchida, Annot. Zool. Japon., 9,
1918, pp. 487, 493 (Sea off Mariana Islands).

_Sula leucogaster plotus_ Kuroda, in Momiyama, Birds Micronesia,
1922, p. 34 (Pelew, Ruk, West Faiu, Uracas, Saipan, Marshalls);
Yamashina, Tori, 7, 1932, p. 407 (Medinilla); Hand-list Japanese
Birds, rev., 1932, p. 185 (Uracas, Pagan, Medinilla, Saipan, Truk,
West Fayu, Grimes, Marshalls); Hand-list Japanese Birds, 3d ed.,
1942, p. 208 (Uracas, Pagan, Medinilla, Saipan, Grimes, West Fayu,
Truk, Marshalls); Baker, Smithson. Misc. Coll., vol. 107, no. 15,
1948, p. 41 (Rota, Guam, Truk).

_Geographic range._--Throughout tropical Pacific area and south to
Australia. In Micronesia: Mariana Islands--Asuncion, Uracas, Pagan,
Medinilla, Saipan, Rota, Guam; Palau Islands--exact locality
unknown; Caroline Islands--Grimes, West Fayu, Truk, Kusaie;
Marshall Islands--Jaluit, Eniwetok.

_Characters._--Adult: A heavy sea bird dark brown except for white
lower breast, belly, under tail, and auxillars; bill heavy and
light bluish; face, gular pouch and feet greenish yellow.

Immature: Resembles adult, but lower breast, belly and under tail
mottled with brown; feet light yellow.

_Measurements._--Two adult males (Rota, Guam) measure: wing 386,
408; tail 194; exposed culmen 93, 98; tarsus 45, 49; two adult
females (Rota, Kusaie): wing 380, 487; tail 193, 217; exposed
culmen 94, 99; tarsus 45, 50.

_Weights._--The author (1948:41) records one immature female from
Rota weighing 1042 grams.

_Specimens examined._--Total number, 6 (3 males, 3 females), as
follows: Mariana Islands, USNM--Rota, 3 (Oct. 24); AMNH--Guam, 1
(July 23); Palau Islands, AMNH--exact locality not given, 1 (Dec.
1); Caroline Islands, AMNH--Kusaie, 1 (April 19).

_Nesting._--Few records have been published concerning nesting of
the Brown Booby in Micronesia. Yamashina (1932a: 407) reports the
taking of 12 eggs at Medinilla in the Mariana Islands on February
19, 1931. At Palau, Coultas (field notes) obtained reports that the
bird nests at Kiangat, a small islet north of Babelthuap.

_Parasites._--Uchida (1918:487, 493) obtained bird lice
(Mallophaga), _Menopan brevipalpe_ and _Lipeurus potens_, from the
Brown Booby from the "sea off Mariana Islands."

_Remarks._--The Brown Booby has not been found abundantly by observers in the Micronesian area. Coultas and Kubary, who spent considerable time in this region, observed the bird at only a few of the islands. Probably the bird does not nest abundantly in Micronesia, although small colonies may be present. The NAMRU2 party observed a flock of twelve brown boobies on high cliffs at Taipingot Peninsula at Rota on October 24, 1945. Birds were seen also at Guam in May, July and November, 1945, and at Truk in December of the same year. Coultas obtained a single specimen at Kusaie; the natives told him that it was not a resident of the island. The writer observed several Brown Boobies approximately twenty miles east of Eniwetok in the Marshall Islands on January 7, 1945. These were in the company of other sea birds.

=Phalacrocorax melanoleucus melanoleucus= (Vieillot)

Little Pied Cormorant

_Hydrocorax melanoleucos_ Vieillot, Nouv. Dict. Hist. Nat., 8,
1817, p. 88. (Type locality, "Australasie," restricted to New South
Wales.)

_Carbo melanoleucus_ Hartlaub and Finsch, Proc. Zool. Soc. London,
1868, pp. 9, 118 (Pelew); _idem_, Proc. Zool. Soc. London, 1872,
pp. 90, 114 (Pelew).

_Graculus melanoleucus_ Finsch, Journ. Mus. Godeffroy, 8, 1875, p.
48 (Pelew).

_Microcarbo melanoleucus_ Salvadori, Ornith. Papuasia, 3, 1882, p.
410 (Pelew); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden,
no. 6, 1890-1891 (1891), p. 72 (Pelew).

_Phalacrocorax melanoleucus_ Ogilvie-Grant, Cat. Birds British
Mus., 26, 1898, p. 398 (Pelew); Nehrkorn, Kat. Eiers., 1899, p.
235 (Palau); Takatsukasa and Kuroda, Tori, 1, 1915, p. 50 (Pelew);
Uchida, Annot. Zool. Japon., 9, 1918, p. 486 (Palau).

_Ph[alacrocorax] melanoleucos_ Reichenow, Die Vögel, 1, 1913, p.
127 (Palauinseln).

_Microcarbo melanoleucus melanoleucus_ Kuroda, in Momiyama, Birds
Micronesia, 1922, p. 35 (Pelew).

_Microcarbo melanoleucus melvillensis_ Mathews, Syst. Avium
Australasianarum, 1, 1927, p. 228 (Pelew); Hand-list Japanese
Birds, rev., 1932, p. 186 (Babelthuap, Koror).

_Haliëtor melanoleucos melanoleucos_ Peters, Check-list Birds
World, 1, 1931, p. 93 (Pelew).

_Phalacrocorax melanoleucus melanoleucus_ Mayr, Amer. Mus. Novit.,
no. 486, 1931, p. 5 (Pelew); Amadon, Amer. Mus. Novit., no. 1175,
1942, p. 2 (Palau); Mayr, Birds Southwest Pacific, 1945, pp. 50,
284 (Palau, Marianas); Baker, Smithson. Misc. Coll., vol. 107, no.
15, 1948, p. 41 (Palau).

_Phalacrocorax melanoleucos melvillensis_ Hand-list Japanese
Birds, 3d ed., 1942, p. 207 (Pagan, Babelthuap, Koror, Angaur).

_Geographic range._--Tasmania, Australia, Lesser Sunda north
through Melanesia to Palau Islands. In Micronesia: Palau
Islands--Babelthuap, Koror, Garakayo, Ngabad, Peleliu, Anguar.

_Characters._--Adult: A small cormorant with upper parts black
with dull greenish gloss; under parts white except vent and under
tail-coverts which are sooty-black.

_Measurements._--The author (1948: 41) gives the following
measurements of two adult females from Peleliu: wing, 220 and 222;
tail, 153 and 157; culmen from notch of suture between maxilla and
quadratojugal bones, 35 and 36.

_Specimens examined._--Total number, 15 (1 male, 12 females, 2
unsexed), as follows: Palau Islands, USNM--Peleliu, 6 (Aug. 27,
Sept. 7, 10, 16); AMNH--exact locality not given, 9 (Nov. part).

_Nesting._--Nehkorn (1899:235) recorded eggs taken at Palau. Some
of the specimens obtained by Coultas in November, 1931, had swollen
gonads. The author found no evidence of nesting in August and
September, 1945, in the southern Palaus.

_Food habits._--The author (1948: 41) found small fish in the
stomachs of birds taken in August and September. The contents of
each stomach averaged approximately 3 cc. in volume.

_Parasites._--Uchida (1918:486) found the bird louse (Mallophaga),
_Lipeurus subsetosus_, on the Little Pied Cormorant from Palau.

_Remarks._--The Palaus mark the northernmost point of range of the Little Pied Cormorant. It does not occur in the Philippines and must have reached Palau from the New Guinea region. It is unknown at Yap and other "high" islands in the Carolines. A sight record of this species at Pagan in the northern Marianas, made by Orii and reported in the Hand-list of Japanese Birds (Hachisuka _et al._, 1942:207), may be questioned. Amadon (1942:1) has studied the races of this species and points out that there is little geographic variation in the species; it is divisible into three subspecies. One of these is confined to New Zealand. Another occurs only on Rennell Island, Solomons. The six specimens taken by the NAMRU2 party at Peleliu included only two adults, whose measurements are within the range of those studied by Amadon.

The NAMRU2 party found the birds numerously in the southern Palaus in 1945. Birds were concentrated in the areas of mangrove swamp and on the tidal flats. In August and September, they were observed frequently in groups of 10 to 15, either sitting on the ground or perched on low mangroves or dead snags sunning themselves. Coultas (field notes) received reports that they nested at a freshwater lake on the "main island" (Babelthuap?)

Ripley (1948) reports the occurrence of "about a dozen anhingas (presumably _Anhinga melanogaster_)" at Babelthuap on 12 November 1946.

=Fregata minor minor= (Gmelin)

Pacific Man-o'-War

_Pelecanus minor_ Gmelin, Syst. Nat., 1, pt. 2, 1789, p. 572. (No
type locality = Christmas Island, Indian Ocean.)

_Pelecanus aquila?_ Quoy and Gaimard, Voy. "Uranie," Zool., 1824,
p. 154 (Carolines).

_Pelecanus aquilus?_ Lesson, Man. d'Ornith., 2, 1828, p. 354
(Carolines).

_Atagen aquilus_ Gray, Cat. Birds Trop. Is. Pacific Ocean, 1859,
p. 61 (Ladrone or Marian Islands).

_Tachypetes aquila_ Finsch, Proc. Zool. Soc. London, 1880, p. 577
(Ruk); Hartert, Novit. Zool., 7, 1900, p. 11 (Ruk); Prowazek, Die
deutschen Marianen, 1913, p. 100 (Marianen).

_Tachypetes aquilus_ Finsch, Ibis, 1880, p. 333 (Taluit); _idem_,
Journ. f. Ornith., 1880, pp. 296, 310 (Ponapé, Kuschai); _idem_,
Ibis, 1881, pp. 109, 115 (Kuschai, Ponapé); Schmeltz and Krause,
Ethnogr. Abth. Mus. Godeffroy, 1881, pp. 299, 353 (Mortlock, Ruk).

_Fregata aquila_ Salvadori, Ornith. Papuasia, 3, 1882, p. 403
(Carolines, Marshalls); Wiglesworth, Abhandl. und Ber. Zool. Mus.
Dresden, no. 6, (1890-1891), p. 71 (Ruk, Luganor, Ponapé, Ualan,
Marshalls); Ogilvie-Grant, Cat. Birds British Mus., 26, 1898, p.
443 (Carolines, Marshalls); Finsch, Deut. Ver. zum Schultze der
Vogelwelt, 25, 1900, p. 452 (Ponapé, Kuschai, Marshalls); Seale,
Occ. Papers Bernice P. Bishop Mus., 1, 1901, p. 24 (Guam);
Safford, The Plant World, 7, 1904, p. 267 (Guam); Schnee, Zool.
Jahrbücher, 20, 1904, p. 390 (Marschall Inseln); Safford, Contr.
U. S. Nat. Herb., 9, 1905, p. 80 (Guam); Cox, Island of Guam,
1917, p. 22 (Guam).

_Fregata aquila palmerstoni_ Kuroda, in Momiyama, Birds
Micronesia, 1922, p. 35 (Carolines, Marshalls).

_Fregata minor peninsulae_ Mathews, Syst. Avium Australasianarum,
1, 1927, p. 233 (Carolines, Marshalls); Peters, Check-list Birds
World, 1, 1931, p. 96 (Carolines?, Marshalls?).

_Fregata minor palmerstoni_ Hand-list Japanese Birds, rev., 1932,
p. 186 (Yap, Faraulep, Truk, Lukunor, Ponapé, Kusaie, Namu,
Likieb); Bryan, Guam Rec., vol. 13, no. 2, 1936, p. 15 (Guam);
Yamashina, Tori, 10, 1940, p. 676 (Maug, Bikar).

_Fregata minor minor_ Hand-list Japanese Birds, 3d ed., 1942, p.
207 (Maug, Yap, Faraulep, Truk, Lukunor, Ponapé, Kusaie, Namu,
Bikar, Likieb).

_Fregata minor_ Borror, Auk, 64, 1947, p. 416 (Agrihan).

_Geographic range._--Eastern Indian Ocean to western Pacific Ocean.
Limits of range not certainly known. In Micronesia: Mariana
Islands--Agrigan, Maug, Saipan, Guam; Caroline Islands--Yap,
Faraulep, Truk, Lukunor, Ponapé, Kusaie; Marshall Islands--Namu,
Bikar, Likieb, Kwajalein, Bikini.

_Characters._--Adult male: Large sea bird with deeply forked tail;
blackish but wing-coverts paler; head and back glossy purple and
blue; breast lighter than belly. Adult female: Resembles adult
male, but head blacker; chin and throat grayer; breast more
whitish. Immature: Resembles adult, but head and throat whitish
washed with buff; breast dark brown; belly whitish.

_Measurements._--Two adult males measure: wing, 572; tail, 354,
396; exposed culmen, 98, 103; two adult females; wing, 583, 604;
tail, 365; exposed culmen, 119, 127. These four specimens are from
Bikini.

_Specimens examined._--Total number, 10 (3 males, 7 females), from
Marshall Islands, USNM--Bikini (March 11, 22, 29, 30, April 13, 29,
May 3, 14).

_Remarks._--The systematic position of the subspecies of _Fregata minor_ in the Pacific area is not well established. I am following the committee who prepared the Hand-list of Japanese Birds (Hachisuka _et al._, 1942:207) in using the name _F. m. minor_, although a thorough study may show that these birds have closer relationships to one of the other subspecies of the Pacific area.

_Fregata minor_ has been reported only occasionally in the Marianas and probably is not resident there. Borror (1947:416) reports the bird at Agrihan on August 11, 1945, and Seale (1901:24) mentions one taken at Guam in November, 1889. No records are known from the Palaus. In the Carolines the birds are probably resident, especially in the eastern part. In the Marshalls the species is a conspicuous member of the bird colonies on the coral atolls. Wallace (field notes) observed two birds at Loi Island in Kwajalein Atoll on May 7, 1944. Morrison obtained ten specimens at Bikini in the period from March through May in 1946.

=Fregata ariel ariel= (Gray)

Least Man-o'-War

_Atagen (sic) Ariel_ Gray, Gen. Birds, 3, 1845, col. pl. [185].
(Type locality, Raine Island, Queensland.)

_Pelecanus minor_ Lesson, Traite d'Ornith., 1831, p. 607
(Mariannes, Carolines).

_Tachypetes minor_ Hartlaub, Proc. Zool. Soc. London, 1867 (1868),
p. 831 (Mackenzie Group); Hartlaub and Finsch, Proc. Zool. Soc.
London, 1872, p. 90 (Uap); Gräffe, Journ. Mus. Godeffroy, 2, 1873,
p. 123 (Yap).

_Fregata minor_ Salvadori, Ornith. Papuasia, 3, 1882, p. 405
(Mariannes, Mackenzie); Wiglesworth, Abhandl. und Ber. Zool. Mus.
Dresden, no. 6, 1890-1891 (1891), p. 71 (Uap, Ngoli or Matelotas).

_Tachypetes aquila_ var. _minor_ Oustalet, Nouv. Arch. Mus. Hist.
Nat. Paris, (3), 8, 1896, p. 65 (Rota, Carolines, Marshalls);
Hartert, Novit. Zool., 5, 1898, p. 68 (Marianne).

_Fregata ariel_ Ogilvie-Grant, Cat. Birds British Mus., 26, 1898,
p. 447 (Marianas, Carolines); Seale, Occ. Papers Bernice P. Bishop
Mus., 1, 1901, p. 25 (Guam?); Safford, Osprey, 1902, p. 70
(Marianas); Bryan, Guam Rec., vol. 13, no. 2, 1936, p. 15 (Guam).

_Fregata ariel ariel_ Mathews, Birds Australia, 4, 1914-15, p. 285
(Carolines, Marshalls); Kuroda, in Momiyama, Birds Micronesia,
1922, p. 36 (Yap, Ngoli, Rota); Hand-list Japanese Birds, rev.,
1932, p. 186 (Rota, Yap, Ngulu, Uluthi); Hand-list Japanese Birds,
3d ed., 1942, p. 208 (Rota, Yap, Ngulu, Uluthi).

_Geographic range._--China coast and Philippines south to Australia
and east to Pacific islands. In Micronesia: Mariana Islands--Guam?,
Rota; Caroline Islands--Yap, Ngulu, Ulithi.

_Characters._--Adult male: Resembles _F. m. minor_, but smaller
and blacker with upper parts lustrous greenish-blue and white
patch on lower flank.

Adult female: Resembles adult male, but browner with paler nape
and white breast. Immature: Resembles adult, but with head, chin,
throat, and belly white washed with rufous.

_Remarks._--Like _F. minor_, the Least Man-o'-War has not been observed often in Micronesia. Marche obtained one female at Rota in June, 1888. D. H. Johnson saw a bird thought to be of this species at Agfayan Bay, Guam, on 4 June 1945. Records from the western Carolines are few. There are no reports of this bird from the Palaus and the Marshalls. It may breed on some of the atolls in the Carolines.

The two species of man-o'-war birds may be difficult to distinguish in the field. The smaller size of _Fregata ariel_ is perhaps the most useful character although it may be easily recognized also by the presence of the white flank patch, if it can be observed.

Both of the species of _Fregata_ discussed in this report have representatives in the Atlantic, Indian and Pacific oceans. Murphy (1936:920) has shown that the man-o'-war birds are able to cross the Isthmus of Panamá between the Pacific and Atlantic oceans. This route may also be the means of dispersal for other species. The irregular distribution of these birds as well as of other sea birds in the oceanic islands of the Pacific may be caused by their remaining over waters which contain preferred foods and their avoidance of waters which lack preferred foods.

=Butorides striatus amurensis= Schrenck

Amur Green Heron

_Ardea (Butorides) virescens_ var. _amurensis_ Schrenck, Reise Amur
Lande, 1, pt. 2, 1860, p. 441. (Type locality, Amurland.)

_Butorides striatus javanicus_ Hand-list Japanese Birds, rev.,
1932, p. 183 (Koror, Babelthuap).

_Butorides striatus amurensis_ Hand-list Japanese Birds, 3d ed.,
1942, p. 204 (Babelthuap, Koror); Mayr, Birds Southwest Pacific,
1945, p. 302 (Palau).

_Geographic range._--Breeds in northeastern Asia, China, Japan,
Bonins. Winters south to Philippines and Malaysia. In Micronesia:
Palau Islands--Babelthuap, Koror.

_Specimens examined._--Total number, 2 females, from Palau Islands,
AMNH--exact locality not given (Nov. 13, Dec. 17-18).

_Remarks._--The Amur Green Heron has been recorded as a winter visitor to the Palau Islands. Two females taken by Coultas in November and December, 1931, are immature. He comments (field notes) that he saw, in all, three birds in taro patch and mangrove swamp habitat.

=Bubulcus ibis coromandus= (Boddaert)

Cattle Egret

_Cancroma Coromanda_ Boddaert, Table Pl. enlum., 1783, p. 54. (Type
locality, Coromandel.)

_Ardeola ibis coromanda_ Hand-list Japanese Birds, rev., 1932, p.
183 (Koror).

_Bubulcus ibis coromandus_ Hand-list Japanese Birds, 3d ed., 1942,
p. 204 (Koror, Babelthuap); Mayr, Birds Southwest Pacific, 1945,
p. 302 (Palau).

_Geographic range._--India, Ceylon, east to China and Japan and
south to Malaysia. In Micronesia: Palau Islands--Babelthuap, Koror.

_Remarks._--The Japanese ornithologists have recorded the Cattle Egret from Babelthuap and Koror in the Palau Islands. It is a winter migrant.

=Egretta intermedia intermedia= (Wagler)

Plumed Egret

_Ardea intermedia_ Wagler, Isis, 1829, p. 659. (Type locality,
Java.)

_Egretta intermedia intermedia_ Hand-list Japanese Birds, rev.,
1932, p. 183 (Koror); Hand-list Japanese Birds, 3d ed., 1942, p.
203 (Koror); Mayr, Birds Southwest Pacific, 1945, p. 302 (Palau);
Baker, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p. 42 (Rota,
Guam, Peleliu, Angaur, Ulithi).

_Egretta intermedia_ Wharton and Hardcastle, Journ. Parasitology,
32, 1946, pp. 306, 310 (Ulithi); Baker, Ecol. Monogr., 16, 1946,
p. 408 (Guam).

_Geographic range._--India and Ceylon east to Malaysia,
Philippines, China and Japan. In Micronesia: Mariana
Islands--Saipan, Rota, Guam; Palau Islands--Koror, Peleliu, Angaur;
Caroline Islands--Ulithi.

_Characters._--Adult: A large white heron with green facial skin;
black legs, feet and toes. In breeding plumage: Head with crest;
neck and back with ornamental plumes; bill black. Winter plumage:
Without crest or plumes; bill yellow with blackish tip. Immature:
Resembles adult in winter plumage, but feathers soft and downy.

_Measurements._--Five males from Saipan, Rota, Guam, and Angaur
measure: wing, 295-321 (308); tail, 112-127 (119); culmen, 85-87
(87); tarsus, 111-118 (114); three females from Saipan, Ulithi,
Angaur: wing, 294-301 (297); tail, 101-116 (110); culmen, 77-83
(80); tarsus, 108-115 (107).

_Weights._--The author (1948:43) records the weights of two males
from Guam as 445 and 463.

_Specimens examined._--Total number, 8 (5 males, 3 females), as
follows: Mariana Islands, USNM--Saipan, 2 (Sept. 29, Oct. 2)--Rota,
1 (Oct. 31)--Guam, 2 (June 13); Palau Islands, USNM--Angaur, 2
(Sept. 21); Caroline Islands, USNM--Ulithi, 1 (Aug. 15).

_Food habits._--The NAMRU2 party found grasshoppers, other insects,
spiders and lizards in the stomachs of egrets taken at Guam,
Ulithi, and Angaur.

_Parasites._--Wharton and Hardcastle (1946:306, 310) obtained the
chiggers (Acarina), _Neoschöngastia egretta_ and _N. ewingi_, from
this egret from Ulithi.

_Remarks._--The NAMRU2 party obtained Plumed Egrets at Rota, Guam, Ulithi, and Angaur in 1945. Previously, the only known record was from Koror, as reported in the Hand-list of Japanese Birds (Hachisuka _et al._, 1932:183). In addition, in 1945, Joe T. Marshall, Jr., obtained two birds at Saipan, and Gleise (1945:220) reported seeing "white herons" at Tinian, which probably were egrets. Gleise estimated the number of these birds at Tinian to be fifty; he found them in swampy areas. At Rota, the NAMRU2 party found a flock of sixteen birds in a cultivated field on October 31. At Guam, egrets were first observed on February 25, 1945, when a flock of fourteen was found in a fallow rice paddy near Piti. This flock remained in this area and were seen occasionally until as late as June 13, when two were taken as specimens. A short time later (June 30) the entire area was cleared for military use and the birds were seen no more. At Agfayan Bay a flock of sixteen birds was found on the beach on July 24 and on August 6. These birds kept apart from Reef Herons which were also in the area. In June, 1946, M. Dale Arvey observed egrets in swamps along the Ylig River at Guam. At Ulithi Atoll, three egrets were seen on August 15 at Potangeras Island, feeding in grassy areas adjacent to the beach. In the southern Palaus, the NAMRU2 party found egrets in August and September on tidal flats and open grasslands at Peleliu and Angaur. At Peleliu, a flock of twenty-five birds was seen on September 8 and a flock of eight birds on September 16. At Angaur approximately twenty birds were seen in groups of five or more on September 21. These birds, unlike the Reef Herons, preferred grasslands to beach areas for feeding and were usually seen in sizeable flocks.

There was no evidence of breeding; specimens examined were either immatures or adults in winter plumage, since they had yellow bills tipped with black and slight or no development of ornamental plumes. Birds taken at Guam in June and at Angaur in September had no ornamental plumes, while birds taken at Ulithi in August, at Saipan in September and October, and at Rota in late October show some development of the back plumes. Wharton and Hardcastle (1946:306) found the same species of chigger on Plumed Egrets from Ulithi and from Okinawa in the Riu Kiu Islands. The NAMRU2 party observed the birds in Micronesia from February until October in 1945, and although the Plumed Egret may be considered as merely a visitor to Micronesia, it would not be surprising to find nests there. The fact that several new distributional records were obtained for Micronesia in 1945 may indicate that the birds have been overlooked by ornithologists in the past or that the birds are increasing the breadth of their winter (or breeding?) range.

=Demigretta sacra sacra= (Gmelin)

Reef Heron

_Ardea sacra_ Gmelin, Syst. Nat., 1, pt. 2, 1789, p. 640. (Type
locality, Tahiti.)

_Ardea jugularis_ Kittlitz, Observ. Zool., in Lutké, Voy. "Le
Séniavine," 3, 1836, pp. 286, 299, 304 (Ualan, Lougounor, Guahan);
Hartlaub, Journ. f. Ornith., 1854, p. 167 (Mariannen); Kittlitz,
Denkw. Reise russ. Amer. Micron. und Kamchat., 2, 1858, p. 63
(Ualan); Pelzeln, Reise "Novara," Vögel, 1865, pp. 118, 162, 120,
121 (Puynipet, Ualan).

_Ardea (Herodias) atra_ Gray, Cat. Birds Trop. Is. Pacific Ocean,
1859, p. 48 (Ladrone or Marian Islands, Caroline Islands).

_Ardea sacra_ Hartlaub, Proc. Zool. Soc. London, 1867 (1868), p.
831 (Matelotas Islands); Hartlaub and Finsch, Proc. Zool. Soc.
London, 1868, pp. 8, 118 (Pelews); Finsch and Hartlaub, Journ. f.
Ornith., 1870, p. 137 (Pelews, Matelotas); Gray, Hand-list Birds,
3, 1871, p. 28 (Marian, Carolines, Pelews, Matelotas); Hartlaub
and Finsch, Proc. Zool. Soc. London, 1872, pp. 89, 104 (Pelew,
Uap, Ualan); Gräffe, Journ. Mus. Godeffroy, 2, 1873, p. 123 (Yap);
Finsch, Journ. Mus. Godeffroy, 8, 1875, pp. 5, 32 (Palau); _idem_,
Journ. Mus. Godeffroy, 12, 1876, pp. 18, 38 (Ponapé, Ualan);
_idem_, Proc. Zool. Soc. London, 1877 (1878), p. 781 (Ponapé);
_idem_, Journ. f. Ornith., 1880, pp. 294, 306 (Ponapé, Kuschai);
_idem_, Ibis, 1880, pp. 220, 330, 332 (Taluit); _idem_, Proc.
Zool. Soc. London, 1880, p. 577 (Ruk); _idem_, Ibis, 1881, pp.
105, 106, 109, 115 (Kushai, Ponapé); Schmeltz and Krause, Ethnogr.
Abth. Mus. Godeffroy, 1881, pp. 299, 353 (Mortlocks, Ruk); Finsch,
Mitth. Ornith. Ver. Wien, 1884, p. 51 (Jaluit, Kuschai); Oustalet,
Le Nat., 1889, p. 261 (Mariannes); Wiglesworth, Ibis, 1893, p. 211
(Marshalls); Oustalet, Nouv. Arch. Mus. Hist. Nat. Paris, (3), 8,
1896, p. 36 (Guam, Marshalls, Palaos, Carolines); Schnee, Zool.
Jahrbücher, 20, 1904, p. 390 (Marschall-Inseln).

_Demiegretta sacra_ Salvadori, Ornith. Papuasia, 3, 1882, p. 348
(Marshalls, Ualan, Ponapé, Ruck, Pelew, Mariannis); Wiglesworth,
Abhandl. Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 67
(Marianne, Pelews, Luganor, Ruk, Ponapé, Ualan, Taluit); Hartert,
Novit. Zool., 5, 1898, p. 64 (Saipan); Sharpe, Cat. Birds British
Mus., 26, 1898, p. 137 (Pelew, Carolines, Marshalls); Hartert,
Novit. Zool., 7, 1900, p. 11 (Ruk); Seale, Occ. Papers Bernice P.
Bishop Mus., 1, 1901, p. 29 (Guam); Safford, Osprey, 1902, p. 67
(Marianas); _idem_, The Plant World, 7, 1904, p. 266 (Guam);
Kuroda, Avifauna Riu Kiu, 1925, p. 129 (Micronesia); Bryan, Guam,
Rec., vol. 13, no. 2, 1936, p. 15 (Guam); Bequaert, Occ. Papers
Bernice P. Bishop Mus., 16, 1941, p. 266 (Kusaie).

_Demigretta sacra_ Safford, Contr. U. S. Nat. Herb., 9, 1905, p.
79 (Guam); Prowazek, Die deutschen Marianen, 1913, p. 101 (Saipan,
Tinian); Cox, Island of Guam, 1917, p. 21 (Guam); Bequaert, Mushi,
12, 1939, p. 81 (Kusaie); Warton, Ecol. Monogr., 16, 1946, p. 175
(Guam); Warton and Hardcastle, Journ. Parasitology, 32, 1946, pp.
306, 316 (Ulithi, Guam).

_Demiegretta jugularis_ Takatsukasa and Kuroda, Tori, 1, 1915, p.
50 (Truk, Ponapé, Pelew).

_Demiegretta jugularis grayi_ Uchida, Annot. Zool. Japon., 9,
1918, pp. 484, 488, 490 (Ponapé).

_Demiegretta sacra sacra_ Kuroda, in Momiyama, Birds Micronesia,
1922, p. 36 (Guam, Saipan, Angaur, Luganor, Yap, Ngoli, Ruk,
Ponapé, Kusaie, Taluit).

_Demigretta sacra sacra_ Wetmore, in Townsend and Wetmore, Bull.
Mus. Comp. Zoöl., 63, 1919, p. 171 (Kusaie); Mathews, Syst. Avium
Australasianarum, 1, 1927, p. 198 (Carolines); Yamashina, Tori, 7,
1932, p. 406 (Ponapé); Hand-list Japanese Birds, rev., 1932, p.
183 (Saipan, Guam, Babelthuap, Peliliu, Angaur, Ngulu, Yap, Truk,
Lukunor, Ponapé, Kusaie, Jaluit, Majuro); Mayr and Amadon, Amer.
Mus. Novit., no. 1144, 1941, p. 10 (Guam, Saipan, Palau, Ponapé,
Kusaie, Ruk, Tah); Hand-list Japanese Birds, 3d ed., 1942, p. 203
(Saipan, Rota, Babelthuap, Peliliu, Angaur, Ngulu, Yap, Ulithi,
Truk, Lukunor, Ponapé, Kusaie, Jaluit, Arhno, Majuro, Moloclab,
Wotze, Likieb, Ailuk); Mayr, Birds Southwest Pacific, 1945, pp. 51,
284 (Micronesia); Downs, Trans. Kansas Acad. Sci., 49, 1946, p. 90
(Tinian); Strophlet, Auk, 63, 1946, p. 535 (Guam); Borror, Auk, 64,
1947, p. 417 (Agrihan); Stott, Auk, 64, 1947, p. 524 (Saipan);
Baker, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p. 42 (Rota,
Guam, Peleliu, Ulithi, Truk).

_Demigretta sacra micronesiae_ Momiyama, Tori, 5, no. 22, 1926, p.
110 (Type locality, Caroline Islands; Pelew, Yap, Truk, Ponapé,
Kusaie).

_Geographic range._--Coasts of Asia and adjacent islands from Korea
and Japan south to Malaysia, Australia, Melanesia, Polynesia and
Micronesia. In Micronesia: Mariana Islands--Agrigan, Tinian,
Saipan, Rota, Guam; Palau Islands--Babelthuap, Koror, Garakayo,
Ngesebus, Peleliu, Ngabad, Anguar; Caroline Islands--Ulithi, Yap,
Ngulu, Truk, Lukunor, Ponapé, Kusaie; Marshall Islands--Jaluit,
Arhno, Majuro, Maloclab, Wotze, Likieb, Ailuk, Bikini, Eniwetok,
Kwajalein.

_Characters._--A medium-sized heron with three color phases: in
gray phase color of body varies from "deep blackish-slate" to
light bluish-slate, particularly on the breast, with a white gular
stripe; wear and fading causes the color of the body to change to
brownish-slate; bluish-gray ornamental plumes may be present on
adult; in white phase color of body is pure white in adult stage;
plumage of immature may be mottled; in mottled phase there may be
a variable amount of gray and white (for complete study of
plumages of _Demigretta sacra_ see Mayr and Amadon, 1941:4).

_Measurements._--Mayr and Amadon (1941:1) record the length of the
wing of thirty adults from the Marianas and Carolines as 268-309
(284). Seven adult males obtained by the NAMRU2 party at Rota,
Guam and Peleliu measure: wing, 287-307 (294); tail, 95-114 (101);
culmen, 91-101 (96); tarsus, 78-87 (82); seven adult females, from
Rota and Guam: wing, 265-285 (275); tail, 87-96 (91); culmen,
86-92 (89); tarsus, 72-79 (76).

_Weights._--The author (1948:42) lists the following weights: four
adult males from Guam (gray phase) 590-667 (614); two adult males
from Guam (white phase) 600 and 662; five adult females from Guam
and Rota (gray phase) 477-553 (506).

_Specimens examined._--Total number, 80 (38 males, 40 females, 2
unsexed) as follows: Mariana Islands, USNM--Rota, 3 (Oct. 18, Nov.
2, 5)--Guam, 21 (May 11, June 6, 18, July 6, 8, 16, 24, 27, Aug. 6,
8, 27); AMNH--Saipan, 2 (July 22)--Guam, 9 (Feb. 11, Mar. 6, 7,
April 11, Aug. 15, Sept. 14, 16, Nov. 27, Dec. 20); Palau Islands,
USNM--Peleliu, 3 (Sept. 10, 16); AMNH--exact locality not given, 5
(Nov. 8, 21, 23); Caroline Islands, USNM--Ulithi, 1 (Aug.
15)--Kusaie, 1 (Feb. 8); AMNH--Truk, 3 (Feb. 18, May 20, Nov.
5)--Tah, 2 (Oct. 18)--Ponapé, 2 (Nov. 21, undated)--Kusaie, 26
(Jan. 25, 26, Feb., Mar. 10-20, 20-30, April 1-10, 18); Marshall
Islands, USNM--Bikini, 2 (March 29, April 2).

_Nesting._--The Reef Heron apparently nests on most of the islands
in Micronesia. The eggs are laid in a nest of grass and twigs on or
near the ground. Hartert (1898:64) records a nest found in grass at
Saipan on July 28, 1895. Yamashina (1932a:406) reports on one egg
taken at Ponapé on July 23, 1931. Marshall (1949:219, fig. 37)
found a breeding bird in April at Tinian. Coultas (field notes)
learned from the natives at Ponapé that the Reef Heron builds
a nest of small sticks near the ground in the mangrove thickets.
Two or three eggs are laid, and nests can be found at various times
of the year. Mayr and Amadon (1941:4) comment on the prolonged
breeding season and report six sets of eggs from Polynesia taken in
January, March, April, September, October, and November.

_Food habits._--The author (1948:42) found fish and crabs in the
stomachs of birds taken at Guam, Ulithi and Peleliu.

_Parasites._--Uchida (1918:484, 488, 490) found the following bird
lice (Mallophaga) on the Reef Heron at Ponapé: _Nirmus orarius_,
_Colpocephalum importunum_, and _Myrsidea teraokai_. Bequaert
(1939:81 and 1941:266) found the fly (Hippoboscidae),
_Ornithoctona plicata_, on the heron at Kusaie. Wharton (1946:175)
and Wharton and Hardcastle (1946:306, 316) obtained chiggers
(Acarina), _Neoschöngastia egretta_ and _N. carveri_, from the
Reef Heron at Guam and Ulithi.

_Remarks._--The species _Demigretta sacra_ contains two subspecies, the widespread _D. s. sacra_ and a larger form, _D. s. albolineata_ (Gray), known from New Caledonia and the Loyalty Islands. The latter subspecies is surrounded by the former, a distribution which closely parallels that in each of the species _Phalacrocorax melanoleucus_ and _Gygis alba_ of Oceania. Recently Delacour (in Delacour and Mayr, 1945b:105) has dropped the name _Demigretta_ placing all of the forms of this genus in _Egretta_. He says, "We cannot accept the genus _Demigretta_, which is based on the more extended feathering of the tibia, the different length and texture of the feathers of the trains, the shortness of the tarsus and the presence of a dark gray color phase. The latter exists in the Madagascan and African subspecies of _Egretta garzetta_."

The Reef Heron is a conspicuous member of the bird life of Micronesia, being recorded from most of the island groups. It prefers the placid and shallow waters of the lagoons and tidal beaches where it obtains the littoral animal life as food. The birds are seldom seen inland and usually frequent the beaches and rocky coasts. In this respect there is little opportunity for competition with the migratory Plumed Egret, which prefers the grassy upland and marsh areas and inland ponds. The Reef Heron is a quiet, usually solitary, and retiring bird, being exceedingly difficult to approach, especially when found on the open tidal flats.

The problem of plumages and color phases in the Reef Heron has been treated by Mayr and Amadon (1941:4-10). Specimens which they examined from Micronesia were found to be 54 percent gray, 40 percent white, and 6 percent mottled. Of the birds obtained by NAMRU2 field parties, fewer than 40 percent were white. Field counts showed a considerable variation in the ratio of grays to whites: Guam--6 grays to 4 whites; Ulithi--4 grays, 6 whites, 1 mottled; Palau--equal number of grays and whites; Truk--2 whites, 1 gray, 1 mottled. For some unknown reason, the gray birds were more easily approached than the white birds. Gleise and Genelly (1945:221) saw one white Reef Heron at Eniwetok. Wallace (field notes) found white herons more numerous than gray ones at Kwajalein in 1944 and 1945. Borror (1947:417) observed gray birds at Agrigan. Stott (1947:524) saw one blue heron on December 24, at Saipan. The 150 birds seen by him at Lake Susupe in December probably were Plumed Egrets.

In discussing the variation in the color phases of the Reef Heron throughout its range, Mayr (1924b:237) suggests that the reduced variability of small populations may not be due to accidental gene loss, but instead to the population having descended from a single pair or from one fertilized female. The descendents would naturally possess only those characters provided for in the genetic make-up of the parents. Reef Herons on New Zealand and in the Marquesas Islands all are gray, while at other island groups different proportions of gray and white individuals occur; such phenomena may result because of the genetic constitution of the "founders."

=Nycticorax nycticorax nycticorax= (Linnaeus)

Black-crowned Night Heron

_Ardes Nycticorax_ Linnaeus, Syst. Nat., ed. 10, 1, 1758, p. 142.
(Type locality, Southern Europe.)

_Nycticorax griseus_ Hartlaub and Finsch, Proc. Zool. Soc. London,
1872, pp. 89, 105 (Uap); Gräffe, Journ. Mus. Godeffroy, 2, 1873,
p. 123 (Yap); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden,
no. 6, 1890-1891 (1891), p. 69 (Uap).

_Nycticorax nycticorax_ Sharpe, Cat. Birds British Mus., 26, 1898,
p. 146 (Yap).

_Nycticorax nycticorax nycticorax_ Kuroda, in Momiyama, Birds
Micronesia, 1922, p. 36 (Mackenzie, Yap); Hand-list Japanese
Birds, rev., 1932, p. 183 (Yap, Uluthi); Hand-list Japanese Birds,
3d ed., 1942, p. 204 (Yap, Uluthi); Mayr, Birds Southwest Pacific,
1945, p. 302 (Marianas, Yap).

_Geographic range._--Europe and Africa east to Japan and Malaysia.
In Micronesia: Mariana Islands--Tinian; Palau Islands--Koror;
Caroline Islands--Yap, Ulithi, Truk.

_Specimens examined._--Total number, 2 immature females, as
follows: Palau Islands, USNM--Koror, 1 (Nov. 27); Caroline Islands,
AMNH--Truk, 1 (June 18).

_Remarks._--The Black-crowned Night Heron is a winter visitor to western Micronesia. Marshall (1949:221) records six of these birds on Tinian on April 4, 1945, and one on Koror on November 27.

=Nycticorax caledonicus pelewensis= Mathews

Rufous Night Heron

_Nycticorax caledonicus pelewensis_ Mathews, Bull. British Ornith.
Club, 46, 1926, p. 60. (Type locality, Pelew Islands.)

_Nycticorax caledonicus_ Hartlaub and Finsch, Proc. Zool. Soc.
London, 1868, pp. 117, 118 (Pelew); Sharpe, Cat. Birds British
Mus., 26, 1898, p. 158 (Pelew); Hartert, Novit. Zool., 7, 1900, p.
10 (Ruk); Reichenow, Die Vögel, 1, 1913, p. 255 (Palauinseln);
Takatsukasa and Kuroda, Tori, 1, 1915, p. 50 (Pelew); Uchida,
Annot. Zool. Japon., 9, 1918, p. 486 (Palau); Wetmore, in Towsend
and Wetmore, Bull. Mus. Comp. Zoöl., 63, 1919, p. 172 (Uala, Truk
Atoll); Kuroda, in Momiyama, Birds Micronesia, 1922, p. 37 (Pelew,
Ruk).

_Nycticorax manillensis_ Hartlaub and Finsch, Proc. Zool. Soc.
London, 1872, pp. 89, 105 (Pelew); Finsch, Journ. Mus. Godeffroy,
8, 1875, pp. 5, 33 (Palau); _idem_, Proc. Zool. Soc. London, 1880,
p. 577 (Ruk); Schmeltz and Krause, Ethnogr. Abth. Mus. Godeffroy,
1881, p. 353 (Ruk); Wiglesworth, Abhandl. und Ber. Zool. Mus.
Dresden, no. 6, 1890-1891 (1891), p. 69 (Pelew, Ruk).

_Nycticorax caledonicus pelewensis_ Mathews, Syst. Avium
Australasianarum, 1, 1927, p. 200 (Pelew, Carolines); Peters,
Proc. Boston Soc. Nat. Hist., 39, 1930, p. 271 (Pelew, Carolines);
Peters, Check-list Birds World, 1, 1931, p. 115 (Pelew); Hand-list
Japanese Birds, rev., 1932, p. 183 (Palau, Truk); Hand-list
Japanese Birds, 3d ed., 1942, p. 204 (Babelthuap, Koror, Coracel,
Truk); Amadon, Amer. Mus. Novit., no. 1175, 1942, p. 6 (Palau,
Ruk); Mayr, Birds Southwest Pacific, 1945, p. 285 (Palau, Truk);
Baker, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p. 43
(Angaur, Peleliu, Garakayo, Truk).

_Geographic range._--Micronesia: Palau Islands--Babelthuap, Koror,
Coracel, Garakayo, Peleliu, Ngabad, Angaur; Caroline Islands--Truk.

_Characters._--Adult: Size medium; head and nape dark slaty-black;
occipital plumes white with dark tips and shafts; back dark
reddish-brown, lighter on sides of neck, wings, wing coverts,
rump, and tail; under parts whitish with light reddish-brown on
sides of neck extending to throat and upper breast; tibia with
some brownish feathers; underwing pinkish; feet yellowish-brown;
bill black.

Immature: Resembles adult, but upper parts mottled black with
reddish-brown; underparts with lighter streaks of brown and
whitish on breast; feet yellowish; bill black above, yellowish
below.

Adult resembles _N. c. manillensis_ Vigors, but is duller above.

_Measurements._--Two adult males from Peleliu measure: wing, 293,
299; tail, 105, 107; culmen, 82, 89; tarsus, 79, 81; seven adult
females from Peleliu: wing, 269-286 (280); tail, 101-106 (104);
culmen, 76-84 (80); tarsus, 78-83 (80); one adult female from
Truk: wing, 280; tail, 97; culmen, 83; tarsus, 79.

_Specimens examined._--Total number, 27 (5 males, 18 females, 4
unsexed), as follows: Palau Islands, USNM--Peleliu, 9 (Aug. 31,
Sept. 1, 5, 6, 8, Dec. 6); AMNH--exact locality not given, 16 (Nov.
7, 8, 13, 23, 25, Dec. 1, undated); Caroline Islands, USNM--Truk, 1
(Feb. 16); AMNH--Truk, 1 (May 25).

_Nesting._--The NAMRU2 party observed a nesting colony of these
night herons at Peleliu on August 29, 1945. Approximately eight
nests were observed in a grove of saplinglike trees at the edge of
a mangrove swamp. These nests were 15 to 20 feet above the ground;
most of them contained one or two nestling birds. Two subadults and
three nestlings in postnatal molt were obtained; no eggs were
found. Marshall (1948:219) records breeding in August, September
and December.

_Food habits._--Baker (1948:43) reports that stomachs of night
herons obtained by the NAMRU2 party at Peleliu contained a great
variety of animal foods, including eels, fish, lizards (skinks),
crabs, shrimp, and insects. The stomach of one adult contained 14
large grasshoppers and four fish, totaling about 15 cc. in volume.
The nestlings had eels, skinks, and insects in their stomachs.

_Parasites._--Uchida (1918:486) found the bird louse (Mallophaga),
_Lipeurus baculus_, on the night heron at Palau.

_Remarks._--Amadon (1942:4-8) has made the most recent study of the species _Nycticorax caledonicus_ and recognizes eight subspecies from Australia and New Calendonia north to the Caroline and Bonin islands. This is one of the few tropical and subtropical species which has extended its range to the Bonin islands. The discontinuous distributions of this species prevents an accurate estimation of the route by which it reached the Bonins. The presence of the bird at Palau and at Truk makes it difficult to account for its absence at Yap and other intervening, and seemingly suitable, islands. Populations at Palau and Truk appear to be similar and are placed in the same subspecies, but when adequate material is available from Truk, further study may reveal that the populations on the two islands (Truk and Palau) are recognizably different.

At the southern Palau Islands, night herons were found by the NAMRU2 party in mangrove swamps, lagoons and on beaches. I found them to be inactive during the daytime; the birds were usually perched singly in trees or at the edge of the water. The birds appeared to have special roosting places and were observed sitting in the same place on several different occasions. McElroy of the NAMRU2 party reported seeing three night herons at Truk in December, 1945.

=Gorsachius goisagi= (Temminck)

Japanese Bittern

_Nycticorax goisagi_ Temminck, Pl. Col., livr. 98, 1835, pl. 582.
(Type locality, Japan.)

_Gorsakius goisagi_ Hand-list Japanese Birds, rev., 1932, p. 184
(Koror); Hand-list Japanese Birds, 3d ed., 1942, p. 204 (Koror);
Mayr, Birds Southwest Pacific, 1945, p. 302 (Palau).

_Geographic range._--Eastern China, Japan, Riu Kius, Formosa, and
Philippine Islands. In Micronesia: Palau Islands--Koror.

_Remarks._--_Gorsachius goisagi_ has been recorded from Koror in the Palau Islands. It may be classed as a rare migrant to western Micronesia.

=Gorsachius melanolophus melanolophus= (Raffles)

Malay Bittern

_Ardea melanolopha_ Raffles, Trans. Linn. Soc. London, 13, 1822, p.
326. (Type locality, Western Sumatra.)

_Nycticorax goisagi_ Hartlaub and Finsch, Proc. Zool. London,
1868, pp. 8, 118 (Pelew); _idem_, Proc. Zool. Soc. London, 1872,
p. 89 (Pelew); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden,
no. 6, 1890-1891 (1891), p. 68 (Pelew).

_Nycticorax melanolophus_ Finsch, Journ. Mus. Godeffroy, 8, 1875,
pp. 5, 35 (Palau).

_Gorsachius melanolophus_ Sharpe, Cat. Birds Brit. Mus., 26, 1898,
p. 166 (Pelew).

_Gorsahius melanolophus melanolophus_ Hand-list Japanese Birds,
rev., 1932, p. 184 (Pelew); Hand-list Japanese Birds, 3d ed.,
1942, p. 204 (Palau); Mayr, Birds Southwest Pacific, 1945, p. 302
(Palau).

_Gorsachius melanolophus melanolophus_ Mathews, Syst. Avium
Australasianarum, 1, 1927, p. 200 (Pelew).

_Geographic range._--India, Ceylon, southern China, Formosa,
Indochina, Malaysia. In Micronesia: Palau Islands--exact locality
unknown.

_Remarks._--Captain Tetens obtained a specimen of this bittern at the Palau Islands which was reported on by Hartlaub and Finsch (1868a:8, 1868b:118). It is probably a rare straggler to western Micronesia. The specimen has not been seen by me; it may be of the subspecies _G. m. kutteri_ (Cabanis), which is known from the Philippine Islands.

=Ixobrychus sinensis= (Gmelin)

Chinese Least Bittern

_Ardea Sinensis_ Gmelin, Syst. Nat., 1, pt. 2, 1789, p. 642. (Type
locality, China.)

_Ardea lepida_ Lesson, Traité d'Ornith., 1831, p. 573 (Marianne);
Hartlaub, Journ. f. Ornith., 1854, p. 167 (Mariannen).

_Ardea sinensis_ Kittlitz, Obser. Zool., in Lutké, Voy. "Le
Séniavine," 3, 1836, p. 305 (Guahan); Gray, Hand-list Birds, 3,
1871, p. 31 (Marian); Hartlaub and Finsch, Proc. Zool. Soc.
London, 1872, pp. 89, 105 (Uap); Gräffe, Journ. Mus. Godeffroy, 2,
1873, p. 123 (Yap); Finsch, Journ. Mus. Godeffroy, 8, 1875, pp. 5,
33 (Palau, Yap); _idem_, Proc. Zool. Soc. London, 1880, p. 577
(Ruk); Schmeltz and Krause, Ethnogr. Abth. Mus. Godeffroy, 1881,
p. 353 (Ruk).

_Ardea (Ardetta) sinensis_ Gray, Cat. Birds Trop. Is. Pacific
Ocean, 1859, p. 49 (Ladrone or Marian Islands).

_Ardetta Sinensis_ Salvadori, Ornith. Papuasia, 3, 1882, p. 364
(Pelew, Carolines, Mariannis); Oustalet, Le Nat., 1889, p. 261
(Mariannes); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden,
no. 6, 1890-1891 (1891), p. 68 (Marianne, Uap, Ruk, Pelew);
Oustalet, Nouv. Arch, Mus. Hist. Nat. Paris, (3), 8, 1896, pp. 38,
39 (Guam, Saypan, Ponapi, Ruk, Palaos); Hartert, Novit. Zool., 5,
1898, p. 65 (Guam); Sharpe, Cat. Birds British Mus., 26, 1898, p.
227 (Marianne, Carolines, Pelew); Hartert, Novit. Zool., 7, 1900,
p. 11 (Ruk); Safford, Contr. U. S. Nat. Herb., 9, 1905, p. 79
(Guam); Prowazek, Die deutschen Marianan, 1913, p. 100 (Saipan);
Cox, Island of Guam, 1917, p. 21 (Guam).

_Ardetta bryani_ Seale, Occ. Papers Bernice P. Bishop Mus., 1,
1901, p. 27 (Type locality, Guam); Safford, Osprey, 1902, p. 66
(Guam); _idem_, The Plant World, p. 266 (Guam).

_Ardetta sinensis sinensis_ Takatsukasa and Kuroda, Tori, 1, 1915,
p. 50 (Ruk, Pelew).

_Ixobrychus sinensis bryani_ Wetmore, in Townsend and Wetmore,
Bull. Mus. Comp. Zoöl., 63, 1919, pp. 173, 175 (Guam); Kuroda, in
Momoyama, Birds Micronesia, 1922, p. 37
(Guam,?Yap,?Mackenzie,?Pelew); _idem_, Avifauna Riu Kiu, 1925, p.
134 (Guam,?Yap,?Pelew); Mathews, Syst. Avium Australasianarum, 1,
1927, p. 202 (Guam,?Pelew); Peters, Check-list Birds World, 1,
1931, p. 121 (Guam); Hand-list Japanese Birds, rev., 1932, p. 184
(Saipan, Tinian, Rota, Guam); Oberholser, Bull. U. S. Nat. Mus.,
159, 1932, p. 18 (Guam); Bryan, Guam Rec., vol. 13, no. 2, 1936,
p. 15 (Guam); Hand-list Japanese Birds, 3d ed., 1942, p. 205
(Saipan, Tinian, Rota, Guam); Amadon, Bull. Bernice P. Bishop
Mus., 186, 1945, p. 25 (Guam); Stott, Auk, 64, 1947, p. 525
(Saipan); Baker, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p.
44 (Rota, Guam).

_Ixobrychus sinensis moorei_ Wetmore, in Townsend and Wetmore,
Bull. Mus. Comp. Zoöl., 63, 1919, p. 173 (Type locality, Uala,
Truk group); Kuroda, in Momiyama, Birds Micronesia, 1922, p. 38
(Ruk); Kuroda, Avifauna Riu Kiu, 1925, p. 134 (Ruk); Mathews,
Syst. Avium Australasianarum, 1, 1927, p. 202 (Middle Carolines);
Peters, Check-list Birds World, 1, 1931, p. 121 (Truk); Hand-list
Japanese Birds, rev., 1932, p. 184 (Palaus, Yap, Truk);
Oberholser, Bull. U. S. Nat. Mus., 159, 1932, p. 17 (Carolines,
?Pelews); Hand-list Japanese Birds, 3d ed., 1942, p. 205
(Babelthuap, Koror, Yap, Truk); Baker, Smithson. Misc. Coll., vol.
107, no. 15, 1948, p. 44 (Truk, Peleliu).

_Ixobrychus sinensis_ Hartert, Vogel pal. Fauna, 10, 1920, p. 1260
(Truk, Palau, Guam); Mayr, Birds Southwest Pacific, 1945, p. 285
(Marianas, Palau, Yap, Truk); Watson, The Raven, 17, 1946, p. 41
(Guam); Downs, Trans. Kansas Acad. Sci., 49, 1946, p. 91 (Tinian);
Wharton, Ecol. Monogr., 16, 1946, p. 174 (Guam); Delacour and Mayr,
Birds Philippines, 1946, p. 29 (Guam); Strophlet, Auk, 63, 1946, p.
536, (Guam); Baker, Condor, 49, 1947, p. 125 (Guam).

_Ixobrychus sinensis sinensis_ Hachisuka, Birds Philippines, 1,
1932, p. 365 (Guam, Truk); Robinson and Chasen, Birds Malay
Peninsula, 3, 1936, p. 195 (Marianne).

_Ixobrychus sinensis palewensis_ Momiyama, Bull. Biogeogr. Soc.
Japan, 2, 1932, p. 333 (Type locality, Pelew); Mathews, Ibis,
1933, p. 88 (Pelew).

_Ixobrychus sinensis yapensis_ Momiyama, Bull. Biogeogr. Soc.
Japan, 2, 1932, p. 333 (Type locality, Yap); Mathews, Ibis, 1933,
p. 89 (Yap).

_Geographic range._--Northeastern China and Japan south to
Micronesia, Malaysia, Burma, India and Ceylon. Winter visitor to
Papuan region. In Micronesia: Mariana Islands--Saipan, Tinian,
Rota, Guam; Palau Islands--Babelthuap, Koror, Peleliu; Caroline
Islands--Yap, Truk.

_Characters._--Adult male: A small bittern with crown and short
occipital crest slaty-black; mantle light buffy-brown; back and
rump gray; tail black; wing-coverts brownish-buff; primaries and
secondaries slaty-black; underparts yellowish buff; chin and
throat whitish; sides of head and neck and a line of feathers
across chest blackish edged with buff; bill yellowish green; feet
greenish yellow.

Adult female: Resembles adult male, but with upper parts mottled
brown and golden chestnut; underparts deep buff streaked with pale
brown on neck.

Immature: Resembles adult, with upper parts heavily streaked with
blackish-brown, and underparts streaked with chestnut and dark
brown.

_Measurements._--Measurements of specimens from Micronesia are
given in table 16.

TABLE 16. MEASUREMENTS OF _Ixobrychus sinensis_ FROM MICRONESIA

===========+=========+=====+=========+=======+========+========
| | | | | Full |
LOCATION | Sex | No. | Wing | Tail | culmen | Tarsus
-----------+---------+-----+---------+-------+--------+--------
Yap, Truk | males | 6 | 132 | 43 | 56 | 44
| | | 130-134 | 41-47 | 54-59 | 42-47
| | | | | |
Guam | males | 11 | 134 | 47 | 57 | 46
| | | 127-138 | 45-50 | 55-60 | 45-47
| | | | | |
Guam | females | 10 | 130 | 46 | 57 | 45
| | | 127-134 | 44-49 | 55-59 | 43-47
-----------+---------+-----+---------+-------+--------+--------

_Weights._--The author (1948: 44) records the weights of eight
adult males from Guam as 82-103 (92) and eight adult females from
Guam as 84-109 (95).

_Specimens examined._--Total number, 69 (34 males, 27 females, 8
unsexed), as follows: Mariana Islands, USNM--Saipan, 1 (Sept.
30)--Tinian, 1 (Oct. 13)--Guam, 29 (May 16, June 4, 6, 7, 8, 14,
18, 19, July 10, 16, 18, 24, 27, Aug. 4); AMNH--Saipan, 1 (Aug.
6)--Tinian, 3 (Sept. 13)--Guam, 14 (Feb. 1, Mar. 13, 29, July 11,
13, 25, Aug. 1, 7, 13, Sept. 4, 10, Dec. 8); Palau Islands,
AMNH--exact locality not given, 6 (Nov. 19, 21, 23, 25, Dec. 1,
18); Caroline Islands, USNM--Truk, 1 (Feb. 16); AMNH--Yap, 1 (not
dated)--Truk, 12 (Feb. 9, Mar. 5, 17, May 7, June 13, 14, 15, Oct.
3, Nov. 1, 5, Dec. 20).

_Nesting._--The author (1948:44) records a nest found by the NAMRU2
party near Achang Bay on Guam on June 6, 1945. It was found in a
cane thicket at the edge of a fallow rice paddy, approximately four
feet from the ground and was constructed of about three quarts of
reeds and cane. Two eggs found in the nest are oval, white with a
greenish cast and measure 33 by 24 and 34 by 24. On February 1,
1945, the writer found two recently occupied nests of the Chinese
Least Bittern at Oca Point, Guam. These nests were in dense
inkberry brush approximately five feet above the ground. The area
was not marshy, the nearest water being at the beach some 300 yards
away. Nearby one of the nests was found a young bittern, which
apparently had only recently left the nest. The pin feathers were
growing. A parent bird remained in the vicinity with the young bird
until it left the area after March 9.

_Food habits._--The Chinese Least Bittern feeds on animal foods
obtained along waterways, marshes and beaches as well as in
forests and fields. The NAMRU2 party observed several types of
insects in the stomachs of birds taken at Guam. Seale (1901:27)
found black crickets in stomachs of bitterns taken at Guam.
Coultas (field notes) learned from the natives of the Palau
Islands that the bittern feeds on land mollusks.

_Parasites._--Wharton (1946:174) obtained the chigger (Acarina),
_Trombicula acuscutellaris_, from the Chinese Least Bittern at
Guam.

_Remarks._--The Chinese Least Bittern has been regarded by many workers as consisting of several geographic races; as many as eight have been recognized. Other workers have concluded that _I. sinensis_ is made up of highly variable populations and that it lacks well-fined geographic variation. Hartert (1920:1260), Hachisuka (1932:365), and Mayr (1945a:285) have reached the latter conclusion. As yet this problem has not been satisfactorily solved; a thorough study is needed, but may not be possible until additional material, especially from the continental areas, can be obtained. In coloration there appears to be little difference between birds from the various localities in Micronesia. These birds may average slightly paler than populations from the continental areas, but on this basis I doubt that a person could recognize the Micronesian birds in a group of skins from many other localities. Birds in fresh plumage may show geographic differences better than slightly worn specimens. Measurements made by the author offer no clear-cut differences either.

_I. sinensis_ was first recorded in Micronesia by Quoy and Gaimard (1824:536), whose ship, the "Uranie," stopped at Guam. They called the bird "Petit Héron aux ailes noires." Most of the ornithological collectors in the years following Quoy and Gaimard obtained this bittern in Micronesia. At Guam, its abundance and the ease with which it may be approached and shot is attested by the large series obtained by collectors: Seale (1901:27) took eight birds; Marche (Oustalet, 1896:36) took eighteen skins; the NAMRU2 party took twenty-nine skins.

The Chinese Least Bittern is found in habitats associated with both salt water and fresh water, as well as in upland habitat in Micronesia. The bird appears to be well adapted to areas of open forest and coconut groves. Coultas (field notes) found the birds in taro patches in the Palaus. Although a considerable amount of field observing was done in the southern Palaus, the NAMRU2 party saw only one bird (September 13, 1945, at Peleliu). Perhaps the birds prefer Babelthuap and other large islands farther north in the chain. McElroy found bitterns in taro patches at Truk in December, 1945. The NAMRU2 party did not find any birds at Rota in October and November, 1945. Downs (1946:91) found the birds in upland sugar cane and beach habitats on Tinian.

Regarding the bittern in the Palaus, Coultas (field notes) writes, "Always found alone, never a pair. A bird that is not easily frightened. In the heat of the day, one finds it standing in the shade of a taro leaf quietly viewing the intruder and very reluctant about moving. I have tossed pieces of earth and sticks at the bird to encourage him to fly so that I would not blow him to pieces when I shot, but my efforts at dislodgement have been rewarded by harsh scolding squawks. It became necessary for me to move into proper gun range. I have also found them perched in low trees at the edge of taro swamps. In flight they are atrociously awkward. They can't keep a course and their legs dangle every-which way. Their jerky, slow flight usually ends abruptly when the bird becomes entangled in weeds or the branches of trees. Extracting himself from his predicament he is soon in another and invariably resorts to blasphemy."

=Ixobrychus eurhythmus= (Swinhoe)

Schrenck's Least Bittern

_Ardetta eurhythma_ Swinhoe, Ibis, 1873, p. 74, pl. 2. (Type
locality, Amoy Shanghai.)

_Ixobrychus eurythmus_ Mayr, Birds Southwest Pacific, 1945, p. 302
(Palau).

_Geographic range._--Southeastern Siberia and Japan south to India
and Malaysia. In Micronesia: Palau Islands--exact locality unknown.

_Specimens examined._--Total number, 3 (2 males, 1 female), from
Palau Islands, AMNH--exact locality not given (Nov. 19, 21, Dec.
3).

_Remarks._--Coultas obtained three immature specimens at Palau in November and December, 1931.

=Dupetor flavicollis flavicollis= (Latham)

Black Bittern

_Ardea flavicollis_ Latham, Ind. Ornith., 2, 1790, p. 701. (Type
locality, India.)

_Dupetor flavicollis_ Seale, Occ. Papers Bernice P. Bishop Mus.,
1, 1901, p. 26 (Guam); Bryan, Guam Rec., vol. 13, no. 2, 1936, p.
15 (Guam).

_Dupetor f. flavicollis_ Mayr, Birds Southwest Pacific, 1945, p.
302 (Guam).

_Geographic range._--Central China south to Malaysia and India. In
Micronesia: Mariana Islands--Guam.

_Remarks._--Seale (1901:26) records a female shot at the Agaña River on Guam on June 11, 1900. The skin probably is in the Bernice P. Bishop Museum in Honolulu.

=Anas oustaleti= Salvadori

Marianas Mallard

_Anas oustaleti_ Salvadori, Bull. British Ornith. Club, 4, 1894, p.
1. (Type locality, Mariannis Islands.)