Leucalcyon albicilla owstoni Mathews, Syst. Avium Australasianarum, 1, 1927, p. 376 (Asuncion).
Halcyon chloris owstoni Takatsukasa and Yamashina, Dobutsu. Zasshi, 43, 1931, p. 484 (Asuncion); Hand-list Japanese Birds, rev., 1932, p. 180 (Asuncion); Hand-list Japanese Birds, 3d ed., 1942, p. 200 (Assongsong, Pagan, Almagan); Mayr, Birds Southwest Pacific, 1945, p. 293 (Almagan, Pagan, Agrigan, Asuncion); Peters, Checklist Birds World, 5, 1945, p. 209 (Asuncion, Pagan, Alamagan); Borror, Auk, 64, 1947, p. 417 (Agrigan).
Geographic range.—Micronesia: Mariana Islands—Asuncion, Agrigan, Pagan, Almagan.
Characters.—Adult: Resembles H. c. albicilla, but hind part of crown blue-green and black collar broader.
Immature: Resembles adult, but forehead buffy and edges of feathering on anterior crown, upper wing-coverts, and tips of secondaries brownish.
Measurements.—Measurements are listed in table 33.
Specimens examined.—Total number, 4 (2 males, 1 female, 1 unsexed), as follows: Mariana Islands, AMNH—Asuncion, 4 (Jan., July).
Remarks.—Marche obtained specimens of this bird at Pagan in November, 1887, and at Agrigan in December, 1888, and in February, 1889. Owston's Japanese collectors obtained birds at Asuncion in 1904, which were named as new by Rothschild. Apparently he used an immature specimen in preparing the diagnosis of his new subspecies. Borror (1947:417) visited Agrigan in 1945 and obtained specimens of this kingfisher. He reports that the bird is a "common and abundant species and probably nests on the island."
Evolutionary history of Halcyon chloris in Micronesia.—Halcyon chloris is distributed from eastern Africa at the Red Sea eastward through southern Asia to Malaysia, Australia and the Pacific islands. Peters (1945:207-213) recognized 47 subspecies within this species.
In its colonization of Micronesia, H. chloris apparently arrived first at the Palaus probably from the Philippines or the Moluccas. Whether H. cinnamomina was established at Palau prior to the arrival of H. chloris is unknown. H. chloris teraokai dominates most of the available habitats at Palau, although it has differentiated but little from subspecies to the west and southwest of Palau. Among named kinds it most closely resembles H. c. chloris (Boddaert) of the Moluccas, Lesser Sundas and adjacent areas in color and structure. The species did not succeed in establishing itself in the Carolines or at Guam, but did so in the Marianas at Rota and northward. In comparison with other subspecies of H. chloris those in the Marianas are characterized by a slight increase in size and a replacement of the bluish-green coloring of the head either partly or wholly by white. It is noteworthy that on the islands of Tinian and Saipan, which occupy a geographically intermediate position in the Mariana chain, the bird has an almost completely white head, whereas the birds on islands to the north and south have only partly white heads.
The geographic ranges of H. chloris and H. cinnamomina in Micronesia overlap only at Palau as shown by Mayr (1942b:181). Even here each is restricted to a different habitat. Possibly the present ranges resulted from competition between each group, and both may have had more extensive ranges in Micronesia in the past. Another possibility is that the original stock of H. chloris arrived in Micronesia via the Palaus and that of H. cinnamomina via Ponapé (eastern Carolinas), and that the resulting successful colonizations were a matter of chance. If this were the case the present day ranges may represent the total amount of dispersal that has taken place. The absence of kingfishers from Kusaie, Yap, Truk and other apparently suitable islands favors this possibility.
Eurystomus orientalis connectens Stresemann
Dollar Bird
Eurystomus orientalis connectens Stresemann, Novit. Zool., 20, 1913, p. 302. (Type locality, Moa.)
Eurystomus orientalis connectens Yamashina, Tori, 10, 1940, p. 675 (Babelthuap); Hand-list Japanese Birds, 3d ed., 1942, p. 199 (Babelthuap).
Eurystomus orientalis pacificus Mayr, Birds Southwest Pacific, 1945, p. 302 (Palau).
Geographic range.—Celebes and adjacent islands, Lesser Sunda Islands from Lombock to Damar, Southeastern Islands. In Micronesia: Palau Islands—Babelthuap.
Remarks.—Yamashina (1940:675) records an adult male taken at Babelthuap in 1938. He assigns it to E. o. connectens, comparing it with a series of 15 specimens of this race from Celebes, Halmahera and Batchian. Mayr (1045a:302) refers this visitor to Palau to E. o. pacificus (Latham); this form is migratory and may fly north from Australia to the Melanesian area between breeding seasons.
Hirundo rustica gutturalis Scopoli
Eastern Barn Swallow
Hirundo gutturalis Scopoli, Del. Flor. et Faune, Insubr., 2, 1786, p. 96. (Type locality, "in Nova Guinea," error = Panay, Philippine Islands.)
Hirundo rustica Gräffe, Journ. Mus. Godeffroy, 2, 1873, p. 112 (Yap); Schmeltz and Krause, Ethnogr. Abth. Mus. Godeffroy, 1881, p. 391 (Yap).
Hirundo rustica gutturalis Hand-list Japanese Birds, rev., 1932, p. 178 (Koror); Hand-list Japanese Birds, 3d ed., 1942, p. 198 (Koror); Mayr, Birds Southwest Pacific, 1945, p. 302 (Palau); Baker, Smithson. Mus. Coll., vol. 107, no. 15, 1948, p. 65 (Guam, Angaur, Ngesebus).
Geographic range.—Breeds in northeastern Asia, winters south to Australia and Pacific islands. In Micronesia: Mariana Islands—Guam, Tinian; Palau Islands—Babelthuap, Koror, Ngesebus, Peleliu, Angaur; Caroline Islands—Yap.
Specimens examined.—Total number, 13 (9 males, 3 females, 1 unsexed), as follows: Mariana Islands, USNM—Tinian, 10 (Oct. 23, 25); Palau Islands, USNM—Babelthuap, 1 (Nov. 27)—Angaur, 1 (Sept. 21); AMNH—exact locality not given, 1 (Oct. 26).
Remarks.—This swallow is a winter migrant to western Micronesia from Asia. In the Palau Islands in September, 1945, the NAMRU2 party saw the swallow at Ngesebus and Angaur in small flocks. At Guam, the NAMRU2 party saw one bird on October 7 and four birds flying near Agaña River on October 11. Strophlet (1946:535) saw one bird on October 28, 1945, and six birds on November 16 at Guam. Marshall (1949:221) found swallows at Tinian, Saipan and Palau from October to February. He found only immature birds.
Edolisoma tenuirostre monachum (Hartlaub and Finsch)
Cicada Bird
Campephaga monacha Hartlaub and Finsch, Proc. Zool. Soc. London, 1872, p. 99. (Type locality, Pelew Islands.)
Volvocivora monacha Finsch, Journ. Mus. Godeffroy, 8, 1875, pp. 4, 19, pl. 3, fig. 2-3 (Palau); idem, Journ. Mus. Godeffroy, 12, 1876, p. 28 (Palau); Schmeltz and Krause, Ethnogr. Abth. Mus. Godeffroy, 1881, p. 407 (Palau).
Lalage monacha Sharpe, Cat. Birds British Mus., 4, 1879, p. 105 (Pelew); Tristram, Cat. Birds, 1889, p. 186 (Pelew); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 25 (Pelew); Bolau, Mitteil. Naturhist. Mus. Hamburg, 1898, p. 53 (Palau); Matschie, Journ. f. Ornith., 1901, pp. 112, 113 (Palau); Dubois, Syn. Avium., 1, 1902, p. 303 (Pelew); Reichenow, Die Vögel, 2, 1914, p. 276 (Palau); Takatsukasa and Kuroda, Tori, 1, 1915, p. 54 (Pelew); Kuroda, in Momiyama, Birds Micronesia, 1922, p. 68 (Pelew); Hand-list Japanese Birds, rev., 1932, p. 175 (Palau); Hand-list Japanese Birds, 3d ed., 1942, p. 194 (Babelthuap, Koror).
Edolisoma monacha Mathews, Syst. Avium Australasianarum, 2, 1930, p. 541 (Pelew).
Edolisoma tenuirostre monacha Stresemann, Ornith. Monatsber., 47, 1939, p. 126 (Palau); Mayr, Birds Southwest Pacific, 1945, p. 294 (Palau); Baker, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p. 65 (Peleliu).
Geographic range.—Micronesia: Palau Islands—Babelthuap, Koror, Peleliu.
Characters.—Adult male: Forehead, crown, nape, back, and underparts near "Tyrian blue"; auriculars darker than back; lores and chin black; throat black washed with blue gray; wing feathers black, margined with pale blue; black tail tipped with whitish, and basal part of middle two rectrices colored like back; under wing dark except for whitish inner margins of secondaries; bill and feet black; iris dark brown.
Adult female: Resembles adult male, but forehead and under eye pale buff; superciliary stripe darker buff; crown, nape, and sides of neck dark slate-blue; mantle brown, feathers with buffy centers; back brown washed with burnt brown; feathers of rump and upper tail-coverts with terminal black bar edged with buff; wing and tail brownish-black, primaries margined with buff, innermost three secondaries and upper wing-coverts broadly edged with lighter buff, tail tipped with buff, more broadly so on outermost tail feathers, two outermost tail feathers with outer edge buff; two central tail feathers basally dark ochre; ear-coverts buff, tinged with black; chin, throat, and under wing-coverts deep buff; breast, abdomen, and flanks buff, feathers with subterminal blackish bar; under tail buff.
Immature: Resembles adult female, but crown, nape, and sides of neck brown; back faintly mottled with buff; tail feathers and primary wing-coverts tipped with white; younger birds may have upper parts margined with pale buff.
Measurements.—Measurements are listed in table 34.
Specimens examined.—Total number, 23 (13 males, 10 females), as follows: Palau Islands, USNM—Koror, 4 (Nov. 6, 14, 26, Dec. 5)—Peleliu, 2 (Aug. 29, 30); AMNH—exact locality not given, 17 (Oct., Nov., Dec.).
Subspecies No. Wing Tail Exposed
culmenTarsus E. t. monachum 10 98 80 21.0 23.0 96-103 76-83 20.0-22.5 22.5-24.0 E. t. insperatum 35 109 86 23.0 24.0 107-112 82-91 22.0-24.0 23.0-25.0 Molt.—Molt in this bird appears to take place in the period from August to December. Most of the specimens taken in August, October, November and December were in molt. None was taken in other months.
Food habits.—This bird feeds principally on insects. A female taken on August 29 had in its stomach about one and a half cc. of parts of grasshopper. Marshall (1949:212) records both animal and vegetable matter in the stomach of this bird.
Remarks.—The Cicada Bird at Palau inhabits the jungles, especially the marginal areas between the thick jungle and the more open woodlands. In 1945, the NAMRU2 party observed only two birds, both of which were obtained. These were found at Peleliu in a small area of undisturbed woodland at the edge of a mangrove swamp. Each bird was perched approximately 25 feet above the ground on the outer branches of a densely foliated tree. The bird is thought not to be so rare as our records indicate; probably its secretive habits conceal it from man except as he makes special search for it. Coultas (field notes) describes the bird as one of the true forest. He found it shy and retiring and possessing a very weak voice.
It may be noted that Delacour (1946:2) does not accept the genus Edolisoma but places birds which are currently assigned to it in the genus Coracina.
Edolisoma tenuirostre nesiotis (Hartlaub and Finsch)
Cicada Bird
Campephaga nesiotis Hartlaub and Finsch, Proc. Zool. Soc. London, 1872, p. 98. (Type locality, Uap.)
Campehaga nesiotis Gräffe, Journ. Mus. Godeffroy, 2, 1873, p. 123 (Yap); Schmeltz and Krause, Ethnogr. Abth. Mus. Godeffroy, 1881, p. 391 (Yap).
Volvocivora nesiotis Finsch, Journ. Mus. Godeffroy, 12, 1876, p. 28 (Yap).
Edoliisoma nesiotis Sharpe, Cat. Birds British Mus., 4, 1879, p. 56 (Yap); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 25 (Uap); Bolau, Mitteil. Naturhist. Mus. Hamburg, 1898, p. 53 (Yap); Matschie, Journ. f. Ornith., 1901, p. 112 (Yap); Dubois, Syn. Avium, 1, 1902, p. 299 (Uap); Reichenow, Die Vögel, 2, 1914, p. 274 (Karolinen = Yap); Kuroda, in Momiyama, Birds Micronesia, 1922, p. 68 (Mackenzie, Yap).
Edolisoma nesiotis Mathews, Syst. Avium Australasianarum, 2, 1930, p. 542 (Mackenzie group); Hand-list Japanese Birds, rev., 1932, p. 174 (Yap); Hand-list Japanese Birds, 3d ed., 1942, p. 194 (Yap).
Edolisoma tenuirostre nesiotis Stresemann, Ornith. Monatsber., 49, 1939, p. 126 (Yap); Mayr, Birds Southwest Pacific, 1945, p. 294 (Yap).
Geographic range.—Micronesia: Caroline Islands—Yap.
Characters.—Adult male: Resembles adult male of E. t. monachum. Adult female: Resembles adult female of E. t. monachum, but wings and upper parts less buffy and more rufous; eye-stripe rufous; breast barred on sides only.
Remarks.—No specimen of the Cicada Bird from Yap has been examined by me. For a long time this bird was thought to be a species distinct from any other member of this genus, but Stresemann (1939:126) arranged it as a subspecies of Edolisoma tenuirostre. The type specimen is an immature, and the adult is unknown. The presence of rufous coloring shows a relationship with E. t. insperatum of Ponapé, but Mayr, who has examined the type of E. t. nesiotis in the Hamburg Museum, and has obligingly showed me his notes on the bird, says that it has a greater resemblance to the Cicada Bird at Palau especially because of the amount of barring on the underparts. The true status of this bird, as well as that of other members of the avifauna of Yap, will be incompletely known until such time as good collections are available from this island group.
Edolisoma tenuirostre insperatum (Finsch)
Cicada Bird
Volvocivora inseperata Finsch, Proc. Zool. Soc. London, 1875, (1876), p. 644. (Type locality, Ponapé.)
Volvocivora insperata Finsch, Journ. Mus. Godeffroy, 12, 1876, pp. 17, 27 (Ponapé); idem, Proc. Zool. Soc. London, 1877 (1878), p. 779 (Ponapé); idem, Ibis, 1881, pp. 110, 112, 115 (Ponapé); Schmeltz and Krause, Ethnogr. Abth. Mus. Godeffroy, 1881, p. 281 (Ponapé).
Volvozivora insperata Finsch, Journ. f. Ornith., 1880, p. 289 (Ponapé).
Lalage insperata Sharpe, Cat. Birds British Mus., 4, 1879, p. 108 (Ponapé); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 25 (Ponapé); Bolau, Mitteil. Naturhist. Mus. Hamburg, 1898, p. 53 (Ponapé); Matschie, Journ. f. Ornith., 1901, pp. 112, 113 (Ponapé); Reichenow, Die Vögel, 2, 1914, p. 276 (Karolinen = Ponapé); Kuroda, in Momiyama, Birds Micronesia, 1922, p. 68 (Ponapé); Hand-list Japanese Birds, rev., 1932, p. 174 (Ponapé); Hand-list Japanese Birds, 3d ed., 1942, p. 194 (Ponapé).
Lisomada insperata Mathews, Novit. Zool., 24, 1928, p. 372 (new generic name); idem, Syst. Avium Australasianarum, 2, 1930, p. 545 (Ponapé).
Edolisoma tenuirostre insperata Stresemann, Ornith. Monatsber., 47, 1939, p. 126 (Ponapé); Mayr, Birds Southwest Pacific, 1945, p. 294 (Ponapé).
Edolisoma tenuirostre Mayr, Proc. 6th Pacific Sci. Congr., 4, 1941, p. 204 (Ponapé).
Geographic range.—Micronesia: Caroline Islands—Ponapé.
Characters.—Adult male: Resembles adult male of E. t. monachum, but larger; upper parts more grayish-blue; wings with outer edges bluish-gray and inner webbings grayish-white; central tail feathers with subterminal, roundish, black spots; two outermost tail feathers black tipped with broad, pale bluish-gray coloring; lores more bluish-gray and less black; ear-coverts pale bluish-gray; chin, throat, breast, abdomen, flanks, under wing, and under tail-coverts grayish-blue; bill and feet black; iris dark brown.
Adult female: Resembles adult female of E. t. monachum, but larger; forehead slate-gray; crown brownish-gray, browner on nape; back chocolate-brown; rump rufous; upper tail-coverts more cinnamon; wing and tail brownish-black, outer margins of primaries edged with buff; outer margins of secondaries and upper wing-coverts except primary wing-coverts edged with rufous; central tail feathers like back but tipped with buff, other tail feathers more broadly tipped with buff; lores grayish-black; malar stripe to auriculars darker and more brownish-black with lighter shafts; underparts rufous, under wing paler and more buffy.
Immature: Resembles adult female, but forehead grayish tinged with ochre; crown and neck brown becoming slightly more reddish on back and more burnt reddish-brown on rump; tail edged and tipped with buff; primaries tipped with whitish, secondaries broadly edged with buff, primary wing-coverts tipped with buffy-white; lores blackish; ear-coverts rufous with lighter shafts; tail feathers pointed while in adult more rounded. Younger birds resemble older ones, but plumage except wings and tail may be spotted or barred with buff and black with whitish margins.
Measurements.—Measurements are listed in table 34.
Specimens examined.—Total number, 46 (23 males, 23 females), from Caroline Islands, AMNH—Ponapé (Nov., Dec.).
Nesting.—Coultas (field notes) writes that the nest is cup-shaped, made of grasses and strands of hair fern, and placed at low elevations in small trees and bushes. He was told that two eggs are laid. He comments that the nesting season had just been completed in November and December (the time of his visit to Ponapé), because he noted juveniles being attended and fed by the adults.
Molt.—Most of the specimens taken by Coultas in November and December are in fresh plumage or in the final stages of molt, indicating that the molt was initiated possibly in September and would be completed possibly in January. This time of molt appears to be approximately one month later than the time of molt of E. t. monachum of Palau. Probably the bird at the Palau Islands breeds slightly earlier in the year than the subspecies on Ponapé.
Examination of the large series of birds taken by Coultas at Ponapé shows the presence of three types of plumages. The writer has not made a thorough diagnosis of these plumages, but suspects that the phenomenon obtained here is the same as was found by Mayr (1933e) in his study of Neolalage banksiana (Gray), which is a related bird. Immatures of E. t. insperatum seemingly present two plumages, which, if Mayr's arrangement is followed, may be interpreted as a more primitive or "retarded" type in one case, with less striking plumage, barred with black and buff, and a more advanced or "progressive" type in the other case, with plumage of the latter resembling more the adult type, especially the adult female. It was not ascertained whether any of these specimens represented adult birds in "retarded" plumage.
Remarks.—The Cicada Bird at Ponapé resembles in habits its related subspecies at Palau. Coultas (field notes) writes that it is a forest bird, with retiring habits. He observed the birds in small groups, and describes their musical call notes as "to-to-wee, to-to-wee" repeated several times.
Evolutionary history of Edolisoma tenuirostre in Micronesia.—Mayr (in Stresemann, 1939:126) first pointed out the close relationship between the cicada birds of Micronesia and Edolisoma tenuirostre of the Solomon Islands. Up to that time the Micronesian birds were considered to belong to the genus Lalage. The cicada birds probably invaded Micronesia along two independent routes from a dispersal center in the Papuan area. The form at Palau, E. t. monachum, resembles closely several of the subspecies to the south and southwest, particularly those in the New Guinea area. Aside from the smaller size of the Palau form there are differences in coloration between this bird and those of Melanesia. In the adult female and the juvenile there are differences in the amount of barring on the underparts and in the shade of color on the upper parts. In the adult male there are differences in the marginal coloring of the primaries and secondaries. E. t. nesiotis may have arrived at Yap from Palau. Little is known concerning the taxonomic position of this bird. On the basis of the information available, it appears closer to the Palau bird than the Ponapé bird in color; however, in size it probably more closely approaches the latter subspecies.
The Ponapé Cicada Bird, E. t. insperatum, appears to represent a colonization distinct from that which established the populations at Yap and Palau. This conclusion is based on the fact that the adult female of E. t. insperatum has distinctive reddish coloring and lacks the barring on the underparts, and that it may have been derived from an ancestral stock, which was reddish and not barred, such as E. t. remotum of the New Ireland area. The three subspecies in Micronesia may represent remnants of a single colonization, since additional material from Yap may prove that this island population has characters intermediate between those of the other subspecies of Micronesia.
Dicrurus macrocercus harterti S. Baker
Black Drongo
Dicrurus ater harterti S. Baker, Novit. Zool., 26, 1918, p. 299. (Type locality, Formosa.)
Dicrurus macrocercus Baker, Trans. 11th N. Amer. Wildlife Conf., 1946, p. 211 (Rota).
Dicrurus macrocercus harterti Baker, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p. 65 (Rota).
Geographic range.—Formosa. In Micronesia: Mariana Islands—Rota (introduced).
Specimens examined.—Total number, 7 (4 males, 3 females), from Mariana Islands, USNM—Rota (Oct. 18, 19, Nov. 2).
Remarks.—This drongo was introduced from Formosa to Rota by the Japanese South Seas Development Company (Nanyo Kohatsu Kabushiki Kaisha) apparently in 1935. An illustrated booklet, printed by this organization and seen by members of the NAMRU2 party at the Rota Civil Government headquarters, showed pictures of the captive birds before release and indicated that they had been brought to Rota for the purpose of controlling destructive insects. Dr. Charles Vaurie has examined these birds and compared them with a series of drongos from Formosa in the collection of the American Museum of Natural History.
The drongo appears well adapted at Rota, where it prefers cultivated areas and the bombed village sites to thick woodlands. Birds were found in small flocks often perched in large shade trees in village areas. Weights of two immature males are 53 and 61 grams. One adult male measures: wing, 144, tail, 153, culmen, 26, tarsus, 22.
Corvus kubaryi Reichenow
Marianas Crow
Corvus Kubaryi Reichenow, Journ. f. Ornith., 1885, p. 110. (Type locality, Palau, error = Guam.)
Corvus solitarius Kittlitz, Obser. Zool., in Lutké, Voy. "Le Séniavine," 3, 1836, p. 305 (Guahan); Bonaparte, Comptes Rendus Acad. Sci. Paris, 37, 1853, p. 830 (Mariannes); Kittlitz, Denkw. Reise russ. Amer. Micron. und Kamchat., 2, 1858, p. 143 (Guahan); Oustalet, Nouv. Arch. Mus. Hist. Nat. Paris, (3), 7, 1895, p. 216 (Guam and Rota).
Corvus spec. Hartlaub, Journ. f. Ornith., 1854, p. 167 (Mariannen); Gray, Hand-list Birds, 2, 1870, p. 12 (Marianne).
Corvus kubaryi Hartert, Novit. Zool., 5, 1898, p. 59 (Guam, Rota); Wheeler, Report Island of Guam, 1900, p. 13 (Guam); Matschie, Journ. f. Ornith., 1901, p. 112 (Guam); Seale, Occ. Papers Bernice P. Bishop Mus., 1901, p. 55 (Guam); Safford, Osprey, 1902, p. 69 (Guam); idem, The Plant World, 7, 1904, pp. 3, 264 (Guam); idem, Contr. U. S. Nat. Herb., 9, 1905, p. 79 (Guam); Prowazek, Die deutschen Marianen, 1913, pp. 87, 102 (Marianen); Reichenow, Die Vögel, 2, 1914, p. 306 (Palau); Takatsukasa and Kuroda, Tori, 1, 1915, p. 64 (Marianne); Cox, Island of Guam, 1917, p. 21 (Guam); Kuroda, in Momiyama, Birds Micronesia, 1922, p. 69 (Guam, Rota); Meinertzhagen, Novit. Zool., 33, 1926, p. 73 (Guam); Hand-list Japanese Birds, rev., 1932, p. 169 (Guam, Rota); Bryan, Guam Rec., vol. 13, no. 2, 1936, p. 25 (Guam); Hand-list Japanese Birds, 3d ed., 1942, p. 187 (Guam, Rota); Mayr, Birds Southwest Pacific, 1945, p. 298 (Guam, Rota); Watson, The Raven, 17, 1946, p. 41 (Guam); Wharton, Ecol. Monogr., 16, 1946, p. 174 (Guam); Strophlet, Auk, 1946, p. 540 (Guam); Baker, Ecol. Monogr., 16, 1946, p. 408 (Guam); idem, Condor, 49, 1947, p. 125 (Guam); idem, Smithson. Misc. Coll., vol. 107, no. 15, 1948, p. 66 (Guam, Rota).
Corone phillipina Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 46 (Marianne).
Corone kubaryi Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 46 (Pelew, error = Guam).
Geographic range.—Micronesia: Mariana Islands—Guam, Rota.
Characters.—Adult: A small, black crow with a slight greenish-black gloss on head; back, wings, and tail with bluish-black gloss; underparts with dull, greenish-black gloss; bases of feathers light grayish, more nearly white on neck, producing a somewhat ragged appearance; nasal bristles short but extending over nostrils and base of culmen; bill and feet black; iris dark brown. Female smaller.
Immature: Resembles adult, but feathers with less gloss; wings and tail browner.
Measurements.—Measurements of Corvus kubaryi are listed in table 35.
Weights.—The NAMRU2 party obtained weights of the Marianas Crow as follows: from Guam, 5 males, 231-270 (256), 11 females, 205-260 (242); from Rota, 1 male, 256; 1 female, 260 grams.
Location Number
and
sexWing Tail Full
culmenTarsus Guam 9 males
236 (229-244)
165 (158-170)
55 (51-57)
51 (49-52)
19 females
227 (222-241)
151 (143-166)
50 (47-54)
50 (46-54)
Rota 3 males
235 (233-236)
167 (166-169)
54 (53-56)
50 (49-51)
Specimens examined.—Total number, 49 (20 males, 27 females, 2 unsexed), as follows: Mariana Islands, USNM—Guam, 26 (May 25, 29, June 4, 7, 8, 9, 18, 28, 29, July 10, 12, 18, Sept. 5, 11)—Rota, 4 (Oct. 22, 25, 29); AMNH—Guam, 19 (Jan., Feb., March, Aug., Sept., Dec.).
Nesting.—In the spring of 1945, the NAMRU2 party obtained records of nesting activities by crows. One nest was observed on March 8 in a banyan tree. Specimens collected from May to September were not in breeding condition, and it is thought that the nesting period is concentrated in the winter and spring months. Watson (1946:41) reports finding a young crow being fed on May 8 by an adult.
Molt.—The Marianas Crow molts in the period from May to August or September. Most of the birds taken by the NAMRU2 party in this period were in the process of molt. Skins obtained at Rota in late October also exhibit signs of molt. Specimens taken in December, January and February are in fresh or slightly worn plumage. The crow presents an exceedingly shabby appearance in molt, because the grayish and whitish basal parts of the feathers are exposed.
Food habits.—The crow is an omnivorous feeder. Stomachs examined contained both plant and animal food. Both Seale (1901:55) and Safford (1905:79) comment on the damage which the crow does to the corn crop at Guam. Seale remarks that the crow has a reputation for plundering nests of other birds. The NAMRU2 party saw crows being chased by starlings on several occasions.
Parasites.—Wharton (1946:174) obtained the chigger (Acarina), Trombicula sp., from the crow at Guam.
Remarks.—The Marianas Crow is confined to the forested areas and to the coconut plantations at Guam. The birds were seen as singles or in small flocks, often along the roadways. In a count of the number of birds seen along the roadways of Guam, the author (1947:124) found crows to constitute 2.4 per cent of the total population of birds counted and observed the crow on 21.6 per cent of the 125 roadway counts made. Coultas (field notes) noted the birds at the northern part of Guam. The NAMRU2 party found the birds distributed in most parts of the island but usually they were infrequent near areas where large numbers of service personnel were stationed. The birds were often noisy when flying in small flocks or in pairs; Seale (1901:55) also notes this. When observed in jungle areas, the birds were generally quiet, feeding and perching in dense foliage. At Rota, the NAMRU2 party found the bird to be fairly numerous and with habits resembling those of the crow at Guam. No differences in color or structure could be found between the specimens of crows obtained at the two islands.
Kittlitz (1836:305) was the first person to write an account of the crow at Guam. He called it Corvus solitarius and remarked that he later found the same species in the Philippines. Wiglesworth (1891a:46) also considered the crow at Guam to resemble one found in the Philippines and called it Corone phillipina. Later Reichenow named the bird Corvus kubaryi with the type locality as the Palau Islands. This locality proved to be erroneous and the bird was judged to be from Guam by Hartert (1898:59), who did not use the name C. solitarius because it was a nomen nudum, and recognized C. kubaryi as the correct name.
Evolutionary history of Corvus kubaryi.—Meinertzhagen (1926:59) writes that "Environmental influences seem to be mainly, if not entirely, responsible for geographic differences in the genus Corvus." Such may be the case in C. kubaryi, which is a small, dull-colored crow with a relatively unmodified bill. In structure, it has little resemblance to other crows found in the Pacific area. Kittlitz was the first to note a resemblance between the bird at Guam and one in the Philippines. Oustalet (1896:70) wrote that the bird at Guam is related to crows of the Moluccas and New Guinea. Although not closely related to the Hawaiian Crow, C. tropicus, both have little gloss on their feathers, a character which is common to many of the insular populations of crows. Mayr (1943:46) is of the opinion that the Hawaiian bird was derived from a North American ancestor, although Bryan (1941:187) suggests that it is related to C. macrorhynchus of southeastern Asia and remarks that the Hawaiian Crow, "has some relation to the Guam Crow." In looking for the ancestral stock of C. kubaryi, the several species of crows which occur to the north, west and south of the Marianas have been examined. In size and general structure, C. kubaryi appears to be closest to the C. enca group, and not as closely related to the C. macrorhynchus group. The small size, the shape of the culmen, the lack of pointed feathers on the breast, and the presence of white on the basal parts of the feathers of the nape are characters which C. kubaryi has in common with C. enca. Nasal bristles cover the frontal base of the culmen in C. kubaryi; this character is found also in C. enca florensis. C. kubaryi differs from the C. enca group by lacking the purple sheen on the upper parts; this sheen is conspicuous in the latter species. C. kubaryi appears to have little in common with C. meeki of the Solomons and C. orru of the Moluccas and New Guinea area. There is apparently no close relation between the Marianas Crow and the crow which reaches the Bonins. The latter crow, according to the Hand-list of Japanese Birds (Hachisuka et al., 1932:1), is called C. coronoides hondoensis Momiyama and is apparently now extinct in the Bonins.
In summary, it may be said that C. kubaryi is an isolated and modified species of crow, which probably has been living at Guam and Rota for a considerable length of time. Whether it once lived on other islands in Micronesia is unknown, but it is entirely possible that the present population may represent a remnant of one which formerly had a more extensive distribution. The characters which show its distinctness from possible ancestral species include its small size, its slender bill, and its dull coloration. It is thought to have been derived from the C. enca group, C. e. pusillus of the Philippines or C. e. celebensis of the Celebean area.
Luscinia calliope calliope (Pallas)
Siberian Rubythroat
Motacilla Calliope Pallas, Reise durch versch. Prov. russ. Reichs, 3, 1776, pp. 261, 325, 697. (Type locality, Yenesei.)
Luscinia calliope calliope Hand-list Japanese Birds, rev., 1932, p. 178 (Koror); Hand-list Japanese Birds, 3d ed., 1942, p. 197 (Koror); Mayr, Birds Southwest Pacific, 1945, p. 302 (Palau).
Geographic range.—Breeds in northeastern Asia. Winters south to Malaysia. In Micronesia: Palau Islands—Koror.
Remarks.—The Siberian Rubythroat is considered to be a casual winter visitor to the Palau Islands.
Monticola solitaria philippensis (Müller)
Chinese Blue Rock Thrush
Turdus philippensis Müller, Natursystem Supplements- und Register-Band, 1776, p. 145. (Type locality, Philippine Islands, ex Buffon.)
Monticola philippensis philippensis Hand-list Japanese Birds, rev., 1932, p. 177 (Koror); Mayr, Birds Southwest Pacific, 1945, p. 302 (Palau).
Monticola solitarius philippensis Hand-list Japanese Birds, 3d ed., 1942, p. 197 (Koror).
Geographic range.—Breeds in northeastern Asia and Japan. Winters south to Malaysia. In Micronesia: Palau Islands—Koror.
Remarks.—The Chinese Blue Rock Thrush is apparently an infrequent winter visitor to the Palau Islands.
Turdus obscurus obscurus Gmelin
Dusky Thrush
Turdus obscuras Gmelin, Syst. Nat., 1, 1789, p. 816. (Type locality, Lake Baikal.)
Turdus obscuras Hartlaub and Finsch, Proc. Zool. Soc. London, 1872, pp. 89, 96 (Pelew); Finsch, Journ. Mus. Godeffroy, 8, 1875, pp. 5, 22 (Palau); Kuroda, in Momiyama, Birds Micronesia, 1922, p. 66 (Pelew).