Artamus leucorhynchus pelewensis Finsch
White-breasted Wood-swallow
Artamus pelewensis Finsch, Journ. Mus. Godeffroy, 12, 1876, p. 41. (Type locality, Palau.)
Artamus leucorhynchus Hartlaub and Finsch, Proc. Zool. Soc. London, 1868, pp. 116, 118 (Pelew); idem, Proc. Zool. Soc. London, 1872, pp. 89, 99 (Pelew); Finsch, Journ. Mus. Godeffroy, 8, 1875, pp. 4, 18 (Palau); Walden, Ibis, 1876, p. 188 (Pelew).
Artamus pelewensis Finsch, Proc. Zool. Soc. London, 1877 (1878), p. 739 (Pelew); Tweeddale, Ibis, 1878, p. 385 (Pelew); Sharpe, Cat. Birds British Mus., 13, 1890, p. 9 (Pelew); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 26 (Pelew); Bolau, Mitteil. Naturhist. Mus. Hamburg, 1898, p. 62 (Palau); Matschie, Journ. f. Ornith., 1901, p. 112 (Palau); Dubois, Syn. Avium, 1, 1902, p. 533 (Pelew); Reichenow, Die Vögel, 2, 1914, p. 346 (Pelew).
Artamus leucorhynchus pelewensis Stresemann, Novit. Zool., 20, 1913, p. 293 (Palau); Hand-list Japanese Birds, 3d ed., 1942, p. 193 (Babelthuap, Koror); Mayr, Birds Southwest Pacific, 1945, p. 297 (Palau).
Artamus melanoleucus pelewensis Kuroda, in Momiyama, Birds Micronesia, 1922, p. 69 (Pelew); Mathews, Syst. Avium Australasianarum, 2, 1930, p. 635 (Pelew); Hand-list Japanese Birds, rev., 1932, p. 174 (Palau).
Geographic range.—Micronesia: Palau Islands—Babelthuap, Angaur.
Characters.—Adult: Upper surface black, except for back which is slightly brownish and for rump which is white; underparts white, except for chin, throat and upper breast which are black; wings with grayish tips; bend of wing black; bill milky blue, nostril and tip black; feet black; iris dark brown.
Immature: Resembles adult, but black feathers with brownish tinges; primaries tipped with white.
Measurements.—Measurements are listed in [table 44].
Table 44. Measurements of Artamus leucorhynchus pelewensis Finsch
Table 44. Measurements of Artamus leucorhynchus pelewensis Finsch
| Number and Sex | Wing | Tail | Culmen | Tarsus |
| 5 males | 134 | 68 | 25 | 16.5 |
| (132-136)) | (66-69) | (24-26) | ||
| 4 females | 134 | 68 | 24 | 16.5 |
| (132-136) | (67-69) | (16.5-17.0) |
Specimens examined.—Total number, 12 (7 males, 5 females), from Palau Islands, AMNH—exact locality not given (March, Nov., Dec.).
Remarks.—Little is known concerning the habits and distribution of the white-breasted Wood-Swallow at Palau. Coultas obtained a series of eight birds in 1931; he writes (field notes) that his native hunter took every bird that he saw. The natives told him that they did not know the nest of the bird. Coultas concluded that the bird was not common. He commented that it may be found perched in the top of a tree on a dead branch or "even displaying in the air." The NAMRU2 party found no evidence of this bird in the southern Palaus in 1945. The specimens obtained by Coultas in November and December, 1931, were in molt and had small gonads.
This wood-swallow is the only Micronesian representative of Artamus leucorhynchus. Like several other species of birds it has become established only at the Palau Islands, and has either been unsuccessful in colonizing other parts of Micronesia or has not had the opportunity to do so. This bird had been compared with specimens representing ten subspecies of A. leucorhynchus in Melanesia and Malaysia. A. l. pelewensis differs from these subspecies examined by its blacker appearance, with only a faint brownish wash on the back, and by its shorter, first primary. The curvature of the upper mandible of the bird in the Palaus is similar to that of P. l. leucorhynchus of the Philippines; the mandible is less curved than that of P. l. celebensis of Celebes; the mandible is slightly thicker than that of P. l. leucopygialis of the New Guinea and Australian region. In length of wing P. l. pelewensis resembles closely P. l. leucorhynchus; P. l. celebensis has a longer wing and P. l. leucopygialis has a shorter one. Stresemann (1913:293) points to a close relationship between P. l. pelewensis and P. l. musschenbreeki of Tenimber and Babber islands and P. l. melaleucus of New Caledonia; Mayr (1945a:284) says the bird in the Palaus came from the Papuan area. Probably P. l. pelewensis has reached the Palau Islands from the New Guinea area by way of the Philippines.