[in Japanese]

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Molt data for Barn Swallow (Hirundo rustica) were collected during banding research conducted in five areas of Japan; Okinawa, Kagoshima, Fukuoka, Aichi and Tokyo. Swallows were banded from late August to early September in Kagoshima, from mid to late September in Okinawa, in early August in Tokyo and Aichi, and during mid July in Fukuoka. All captured swallows were banded with metal rings, and molt status was recorded for most of the birds. Analysis of the data shows that molting commenced in mid July. By early August 61% of banded birds were in molt. The percentage of molting individuals was 88% from late August to early September; and 83% from mid to late September. Over 99% of the banded juvenile birds were not in molt. Some of these second year birds may not have completely molted into adult plumage.
Some suspended molt was observed, at a ratio of 0% in mid July and 7.1% in early August for Tokyo, 44.6% from late August to early September in Kagoshima, and 70.4% from mid to late September in Okinawa. The ratios of suspended molt observed in this research are higher than those reported for Europe. This may be due to differences in migration routes. In Europe most of the migration occurs over land, with only a short 15 km stretch of ocean across the Straits of Gibraltar. In Asia, however, banding research indicates that swallows migrate from breeding grounds in Japan along the Ryukyu Islands to wintering areas in island and mainland Southeast Asia. The suspended molt observed in Japan may help the swallows avoid a loss in flight efficiency required for the long migration over open water.

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Molting data was obtained on 20 August 2008 for an injured Little Cuckoo Cuculus poliocephalus that was treated, banded and released; and on 22 August for a female Oriental Cuckoo C. saturatus that was found deceased. The data were obtained in Oita Prefecture, in the eastern part of the island of Kyushu, southwestern Japan. Both these species are summer breeders in Japan, with respectively 42 and 147 banding records from 1961 to 1995. Data on aging and molting, however, are few in number. The reddish color of the rescued Little Cuckoo indicates that this individual was most likely a female, and the lack of juvenile feathers indicates that the bird was an adult that had passed at least one winter. The tartials and body feathers were in the process of molting, and the tail contained both new and old feathers, all of which showed worn edges. The iris was dark brown. The deceased Oriental Cuckoo was too badly decomposed to determine sex, but the lack of juvenile feathers indicate that this bird was also past its first winter. The 2^nd, 3^rd and 7^th primaries were fresh, but the remaining primaries were worn and faded. All the secondaries except for the 7^th and 8^th, as well as all the tartials, were also old feathers. The greater, median and lesser covers, as well as the alula, showed a mixture of new and old feathers. The two central tail feathers were in the process of growing (score 4 on the Ginn and Melville ranking), but the remaining tail feathers were old. The body feathers were not yet molting.

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