[in Japanese]

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Color-ring banding of Great Cormorants Phalacrocoax carbo in Japan began in 1975. The first and second reports on this research were issued respectively in 1983 and 2000. This report summarizes the results for 2000 to 2007.
Banding was implemented primarily during the breeding season, from March through May, at sixteen colonies. Most of these were on the Pacific Ocean side of Honshu Island, but several were on the Japan Sea side. A total of 4,882 cormorants were banded between March 3, 2001 and December 14, 2007. Of these, the overwhelming majority (4,824) were chicks that had not yet fledged. In the past, only fragmentary data was obtained from visual confirmations and recaptures of banded cormorants, especially with regard to long-range movements. With the population of cormorants expanding, however, an understanding of their movement patterns has become even more essential. During this most recent period, the number of birds banded, as well as the number of colonies targeted, more than tripled compared to that of the previous period.
In the future, cormorant colonies in which the nests are low enough to allow access to banding research must beprotected. In addition, there is a need for technological improvements in the color bands themselves.

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A juvenile male Japanese robin (Erithacus akahige tanensis) was captured and banded on November 6, 2006. The bird was caught in a mist net along a small stream in a narrow valley, at the base of Mt. Oyama in Kanagawa Prefecture, a little bit to the west of Tokyo, and was released after being measured and banded. The identification as subspecies tenansi rather than subspecies akahige was based on a lighter-colored bill, and lack of a dark grey band on the chest. In addition, the bird was identified as a juvenile male by sharp tips on the tail feathers, and lack of a clear boundary between the orange and gray colors on the chest. This was the first record in Kanagawa Prefecture for subspecies tanensi. Normally, this subspecies is thought to reside primarily on offshore islands such as Kozu, Miyake and Hachijo Islands in the Izu Island group; while subspecies akahige inhabits the mainland. Subspecies tenensi, however, frequents dwarf bamboo thickets and other dense vegetation, and rarely ventures out into open areas. This makes observation, especially during the autumn migration period when the birds do not sing. This record indicates the possibility that some subspecies tanensi may be mixed in with the spring and late summer migrations of subspecies akahige.

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A juvenile Black Bittern (Ixobrychus flavicollis) was captured and banded on November 7, 2006. The bird was caught in a mist net along a small stream in a narrow valley, at the base of Mt. Oyama in Kanagawa Prefecture, a little bit to the west of Tokyo, and was released after being measured and banded. Buff edges on both the wing coverts and back feathers identified the bird as a juvenile, but sex could not be determined. This species is widely distributed from southern Asia across Southeast Asia to Papua New Guinea and Australia. Observations in Japan date to 1970, but the first officially confirmed record was obtained from an island off Niigata Prefecture, along the Japan Sea side of Honshu Island, in 1981. In recent years confirmed observations have been made in the Izu Islands, but only one record had been obtained for the Honshu mainland. Of the four subspecies of the Black Bittern, subspecies flavicollis is found in China and Southeast Asia, and has been shown to migrate. Subspecies australis, on the other, inhabits Australia, and is not believed to migrate widely. Considering this distribution and migratory behavior, the captured bird is thought to most likely belong to subspecies flavicollis. The natural environment in which the bird was captured, consisting of dense shrub with stream and ponds nearby, was similar to that described as favorable to this subspecies. On the other hand, on the day of the capture a high wind had been blowing, and there is thus a strong possibility that the bird may have been blown in from the nearby Izu Islands.

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