Research was implemented on the Asian Stubtail (Urosphena squameiceps) that breed in lowl and forests of western Hokkaido. The juveniles were observed to moult into winter plumage about 20 days after fledging. The juvenile feathers, especially flight feathers, were shorter and weaker than those of adult feathers. The first winter plumage, however, was almost exactly the same as the adult plumage. This type of complete post-juvenile moult is usually seen in sedentary species, but the Asian Stubtail is a migrant that spends summers in Japan. One explanation for the complete post-juvenile moult is related to this species’ preferred summer habitat. The Asian Stubtail spends most of the summer months flitting about in dense undergrowth. The short juvenile feathers might be sufficient or even preferable for this sort of lifestyle. Later, however, longer, stronger flight feathers are required for the migration to the south.

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On 11 October 1994, one Lesser Whitethroat Sylvia curruca was captured during banding research at Nishikikyo, Hakodate-shi, Hokkaido. Measurements were wing 60.5mm, tail 54.5mm, tarsus 19.7mm, exposed culmen 8.9mm, total length 119.0mm and wing span 163.0mm. The bird showed a grey crown, with distinctly contrasting dark lores and ear-covers, white throat, white on outermost tail feathers and dark slate-colored legs. These characteristics are consistent with descriptions for this species by Svensson (1992) and Baker (1997). In addition, a skull ossification index of E, combined with frayed edges on the tail feathers, grayish-brown iris and distinct white markings on outermost tail feathers, suggested that the bird was an aduit. Sex and subspecies could not be positively identified, but given the geographical location and relative length of primary feather, S. c. blythi was considered likely. The Lesser Whitethroat breeds widely across the Eurasian continent, and winters from Africa to southern Asia. This was the first record for this species in Japan.

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Little Terns Sterna albifrons breed in Japan as far north as the Tohoku Region of Honshu. The tern's natural breeding habitat was coastal beaches and wide river gravels, but most of these habitats have been eliminated by landfill and river impoundment project. Newly reclaimed areas, especially in urbanized regions, have been serving as breeding grounds, but the number of little terns has decreased steadily, and the species is now listed as vulnerable species by the Japan Environment Agency (1991). Given the high value of land in coastal regions of Japan, restoring and setting aside of sufficient breeding habitats will be difficult. Artificial breeding habitats, including roof top habitats, are thus expected to play a major role in helping the Little Tern to recover in Japan.
This research, conducted from July 8-16, 1996, was designed to survey roof-top nesting sites provided for Least Tern Sterna antillarum and Black Skimmer Rynchops niger in the Florida Panhandle area. Research materials and on-site inspections were graciously facilitated by Jeffery Gore, and Heather Bolte, Florida Game and Fresh Water Fish Commission. The research focused on factors involved in successful use of rooftop breeding sites, such as substrate, protection from predations, etc.. The author now believes that buildings such as large warehouses found along the shores of Tokyo Bay could be covered with gravel and turned into artificial breeding habitat for Little Tern and several species of plover, which also now suffer from loss of natural breeding areas.

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