1977年10月20日から1978年4月9日まで,北海道大学苫小牧地方演習林で,ヤマゲラが寝くらに残したふんを採集し分析した.ヤマゲラが利用した寝ぐらは森林観測塔に設置されていた巣箱である.
(1)同定できた餌品目は,動物では昆虫網,くもがた類,整形類,植物では樹木の種子であった.
(2)ふん分析の結果を苫小牧演習林における季節区分に従って区分した.トビイロケアリはどの季節区分にも数多く出現した.しかし,厳冬IIには急に減少し,晩冬に再び増加した.
(3)樹木の種子は秋に特に多かったが,初冬,厳冬Iまで多く出現した.しかし,厳冬II以降は急に減少し,再び増加することはなかった.
(4)アリ以外の動物餌は,秋,初冬は少なかったが,厳冬Iにはヒメバチが多数出現した.厳冬IIに数,頻度共に多く出現したのはクモだけであった.
(5)ふん分析の問題点について言及し,またヤマゲラの採餌生態,ふんに出現する食物(特にアリ類),環境要因との関係について論議した.

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The records of the Pallas's Reed Bunting Emberiza pallasi from Japan were reviewed. This species was apparently rare in our country and only three specimens were collected in the pre-war time. In the past few years, however, eleven birds were captured and banded by the Bird Banding Center teams (Table 1). There were also few sight records, though none of them seemed to be authentic. According to these records, the species is probably an uncommon, but regular, winter visitor to Japan. It has been found to inhabit in coastal reed beds along rivers from October to March (sometimes to May).
Although this species has been subdivided into two or three subspecies, most examples from Japan are referable to Emberiza pallasi polaris MIDDENDORFF which have more northern distributional range than the other subspecies.
Two kinds of call notes, i.e. a short 'jitt' and a long sharp 'chii', were heard during our banding work. The former resembled one of call notes uttered by the Japanese Reed Bunting Emberiza yessoensis yessoensis and the latter resembled to the uttered call of the Swinhoe's Reed Bunting E. schoeniclus pyrrhulina.
According to our field observations, females and immatures of E. pallasi were difficult to distin-guish from those of E. schoeniclus, although males may be identifiable at short distance.
The iris of E. pallasi is chestnut in adult and olive-brown in juveniles, as is the case in E. s. pyrruhulina. Consequently the iris colour, as well as the shape of the tail-feathers and the skull ossifica-tion, is a useful character for ageing in the winter season.

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Check-list of Japanese Birds (1974) follows VAURIE (1955, 1959) in synonymizing Turdus chrysolaus orii YAMASHINA with nominate chrysolaus. Re-examination of materials, including the type and other specimens from the Kurile Islands, has shown that the breeding males of orii, the northern Kurile population (Paramushir, Araido, Matsuwa), can be separated readily from those of nominate chrysolaus from Sakhalin, Hokkaido and Honshu, on account of the very dark coloration of their head. In this subspecies (breeding males) the head and crown is blackish sooty brown in contrast to the olive-brown nape and back, giving an appearance of being black-capped, whereas in nominate chrysolaus the upper parts are more or less uniform olive brown. The wing length and the bill height (but not bill length) of orii are also larger, although the ranges of variation overlap to some extent between the two forms (Figs. 1-2). It therefore seems to me best to retain orii as a distinct subspecies. In females, juveniles and first winter males orii is rather similar to the nominate form, but in males the characteristics of orii may become recognizable in February or March as the wear of the plumage progresses.

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