The nesting ecology of a marked population of the Fan-tailed Warbler Cisticola juncidis was investigated for five years, 1978-1982, in the Shinoda-yama grassland in Japan.
(1) Males constructed their first nests almost synchronously one month after their arrival.Nest building activity occurred throughout the day and continued until the end of August.
(2) Almost all the males re-used some materials from abandoned nests; seemingly due to a shortage of cobwebs.
(3) Nests were supported by living grasses, mainly a kind of pampas grass (41.9%), alang grass (34.0%), and eulalia (11.3%).
(4) Nests were on average about 20 cm above the ground, and the height gradually in-creased as the season went on.
(5) Nest entrances faced mainly to the east due to westerly winds in the area.
(6) The activity patterns and the characteristics of courtship nests mostly agreed with those of two other local populations in Japan

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(1) A census of the breeding population of the Rock Ptarmigan Lagopus mutus was made in the Southern Japan Alps in mid June 1981. The area investigated includes Mt. Kitadake(3, 192m), Mt. Aino (3, 189m) and Mt. Nõtori (3, 025m).
(2) A total of 87 males and 16 females were observed. Based on these observations, territorial marks (use of favourite look-out stations, etc.), vegetation and topograghy, we estimated that about 100 territories exist in our study area.
(3) Many territories were observed on mountains with peaks above 3, 000m. The density of territories was highest with 14.1 territories/km² (35.2 birds/km²) on Mt. Kitadake. The average density in the study area was 6.95 territories (17.4 birds/km²).
(4) The density of territories was highest between 2, 900 and 3, 000m (12.2 territories/km²) and decreased towards both lower and higher elevations.
(5) The density of territories was found to be closely correlated with the distribution of the creeping pine (Pinus pumila) of less than 40 cm bight.(6) The habitat of the Rock Ptarmigan in Japan is discussed.

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Seasonal variations in the daily activity patterns of Latham's snipe Gallinago hardwickii were studied along the lower reaches of the Tokachi River, eastern Hokkaido, from late April to late August 1984. During the study birds were counted along a 3km transect at a speed of 3km per hour and an intensive search was made for sitting snipe in a 1.4km² area of riverbed. During the breeding season aerial displays were the . most conspicious behaviour, followed by calling from poles or trees. The number of snipes counted increased at 03:00, 06:00-07:00 and 19:00 in late April and mid-May, and also at 17:00 in late May and mid-June, showing 3 or 4 peaks. Peaks occurred just before and after sunrise or sunset. The maximum number of snipes counted in the daytime, between 06:00 and 07:00, increased from late April to May, then decreased gradually until the end of June. There-after the number of snipes observed declined abruptly because of the decrease in detectability and in numbers. Although censuses can be carried out from late April to late June, foran effective census it is desirable to survey snipes between 06:00 and 07:00 in May.

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Bird communities were studied in relation to vegetation in a natural deciduous broad-leaved wood and a young larch plantation in Obihiro (42°39′N, 143°01′E), Hokkaido from late April to early May 1983 and from late April to mild-June 1984. The deciduous study area (6.5ha) is a mixture of Phellodendron amurense, Sophora japonica and other deciduous broad-leaved trees with a dense undergrowth of shrubs and Sasa paniculata, tree density being 1, 145/ha. The young larch plantation (6.0ha) consists of Larix leptolepis of about 7 m high with a dense undergrowth of Sasa paniculata, tree density being 2, 800/ha. A total of 25 species of birds was recorded throughout the present study, of which 21 were observed in the deciduous wood and 12 in the larch plantation. Eighteen species had stationary home ranges in the study area; 15 species and 14.8 pairs in the deciduous wood, and 7 species and 11 pairs in the larch plantation. Emberiza spodocephala was the most dominant species both in the deciduous wood and larch plantation, whereas Parus palustris and Cettia squameiceps were common in the deciduous wood. Emberiza cioides and Cettia diphone, on the other hand, were common in the larch plantation. In the deciduous wood birds feeding and nesting on trees and shrubs were abundant but in the larch planatation birds feeding andnesting on shrubs and the ground dominated. The species diversity index (H') was 3.300 in the deciduous wood and 2.084 in the larch planatation. The similarity index betweenthe birds community of both plots was 0.42.

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A Female Redhead Ayrhya americana was observed and photographed at Shinobazu Pond, Tokyo, on 16 January 1985, as it fed among lotus in company with Common Pochards Aythya ferina. This is the first record of this species from Japan.

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Siskins Carduelis spinus are winter visitors to Japan, but it is presumed that summer records refer to a small breeding population in Hokkaido and in northern Honshu, although until now breeding has not been proven in Honshu. On May 6, 1985 I found a nest with two nestlings just before fledging on a ceder tree in Shimokita Peninsula, Aomori Pref., in northernmost Honshu. The nest, made of cedar bark and 7cm in outer diameter, was on a twig covered with foliage, 4.5m above the ground. The nestlings were fed 5 times between 11:10 and 18:00 by the female alone. These nestlings made trial flight, called, moved around in the nest, and then crouched. After they had left the nest, I inspected it and found that the bottom of the nest was clean, but around the edge of the nest some white droppings were left.

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