The diet intake of Hazel Grouses Tetrastes bonasia adults was investigated in captivity in 1988 and from 1991 to 1993. Birds were fed on a mixture of commercial poultry rations and pet food with a supplement of fish meal from April to September. In addition, fibrous diets (Taraxacum officinale or Rumex obtusifolius from April to October and cabbage from November to March) were supplied. The mean (±SD) intake of diets in dry weight ranged from 17.0±2.2 to 20.9±2.7 g/bird/day for males and from 12.0±3.4 to 20.6±2.6 g/birds/day for females. The energy intake estimated based on diet intake and gross energy in diets ranged from 310.4±41.2 to 366.7±47.9 kJ/bird/day for males and from 220.7±63.3 to 379.2±48.6 kJ/bird/day for females. On the average, both diet and energy intake increased in winters and decreased in summers except for female in May and June. The increased energy intake of females in May might be related to the increased requirements for egg laying and decreased one in June was due to egg incubation. The mean body weight changed seasonally in both sexes, ranging from 344±7 g in May to 383±9 g in January for males and from 356±20 g in June to 412±31 g in May for females. The body weights of females were significantly larger than those of males in April and May. The diets used is nutritionally adequate in respect of seasonal changes in body weight which is similar to that in natural conditions. A standard diet for adults birds was presented based on the data for diet intake.

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Diets and foraging sites of the Grey Heron, Ardea cinerea, in the breeding season were investigated by means of collecting regurgitated food items under nests and direct observations at foraging sites at 18 heronries in all over Japan. The diets extended several taxonomical animal groups. However, a large proportion of fish, both marine and freshwater, and a small one of mammals and birds characterized Grey Herons in Japan, compared with European ones. Grey Herons substantially depended on artificial foraging environments such as rice fields and fish-farming preserves.

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Blossom-headed Parakeet Psittacula cyanocephala and Rose-ringed Parakeet P. krameri were recorded to cause 64.7% damage to a seed crop of African Marigold Tagetes erecta cv. Cracker Jack. This is the first ever report on the parakeet damage to marigold. The Blossom-headed Parakeet was the major depredator, whereas, the Rose-ringed Parakeet was occasional visitor to the crop. This was probably due to the difficulty the latter species faced in feeding on the tiny seeds of marigold with its larger beak and availability of more profitable alternative food for its consumptiori. The parakeets did not feed randomly, but preferred the flowers nearer to their perching site. Consequently, the damage caused at a particular point was negatively related to the distance from the perch. The damage was positively related to the distance from road. The side towards road suffered minimum damage (28.7%) which was significantly less than the damage inflicted on the other three sides (80.3%, 84.8% and 69.9%) this confirming the tendency of the parakeets to keep away from human disturtance. The results of this study may be helpful in planning more effective and less expensive strategies for reducing bird damage to a crop in a particular situation.

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Antipredator behavior of the Rufous Turtle Dove, Streptopelia orientalis was studied on the campus of University of Tsukuba from March, 1990 to November, 1991. The breeding doves showed alternative antipredator behavior against a human visitor: injury-feigning and threatening. Threatening behavior was sometimes followed by attack with wings. Injury-feigning and threatening behavior were observed in 20 and 29 of 124 nests observed. The frequency and intensity of the antipredator behavior were not related to nest site characteristics, environmental conditions, breeding season, and brood size, but frequency of threatening behavior increased after the 7th day of nestlings. Although fledging success was higher in threatening behavior nests after the 7th day, nest success and fledging success were not related to the type and frequency of antipredator behavior as a whole. It is suggested that the antipredator behavior of the dove is not effective against the main predators, crows, although the behavior may have played a role in avoiding ground or small predators in other habitat.

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A study on the habitat selection of Peking Robin Leiothrix lutea, recently having invaded into Japan, and the composition of the forest living bird communities was carried out at Mt. Hikosan, Kirishima, Mt. Sefuri, Mt. Kurodake and Mt. Ichifusa, from 1991 to 1992. The abundance of the Peking Robin was high at Mt. Hikosan, Kirishima and Mt. Ichifusa, but low at Mt. Sefuri and Mt. Kurodake. The Peking Robin preferred the forests of Tsuga and Abies and deciduous broadleaved forests with dense undergrowth mainly consisting of the bamboo. The Peking Robin foraged, mainly by gleaning, in the foliage in the lower layer of the forests. The segregations of habitat and of foraging microhabitat occurred between the Peking Robin and other species (Cettia diphone, Parus ater, P. montanus, P. major and P. varius) showing a similar altitudinal distribution. No remarkable influences on the native bird communities were detected. The Peking Robin may have invaded into a vacant niche, a lower layer in the deciduous broadleaved forests, in Kyushu.

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In order to determine factors which cause the variation of the ratio of cabbage leaves injured by Hypsipetes amaurotis, I counted the number of leaves injured and not injured for 10 cabbages sampled randomly from each ridge, and calculated the ratio of leaves injured. Analyses of linear regression showed that the ratio of cabbage leaves injured was higher near shelter belt.

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