(1) In the course of a study of the social behavior of Azure-winged Magpies Cyanopica cyana in 1984 and 1985 at Azumino, Nagano Prefecture, we found heavy brood parasitism by Common Cuckoos.
(2) A total of 31 nests out of 41 (75.6%), among core groups and 15 nests of 30 (50.0%) in secondary groups were parasitized. Eight nests contained two, and one contained three cuckoo eggs.
(3) The earliest magpie nests, in which the first egg was laid during the middle of May, were parasitized less frequently (11.1%) than later nests (68.8%).
(4) Cuckoo eggs (23.4×17.4 mm, n=13) were smaller than Azure-winged Magpie eggs (27.67×20.16 mm, n=16).
(5) Azure-winged Magpies suffered heavy brood parasitism by Common Cuckoos probably because of the short history of the host-parasite relationship between them, which is as a result of a recent expansion of their breeding areas in Nagano Prefecture.

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Mass-mortalities of short-tailed shearwaters (Puffinus tenuirostris) occurred in 1983-1985, along the Pacific coast of central and northern Honshu, Japan, from late May to mid June. The carcass numbers were annually counted along three 20 km courses at three localities on the Pacific coasts; Atsumi Peninsula in Aichi Prefecture, Kujukuri Beach in Chiba Prefecture and Ogawara Coast in Aomori Prefecture. At Kujukuri Beach, annual carcasses were 32.5, 44.0 and 26.8/km from 1983 to 1985; these were two to four times as many as in the previous years, 12.3±5.7/km (1977-1982). Similarly, high values of 16.4 and 47.6/km were recorded at Atumi in the first two years, with lower number in 1985. At Ogawara Coast few carcasses were found in the first two years, but increased in 1985. This northward shift of mortality was likewise indicated by answers to our questionnaire issued to wildlife divisions of Pacific coast prefectures from Okinawa to Hokkaido. Of 2, 258 carcasses collected, more than 99% were considered to be young of the year with a mean weight of 286.4±22.3 (SD) gr. (n=59), about 110 g lighter than that of the live birds, 399.4±32.7 (SD) gr. (n=22), captured in fishing nets. The main cause of mass-mortality of young birds was due to emaciation. Since the mass-mortality of this species has been recorded in 1964 and 1973-1975 in Japan and in 1934, 1942 and 1954 in Australia, a rough ten-year periodicity could be expected, and the recent one of 1983-1985, reported here, supports this theory.

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Studies were made on breeding biology of the Hazel Grouse Tetrastes bonasia vicinitas in captivity and in Tokachi and Kushiro districts, eastern Hokkaido, between 1983 and 1984.
(1) In wild state nests were found in coniferous forests, mixed forests of coniferous and broadleaved trees, mature larch plantations, fir plantations and bamboo grass lands.
(2) The nesting period ranged from early May to late June and hatching days were concent-rated in the 10 days from 15 to 26 June in 1984.
(3) The clutch size varied between 4 and 9 eggs with an average of 7. Only the female incubated the eggs.
(4) In artificial breeding mating behaviors such as display, chasing female, singing and copulation were observed. Nests were built within a day. During a period of 21 days, a total of 14 eggs were laid when 2 or 3 eggs were left in the nest each day.
(5) Fifty eight eggs collected from nests in fields, and 9 eggs obtained from the birds kept in captivity were incubated artificially. The hatchability in artificial incubation was 93% by using the incubator and 71.4% by using "chabo", a domestic fowl.
(6) Chicks obtained from 72 eggs were reared in captivity in 1983 and 1984. They reared up to 5 weeks of age in chick-rearing cages at 25°C. Rations of 13 to 19% crude protein were fed to them. Chick group-activities of walking and eating, and resting occurred alternately.
(7) The juveniles, from 6 to 15 weeks of age, were transferred in sunny rearing cages. They were reared in groups of 5 to 8 birds. A ration of 13 to 15% crude protein was fed to them. They exhibited such behvaior as preening and sand-bathing. Cannibalism also occurred often in this age.
(8) The adults, from 16 weeks of age, were reared in groups of 2 or 3 birds. A ration of 10% crude protein was fed to them from October to February. From March to June, the crude protein was increased to a level between 15 and 20%. Adults at 16 weeks of age showed clear distinction betwwwn sexes, and exhibited mating behavior such as display and singing.

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(1) Between 1874 to 1985, 115 Oriental Ibises Threskiornis melanocephalus were recorded in 77 occasions in Japan. The number of records is increasing in recent years, probably due to the increase of bird watchers.
(2) Of the 77 records, 84.4% were single individuals, while the largest flock was composed of 18 birds. Almost all the birds (92.1%) were juveniles.
(3) The records were made in 27 prefectures throughout Japan, and 80.5% of recorded localities distributed between 32°N and 36°N. The ibises were frequently observed at Gyotoku (Chiba Pref.), Yashiro (Hyogo Pref.), and Arasaki (Kagoshima Pref.).
(4) Almost all of them were feeding at marsh or margins of streams and pools 2 to 3km distant from the roost, associating with egrets.
(5) The occurrence of ibises was independent of seasons.
(6) The duration of staying of the ibises at the given localities was only one day in more than
half of the resords (54.5%); however, in some cases (7.7%), ibises stayed more than one year.
(7) Estimated population of the Oriented Ibis in the midto late Yedo era (1700-1850) seems to be large compared with that in recent years; however, there was no evidence of breeding in Japan.

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Field data from Burma May 6-11th, 1971 are given. Of special interests are the behaviour of Sterna acuticauda, and the relationship of Sturnus burmannicus towards Acridotheres tristis. In Pagon the breeding season was evident for many species.

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A survey of seabirds breeding on Teuri Island (44°25′N, 141°19′E) was conducted in July 1984 and April to August 1985. The numbers of breeding pairs were estimated as Larus crassirostris, 29, 466 : L. schistisagus, 414 ; Phalacrocorax filamentosus, 766; P. pelagicus, 12; Uria aalge, 217; Cerorhinca monocerata, 172, 041. Synthliboramphus antiquus and Cepphus carbo also breed on the island. The two Larus species and P. filamentosus have increased in numbers, while U. aalge and C. carbo have decreased recently.

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