The distribution and breeding status of the Red-crowned Crane Grus japonensis were recorded from the air. Flights were made in a light plane over marshes, along rivers and lakes, in eastern Hokkaido from May 31 to June 2, 1986. Flying time totalled 15 hours and the distance covered was about 1, 810 km.
Fifty seven incubating and brooding paris were found; 47.4% of them were in Kushiro, 45.6% in Nemuro and 7.0% in Tokachi. In the Bekanbeushi area of Kushiro breeding pairs were much fewer than usual, but the reason was not clear. Though hatching occurred earlier in Kushiro than in Nemuro in 1984 and 1985, the ratio of incubating and brooding pairs was similar in both districts this year, suggesting that simultaneous egg laying or hatching occurred there. 40.1% of the population were engaged in breeding activities and the mean number of chicks per brooding pair was 1.33. By the survey date half of the non-breeders including juveniles had already moved from the wintering grounds in Kushiro to Nemuro.
From the air, 37% of the population in Kushiro were found in woods and on artifacts such as farm lands, roads, or banks, but less than 1% in Nemuro. Meanwhile 52.5% of the population in Nemuro were observed beside or in water, but only 19.6% in Kushiro. These observations indicate the difference between breeding habitats in the two districts. Excepting chicks, 275 individuals were observed, which were only 72% of the population counted at the feeding stations last winter. More precise surveys are necessary in the breeding season in order to locate the rest of the population.

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The upper plumage of nestling and fledgling C. saturatus horsfieldi and C. poliocephalus poliocephalus was similar, dark blackish brown (DBB) in the former and slaty black (SB) or DBB in the latter. The throat and breast were DBB in young C. s. horsfieldi, while they were banded with SB or DBB and white in young C. p. poliocephalus. The rest of the lower parts were banded with DBB or SB and white in both species, but the bars were obscure and much darker in nestling C. s, horsfieldi. The nestlings and fledglings of the two species in Japan are easily distinguished by the plumages of their underparts.

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Breeding bird populations in relation to vegetational changes by grazing were studied in a grassland in eastern Hokkaido from 1977 to 1979. During the study 39 bird species were recorded. Of them 13 species established their territories on the plot. After the grazing by cattle A. bistrigiceps and L, ochotensis were diasppeared, E. spodocephala and U. sibiricus decreased slightly, S. torquata and E. aureola did not change so much in densities, and A. arvensis increased slightly. Densities of other species remained low before and after the grazing. As a whole the total density decreased with the decrease in number of species. Open-country birds are affected through both changes in habitat and human-related activities influencing directly breeding succes.

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[in Japanese]

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[in Japanese]

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A dominance hierarcy of Motacilla wagtails (M. grandis, M. alba, and M. cinerea) and Water Pipits (Anthus spinoletta) was investigated on a stream in Utsunomiya, central Japan, in the winters of 1981-1983. An almost linear hierarchy existed among the species and between sexes, with ranking (most to least dominant) as follows: male M. grandis, female M. grandis, male M. alba, female M. alba, M. cinerea, and A. spinoletta. The proportion of victories by dominants was 100% except for a few encounters (5.7%) between female M. grandis and male M. alba. Dominance status was not necessarily related to their body sizes. Male M. grandis chased the other species more severely and more frequently than the others did.

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Between 1974 and 1983 the breeding of Little Grebes in autumn and winter was observed at the Shinobazu Pond, Ueno Park, Tokyo as follows: October(4 cases), November(1 case), December(2 cases), and January (2 cases). In all these cases they had successfully reared the chicks.The birds are probably capable of breeding at almost any time of the year and they started breeding when conditions seemed to be favorable.

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