Shrub-grassland bird populations were censused along four 2-km transects in grasslands along the middle reaches of the Ishikari River, central Hokkaido from late April to mid-July, 2009 to know adequate period for census to get information of breeding populations. Numbers of species recorded showed significant seasonal changes during the study period. Abundance indicated by the proportions of numbers of birds counted to the maximum number of birds during the study period also showed significant seasonal changes. Based on the results obtained, adequate periods for shrub-grassland bird census are May and June. Since song activities peak in May and June, it is desirable to conduct a census at least once a month in the months.

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Of various factors responsible for the diet selection of frugivorous birds, accessibility to fruit is assumed to play a major role. Swida macrophylla and Trema orientalis are sympatric species in Yakushima Island, Kagoshima Prefecture, southern Japan. Although their fruiting periods overlap, their morphological fruiting patterns differ greatly. Therefore, we studied the effect of accessibility to fruit on the diet selection of frugivorous birds. We established fixed observation points in the study site and also took morphological measurements of the birds. Bird species attracted to the fruit differed greatly between the two tree species. Ficedula narcissina and Hypsipetes amaurotis mainly visited Swida macrophylla and employed hover-capturing to eat the fruits. Zosterops japonicus, on the other hand, primarily foraged on Trema orientalis by hopping. A comparison of bird morphological features and fruiting patterns suggests that birds select trees which facilitate their access to the fruit.

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In May and June 2009, foraging behavior of two black-faced spoonbills Platalea minor was observed on a tidal flat of Ôhama, Ishigaki Island located in the southwestern part of the Ryukyu Islands. When one of the spoonbills was found in May, it had injured its left leg, but the leg appeared to have healed by June. They foraged in tidal pools (about 10 cm in depth) with dense green algae Ulva pertusa and a grayish black reduced layer exposed at the bottom due to eutrophication caused by in situ decomposition of U. pertusa . A large number of mandibles of Ceratoneris sp., belonging to polychaeta were found in the fecal droppings of Black-faced spoonbills. Ceratonereis sp., occurred only in the reduced layer with grayish black bottoms. These observations suggest that the injured bird postponed its northward migration until the leg was healed while chiefly preying on polychaeta in the tidal flat of Ishigaki Island.

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We investigated the colonial breeding of the Crested Myna Acridotheres cristatellus, an introduced species, using the weep holes of an artificial concrete wall in the suburbs of Yokohama City, Kanagawa Prefecture, central Japan. The wall contained 266 weep holes, 42 of which Crested Mynas used as nesting sites in early May 2008 and 18 of them were used again between late July and early August. The used holes had considerable space (more than 19cm in length) at the back between the end of the hole and the soil, while the unused ones had little or no space (less than 7cm long). The nestlings were mostly provided with insects (91% ), such as Coleoptera (beetles), Cicadae and Acrididae (locusts). The number of fledglings accompanied by their parents was less than three. It is assumed that the weep holes of an artificial wall are favorable to breeding Crested Mynas due to a low risk of the nest predation of crows and snakes as well as human disturbance.

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Forest bird surveys were conducted across Japan in the breeding seasons of 1994 and 1999. From the data obtained we calculated an interspecific similarity index of bird assemblage based on the presence and absence of species. The analysis revealed that birds were classified into four distinctive groups according to their sympatry. Group A consisted of 16 species, such as Garrulus glandarius , Parus ater , Troglodytes troglodytes , P. montanus , Sitta europaea and Luscinia cyanen . Group B was composed of eight species including Hypsipetes amaurotis and Zosterops japonica . Group C was comprised of three species, namely Hirundo rustica , Passer montanus and Sturnus cinera . Group D was made up of two species (Phasianus colchicus and Anas poecilorhyncha ), which were relatively uncommon in forest habitats. A similarity index ( φ ) was negative between Group A and Groups B or C, showing the bird species of the three groups are allopatric. Correlations between the MDS scores of 1994 and 1999 suggests that bird communities in the breeding season are stable over a period of a few years. Nationwide monitoring should be continued to detect the possible changes in bird communities in the national as well as regional levels so as to serve conservation aims.

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We found that bumble bees Bombus ardens Smith tried to breed in the nest boxes of Varied Tits Parus varius and Great Tits P. major by exploiting their nest materials. In almost all cases, bumble bees utilized completely built and /or egg-laid nests of the tits. It is possible that bumble bees displaced the tits from the nest boxes. However, they did not use the nest boxes of the tits in the area where a steep ridge blocked their flight way to their pollination sites. It is reasonable to assume that the ridge acts as a barrier to the bees collecting nectar, which discourages them from using the nest boxes in such a location. The nest materials of the tits would provide good insulation for bumble bees.

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I found a new plant species being added to the food list of the Bewick's Swan Cygnus columbianus . It is Cardamine scutata Thunb. , a herbaceous plant belonging to the Brassicaceae. I observed that a group of Bewick's Swans were grazing leaves and stems of the plant on stubble of rice fields in Echigo Plain where is a wintering ground of the swan, on 6th March, 1994.

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Protaetia brevitarsis (Lewis) (Coleoptera, Scarabaeidae) was detected from Ural Owl’s nests in Japan for the first time. We checked 37 nest boxes and two natural nests of the owl and found many larva in three nest boxes. The beetle larvae was feeding on the plant 72 matters (decaying wood chips, twigs and leaves) and the animal matters (e.g. remnants of food, bird feces and pellets) in the nests.

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We studied the breeding behavior of the Eastern Marsh Harrier Circus spilonotus in Hotoke Marsh, Aomori Prefecture, northern Japan from June to July in 2009. We focused on a nest containing two male nestlings and recorded their behaviors and food items by a video camera. The nestlings began to flutter at about 30 days of age and flew a short distance from the nest at about 39 days of age. They spent more than half of their time out of their nest at this period. They received foods from their parents in the air at about 45 days of age. At about 48 days of age they ceased to return to the nest. The video showed that the nestling diet consisted of small mammals (46%), birds (24%), frogs (12%) and unidentified prey items (18%). In addition, we analyzed the contents of 25 pellets, which showed that they included small mammals (70%), birds (27.5%) and insects (2.5%).

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We found an uncommonly large clutch of the Tree Sparrow Passer montanus in July 2010. Nine eggs were laid in a nest box at Ogata Village in Akita Prefecture, northern Japan. One egg hatched and successfully fledged, but the other eight eggs remained unhatched. The clutch included at least two eggs different from the others in color and pattern. It is known that Tree Sparrows lay the last egg different from the others of a clutch in color and pattern. The largest clutch ever reported for Tree Sparrows consists of eight eggs. It is, therefore, reasonable to assume that these eggs were laid by multiple females (including parasitic ones) or they belonged to different clutches laid by the same female.

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We studied Japanese Marsh Warblers Locustella pryeri wintering on the south coast of Iwate Prefecture, northern Japan from December 2008 to March 2009 and from January to March 2010. The species is listed in the Japanese Avian Red List as an endangered species. The study was carried out by using a playback and capture method. In the reedbeds of the mouth of the Unosumi River, 3–11 or 12 birds were continuously observed on each day throughout the study period. It is, therefore, reasonable to assume that this area was a wintering ground of this species. At each mouth of the Yoshihama and Sakari Rivers, however, only one bird was observed on each day in February and January. We presume that Japanese Marsh Warblers have wintered in the study site since 2002 when paddy fields were abandoned. This record shows that Iwate Prefecture is the northernmost wintering ground of Japanese Marsh Warblers.

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Information on potential hosts is essential for carrying out co-evolutionary research in cuckoo-host relationship. However, detailed information is available only for a few hosts because it is difficult to find parasitized nests thoroughly in the field. We found one parasitized nest each for the Asian Stubtail Urosphena squameiceps and the Eastern Crowned Warbler Phylloscopus coronatus in western Hokkaido. The Asian Stubtail was previously not known as a host species in Hokkaido. Although these two reddish parasitic eggs remained unhatched, it is most likely that the eggs were of the Oriental Cuckoo Cuculus optatus . One out of 67 nests of the Asian Stubtail was parasitized in this site in a total of eight years. On the other hand, five nests of the Eastern Crowned Warbler were found and three of them were parasitized in a total of four years. In this area, therefore, the Eastern Crowned Warbler is the main host and the Asian Stubtail may be a rare one for the Oriental Cuckoo. It is known that the main host of the cuckoo is the Japanese Bush Warbler Cettia diphone in central Hokkaido, however, the Oriental Cuckoo utilizes other host species in this area because of the low density of the Japanese Bush Warbler. Whatever the case, all the Oriental Cuckoo eggs found in Hokkaido seem to mimic the reddish eggs of Japanese Bush Warblers and not of other species.

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This paper provides the first record of Brown-eared Bulbuls observed in spring in the sub-alpine/alpine zone of Japan. This speciesBird is very common and resident all over Japan (including the footbase of Mt. Fuji), while there is no information about its visit to a sub-alpine/alpine zone. We report the seasonal abundance pattern of the Brown-eared Bulbul Hypsipetes amaurotis in the sub alpine-zone of Mt. Fuji, central Japan. Brown-eared Bulbuls were observed only on 3 days in late April and early May during the 40 surveys conducted between April and October 2003. This is a different seasonal pattern from 112 that of resident bulbuls in common habitats. The birds were observed in a flock (of 4-8 individuals) on the three occasions. Some previous studies of bulbul seasonal movements showed that bulbul populations consist of resident and migrant individuals. The bulbuls observed in the study site are most likely migrants because of their seasonal pattern and behaviour.

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[in Japanese]

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In 2009, we found an about twenty-day-old nestling of the Eurasian Honey Buzzard Pernis apivorus with a deformed left eye at Mt. Kimpo in Kumamoto, southern Japan. However, the chick fledged successfully in mid-August.

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In 2010, we observed an about one month delayed breeding of the Eurasian Honey Buzzard Pernis apivorus at Mt. Kimpo in Kumamoto, southern Japan. As in other years, however, the Eurasian Honey Buzzard came to Kumamoto in spring. We found a nestling which was about seven-days-old in a nest on 14 August. It seemed that the chick fledged on 18 September. Heavy rain in mid-July in the study area might have made this pair rebreed. On the other hand, good weather and high temperature in September probably contributed to the successful breeding.

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In 2002, I wrote a paper on the herb species that the Middendorff's Bean Goose foraged at rice fields around Lake Fukushimagata, Niigata Prefecture. It turned out, however, that the herb species might be Cardamine scutata . In this paper, therefore, I correct the herb species as Cardamine sp.

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