Avian vocalization during the total solar eclipse on 22 July 2009 was studied on Nakano-shima Is. in the Tokara Islands. Avian songs and calls were recorded using a digital voice recorder at three locations during the 6 min of totality and 1 hr each before and after the event. Vocalizations on the day before and after the solar eclipse were also recorded as controls (at two locations), and the numbers of songs or calls within each minute of the totality were counted for all recordings. A total of 17 species were recorded during the study period. The frequency of calls or songs averaged 16.4 per minute on ordinary days with a great difference between the days or locations and there was no silent period longer than two minutes. During the dark period, however, no diurnal birds sang or called in the study sites for 7 min 49 s on average. The Ryukyu Scops Owl Otus elegans was the only species recorded during the totality. The songs or calls of the Ruddy Kingfisher Halcyon coromanda and Ryukyu Robin Erithacus komadori increased shortly after the totality as at sunrise. However, the species turnover of songs that occurred in a dawn chorus was not detected during the totality. It suggests that the duration of the total eclipse was too short for birds to behave as they do during crepuscular periods.

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Over the last 20 years, the wintering distribution of the Rook Corvus frugilegus in Japan has been expanding. Records of Rook observations have been documented showing the expanding front line of their range. However, the process and causes for the range expansion of the Rook in Japan have not been discussed in the literature. A questionnaire survey as well as a literature study was conducted to collect information on their wintering ranges in Japan. Questionnaires were sent by email, inserted with a magazine delivery, and posted on a web site. The literature study was conducted by reviewing published scientific articles, bird check-lists for each prefecture, newsletters published by branches of the Wild Bird Society of Japan and other bird watching groups.
The results provided a time-line of the first sightings of Rooks in 19 prefectures. This information helped outline the process of how the Rooks wintering range has expanded in Japan. The wintering distribution of Rooks contracted during the late 1970's on the island of Kyushu, Yamaguchi and Shimane Prefecture. The wintering range of the Rook began expansion in the mid 1980s, and had extended considerably eastward along the Sea of Japan by the late 1980s. During the 1990s Rooks spread southwards from northern Japan as well, and by December 2006 they were confirmed to winter throughout Japan, except for in Tokyo.
The decrease of snow cover in Eastern and Northern Japan is probably responsible for the range expansion of Rooks wintering in those regions. However, there is not a strong correlation between annual snow coverage and the range expansion of Rooks throughout the remainder of the range. Some changes in farmland management may have allowed the species to spread its wintering range in Japan. The increase of Rooks breeding on the continent is likely have contributed to the expansion of the wintering range in Japan. Rooks were exposed to high levels of chemical compounds, such as organochlorines and organomercury in the past. As these pollutants have been restricted, the populations and ranges of Rooks have expanded in the Russian Far East. Therefore, the increase of the Rook population throughout East Asia due to decreased organochlorines and organomercury compounds is likely a key factor in winter range expansion of Rooks in Japan.

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We conducted the monitoring surveys of wintering Eastern Marsh Harriers Circus spilonotus and Hen Harriers C. cyaneus at their roosting sites in Watarase Marsh, central Japan between the winters of 1994 and 2009. The Marsh Harrier used two to seven sites as roosts and the Hen Harrier one to four during the survey periods. The numbers of the two species fluctuated greatly from year to year at the roosting sites due to disturbance resulting from reed harvest in the neighborhood, and from environmental factors such as the changes of vegetation conditions resulting from changes in the water level at the roosting sites. Although there were no great differences in the characteristics of roosting habitat between Marsh and Hen Harriers, the roost sites of the two harriers were segregated.
The peak abundances of the two harriers were reached during different periods, with Marsh Harriers in January and Hen Harriers in March. This suggests that some Hen Harriers arrive at their wintering grounds later than Marsh Harriers. A mean abundance of the Marsh Harrier was 30.44(6.90 SD) for a period of 16 years, while that of the Hen Harrier was 10.44(4.00 SD) for a period of 14 years. There was no significant correlation in abundance between the two species.
Population indices increased from 1.48 to 1.71 during 2005-2007 for Marsh Harriers, and from 1.85 to 2.14 during 2001-2003 for Hen Harriers. These increases were not, however, significant. The population indices increased by 2.3% per year for Marsh Harriers but declined by 4.9% per year for Hen Harriers. No other long-term monitoring surveys of these harriers have been conducted at any other sites in Japan, so we have no data with which to compare our results. The lack of similar studies in other areas limited our ability to determine the potential effects of some regional factors on the abundance of the harriers wintering in the study site. Therefore, a nation wide long-term monitoring program of these harriers is urgently required to determine their wintering population trends in Japan.

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In Japan, 16 White-tailed Eagles Haliaeetus albicilla have been confirmed killed in collisions with wind turbines. For Steller's Sea Eagles H. pelagicus, however, only one bird is known to have collided with a wind turbine. In order to determine why Steller's Sea Eagles collide with wind turbines much less frequently than White-tailed Eagles, we studied the flight behavior of the two species between 2007 and 2009 in Hokkaido, northern Japan.
The altitude of flight was significantly higher for Steller's Sea Eagles than for White-tailed Eagles, which frequently flew at altitudes within the height range for the rotor-swept area of wind turbines (50-100 m). The frequency of flight activity was also much higher for White-tailed Eagles than for Steller's Sea Eagles. These results confirm that White-tailed Eagles are at higher collision risk than Steller's Sea Eagles.
The flight altitude of migrating eagles was significantly higher than that of wintering and resident birds. It is suggested that measures should be taken to reduce collision risk primarily for wintering and resident eagles. Since migrating eagles generally fly at lower elevation when landing after their cross-ocean trip, however, they may enter the collision risk zone. Therefore, in areas where wind farms are located along points-of-arrival for migrating eagles, measures should be taken to reduce the collision risk for migrating eagles as well.

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We report the wintering record of a Rose-coloured Starling Sturnus roseus observed in Kochi city, Kochi Prefecture, Japan, from October 2008 to May 2009. This is the first record of this species from Shikoku Island. There are 14 records of this species in Japan, including this report, and most occur after the year 2000.

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Fluctuations of abundance in Bean Geese Anser fabalis were surveyed at wintering sites in Northern Japan, including Lake Otomonuma and the Hachirogata Lagoon in Northern Akita Prefecture, the Fukushimagata Lagoon in Niigata Pref., and Lake Kejonuma in Miyagi Pref. on 19 December 2008, and in 2009 on 9 and 23 January. The abundance of geese decreased in the Fukushimagata Lagoon and Lake Kejonuma while increasing in Northern Akita Pref. from 19 December 2008 to 9 January 2009. Subsequently, that pattern was found to have reversed on 23 January, 2009, when the abundance in Northern Akita Pref. had decreased and the abundance had increased at the Fukushima-gata Lagoon and Lake Kejonuma. Average temperature and total snowfall in Northern Akita Pref. was 0.1-0.5C and 66-79 cm, respectively, in middle and late January. Reduction of foraging efficiency due to increased snowfall would have prompted geese to move from Northern Akita Pref. to the Fukushimagata Lagoon and Lake Kejonuma.

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I recorded songs of an Asian Drongo-Cuckoo Surniculus lugubris at Mt. Tatsuta in Kumamoto, Kyushu, southern Japan on May 1 2010. This is the first audio record of Asian Drongo-Cuckoo songs in Japan. The species was identified by comparing the sound spectrogram of the recorded songs with that from a video and CD-ROM of an Asian Drongo-Cuckoo.

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We report the observation of a Snow Bunting Plectrophenax nivalis on top of Mt. Jirogyu (1,929 meters above sea level) in the Tsurugi Mountains, Miyoshi City, Tokushima Prefecture on 5 May 2010. This is the first record of the species from Shikoku Island.

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We studied White-tailed Haliaeetus albicilla and Steller's Sea Eagles H. pelagicus in western Hokkaido, along the sea terrace of the Japan Sea, to determine the factors affecting the frequency of flight activity. We analyzed the effect of nine factors (temperature, atmosphere, precipitation, hours of sunshine, wind speed, index of west wind speed, index of north wind speed, survey year and time of day) on the flight frequency of eagles. Index of west wind speed was the most important factors affecting the flight frequency of both White-tailed and Steller's Sea Eagles. Westerly winds interact with the slopes of the sea terrace to create favorable updrafts for flying.

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We developed methods to estimate the home ranges and important foraging areas of Northern Goshawks Accipiter gentilis, based on nest distributions, vegetation, and land-use patterns. We assessed the reliability of the estimation method by using radio-telemetry data on movements and locations of 19 pairs of Goshawks.
The assessment shows that the home ranges can be determined by Voronoi Partitioning based on the nest distributions. The important foraging areas were determined by the following steps. We first divided a goshawk home range map, including vegetation types and land-use, into a grid of 250 m x 250 m cells, and calculated the area of open habitat within 150 m of a woodland edge in each grid cell. The cells were then designated with a value weighted by the distance from a goshawk nest using seven weighting categories. We hypothesized that areas surrounded by grid cells within the upper 25 % of the resulting value ranges were important foraging areas (see Fig 4).
The estimated home ranges included 86.7% of perching locations on average, as determined by radio-telemetry location data. The important foraging areas that resulted from the estimation included 92.1% of 50% Kernel home range as determined through radio-telemetry. It is therefore reasonable to assume that the method based on an evaluation of nest distribution, vegetation and land-use does provide a reliable estimation of the home range and important foraging area for Northern Goshawk.

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It has been well known that tree sparrows Passer montanus ingest the nectar of cherry blossoms Prunus sp. without carrying pollen. This nectar-robbing behavior often causes cherry blossoms to drop prior to pollination. Since cherry blossoms are cherished in Japanese culture, some people are bothered by the nectar-robbing of sparrows. Here, we proposed a method by which to estimate how many blossoms were damaged by tree sparrows. In this method, we examined blossoms which had dropped on the ground under the trees, judged whether they were damaged by tree sparrows, and calculated the proportion that were damaged tree sparrows in relation to the total number of blossoms which had dropped. Applying this method to four study sites in Iwate Prefecture, northern Japan, we found that the number of the nectar-robbed flowers was very small (on the order of a dozen flowers / tree).

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