The tree sparrow Passer montanus is declining in Japan. The explanations so far proposed have not been tested. One possible explanation is that intensive urbanization negatively influences tree sparrow reproductive success. In order to examine this possibility, I compared the number of juveniles, and the number of fledglings cared for by one or two probable parent(s) between urban and rural areas in Kumamoto Prefecture. Results showed that the number of juveniles and the number of fledglings cared for by each pair of tree sparrows were lower in the urban area. These results suggest that tree sparrows suffer from factors affecting breeding success, such as shortages of food (seeds and insects) resulting from urbanization.

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The Wind Profiler, a meteorological radar for wind direction and speed, detects the 'bird echoes' that are returned mainly from migrating birds. We reported regional and seasonal status of bird migration by analyzing the echoes collected at 31 sites across Japan during the period from August 2003 to December 2007. The bird echoes were frequently recorded during April to June, and August to November, at all the sites. The peak seasons, however, were a earlier at southern sites in spring and later in autumn. The frequency of echoes increased 1-2 hours after sunset, and decreased after midnight. The time after sunset at which the echoes increased during autumn migration was frequently later than the time that they increased during spring migration, and the start time became earlier as the season progressed. Both spring and autumn migrations were frequently observed and recorded at sites along the Japan Sea, but sites along the Pacific coast frequently only had recordable autumn migrations. Combine bird ringing data, the Wind Profiler may allow us to monitor many aspects of bird migration across Japan.

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To examine the seasonal movement of Spot-billed Ducks Anas poecilorhyncha, fluctuation of the duck population was studied from October 2003 to April 2005 in Ono Reservoir, and from August 2004 to April 2005 in the nearby Katsura and Tsuru Rivers in Yamanashi Prefecture, central Honshu, Japan. The Spot-billed Duck population in the reservoir was highest during the breeding season from May to September, but the species was rarely observed during the wintering season from October to April. However, the remarkable decrease of the Spot-billed Duck population in winter was not found in the river. On the other hand, although Mallards A. platyrhynchos and other wintering ducks were observed in the reservoir, they were rarely observed in the river. Since interference by Mallards on Spot-billed Ducks has been reported, that could be one of the possible explanation of the observed phenomenon.

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A small bird and three Red Swamp Crawfishes Procambarus clarkii were found in stomach of a female Large-mouth Bass Micropterus salmoides (total length: 504mm, weight: 2.4kg), that was caught by net in Lake Uchinuma on 1st May 2009. The bird was identified as Reed Bunting Emberiza schoeniclus based on size and coloring of some feathers and length of upper mandible and tarsus.

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Micro-habitat selection within rice fields by Bewick's Swans Cygnus columbianus was investigated at Nishi- Kambara District in the Echigo Plain, Niigata, on December 11, 2004 and February 26, 2005. Swans preferred foraging sites in the basins of rice fields over sites along dikes and waterways. Statistical comparisons showed that the birds were observed to forage in basins at a greater frequency than would be expected if they were distributed at an equal rate in both micro-habitats. Conversely, birds which were not foraging were observed along dikes and waterways more often than predicted by chance. The area size of basins is much larger than the area for dikes and waterways, and this differential is addressed by the statistical method.

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To predict the most hazardous areas for collisions with wind turbines by greater white-fronted geese Anser albifrons around their stopover sites, the relationship between flight altitude of geese and the distance from takeoff sites was studied at lakes Izu-numa and Kabukuri-numa in February 2009, the period when the geese started their spring migration. The model showed that the geese reached a low risk altitude, over 100m, at 3km from the takeoff sites. It suggests that the risk of collision with wind turbines by greater white-fronted geese decreases to a minimum in areas further than 3km from stopover sites, because most wind turbines currently used are less than 100m in height.

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The effectiveness of point counts and route censuses in quantifying abundance and richness in bird species was analyzed for data collected at 13 woodland sites during four periods, including wintering seasons from late December 2005 to February 2006, and late December 2007 to February 2008, and breeding seasons from mid-May to mid-June 2006 and 2007. The number of species detected by point count was more than that of route census both during winter and breeding seasons. Moreover, species detection rate during point counts was higher, with shorter survey time, than the detection rate of route censuses. Although there were significant positive relationships in the maximum number of individuals for each species detected using point counts and route censuses in both seasons, the abundance of each species was difficult to compare between point counts and route censuses in winter. Since the sum of the maximum number of individuals recorded at each survey location during point counts was highly correlated with the maximum number of individuals recorded by route censuses during the breeding season, the relative abundance of each species could be compared with each other when using either method. Considering the higher species detection rate of the point count method, the higher total number of detected species, and the similarity of abundance data between the methods, the point count is recommended as the preferred survey method for monitoring population trends when comparing relative abundances of bird species.

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The platform transmitter terminal (PTT) is a locational telemetry device usually used for satellite tracking birds. The method of attaching a PTT using a harness system of Teflon-treated ribbons sometimes causes injury to the wing membranes of Great Cormorants Phalacrocorax carbo through abrasion of the skin by the ribbon. A Tesa-tape system is expected to decrease the probability of injury, although the durability of its adhesion has not been known. Therefore, we examined the durability of a Tesa-tape adhesion system by using dummy PTTs made from acrylic board. We captured six semi-domesticated cormorants and four wild cormorants and attached the dummy PTTs to the backs of the birds using Tesa-tape. Semi-domesticated cormorants were captured in March 2004 and in May-June 2006, and wild individuals were captured in October 2006. We attached the dummy PTTs to these cormorants, and observed them intermittently to determine the duration of adhesion. For seven of the ten cormorants, the date on which the PTT fell off was known within an error margin of 10 days, and those observations are presented here. The attachment durations of the dummy PTTs were divided into two categories: less than 30 days and more than 60 days. The longest attachment period was 81 days, but we have not deduced a reason that explains the varying attachment durations. When the dummy PTTs were attached to three semi-domesticated cormorants just before the molting season, however, two of them fell within 5 days. Therefore we recommend avoiding the molting season when attaching the PTTs with the Tesa-tape system, and we conclude that an attachment method using Tesa-tape is not durable enough to last for the three months to a year that is typically necessary for satellite tracking of cormorants.

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The effectiveness of point counts in quantifying abundance and richness in bird species was analyzed for data collected at 10 grasslands sites during three periods, including a breeding season from mid-May to mid-July 2007, and two wintering seasons from late December 2007 to February 2008, and late December 2008 to February 2009. There was no significant difference between the two methods. The point count method tended to have a slightly better detection rate than that of route census both during winter and breeding seasons. There were significant positive relationships in the maximum number of individuals for each species detected using point counts and route censuses in both seasons. The abundance of each species, on the other hand, was difficult to compare between point counts and route censuses. Since the sum of the maximum number of individuals recorded at each survey location during point counts was highly correlated with the maximum number of individuals recorded by route censuses, the relative abundance of each species could be compared with each other when using either method. Considering the higher species detection rate of the point count method, and the similarity of abundance data between the methods, the point count is recommended as the preferred survey method for monitoring population trends when comparing relative abundances of bird species.

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