Spacing patterns and winter dominance relationships, including tolerance, were studied among three species of wagtails (Motacilla spp.) along the Takano and Kamo rivers in Kyoto City, central Japan from 1981 to 1983. Japanese M. grandis and Grey Wagtails M. cinerea were observed throughout the year throughout the study area, while White (Black-backed) Wagtails M. alba (subspecies M. a. lugens) were observed from October to April in the lower part of the study area, which contained residential areas. The three species occurred in pairs or as solitary birds during the non-breeding season, with the proportion of paired birds (pair ratio) highest in M. grandis, lowest (zero) in M. cinerea, and intermediate in M. a. lugens. All of the social units of M. grandis, 87.1% of M. a. lugens and 70.0% of M. cinerea remained within a particular area for at least one hour (1-hr range) during winter. The 1-hr ranges were separated for conspecific birds, but overlapped among birds of different species. The units holding 1-hr ranges were pairs and solitary birds in both M. grandis (pair ratio = 87.5%) and M. a. lugens (pair ratio = 47.6%), but only solitary birds in M. cinerea. The mean body size of the species concerned was as follows: male M. grandis> male M. a lugens > female M. grandis > female M. a lugens> M. cinerea. A relative dominance relationship prevailed as follows: male M. grandis > female M. grandis > male M. a. lugens > female M. a. lugens > M. cinerea. However, the proportions of non-response of M. grandis toward M. cinerea were higher when M. a. lugens were near M. grandis than when no M. a. lugens were nearby; M. grandis tended to ignore M. cinerea in the presence of M. a. lugens. Primarily the body size, and secondarily the dependent status seem to determine the intersexual and interspecific dominance hierarchy. The difference in microhabitat, and interspecific relationships in dominance and tolerance may enable the three wagtail species to coexist in one area. Territory defendability resulting from such intersexual and interspecific dominance relationships is thought to determine whether a wagtail species occurs in a pair or not during winter.

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In central Japan, Eurasian Kestrels Falco tinnunculus nest in railway bridges. The relationship between their nesting density and the characteristics of the nesting sites and of the habitat were investigated. Eurasian Kestrels were found to nest either solitarily or in loose colonies. For each breeding site, the nesting density per site was noted, as were the width, height and number of entrance holes, and the length of the bridges where nesting occurred. The total area of each habitat (grassland, cultivated land, other grassland, rice field, residential area, bare land, water surface area, forest, fruits garden) was calculated using GIS (Geographic Information System) software. The nesting density per breeding site was 0.14-0.99 pairs/km², and was positively correlated to the total area of grassland and the bridge length. The results showed that the availability of suitable hunting grounds (grassland area) and nesting sites (bridge length) affect the nesting density of bridge-nesting Eurasian Kestrels.

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To determine energy budgets of captive Ural Owls Strix uralensis, 90 food consumption trials were conducted using three adult owls during September-October1995. Assimilated energy (AE) and energy assimilation efficiency (EAE) were determined, which depended daily gross energy ingested (IE), energy ejected (EE), pellet and feces energy loss per each day. Productive energy (PE) and maintenance energy (ME) were also determined. Energetic values of the diet, Apodemus speciosus, was 6.78±0.14kJ/g wet mass and 23.2±0.2kJ/g dry mass. Energetic values of daily pellets and feces were 13.2±1.1 kJ/g dry mass and 11.0±0.3kJ/g dry mass. The owls ate on the average 83.9±1.5 g of wet mass of A. speciosus per day. Mean AE was 447.2±9.1 kJ/day and EAE was 78.5±0.3 %. Mean AE per owl body mass was 0.702±0.014 kJ/g. They ejected 43.4±1.4 kJ (7.5±0.1%) as pellet and 77.3±1.2 kJ (14.0±0.3%) as feces. Mean productive energy was 5.2±1.0 kJ and mean maintenance energy was 442.2±9.0 kJ.

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To establish an effective and accurate method for measuring the locations of breeding Northern Goshawks (Accipiter gentilis) in central Hokkaido, we first took bearings from a transmitter placed in known locations. These sites were all located in a flat area in order to avoid topological effects on bearings. The average bearing error was 7.7 degrees using this method.
We then took bearings from a radio-tagged male goshawk from two fixed receiving stations situated 2.5km apart, and the goshawk's locations were calculated by means of triangulation. These locations were compared with goshawk's actual locations based on direct observations. This method revealed that the average bearing error was 29.6 degrees and the average telemetry error was 1.9km, indicating that telemetry errors using normal triangulation methods are too great to be of use in identifying habitat use in a mosaic landscape.
A further method was employed that involved tracking a radio-tagged goshawk by car until within 50m of it, and then attempting to maintain that distance. By direct observation and triangulation within this 50m range, goshawk locations were accurate to within a few meters.
During a 20-hour study period, we were able to maintain this range for more than half of the time, indicating the effectiveness of this method as a means of taking accurate locations of goshawks.

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Nests, eggs and chicks of the Japanese Wood Pigeon were found in two islets, Birou (32° 28′ N, 131° 44′ E) and Kobirou (32° 28′ N, 131° 44′ E), located at the northern coast of Miyazaki Prefecture, eastern Kyushu. We had found twentyfour nests between 1993 and 2000, all of which were built on the ground in thickets of Miscanthus condensatus, Pleioblastus simonii and Carex oahuensis var. robusta.

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