A survey for the Black Woodpecker Dryocopus martius was conducted by call-playback method between late 2007 to late 2009 in Nakagawa and Sorachi, Hokkaido, Japan. The survey was conducted to demonstrate the effectiveness of this survey method for the species, and to provide daily and seasonal detection data in the survey areas. Nineteen call-playback surveys were conducted in Sorachi, Hokkaido, during May, June and October of 2008, and in May, October and November of 2009. Each survey included between 6 and 25 call-playback stations at sites with suitable habitat in Mikasa, Naie, Kuriyama and Bibai. Surveys were also conducted monthly in Nakagawa, Hokkaido, from December 2007 to September 2008, and again during October and November of 2008. Black Woodpeckers were detected during surveys except in May and September. Both male and female Black Woodpeckers responded to the playbacks. Since Black Woodpeckers responded to both the recordings of calls and drumming, I recommend to playback the audio source of both calls and drummings. Cumulative detection rates of the Black Woodpecker were not significantly different during any season or time of day, although the detection rates seemed lower during the nesting season. After the playback was completed, Black Woodpeckers sometimes approached without calling. In the cases when I heard only the drumming sounds after the playbacks, I did not record that as an observation because I could not distinguish between the Black Woodpecker and the other woodpecker species

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Mortality of birds by entanglement in protective nets for agricultural lotus fields has been reported for such species as Green-winged Teals (Anas crecca), Eurasian Wigeons (A. penelope) and Common Coots (Fulica atra) in Ibaraki Prefecture, Japan. Monthly surveys were conducted on five days in lotus plantations at Lake Kasumigaura in the winter of 2010-2011. Fifteen species of birds were recorded entangled in nets, and a total of 185 individuals were observed to have died after entanglement. The rate of entanglement recorded during the survey was 7.5 +- 1.8 birds (mean +- SD) per 1 ha each day. The mode of entanglement in duck species (Anas sp.) was to be caught by the wings, while Common Coots were mainly caught by the legs and/or toes. The major agricultural periods during which bird were entangled were pre-harvest for Green-winged Teals, and post-harvest for Common Coots. Of 145 carcasses found entangled in the nets, 98 were not observed during the next surveillance day, so this suggests that the bird carcasses were likely to remain caught in the net, and therefore observable, for less than one month. Abundance of Ardeidae and shorebirds were negatively affected by the presence of nets, but Passeriformes did not show any reduction.

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Azure-winged Magpies Cyanopica cyana had a tendency to nest in association with Japanese Lesser Sparrowhawks Accipiter gularis to avoid nest predation, as described in the 1990s at a study site in Tokyo (Ueta 1994). During the 2000s, however, the hawks reduced the range they defended around their nest sites (Ueta 2007), and as a result, magpies no longer concentrated their own nests around the hawk nests. In this study, I examined the nest sites of magpies from 2005 to 2011 to determine why some magpies still nested in association with hawks in spite of the reduced benefit derived from parasitizing the nest defense of the hawks'. The 1990s study showed that Azure-winged Magpies nested in sites with less leaf coverage when associated with hawk nests. Presumably, the benefits derived from the hawk nest-defense were greater than the benefits derived from abundant coverage. During the 2000s, however. magpies nested in sites with a higher rate of leaf coverage, apparently to compensate for reduced nest-defense by the hawk. Without the benefits derived from parasitizing nest defense by the hawk, magpies selected abundant camouflage as a primary characteristic during nest-site selection. The leaf coverage at magpie nest-sites in the 2000s was similar between magpies that nested in association with hawks and those that did not. The magpie nests were found near hawk nests only where optimal nest sites (i.e. high percentage of leaf coverage) for magpies were abundant. This study concludes that magpies may nest in association with hawks only when there are optimal nest sites around hawk nests.

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Bird strikes on windows were surveyed in Amami Oshima Island. A total 63 bird strikes by 11 species were reported between April 2006 and March 2012. Bird strikes occurred throughout the year, without seasonal limitations, and the most frequent species to strike windows were Ruddy Kingfishers Halcyon coromanda (summer visitor), Whistling Green Pigeons Sphenurus formosae (resident) and Pale Thrushes Turdus pallidus (winter visitor). Threatened species such as Owston's White-backed Woodpecker Dendrocopos leucotos owstoni and Japanese Wood Pigeons Columba janthina were also killed in collisions with windows. For many casualties, the pectoral girdle (wishbone and coracoid) and the thoracic cage (vertebrae thoracicae, rib and sternum) were broken, and bleeding from lung, heart and liver was observed in most cases. Bird strikes occurred at large buildings such as tourist facilities, public facilities and schools. To reduce bird strike casualties at these facilities, it is important to disseminate information and raise awareness about measures that reduce bird strikes. Window and building designs that reduce bird strikes on windows should be required when constructing large buildings.

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Large birds that migrate by soaring are known to use updrafts created by topographic features. On the other hand, the behavior of birds that fly by powered flight are not well-studied. I observed the migratory behavior of crows (Jungle and Carrion Crows, Corvus macrorhynchos and C. corone) during March of 2008-2010 in western Hokkaido, along the sea terrace facing the Japan Sea to the west.
I observed that both species of crow flew along the sea terraces when the west wind created updrafts. When the east wind blew, however, crows flew along inland hills. Therefore, it is suggested that powered fliers such as crows also use updrafts to save energy during migration.

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The Japanese White-eye Zosterops japonica is known to rob nectar from several kinds of flowering plants. Hibiscus Hibiscus rosa-sinensis flowers damaged by nectar-robbing White-eyes were surveyed at three sites through the year on Okinawa Island, southern Japan, from June 2010 to May 2011. The rate of damage to flowers during winter was significantly higher than during other seasons. In general, White-eyes appear to rob nectar from Hibiscus in winter when the available food sources are scarce. At the urban study site, however, the rate during spring and summer was occasionally higher than during winter. The cause of this difference in utilization of Hibiscus flowers at urban sites is unknown, but may be due to a difference in flower varities or food resources. The urban site may also have more human disturbance that may affect the behavior of birds. When the cherry (Taiwan Cherry Prunus campanulata) was in bloom, the rate of damage to Hibiscus flowers dropped from 32% to 13% at all sites. Since White-eyes were observed to take cherry nectar during the cherry blossom season, they may not need to rob nectar of Hibiscus flowers during the height of the blooming season for cherry.

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I investigated the site fidelity of wintering Pintails Anas acuta at Shinobazu Pond in Ueno, downtown Tokyo, from November 1987 to April 1988. Pintails and other species of ducks were wintering in this site and have been fed by the Ueno Zoological Gardens since 1966. 68 male Pintails were given individual numeric codes by applying hair-dye to the white patch on the breast. The presence or absence of those individuals was recorded regularly throughout the winter. Use of the pond by marked individuals was not constant, with 6.7 of marked individuals being recorded on a daily basis during the fall when the duck population at the pond was increasing, and 9.1 being recorded daily during the sedentary period of mid-winter.

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I banded Tree Sparrow Passer montanus nestlings in the West Garden of the Ueno Zoological Gardens in central Tokyo from 1977 to 1995. The banded nestlings appeared to be over 9-10 days old. The average number of nestlings in the nest was compared with the banded years, banded months and the number of broods in the nest. The average number of nestlings in the nest were greater in 1970-1980th than 1990th. There were significantly different among banded years and months.

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I conducted a study of the effects of stream noise on local bird distribution in the breeding and wintering seasons between 2009 and 2012 in Oyama-sawa of Chichibu, Saitama Prefecture, central Japan. I set three study sites, each of which included survey points with and without stream noise, and counted the abundance of bird species within a radius of 50m. The general character of each study site was similar in terms of vegetation type and density. The sound levels (sound pressure waves) at each survey point were characterized by frequency and decibel range on an unweighted decibel scale. Sonagrams for the bird species encountered were created from data obtained during the study. In the breeding seasons, the number of Sakhalin Leaf-warblers Phylloscopus borealoides was significantly greater in the sites with stream noise, but the numbers of Eurasian Nuthatches Sitta europaea and Coal Tits Periparus ater were significantly greater in the sites free from stream noise. There was no significant difference in abundance between Eurasian Wrens Troglodytes troglodytes and Blue-and-White Flycatchers Cyanoptitla cyanomelana. In the wintering seasons, however, the abundances of Eurasian Nuthatches, Coal Tits and Willow Tits Poecile montanus showed no significant difference between the sites with and without stream noise. Sakhalin Leaf-warblers sang at frequencies higher than 6000Hz, which is little affected by the stream noise. Eurasian Nuthatches and Coal Tits, on the other hand, sang at lower frequencies than 6000Hz, which is greatly affected by the noise. Bird species that sang in a similar frequency range to the loudest stream noise (as measured by dB) demonstrated a shift away from the streams during the breeding season, while birds that sang in a higher frequency, at which the streams produce less noise, appear to either prefer near-stream locations or do not demonstrate a shift between sites. These results suggest that the stream noise may affect the local bird distribution in the breeding period through hindering the song communication.

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We observed a nest of the Black Paradise Flycatchers Terpsiphone atrocaudata attended by a female and two males in the forest of Nanatsumori, Shizukuishi Town, Iwate Prefecture on 9-11 July 2012. One male was a young adult, as indicated by short tail streamers, and the other was an adult with long tail streamers. Based on observation of aggressive behavior toward the male with long tail streamers, we assumed the younger male was the female's partner. It is not clear why the adult male with long tail streamers attended the breeding attempt. Further observation of the breeding behavior of this species with additional males is required, and DNA sampling would be helpful to identify the paternity in cases where two males were observed to care for the offspring in a nest.

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We made a preliminary study on analyzing the changing levels of bird songs of the day in order to determine the peak level time zone efficiently from massive sound recording data. The data were collected at nine sites of forests from Hokkaido to Kochi Prefecture, southwestern Japan. The bird songs were recorded for 80 minutes, e.g. from 20 min. before, to 60 min. after sunrise using IC recorders. Our analyses showed that the peak song period of the day was ten minutes, e.g. from four min. before, to six min. after sunrise. However, three species, such as Treron sieboldii, Eophona personata and Phylloscopus coronatus, sang frequently in the later period. In addition, long-distance migratory birds tended to start singing later in the day on their first arrival day. Therefore, we recommend monitoring forest bird songs twice a day, namely once around sunrise and later e.g. approximately 60 minutes after sunrise.

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Data for avian inventories were collected from three uninhabited islands in the Tokara Islands, which are locations with difficult access for research. I used three methods of identification for birds on the islands: 1) direct observation during a few hours on each island during one summer season, 2) infrared-triggered cameras, and 3) timer programmed sound recording systems. Remote systems both had more than a year of battery life, and were installed in forest habitat. The total number of species recorded was 40 on Gaja Island, 30 on Kaminone Island, and 28 on Yokoate Island. The number of species which were inferred to be breeding on the islands were 13, 9, and 8, respectively. Sea birds and herons seldom used the forest habitat, and they were recorded only by direct observation. The avian species whose data were recorded only by the automatic recording systems, which were approximately one-third of the total number of species on any of the 3 islands, were mainly migratory species that wintered or passed through those areas on migration. Data for most of the forest species that were considered as breeding on these islands were repeatedly recorded by several different methods. Only the sound recordings provided continuous records of the presence of singing individuals throughout the breeding season, which gives us a reliable basis to identify the breeding species. Automatic photo and sound recording systems still have problems regarding endurance in the field; nevertheless, they are powerful tools for avian inventory data collection at remote sites.

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This data set was aimed at monitoring the effects of climate change on forest bird breeding. The data were collected in forests of Chichibu (Saitama Pref.) and Shiga (Nagano Pref.), central Japan in 2011 and 2012. We currently know of no other data sets of forest bird song data that have been continuously collected during a breeding season, and we expect that this data set will provide useful basic information for various bird studies. Data were collected between March 1 to June 24 in 2011, and between April 1 to June 30 in 2012, for a total of 199 days during the two study periods. Bird songs were recorded for 90 minutes per day, and were identified to species. Several descriptive analyses to describe the pattern and frequency of bird songs of each species at different temporal scales are presented in Figures 1 through 3.Data download:http://www.bird-research.jp/appendix/br08/08r01.html

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