Morphological features of the taste buds and the distribution of the taste pores of the Large-billed Crow Corvus macrorhynchos were investigated by scanning electron microscopy (SEM) and light microscopy (LM). SEM revealed two types of openings on the oral epithelium of the Large-billed Crow. The larger type (more than 50 μm in diameter) was spiral or spindle shaped, while the smaller type (less than 10 μm in diameter) was circular in shape. The former corresponded to the opening of the salivary glands, and the latter to the taste pores, as revealed by conventional LM. An average of 537 (SE = 38.4; N = 4) taste pores were observed, of which 82% were located in the lower mandible and 18% in the upper mandible. The anterior part of the tongue was found to be devoid of taste buds and pores. In addition, taste buds were found to be composed of three cell types: light, dark, and sustentacular.

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To assess the effects of the Great East Japan Earthquake (2011) on the life of Brent Geese Branta bernicla, the wintering distribution of the geese was investigated along the southern Sanriku Coast from Hirota Bay (38°59′N, 141°38′E) through Rikuzentakata to the estuary of Kitakami River (38°34′N, 141°27′E), Ishinomaki in the winter of 2011-2012. Geese were counted in the study area in late November to early December 2011 (291), early January 2012 (380), and late February 2012 (403). The number of observed Brent Geese was not substantially different from population data prior to the earthquake. In late November to early December 2011 and in early January 2012, larger numbers of the geese were observed in the fishery harbors (59%) than on the sea (35-41%). It is suggested that the geese began using fishery harbors (where they had only rarely been observed prior to the earthquake) due to: (1) wharfs in harbors that had subsided during the earthquake being subsequently washed by sea water and covered with seaweed, providing a new food resource to the geese, (2) reduced fishery activity in the damaged harbors and hence reduced human disturbance, and (3) farming facilities in coastal waters for Wakame (seaweed) Undaria pinnatifida and Oysters Crassostrea gigas, which had previously provided the geese with seaweed, having been lost during the tsunami. In late February, more geese were observed on the sea (63%) and on the sandy beaches (21%), presumably resulting from the growth of seaweed on the farming facilities resettled after the earthquake, and newly available seaweeds on sandy beaches. It seems likely that the geese adapted to large-scale environmental changes caused by the earthquake through shifting their foraging habitat and overwintering areas.

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The Eurasian Tree Sparrow Passer montanus is common in both urban and rural areas in Japan and often nests in spaces of man-made structures (e.g. electric transformer boxes, under eaves). Therefore, differences in the designs of such artificial structures and their spatial distributions between urban and rural areas could influence the breeding ecology of the Eurasian Tree Sparrow. In this study, we compared (1) nesting site, (2) number of breeding attempts in a season, (3) nest re-use and (4) spatial distribution of nests, of tree sparrows between urban and rural areas. In our urban study site, birds nested most frequently in spaces in transformer boxes on telephone poles. At our rural site, birds preferred to nest under the eaves of houses. Differences in ecology were also detected between urban and rural sites. There were three breeding peaks in the urban area, but two in the rural area. Nest reuse was more frequent in the urban area than in the rural area. The spatial distribution of nests was random in our urban study site, but aggregated in our rural site. These differences may contribute to differences in the strength of individual interactions and reproductive success between urban and rural sites and could help explain the differences in the abundance of this species between environments.

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Eurasian Tree Sparrows Passer montanus were studied in rice fields from the perspective of rice Oryza sativa ripeness and distance between rice fields and residential areas. Bird censuses were conducted, using the line transect method, and the condition of rice fields was assessed, during mid- and late August in southern Ibaraki and northern Chiba prefectures. The effects of two variables on the appearance of tree sparrows were examined using generalized linear mixed models. Our results suggest that fully ripened rice had a positive effect on the appearance of tree sparrows in late August. The distance between rice fields and residential areas had a negative effect on the appearance of tree sparrows in both mid- and late August. Thus, we conclude that tree sparrows tended to appear in fully ripe rice fields or in rice fields near residential areas.

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The avifauna of farmland in the Tokachi district of Hokkaido, Japan was investigated. A total of 1,252 individuals of 26 species was observed in 10.5 ha of oat and potato fields and wooded windbreaks. Only three species attempted to nest. Eurasian Skylark Alauda arvensis was the dominant species, with a mean territory density of 0.36 pairs/ha. The avifaunal diversities of the oat field and the potato field were lower than that of the windbreaks, while the oat field and potato field avifaunas more closely resembled each other than that of windbreaks. Skylarks did not breed in the crop fields until mid-June, by which time the crops had matured.

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We investigated the nest location and breeding activity of the introduced Chinese Hwamei (Melodious Laughing thrush) Garrulax canorus in 2009 and 2010, at Minami-Ohsawa Campus of Tokyo Metropolitan University, located in the western Tama Hills, Tokyo, Japan. Nests were found not only in secondary mixed-forest, but also in more artificial environments such as garden shrubs and hedgerows. The average height of nests was 139.3 ± SD 44.57 cm (range 90-208 cm, N=10) above the ground. The breeding season of the Chinese Hwamei was mainly from April to July. We color-ringed three nestlings in one successful nest in 2009, and, of them, one male bred successfully in this study area in summer 2010. This male was re-found in the same area in September and December 2010, and November 2011. These results are an example of the short-distance natal dispersal and breeding success of a yearling male Chinese Hwamei.

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A major problem facing outdoor electrical power apparatuses is that certain bird species peck at external polymeric insulation materials, such as silicone oil compounds and silicone rubber. In order to develop countermeasures and prevent electrical failure, we investigated this issue by performing Fourier transformed infrared (FT-IR) spectroscopy and DNA analysis of pellet fragments. The results showed good matching between base sequences of DNA from the pellet and that of Corvus macrorhynchos. The ingredients of the synthetic materials in the pellet corresponded to silicone oil compounds. We thus showed that C. macrorhynchos feeds on such silicone materials. Moreover, we suggest that the reason why birds feed on silicone materials differs from what has been hypothesized so far, i.e., seeking acid oils.

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Food remains incidentally regurgitated by four maturing Black-footed Albatross Phoebastria nigripes chicks on Torishima (30°29′02″N, 140°18′11″E), Izu Islands in mid-May 2000, were identified. All four chicks regurgitated mesopelagic nektons: four squid families consisting of Architeuthidae (Architeuthis sp.), Chiroteuthidae (Chiroteuthis sp.), Cranchiidae (Megalocranchia sp.) and Sthenoteuthis oualaniensis (Ommastrephidae), as well as Chiasmodontidae fish (the first record as prey of Black-footed Albatross) and Notostomus japonicus (an Oplophoridae shrimp). Albatross parents probably scavenged these prey items from the ocean surface, when these mesopelagic organisms (either moribund or dead) surfaced, possibly as a result of human activities, foraging activities by marine pursuit predators, or for other reasons.

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Few studies have been made so far of inter-colonial and annual variation in the diet of breeding Great Cormorants Phalacrocorax carbo. We investigated their diet during the chick rearing period by collecting regurgitates from five breeding colonies, in the Chubu area, central Japan, in 2009-2011. Those cormorants breeding in coastal colonies took mainly Flathead Mullet Mugil cephalus cephalus and Dotted Gizzard Shad Konosirus punctatus, while those breeding in inland colonies took a wide range of fishes in any given year. The frequency of introduced Red Swamp Crayfish Procambarus clarkii and native Oriental River Prawn Macrobrachium nipponense in the diet increased in years when frequencies of fishes decreased, at both inland and coastal colonies.

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