The Red-flanked Bushrobin Tarusiger cyanurus populations were censused along one to three 2-km transects (a total of 725) situated in 642 quadrats (5×5 km), in central and south-eastern Hokkaido from late April to early July, 1976-2004. Red-flanked Bushrobins occurred only in woodlands, 71 quadrats (11%) and 81 transects (11%). The occurrence frequencies were 92% in Pinus pumila forest, 54% in ever-green coniferous forest, 37% in mixed forest, 10% in broad leaved forest and 4% in Larix plantations. They occurred in more than 50m above sea level in eastern areas and in more than about 250m above sea-level in other areas. The numbers of birds (mean±SD) counted per 2-km transect were 2.5±2.4 in Pinus pumila forest, 0.4±1.0 in ever-green coniferous forests, 0.3±0.6 in mixed forests, 0.1±0.4 in deciduous broad-leaved forests, 0 in Larix plantations. Frequencies of occurrence were high in areas of low warmth index and low in aeas of high warmth index. Warmness is considered to be one of factors deciding the distribution of the species.

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The red-bellied tree squirrel, Callosciurus erythraeus, (common name : Formosan squirrel) has been introduced as a pet and naturalized in the suburban forests of Kanagawa Prefecture since the 1950 s. The study was conducted in 5.3 ha area in the forest of Yokohama Nature Sanctuary including various types of vegetation. Of 50 nests observed in the study area, conifer plantation and broad-leaved evergreen forests were preferentially used as nest sites. We collected 13 nests in May 2002 and 12 nests in January 2003, and the nest materials were examined. In outer layer of nests, the numerous twigs with leaves were used and included the tree species that the nest was established, such as, Castanopsis cuspidata, Quercus myrsinaefolia, and Chamaecyparis obtusa. Inner barks of conifer trees were most frequently used as inner nest materials. Mostly in winter, the middle layer made with large leaves (Q. serrata, Aucuba japonica) and outer barks of conifer trees were observed. The conifer plantation in suburban environments was important habitat for the alien squirrels in respect of nest sites and nest materials.

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I collected 7 individual of Sorex minutissimus hawkeri in the wetland of in Kiritappu Hamanaka-cho and in the sand area Kenbokuki Island. The capture record in Kenbokki is since S. m. hawkeri was already caught in Hichirippi, Hamanaka in 1985. S. m. hawkeri was captured until now was Wetland and a forest, this time they were caught in the sand area for the first time. The captures of this species were also recorded in Kunashiri, and Etorofu islands near Hokkaido. However the capture was no record in such a small island as Kenbokuki Island. S. m. hawkeri was observed eating beach fleas in a cage.

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Sorex minutissimus hawkeri of 9 individuals was caught in August, 2004 and September, 2004 on Kenbokki Island of Hokkaido. Nine individuals were caught, and among those, five individuals were alive and were caught. S.m. hawkeri was caught in the range from the position of 5 m to 15 m from the coastline. S.m. hawkeri made space between grass and was resting there. S.m. hawkeri rose and fell frequently to the grass upper part. Moreover, S.m. hawkeri might not move for tens of seconds to several minutes, where it is the grass upper part and the head is hung down downward.

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An annual fluctuation of population of red-backed vole has a typical pattern, that is, the population increases from spring to fall, owing to reproduction, then decreases to next spring. By the mark and release method the populations in one ha in Nopporo forest, Hokkaido, in about one year, were surveyed, measuring body weight which is useful for identifying age and checking reproduction state (pregnancy, lactating etc.). Cohort life tables were made on the base of month age, from which survival rates were calculated. Birth rate of each cohort was adjusted by the new born child numbers and reproduction state in the females. A month age distribution vector from each cohort at a given month projects to one at next month through the Leslie matrix with pertinent birth rates and survival rates. The comparison of age distribution vectors in the series of successive months is useful for discussing the process of annual fluctuation. The next paper will show that the numbers of outbreaks (for example, population density over 100/ha) which take place often in the Konsen district would be brought by the mere differences of the length of reproduction period and birth rate, and the age distribution at each time is useful for recognizing increasing or decreasing phase of population.

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Skylark, Alauda arvensis, is known as one of the most popular birds in palearctic grassland and farmland in North Asia and Europe. A decrease of the European race, Alauda arvensis arvensis, has been pointed out, which is possibly responsible to the recent decrease and deterioration of farmland. A decrease of the Japanese race, Alauda arvensis japonica, has also been pointed out. To establish the conservation ecology of the species, it is vital to clarify the ecological and habitat characteristics. There have, however, been little ecological and habitat characterizations of the present Japanese race. The author investigated its breeding status in grassland islanded by surrounding forests in Tokyo District. It was confirmed that, as a habitat suitable for breeding and feeding, a grassland must not only involve suitable vegetation, but also be situated with limited distance from the surrounding forest.

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A bat survey was carried out July and September 2003 and August 2004, in Shihoro River and Osarushinai River, in the central part of Tokachi, Hokkaido. Seven species of bats were caught in mist nets : Myotis daubentonii, Myotis ikonnikovi, Myotis frater, Epitesicus nilssonii, Vespertilio superans, Plecotus auritus and Murina ussuriensis. Among seven species, five species seemed to breed in this area, as suggested by the capture of lactating or post-lactating females (M. daubentonii, Epitesicus nilssonii and P. auritus) and/or the capture of yearlings (V. superans, P. auritus and M ussuriensis).

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Myotis daubentonii (Chiroptera) was first recorded from Sapporo, Ishikari and Tobetsu, Hokkaido in 2005, as the new westmost records in Hokkaido. During the survey we captured a young individual, which was born early this year and still nursed. Therefore, it is highly probable that the species breeds in the area around the Ishikari River. This species possibly uses hollow trees as its breeding sites around the study areas

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In field investigation of mammals, it is usually very difficult to obtain precise habitat information. To identify field mammals precisely I tried to use animal hair examination methods. Three observation methods were compared, that of the cuticular scales by SUMP method, that of the medulla structure by the prepared slide method, and that of the outer morphology under stereo-microscope. Twenty small-sized mammal species which belong to Insectivora, Chiroptela, Lagomorpha and Rodentia, were supplied as experimental materials. Result indicated that classification of the samples into the four Orders is easily made. Also it was possible to identify families in some orders. Specific identification within the same genus was not easy, but it would be possibile if more adequate data are available.

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Insects inhabiting on a riverbed suffer erosion by running water and flooding, thus sopposed to assume ecological characteristics of species inhabiting unstable environment. Polyphylla laticollis, a scarabaeid beetle, is an example of such species, found in the middle riparian galleries of the River Tama since early 1980's, but its biology has not been well-known. Investigation was carried out to estimate population size, using mark and recapture method, at three sites involved in two cities, Inagi and Tama. The population peak, as estimated by mark-release method, was the end of July, after which the population decreased. The numbers and sex ratio of adults captured by light traps at three survey sites differed considerably. Their flight began at around 19 : 00 and ceased at around 4:00 in July, with the peak at around 21:00-22:00. The time period of flight activity of males was earlier than that of females. The results suggest that large and small-size populations are distributed patchily along the river sides.

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Evolution is one of the important points of view for biological studies, but most of the biologists studying ecology of recent living organisms know little about extinct species. In this paper, I introduce Japanese fossil birds of the Cenzoic era, excluding Preistocene and Holocene. The Japanese Islands were separated from the Chinese Continent, and surrounded by the sea since Cenzoic era, and many fossil seabirds, including some largest species, have been dug out from Cenzoic strata in Japan. A penguin-like Pericaniformes, copepteryx, was found in Japan, one of which species was the largest Plotopterigidae of the world, and another one of which was one of the most completely preserved fossil specimens. Also unique Pelecaniformes, Pelagornithidae, had tooth-like bony structure and wings of 5-6 m long wing span. They have been found widely and from Oligocene to Pliocene and are thought to be important in considering evolution of Pelagornithidae. In addition, there were scores of fossil birds that were extinct, and they have close relationship with recent birds found in Japan. It is reasonable to suggest that Japan is one of the most important places in which many fossil birds were found for studies on evolution and biogeography of birds

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