Oshima Ohshima Island, located at 41°30′N, 139°22′E in the Sea of Japan, is the northernmost breeding place of streaked shearwaters (Calonectris leucomelas) in Japan. At present, the breeding population size is estimated to be as small as only a few hundreds. To clarify past human exploitation of the shearwater on this island, information obtained from 25 elderly fishermen who once engaged in seaweed gathering was examined. Between 1921 and 1967 on Oshima Ohshima Island, a total of about 300, 000-410, 000 streaked shearwaters were killed for food by fishermen who were gathering seaweed "wakame" (Undaria pinnatifida). Although the heavy annual exploitation of streaked shearwaters on this island stopped in 1967, no definite signs of recovery of the breeding shearwater population have been observed since. This is probably due to occasional poaching, breeding disturbance by feral rabbits (Oryctolagus cuniculus), which compete for burrows and prevent the development of bushes and forests, and predation by Norway rats (Rattus norvegicus). Of these, the feral rabbit seems to have had the strongest effect in preventing the recovery of favourable woody nesting sites for the streaked shearwaters. To assist in the recovery of the breeding streaked shearwater population on Oshima Ohshima Island, removal of feral rabbits and Norway rats from the nesting sites of shearwaters is thus recommended.

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Since 1985 a flock of gray starlings (Sturnus cineraceus) has roosted annually from June to October at Doho Park, Tsukuba City, Ibaraki Prefecture. In the summer of 1994 all the birds were repelled from the site after their distress call was presented through a loudspeaker on five consecutive evenings. The birds then constructed roosts at several new sites including a park and street trees within 5.2km from the original site. The majority of these roosts did not persist for more than one month, except for roosts in tulip trees (Liriodendron tulipifera) planted along a street running beside the park which were occupied for 3 months. Roosting sites in the tulip trees were separated into smaller aggregations.

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Landscape structures of three areas of Higashi-lyayama Village, in the eastern Shikoku Mountains in Shikoku, Japan, are compared in 1954, 1975 and 1989/1990. The landscape structure of the Tsurugi area has become heterogeneous. There have been no settlements in this area. The matrix of natural Fagus crenata forest has been segmented by newly induced patches of coniferous plantations. In Ochiai and Mibuchi areas in 1954, patchy landscapes composed of different successional vegetations were established due to cyclical forest use, such as slash and burn agriculture. In 1975, the landscape became more heterogeneous because a new coniferous plantation appeared in the abandoned slash and burn fields. After 1975, the landscape became homogeneous because of the growth of the forests. The trends in landscape change in Ochiai and Mibuchi were similar, though the Ochiai landscape was more heterogeneous. The differences in landscape heterogeneities were correlated with differences in social size.

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The scat contents of feral dogs (Canis familiaris) were compared between two periods (1973-1975 and 1993-1994) before and after an increase of sika deer population in Nikko, central Honshu, Japan. Among five food items, sika deer (Cervus nippon) was found to be the main staple food during both periods. In the first period, before the population increase of sika deer, however, the occurrence of sika deer in scats decreased from 66% in winter and spring to 19% in summer and fall, next to human leftovers. In the second period after the recent population increase of sika deer, sika deer comprized 78-96% and was ranked at the top throughout the year, while human leftovers declined to only several percent. Thus, sika deer and human leftovers were likely in a trade-off relation. Small mammals occupied a small portion. Natural plant fractions may have been eaten with the digestive organs of sika deer.

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The biomass of undergrowth and food availability for Sika deer (Cervus nippon) were measured by a quadratic method (1m×1m and 2m×2m in size) in clear-cut, unplanted stands of 2-8 years of age and young sugi (Cryptomeria japonica) plantations of 2-24 years of age in Fudakake, Tanzawa Mountains, central Honshu, Japan, in 1974. The biomass of available food decreased from over 200g/m^2 (Dry) two years after clear-cutting to a level of 50% to 70% lower 8 years after clear-cutting due to the dominance of an unpalatable plant (Miscanthus sinensis) and other woody plants. The undergrowth biomass exhibited a similar trend. The biomass of undergrowth as well as the biomass of available food was significantly larger in moderately moist brown forest soil (B_D) than in eroded soil (Er). In sugi plantations having the B_D soil type, the undergrowth biomass and available food biomass were reduced by yearly weeding to the levels of the Er soil type.

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