To evaluate the condition of agricultural damages by Japanese wild boars (Sus scrofa) and Japanese monkeys (Macaca fuscata), and farmers' attitude toward it, a questionnaire was conducted in Yamanashi Prefecture in 1998. There were 338 respondents, and the response rate was 56.3%. Both wild boars' damages, mostly to rice, potatoes, and corns, and monkeys' damages, mostly to persimmon, pumpkin, soybean, and potatoes, increased rapidly in the Heisei era (1988-). Most of the farmers hoped to decrease or exterminate boar and monkey populations, and few of them supported the idea to make compensation system or to build fences around their farms. Respondents who would maintain their farming consist 41.7%, however 32.5% would shrink their activity and 25.1% would abandon it. Respondents suffering damages thought to shrink or abandon their activity significantly more than the other respondents (X²-test, p < 0.05).

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The effects of burrow-nesting by streaked shearwaters (Calonectris leucomelas) on the growth and survival of Persea thunbergii seedlings was studied in a warm-temperate evergreen forest on Kanmurijima Island, Kyoto, central Japan. The author used 20 protected and unprotected plots to explore seedling survival and growth. The P. thunbergii seedlings that survived the disturbances of burrow nesters were significantly taller and had a larger leaf area than those of dead P. thunbergii seedlings. Seedlings of this species were found to have a small total leaf area, independent of the height growth, in comparison with seedlings of the same species in forest areas not used by streaked shearwaters. These results at the seedling stage suggest that there is a strong relationship between lower survivorship of P. thunbergii seedlings and the negative effects on seedling growth caused by burrow-nesting disturbances. This paper also discusses the conservation of the warm-temperate evergreen forest as suitable habitats for streaked shearwaters.

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The authors studied the likelihood that seeds were being dispersed by the Japanese black bear (Ursus thibetanus japonicus) in a deciduous forest near Ashikawa Village, Yamanashi Prefecture. The forest was composed of 113 tree species. Japanese black bear ate fruits and seeds belonging to 37 species (including 7 unidentified). About 86.7 to 99.7% of seeds identified in 360 samples of bear feces were in good condition for 17 species (10 drupes, 5 berries, 1 multiple fruit of droplets and 1 pome). However, no intact seeds were found for 5 nut species. The germination rate of Yamasakura (Prunus jamasakura) seeds taken from feces was the same as for uneaten seeds. The results of this investigation suggest a high likelihood of seed dispersal by the Japanese black bear.

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The authors studied the status and attitudes toward agricultural damage caused mainly by wild boar (Sus scrofa), through interviews in 2001, with 134 farmers and local hunters of wild boar in Minami-Izu, Shizuoka Prefecture. This mountainous and forested area has complex topography, covering 11,058 ha at the southern tip of the Izu Peninsula, and is inhabited by 10,500 residents. Ten percent of the area is used for agriculture, which was the third largest employer in the area. Since the 1970s, agriculture in this town rapidly declined in both cropland area and the number of farming families, while the proportion of older farmers increased. Fifty percent of farmers had no income from agriculture at the time of the study, while only 5% obtained an annual farm income over five million yen. Sixty-seven percent of farmers had no planned successors, while 56% intended to reduce their scale of farming in the future because of their advancing age. Crop damage caused by the animals occurred in most parts of the study area. Farmers tended to take costless and labor-saving countermeasures for this problem. Most local hunters were over 50 years of age and their planned successors were few in number. Although the numbers of animals taken had increased rapidly in recent years, crop damage had not decreased. The authors concluded that farmers may disappear from this area in near future and most of the cropland may return to natural conditions favorable to wild boar and other wildlife habitat.

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