We studied nine marine mammal records from two old Korean texts, Chinese writting, Goshu-enjimon-chosen-sanko (Goshu's long, scattered manuscripts) and Chosen-Ocho-jitsuroku (A Korean True Account on the Monarchial Age). Four of the records were identified or assumed to be on the Japanese sea lion (Zalophus californianus japonicus) and five on larga seals (Phoca largha). The Japanese sea lion lived from the end of 17th c. to the beginning of the 19th c. and the larga seal from the 3rd c. B.C. to the end of 18th c. Two places where the sea lion are reported to have lived were Ullung-do in the Sea of Japan, and the estuary of the Tumangang in northeastern Korea, bordering on Russia. One place that the seal is reported to have lived was Kangnung located on the eastern coast of the Korean Peninsula. The other four places were somewhere around "the eastern waters", broad area containing the Bo Hai, Huang Hai and Sea of Japan. We confirmed that sea lions had had a breeding colony at Ullung-do at the end of 18th c., and estimate that their population size was substantial during three periods, the end of 17th and 18th c. and the beginning of 19th c.

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To analyze the status of wild boar (Sus scrofa), crossbred of pig×wild boar farming, and those feral populations, a written questionnaire was sent to 47 prefectural government offices, 679 branches of Dainippon Ryoyukai (Hunters Club) and 42 farmers. A verbal survey was also conducted on farmers in Gunma, Wakayama, Hokkaido, and Aomori prefectures. Breeding farms of wild boar and crossbreeds existed in 30 (63.8%) and 22 (46.8%) prefectures, respectively. The number of farms trippled between 1955 and 1964. It was the highest in the 1980s and the most popular motivation was to attract tourists. Feral crossbreds have been discovered in 36 prefectures (76.6%). The sources of feral animals were mostly unknown (69.8%). However, 0.9% of feral animals were reported to have been released intentionally. Almost half of the hunters (43.3%) surveyed responded to a question concerning their opinion of feral animals and they agreed to eliminate the animals. 23.0% welcomed them as hunting resources. Breeding was regarded as an industry that reinvigorated the local economy in Wakayama and Gunma prefectures. Delay of counter measures caused the feral crossbreed population to survive in Hokkaido.

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The same questionnaire survey was distributed to randomly selected tourists who visited Sanbonmatsu (SA) and Odashirogahara (OA), Nikko National Park, in order to analyze and compare tourists' characteristics and attitudes toward nature during the summer and fall of 1998. In total, 204 responses at SA and 202 at OA were obtained. The results indicated that the tourists who visited SA differed significantly from the ones who visited OA in several ways. Car-driving was the favorite among youth at SA. On the other hand, hiking was the favorite in aged at OA. The educational facilities are not frequently used though tourists have a strong interest in nature and a strong desire for understanding nature. Environmental education through visitors centers and interpretive signs on trails as well as first-hand knowledge about nature is not effective to increase tourists' awareness of nature and environmental protection.

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The geographical distribution and habitat characteristics of 11 arboreal land snails, subgenus Luchuhadra, including four vulnerable species, was investigated on the Amami, Okinawa and Miyako Islands. Most of the species except for Satsuma omoro (due to lack of sufficient observation) occurred more abundantly on Ficus virgata in natural woodlands. However, the vulnerable species, S. hemihelvus, was found not only within the woodland, but also in a public garden woodland maintained artificially. S. hemihelvus was mainly found on the underside of leaves, while S. sororcula was on the trunk of the tree. S. sooi, S. erabuensis, S. amanoi, S. iheyaensis, and S. hemihelvus showed limited geographical distributions, with less abundance, except for S. hemihelvus, which numbered more than 200 individuals at any observation site. On the other hand, S. largillierti and S. sororcula had many populations with high abundance.

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To analyze food habits, nutritional condition and these relationships of Japanese wild boar (Sus scrofa leucomystax), 260 stomach contents were collected between September 1994 and April 1995 in Iwami district, Shimane Prefecture, western Japan. They were analyzed using point frame methods (Leader-Williams et al. 1981). Dicotyledons was the most abundant food item in September and October (36.7%, 35.9% volumes respectively), however acorn became the principal food in October and November (26.3%, 25.3%). Root and tuber were the most preferred food between December and April (43.2-62.2%). Percentages of crude protein of stomach content were between 7.8% and 18.2%, which were beyond the optimal level specified for swine (National Research Council 1979) except February. Percentages of crude fat was 9.0% in September, increased to 17.7% in October, and then gradually decreased to 5.3% in February. Kidney fat index was also low in September (22.6%), increased to 48.2% in November, and then decreased to 25.3% in April. Acorn availability was thought to influence the nutritional condition of wild boars.

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Habitat selection of Japanese wild boars, Sus scrofa leucomystax, was studied by radio-tracking and analyses of activity sign distributions in Iwami district, Shimane Prefecture. Four radio-collared wild boars were located once a day during daytime from October 1994 to August 1997. All animals significantly preferred broad-leaved forest. On the other hand, three significantly avoided coniferous plantation. Activity signs were counted seasonally at 5 vegetation types during August 1996 to February 1999. At abandoned paddy number of rooting sites were found significantly more than other vegetation types, while those at coniferous plantation were significantly fewer through the year. Number of rooting site at bamboo thickets was also significantly more, but that at broad-leaved forest was significantly fewer in all seasons except fall. Population decrease and workers who progressively became old have caused increase of less managed broad-leaved forests and abandoned paddies in hilly and mountainous area, which provide favorable food and resting places for this animal. The socio-economic change may be one of the reasons of recent rapid expansion of wild boar in Shimane prefecture.

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