A follow-up survey of dandelion plants (Taraxacum) in 1990-1992, ten years after the initial survey using the same site designation methods in the southern Kanto district, revealed the following facts. Firstly, in the Tokyo urban area, the occurrence of both dandelion species had little changed; that is, the introduced one dominated there. Secondly, in the suburban areas, the number of lots in the recent survey where the native diploid species dominated had decreased compared with the previous survey, whereas the number of lots where the introduced species dominated had increased. Third, analysis of land-use in the two surveys revealed that a sharp decrease in cultivated fields, which are preferred by the native diploid species, caused a 48.7% drop in this dandelion's occurrence in the suburban areas. The count of the introduced dandelions also dropped by 3.5% in southern Tama, one suburb area. This species decreased in sites such as roadsides and vacant areas that have diminished, and increased on areas such as parking lots and children's playgrounds that have been expanded over the last ten years. These findings clarified the fact that decreases in habitat resulted in the retreat of ranges and declines in the frequency of occurrence for both dandelion species in the urban and suburban areas.

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Food habits of the Japanese marten (Martes melampus) were studied by scat analysis, and 11 questionnaires send to camp-site managers in Hinode-cho and Akiruno-shi, 50 km west of Tokyo Metropolitan district, between October 1997 and November 1998. In this area martens mainly ate fruits, insects and small mammals but not human food remains. A similar trend was found when 4 other studies in Kisokomagatake, Nikko, and Tsushima were compared with this data by using cluster analysis.

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A questionnaire was conducted to analyze hunters' attitudes toward the hunting condition, hunting regulation and wildlife in Yamanashi Prefecture. There were 327 respondents, and the response rate was 59.5%. Wild boar (Sus scrofa) was the most popular game species, and nuisance animals tended to be selected. The average age of respondents was 56.1 ± 9.6 (SD), and hunters older than 50 years of age made up over fifty percent. The annual number of days spent hunting tended to decrease, and that main reason was "busy with other activity". The shortage of hunters was the main problem of the present nuisance control system. But neither the hunting association nor the administrative agencies have actively tried to recruit new hunters.

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宮城県北上町十三浜沿岸における海藻相の季節変化と成熟季節の特徴を明らかにするために, 1998年4月から1999年2月まで海藻を採集した.採集した海藻は, 緑藻6科8属13種, 褐藻15科21属28種, ならびに紅藻20科38属61種の合計102種であり, 海産顕花植物はスガモ(Phyllospadix iwatensis)1種であつた.小型1年生海藻は周年10種以上が成熟した.小型多年生海藻の成熟種数は秋季から冬季に多かった.大型多年生海藻の成熟季節は, ヒバマタ目褐藻の夏季とアラメの秋季から冬季に分けられた.

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1998年11月から1999年10月まで福島県いわき市下神白沿岸において生育する海藻を採集し, 種の同定と生殖細胞の有無を観察した.採集された海藻は, 緑藻3科5属7種, 褐藻7科13属19種, 紅藻18科38属57種の合計83種で, 海産顕花植物のスガモ1種を含めて総計84種の海産植物の生育が確認された.生活形ごとの成熟種数は, 小型1年生海藻が周年最も多く認められ, 小型多年生海藻と大型多年生海藻は夏季から秋季に多く認められた.海中林の造成のために海藻礁を設置する適期は, 各生活形群が最も多く成熟する夏季であると考えられた.

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