Chelydrid turtles, i. e., snapping turtles (Chelydra serpentina) and alligator snapping turtles (Macroclemys temminckii), have been sold as pets and food around the world. It is estimated that tens of thousands of chelydrid turtles were exported from U. S. A. to Japan between 1989 and 2000. Possessing chelydrid turtles has been limited in Japan since 2000 because of the threat to human health. Moreover, because of the threat to native species in Japan, importing and possessing snapping turtles have been banned since 2005. Although feral turtles have often been found in the wild, there are few published data concerning their status in the wild. Review articles describing the current status of feral chelydrid turtles are thus useful to assess the risk of their establishment. I collected records of 208 snapping turtles and 129 alligator snapping turtles from January 1985 to December 2006 using news articles. The number of records of feral chelydrid turtles has been increasing, although laws that limit possession and trade of chelydrid turtles have been promulgated. However, reproductive populations seem to be rare at present because almost all cases were reports of single adult or subadult individuals, not those of hatchlings or juveniles. The risk of establishment of chelydrid turtles will remain for several decades because many turtles imported in the past seem to be still kept in captivity illegally. Utilization of news articles for monitoring feral chelydrid turtles is useful to obtain qualitative information, but we should be cautious in quantitative interpretations of them. We have to plan an effective long-term monitoring system and consider how to treat individuals kept illegally.

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We surveyed stomach contents of Rana japonica on the forest floor of a hill in Northern Yokohama, Japan. The frogs preyed mainly on macro soil animals and insects throughout the active season. A difference in prey items was found between adult and juvenile frogs; i.e., adult frogs preyed on Orthoptera and Lepidoptera larvae, but juvenile frogs ate ants and spiders. As for food resources in the research site, the adult frogs showed selective preference for Lepidoptera larvae and less preference for Diptera larvae, ants and Ispoda, whereas the juvenile frogs showed preference for spiders and less preference for Diptera larvae, collembolans, and mites. These results indicate that the factors for choosing prey items were not only gape size of the frogs and the body size of prey items but also selectivity and evasiveness of the prey

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2005年8月および9月に, 鳥取県と兵庫県にまたがる氷ノ山 (標高1510m) の頂上付近の登山道で, 雌のアカハライモリ Cynpos pyrrrhogaste 2匹発見した.発見場所の近くには水場はなく, 最も近い水場 (谷川の水源地および湿地沼) でも, 1km近く離れていた.いずれのイモリも, 四肢や指の形態, 体表の状況, 行動などに, 平地の水場で見られるイモリとは異なった, 陸上活動への影響と推察される特徴が見られた.例数は少ないが, アカハライモリは, ブナ林のような腐植層が発達した陸地であれば長期間生きていけるという可能性, また, 雌は繁殖水場を離れ, かなり遠くまで移動する性質があるという可能性を示唆する事例である.

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Rana porosa porosa wintering in a U-shaped concrete ditch along a paddy field were observated at Oba, Fujisawa City, Kanagawa Pref., central Japan. There was a little mud and dry grass in the ditch. When a concrete block in the ditch was lifted, the frog dug into the substrate and crouched there.

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