To evaluate how Lefua echigonia use paddy fields, we studied the so-called "yatsuda" paddy fields in Tokyo from April through November of 2006. The investigation consisted of trapping fish that migrate between the paddy fields and the irrigation channel, followed by a distributional survey at the channel. In the analysis, we compared the results of each item assessed for Lefua echigonia with those for Misgurnus anguillicaudatus and found that while both L. echigonia and M. anguillicaudatus bred in the paddy fields, the main breeding site for L. echigonia was apparently the channel. These results along with the observation that many juvenile L. echigonia enter the paddy fields suggest that the paddy fields function mainly as the growth place for L. echigonia. It was also found that L. echigonia tended to exit the paddy fields at the point of water entry.

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Our objectives were to produce a damage risk map (hazard map) to support countermeasures against damage to orchard fields caused by Japanese black bears (Ursus thibetanus japonicus) and to formulate conservation management plans. We investigated orchard fields at 116 sites in Shiwa Town, Iwate Prefecture, Japan, assessing whether the or chards had been damaged by bears and recording the orchard's environmental conditions. Furthermore, we analyzed the relationship between the damage and the environmental conditions in orchard fields using a classification tree model. We classified damage risk into the following three categories: (1) high risk of damage occurring in orchard fields in remote mountain areas with adjacent forests having an adjacency rate of greater than 53%; (2) moderate risk of damage occurring in orchard fields in remote mountain areas with adjacent forests having adjacency rates of 53% or less; and (3) low risk of damage occurring in orchard fields with no adjacent forest or where the forest is divided into smaller parts. To verify whether the model we used was appropriate, we validated the model. We confirmed that it is possible to generate a hazard map for orchards based on the environmental conditions of the orchard fields.

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The causes of the extinction of the Japanese wolf (Canis lupus hodophilax), once found in three-Honshu, Shikoku, and Kyushu-of the four Japanese large islands, were documented by surveying official documents of northeastern Honshu from the Meiji era (1868-1912). The results showed many instances of nuisance killings of the animals, motivated by attacks on free-ranging livestock by the animals. The extirpation policies and their implemental measures were planned and authorized by the prefectural administrations of Aomori, Iwate, Iwai (then occupying parts of both present-day Iwate and Miyagi Prefectures), and Miyagi. In Aomori Prefecture, the police killed wolves. In Iwai Prefecture, the police commanded hunters to conduct the nuisance killings. The government of Iwate Prefecture enacted a bounty system in 1875, and 201 wolves were killed in 6 years. The government of Miyagi Prefecture followed it in 1877. In Fukushima Prefecture, local people conducted nuisance killings. Besides, the documents showed that fur, meat, and other parts of wolves were traded and used in northeastern Honshu. Thus, it can be concluded that the nuisance killings and hunting of wolves in the late 19th century contributed to the extinction of these animals in northeastern Honshu.

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We studied the effectiveness of electronic deer whistles in scaring away sika deer that are likely to run onto roads, resulting in accidents. These whistles have been used in the U.S.A. and other countries. In this study, two types of deer whistles were tested: one that has a continuous tone with a fixed frequency (Whistle A) and the other that has an intermittent tone with a modulated frequency (Whistle B). To assess the effectiveness of the whistles in alerting deer, the deer's reactions to the whistles were observed by blowing the whistle from a fixed place that is visible to the deer when they appear by the roadside. For the control sample, deer's behavior when no whistle was blown was observed. When no whistle was blown, 51% of the deer were on alert about the observers. When Whistle A was blown, 67% of the deer were on alert; this figure increased to 95% when Whistle B was blown. The time durations for which the deer were alert when no whistle was blown, Whistle A was blown, and Whistle B was blown were 20%, 42%, and 73%, respectively. These results indicated that the deer whistles are effective in alerting deer, and that Whistle B is more effective than Whistle A. Vehicles can be equipped with deer whistles to alert deer about on-coming vehicles so as to prevent them from crossing roads, and consequently reduce deer-vehicle collisions.

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The hibernation sites of Rana rugosa were studied on a hill in Northern Iwaki, Fukushima Prefecture, Japan, in March 2006 and February 2009. Nineteen frogs were found hibernating in the pools and the backwater area of small stream (X ± SD = 13.0 ± 4.46 cm in depth, X ± SD = 1.56 ± 1.01 cm/sec in water velocity) where litter was accumulating thickly in a small stream. During the study, no frogs of this species were hibernating on land. In small stream of the hill, R. rugosa may mainly use areas slow-running water body or standing water body as hibernation sites.

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