In August 2003, we found new habitat of Salix hukaoana, a rare willow species that is endemic to Japan and designated as an endangered species Class IB, along the Ina River, in the Tadami River basin, Fukushima Prefecture, northern Japan. S. hukaoana is distributed from the confluence with the Tadami River for 45km along the Ina River and its branches and along the Kanoutsu River. The riparian forests containing S. hukaoana along the Ina and Kanoutsu Rivers were quite similar to the "Salicetum jessoensis Ohba 1973" and were classified into five types in a cluster analysis based on floristic composition. However, there were no significant relationships between the forest types, site condition, and stand age. All of the study stands were younger than 45 years old, and most showed a unimodal distribution of diameter at breast height (dbh), suggesting regeneration after a disturbance. S. hukaoana habitats have been lost with river engineering works. Therefore, countermeasures for the conservation of this species are urgently needed.

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We compared the aquatic fauna in ordinary rice fields, which are dry in winter, with those in lotus fields, which are flooded in winter. We carried out biweekly sampling of zooplankton and small aquatic animals at 15 pairs of adjacent rice and lotus fields in Ibaraki Prefecture, Japan, during the crop-growing season, when both types of paddy are flooded. Zooplankton were more abundant in the lotus fields than in the rice fields. The total number and biomass of small aquatic animals peaked in early June in the rice fields, but continued to increase in July in the lotus fields. In the rice fields, crayfish (Procambarus clarkii) dominated in May and tadpoles and insects dominated in June. In the lotus fields, Rana japonica tadpoles dominated from April to May and fish dominated from June to July. Some insects (Rhantus pulverosus and Berosus signaticollis), fish (Carassius spp., Pseudorasbora parva), and R. japonica tadpoles were more abundant in the lotus fields than in the rice fields, while dragonfly larva (Sympetrum spp.) and Hyla japonica tadpoles were more abundant in the rice fields than in the lotus fields. The observed differences in fauna may be the result not only of winter flooding but also of differences in water management and in the application of fertilizer and pesticides.

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To understand the views of nature held by undergraduate students training to be teachers, questionnaires were administered to 286 students in the Faculty of Education, at Shinshu University, in Nagano City, central Japan, in 2005. These questionnaires focused on investigating childhood circumstances, especially daily life and surroundings in childhood, and the ability to recognize common Japanese plants and trees. The questionnaire showed that many undergraduate students had lived in rural areas or had been in frequent contact with elderly people in their childhoods. There tend to be more opportunities for interacting with elderly people in rural areas than in urban areas. Specifically, the undergraduate students who had lived in rural areas, and who had been in frequent contact with elderly people, played outside more frequently as children than did those who had not had such experiences. They also had more knowledge of plants and their traditional uses, suggesting that childhood circumstances influenced their recognition of common species, to some extent. Conversely, there was no significant relationship between the recognition of other traditional plants and childhood circumstances. The main reason for this finding was that families stopped using traditional plants in their daily lives in the 1960s, and this, combined with a decline in plant habitats, led to the stagnation of a tradition that had been established between generations. Most of the undergraduate students stated that the cherry (e.g., Prunus×yedoensis) was a representative tree in Japan, followed by pine (Pinus spp.), cedar (Cryptomeria japonica), and cypress (Chamaecyparis obtusa), in that order. This trend was not significantly related to childhood circumstances. As typical trees in Nagano Prefecture, most of the undergraduate students recognized the Japanese white birch (Betula platyphylla var. japonica). Significantly, 60% of undergraduate students who mentioned "birch" came from Nagano Prefecture. Although the recognized trees were generally common species, most of the recognized trees, except for cherry, could have been derived from combining fragmentary knowledge and acquired images, rather than from the practice of tradition in their daily lives. Consequently, considering their roles in nature/environmental education as future schoolteachers, and based on the awareness of undergraduate students of nature as revealed in this study, it would seem that such knowledge should be included in teacher training. For example, to understand nature better, it would be effective to use familiar subjects related to nature, such as local customs, culture, and seasonal events. This would make it easier for undergraduate students to understand the relationships between nature and humans from an ecological perspective.

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As an example of educational activities about an invasive species that also comprised an effective study program in an elementary school, we report on the methodology and effects of a comprehensive study program that involved monitoring the distribution of Solidago altissima. With the assistance of an ecologist, it was concluded that: invasive species are effective materials for comprehensive study problems if an ecologist provides ecological information; the utilization of school curricula can enable continuous collection of ecological data; and educational activities about invasive species linked to school education are effective for both students and area residents. The report concludes with a discussion of the difficulties in turning the data obtained into scientific results and makes suggestions for solutions.

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Evaluation of the agricultural dependency of endangered biological taxa is important for their successful conservation and restoration. Here, we demonstrate an example of an evaluation method for agricultural dependency based on information provided in habitat records attached to vascular plant specimens in relation to fields for irrigated rice cultivation in Okayama Prefecture. For a total of 307 herbarium specimens, we compiled habitat descriptions of each taxon in irrigated rice fields. The data included 17 families and 22 taxa, of which 6 taxa were EN, 14 were VU, and 2 were NT. Habitat preferences were classified into six groups: (I) cultivated paddy field, (II) pond, (III) river and flood plain, (IV) paddy or river and flood plain, (V) paddy and pond, and (VI) all wetlands. Analysis of the agricultural dependency of RDB plants showed dependency on agricultural activity in the order of group: (I)>, (V)>(II)>, (IV)>others. With the exception of several RDB taxa in paddy fields, most plant taxa tended to depend on multiple wetland habitats. We must consider a more precise methodology to evaluate the agricultural dependency of RDB taxa, in order to promote systematic conservation and restoration of biodiversity in agroecosystems and their surrounding areas.

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Leptobotia curta (Japanese name, ayumodoki; English name, kissing loach) is a Japanese endemic freshwater fish that is distributed in only three river systems: two in Okayama Prefecture and the other in Kameoka City in the Lake Biwa-Yodo River system. It is one of the most endangered freshwater fishes in Japan. Leptobotia curta spawns on only one or two days, immediately after the rubber irrigation weirs are closed at the beginning of June. It spawns in limited areas where there is a muddy, richly vegetated river terrace zone with a gentle slope that has been temporarily submerged by rapidly rising water following operation of the irrigation weirs. The larvae need a suitable stable temporary water area for about 4 weeks, where they can eat daphniid zooplankton, but their environmental requirements during the subsequent developmental period from juvenile to adult are not strict. The prerequisite for the existence of this species is the presence of a suitable environment for spawning and for nursery grounds. Such environments occur in the coastal zone of flood plains or in flooded forest that is submerged by rapidly rising water during the rainy season in a monsoon climate. Such environments are called relict environments of the monsoon climate, and remain only in small areas, such as the retarding zones beside agricultural canals and on the terraces of small rivers in areas with gentle slopes located in conventional paddy-field areas. The reconstruction and maintenance of such relict environments of the monsoon climate are essential for species that depend on the conventional paddy field agriculture ecosystem, such as Leptobotia curta.

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Diving beetles inhabiting rice paddies and neighboring ponds are thought to be endangered due to various threatening factors. We investigated the regional red data book to evaluate the status of 133 species of diving beetles in Japan. Hydaticus satoi was already extinct from eight prefectures, Cybister tripunctatus orientalis from six, Dytiscus sharpi from four, and Cybister japonicus from two, indicating their high-risk status. Four common small-bodied species, including Laccophilus difficilis, are listed in the RDB of Kanagawa Prefecture. We evaluated the status of D. sharpi, for which information is relatively abundant, and found that all habitats known before World War II had already been developed. After the rediscovery of this species in Chiba Prefecture in 1984, several habitats were found in several prefectures. However, approximately 60% of the habitats have been lost since then. Several habitats remain in Ishikawa Prefecture but habitat loss due to the abandonment of rice paddies, development, over-exploitation, and invasion by alien species is of great concern. However, a number of conservation measures have been implemented, such as the flooding of abandoned rice paddies and the restoration of traditional farming practices.

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The Okayama race of Rana porosa brevipoda in the Sanyo region is one of the most endangered local populations of frogs in Japan. In 2003, it became clear that its habitat in Kannabe-cho in Hiroshima Prefecture would be lost because of a land readjustment project. Therefore, all individuals in the habitat were captured and kept in captivity. After the decision was made to reintroduce their offspring to a new habitat, paddy fields, our greatest concern was whether we could attain the understanding and cooperation of the farmer/landowners. Paddy fields provide a suitable habitat, but it would be necessary to control the water level in accordance with the frogs' life stage. A fallow field located in a paddy field area of Sera-gun, Hiroshima Prefecture, was selected as the reintroduction site, and 117 young and 2,947 larvae were reintroduced there in May and June 2004. Monitoring was conducted after the introduction, with 18 adults and 248 young (266 individuals in total) being recorded in October 2004. The following year, three clutches of eggs were found at the study site in June and 15 adults and 60 young (75 individuals in total) were recorded in October. We succeeded in establishing a sustainable population in the wild, while maintaining a reproductive group in captivity. In 2005, we selected a new site and reintroduced larvae. We plan to conduct another reintroduction at this site and continue monitoring to observe the sustainability of the population.

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