In areas with high sika deer density the loss of regenerated vegetation at previously deforested sites, due to herbivory, is a serious problem. However, there are plant species with anti-herbivory strategies, such as Hypolepis punctata, that form a relatively large community at deforested sites under severe feeding pressure by sika deer. This suggests that planting H. punctata may be effective in improving the revegetation of such places. In order to evaluate the effectiveness of revegetation using H. punctata, we investigated stands of the H. punctata community and areas of bare ground at deforested sites in the southern part of Awaji Island in Hyogo Prefecture, Japan. We also investigated secondary forests in the vicinity of the deforested sites. The stands of the H. punctata community were similar to the secondary forests with regards to soil depth and soil chemistry. Soil erosion was clearly observed at the bare ground sites. The number of forest species per 25m^2 was higher in the stands of the H. punctata community than in the secondary forests. Comparison of species composition between the three types of site showed that most species found in the secondary forests were also present in the stands of the H. punctata community. These results suggest that the H. punctata community has a high capacity to reduce erosion and maintain forest species richness. Thus, we concluded that H. punctata is a useful species for the revegetation of deforested sites that are under severe feeding pressure by sika deer.

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Witches'- broom of bamboo, caused by the fungus Aciculosporium take (Cavicipitaceae), is the most destructive of bamboo diseases. We investigated disease incidence and bamboo damage resulting from the disease, particularly in Phyllostachys bambusoides and P. pubescens communities, in western Japan. Our investigation revealed that in 17 prefectures, 93.2% of P. bambusoides communities had the disease, and that in 10 of the prefectures several P. bambusoides communities were severely damaged. In contrast, only 3.9% of P. pubescens communities had the disease, and in six prefectures the disease had not infected P. pubescens communities. However, in a supplementary investigation, we found numerous infected P. pubescens communities in the Shizuoka Prefecture in central Japan, but few of these communities were heavily damaged. These results indicated that the number of P. bambusoides communities killed by witches' broom of bamboo may increase in the near future throughout western Japan, and that the disease rarely kills P. pubescens communities.

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To study the impact of the local extinction of a large frugivore species on plant populations, we compared the seed dispersal of the large-seeded tree Myrica rubra in two forests. One forest had a population of Japanese macaques, which are large seed dispersers of M. rubra, and the other did not. Observations were made from 25 May to 7 June, 2004 on four trees on Yakushima Island (with macaques) and three trees of Tanegashima Island (without macaques). The total observation period was 137h 30min (Yakushima Island: 73h 46min, and Tanegashima Island: 63h 44min). M. rubra trees were primarily visited by Japanese macaques (Yakushima Island) and brown-eared bulbuls (both islands). The mean number of fruits consumed per visit by the macaques on Yakushima Island was 20 times more than that consumed by the bulbuls on both islands. In short, the mean number of fruits consumed per day per tree on Yakushima Island (Total: 918.1 fruits; macaques: 893.0, and bulbuls: 25.1) was higher than that on Tanegashima Island (bulbuls: 24.0). These results suggested that macaques may be the 'keystone' seed dispersers for M. rubra, and that the reduction in macaque numbers may lead to a decrease in the number of seeds dispersed from these trees.

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One of the main aims of conservation ecology is to conserve ecosystems under human influence. Consequently, many conservation projects require correspondence between conservationists and members of the public. However, few examinations of this social-scientific exchange have been conducted. In this paper we examined local environmental history in a reed bed along the lower Iwaki River in Aomori Prefecture, Japan, and determined that local social change with regard to the use of natural resources is an important factor in landscape formation. This paper discusses the mutual relationship between society and nature, and the monitoring of that relationship. We report that ecologists must consider local 'right' owners who have managed natural resources thus far when executing conservation projects, as it is important for these owners to accept the management plan. Ecologists must also take into account the probable influence conservation projects will have on local communities. These social dimensions should be a target of the social-scientific monitoring that should be a part of adaptive management systems, together with natural-scientific monitoring.

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To understand the current conditions of threatened plants in Hakone, Kanagawa, we analyzed flora data collected by Hakone Park volunteers from 2002 to 2006. During this time a total of 830 plant species were recorded. Thirty species were designated as national Red List species and 34 were assigned a Prefecture Red Data Book designation in Hakone. Nearly all of these species were considered susceptible to human activities. Twenty-six of these species have not been observed for more than two years. Nine of the unobserved species were Orchidaceae species. When all Orchidaceae species in the park were analyzed, it was determined that over half of these species were threatened. These results suggest that the national park area is an important area for the protection of species especially susceptible to development. Human collection is a major factor contributing to plant extinction. We concluded that park volunteers are imperative for conservation within national parks, as they provide invaluable information about species that can lead to solutions for conservation problems.

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We investigated paddy-rice cultivation type and its effect on Rana nigromaculata and Fejervarya limnocharis in the Tyuyo district, Ehime Prefecture. The distribution of both frog species was examined in 2005, while paddy-rice cultivation distribution was monitored from 2000 to 2005. We used maps that had paddy-rice cultivations diagramed by type in 1958 and compared them to maps from 2000-2005. We found that many of the paddy-rice cultivation types from 1958 had changed to short-term cultivation in the lowland area on the plains in 2000-2005. In contrast, the same change had not occurred in the mountain area, but the breed of cultivated rice had changed. When the effect of altitude on the frog species was examined, we found that F. limnocharis was mainly found in the lowlands and that R. nigromaculata did not show a clear tendency in relation to any altitude. R. nigromaculata was rarely detected at sites having short-term paddy-rice cultivation types; however, F. limnocharis was often detected at one such site. F. limnocharis was not influenced by the shortening of the irrigation period. From these results we concluded that R. nigromaculata was more strongly affected by paddy-rice cultivation type than by altitude, and that F. limnocharis was more affected by altitude than by cultivation type.

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We investigated the growth of the juvenile horseshoe crab Tachypleus tridentatus, an endangered species, at the Tsuyazaki mudflat in Fukuoka, Japan, from September 2003 to October 2006. In doing so, we developed a monitoring method for this endangered species. Growth was estimated by carapace width (CW) frequency analysis. The CW frequency was separated into four instars with a CW range of 17.00〜62.00mm. Each unimodal distribution area showed the CW ranges from 5 to 8 instars. The mean CW of juvenile horseshoe crabs increased 1.35, 1.33 and 1.31 times with each molting process. These values were higher than the growth rate under the rearing conditions from a previous study. If captured individuals were divided into age groups according to the CW ranges obtained from this study, it would be possible to monitor the increase and decrease of the threatened wild population. The endangered horseshoe crab could be an important flagship species in the conservation of the coastal ecosystem because diverse coastal environments are necessary for its life cycle. Therefore, to protect the endangered horseshoe crab species and its natural habitat or biodiversity, the citizen-based monitoring of horseshoe crabs should continue in this field.

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We investigated distribution and habitat preference of a threatened plant, Penthorum chinense Pursh, in the tidal compartment of the Kiso River. The study site was located in the transitional area of the floodplain between a natural levee and delta. Our field survey revealed that many P. chinense individuals occurred at higher elevation sites, where the Salix chaenomeloides community predominantly exists, although there were no traces of disturbance. This suggests that P. chinense does not depend on a disturbance for its establishment. This is contrary to studies in other areas. To determine the preferred conditions of P. chinense we investigated the relationship between six environmental factors and growth and flowering using model selection with maximum likelihood estimation. Our results indicated that sediment surface hardness was the most important factor. The open quaggy sites with ground surface sediment hardness of 0.16-0.82kg/cm^2, 20-60% RPPFD at 3m, inundation of 3.97-5.84h/day, a fine sediment depth of 32-40cm on the ground surface, a median diameter of 0.048-0.053mm for sediment and sediment sorting coefficients of 1.24-1.79 were most suitable for growth and flowering. Although the environment was similar, P. chinense population density was low at lower elevations, where other herbaceous plants dominated. Since submergence or saline stress cannot be regarded as the limiting factor, interspecific competition is likely to be important in the spatial distribution of P. chinense along the elevation gradient within the floodplain.

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Stachyurus macrocarpus var. prunifolius is a single-island endemic shrub of Haha-jima Island (Ogasawara). For a long time there was only one known individual shrub, and this was the primary problem in the conservation of this species. However, in October 2007 another shrub population was discovered. The individuals of this population were identified as S. macrocarpus var. prunifolius, based on morphological characteristics of its leaves and fruits. It occupied a subtree open-forest habitat on a slope located near old-growth forest. This discovery is important for conservation management planning and, additionally, to more accurately describe the species' characteristics. This said, the species population is still at a critical level because of its small population size. Moreover, the population is being suppressed by the invasive tree, Bischofia javanica, which is becoming a threat to the newly discovered habitat. Restoration of the shrub population and careful eradication of B. javanica is necessary for the conservation of this endangered species.

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The Skylark Alauda arvensis is one of the most common grassland bird species in Japan. However, several reports suggest a decline in A. arvensis populations due to habitat loss, especially in urban areas. Therefore, factors affecting species distribution in relation to habitat preference in conservation planning must be evaluated. We did this by constructing habitat models to predict suitable breeding habitats for Skylarks in Tokyo using observation records collected in the 1970s and 1990s. The model predicted breeding occurrence in the 1970s and viability from the 1970s to 1990s using a GLM. Nine vegetation types and their combinations were used as predictor variables, along with a neighborhood effect. Our results showed that variables of aggregated 6 grassland types and the neighborhood effect significantly affected breeding occurrence in the 1970s. Viability was significantly affected by wet and dry grasslands in the 1990s. Since both models were relatively accurate, we applied the models to a map and revealed that 1) Skylarks were potentially widespread in Tokyo in the 1970s, and 2) grassland habitats along the rivers and coastline served as refuges in the 1990s due to the decrease in grassland habitat resulting from urbanization. Thus, conservation and restoration along the waterfront are imperative for Skylark viability in Tokyo.

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In 2001 the Hokkaido Regional Development Bureau (HRDB) published the "Proposal for Conservation of the River Environment in Kushiro Mire" (a Ramsar site). One of the 12 themes of the report was that of controlling the vegetation of the mire, specifically, the increase in black alder distribution and decrease in reed and sedge colonies, which are river environment indicators. HRDB carried out a large-scale (over 200ha) field experiment to raise the groundwater level by closing the Setsuri sluice in the Yasuhara River area from September 2000 to May 2003. During this time, the alder forest occupied only a small part of the flooding area, and changed little. However, our surveys from 2004 found that much of the original sedge and reed vegetation was replaced by a new community of Bidens and Persicaria species, typical of a disturbed riverside environment. This type of vegetation had never been recorded before in the Kushiro Mire. It is important to learn from this case so that future attempts at restoration can be more successful. Such projects should clearly allocate responsibilities and be based on sufficient preliminary surveys and predictive models.

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In order to determine the present state and potential conservation strategies of the endangered Pteridophyta, Polystichum neolobatum Nakai, we investigated whole individuals, leaf size and habitat for the species. P. neolobatum was found in only two of the four sites it had previously been observed in. Only 21 individuals were found in 2004, 18 individuals in 2006, and 15 individuals in 2007. There were two mature individuals with spores found on three different occasions. Eleven individuals were found in places where sika deer could enter (ET) and seven in places where there were no sika deer (NS). There was no difference in the average leaf number per individual between ET and NS sites, but leaf size was smaller at ET sites, as compared to NS. Furthermore, individuals at ET sites more frequently lacked the tip of their leaves, which sika deer may have ingested. There was less vegetation cover and a lower frequency of Sasamorpha borealis at ET than at NS sites. These findings suggest that P. neolobatum may be facing extinction in the Tanzawa Mountains. To conserve P. neolobatum, deer-proof fences must be established to prevent sika deer from browsing on forest floor vegetation, and propagation technology must be developed as an emergency measure.

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During the autumn and early winter of 2004, mass sightings of the Asiatic black bear, Ursus thibetanus, were recorded near human residences from northern to western Honshu. These mass sightings were caused by the failure of acorn crops, which serve as an important food source for bear over-wintering. We analyzed hairs from 95 bear individuals collected during a project implemented by the Environmental Ministry of Japan in 2004. Twenty of these specimens (two bears from Korea and 18 from Japan) were analyzed at successive 3-mm intervals, from the root to the tip of the hairs. Samples from Korea exhibited typical patterns of δ^<13>C and δ^<15>N: δ^<15>N values were high at the tip of hairs, increased in middle sections, and then decreased toward the root. These patterns were strongly associated with ecological observations that bears consume young leaves in the spring, catch insects during the summer, and then primarily consume acorns during the autumn. In contrast, patterns of δ^<13>C and δ^<15>N in Japan exhibited geographical variation: in some areas of western Japan, values of δ^<15>N rapidly increased at the root. The analysis of the hair roots of 95 bears indicated that individuals from the northern and central Alps, Northern Kinki, and western Chugoku had higher δ^<13>C values, suggesting a diet of C_4 foods, such as corns and related food residues. Some individuals from the Chugoku and Kii areas exhibited higher values of δ^<15>N. However, δ^<15>N values exhibited geographical variation; thus, sampling and δ^<13>C and δ^<15>N analyses of successive portions of bear hair are necessary for more thorough nutritional diagnoses.

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We investigated mammal fauna and changes in the seasonal habitat of sika deer using camera traps at three sites on Mt. Ohdaigahara in Central Japan. We set up a total of 19 automatic cameras at nine points in the eastern area, seven points in the southeastern area, and three points in the western area in late June to late November, 2002, and in late April to late September, 2003. We obtained pictures of four orders and eight species of mammals: Japanese macaque, Japanese giant flying squirrel, Japanese red fox, raccoon dog, Japanese marten, Eurasian badger, giant forest hog, sika deer, and some unidentified bat species. There were 913 camera days in the eastern area, 1,561 days in the southeastern area and 729 days in the western area. Sika deer comprised 95.2% (2,837 times) of the mammals photographed at all points, followed by the Japanese macaque at 3.1% (93 times). The numbers of other photographed mammals were remarkably low. In the eastern area sika deer made up 99.0% (2,043 times) of all mammals photographed. However, in the southeastern and western areas, species other than sika deer comprised 12.6% and 16.3% of the totals, respectively. The Japanese giant flying squirrel was only camera-trapped in the southeastern area, while the Eurasian badger only in the western area. There were no mammals photographed at some points in the eastern area and points in the southeastern area that bordered the eastern area. As a trend, sika deer in the eastern area increased in numbers from spring to summer and decreased in the fall. In contrast, sika deer increased in the fall in the southeastern and western areas. These results suggest that the eastern area, which is dominated by dwarf bamboo grassland, has conspicuously more sika deer and low mammal fauna diversity. The southeastern and western areas have more mammal species diversity than the eastern area, but the numbers are lower.

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