In the south basin of Lake Biwa, Japan, the area and standing crops of submerged macrophyte vegetation were largely fluctuated due to the influence of human activities since 1930s. Vallisneria asiatica var. biwaensis (Hydrocharitaceae) is an endemic submerged macrophyte in the Lake Biwa-Yodo River system, Japan, and its populations have decreased in the south basin since the 1970s. In this study, population genetic structure of the species was analyzed to evaluate current status of the genetic variation and its relationship to the population reduction. A total of 447 samples from 19 populations, mainly located in the south basin, were genotyped at 14 allozyme loci. The levels of genetic variations in the south basin populations are almost consistent with that of the north basin populations. Low genetic differentiation among the populations suggests the occurrence of high gene flow, while the presence of population grouping along the coast was observed in the south basin. Our results demonstrated the limited relevance of the population reduction to its population genetic structure. However, protection of the genetic variability of the species is required from a conservation genetic viewpoint. The population genetic structure revealed in this study would be useful information in conservation program development.

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The involvement of a wide range of stakeholders in conservation actions is essential for achieving lasting conservation efforts at a large spatial scale. This issue was one primary focus of the Aichi Biodiversity Target endorsed at the COP10 of the Convention on Biological Diversity. Citizen participation is particularly important given the potential for addressing a wide spectrum of issues concerning biodiversity conservation. To facilitate such participation, it is necessary to understand how behavioral intentions toward conservation actions are determined and which factors play important roles in this process. Here, we examined how awareness of ecosystem services affects the behavioral intentions of citizens to engage in conservation efforts. We designed a questionnaire asking individuals to rate their awareness of various ecosystem services on a scale of one to five. Data were collected from 5225 people through an internet survey. Using structural equation analysis, the data were used to test a decision-making model modified from an existing social psychological model to incorporate causal paths from awareness of ecosystem services to behavioral intentions toward conservation actions. Our results demonstrated that awareness of only one (cultural) of four (basal, provisional, regulation, and cultural) types of ecological services significantly facilitated positive behavioral intentions toward conservation efforts. Additionally, the social physiological terms "consciousness of social norms" and "consciousness of cost of the activity" had significant positive and negative effects, respectively, on behavioral intentions. Moreover, these relationships were robust regardless of the degree of urbanization of the area in which the respondents lived. These results suggest that improving citizen awareness of ecosystem services, especially cultural services, is likely to facilitate participation in conservation activities.

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Practical, scientific criteria are needed for selecting reserve areas. Therefore, we evaluated conservation priority to determine the most important habitats of grassland birds. We constructed habitat models to predict the distributions of 29 grassland birds in Chiba Prefecture using bird survey records and habitat data (areas of seven grassland habitat types and neighborhood effects) at 57 sites. We used patches as a unit of analysis to consider connectivity. Logistic regression models were constructed based on species presence/absence at every site as the response variable and the combination of habitat types at seven connection distances as explanatory variables. Then, we selected the best models using the Akaike Information Criterion (AIC). The observed and predicted showed good agreement (≥70% accuracy for 22 species). Moreover, previous knowledge indicated that this method extracted the essential species habitat. We proposed the Conservation Priority Index (CPI) as a criterion for evaluating habitat importance. Then, we plotted the CPI as a map. The high CPI values of paddy fields indicated their importance for grassland birds. As a result, we propose to conserve the paddy fields in Katori and Tako, with the highest CPI. This study proposed an improved species distribution model and the CPI, a new criterion for selecting reserve areas.

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We investigated seasonal flower visitation, brood size, and honey storage in captive colonies of the Japanese honeybee Apis cerana japonica to quantify the species' provision of satoyama ecosystem services. Research took place near Ichinoseki City in Iwate Prefecture, Japan, where the Kubokawa Ihatov Nature Restoration Project has been initiated to restore satoyama biodiversity. Periodic census data on floral visitation and contact with floral reproductive organs revealed that A. c. japonica may pollinate up to 45 native plant species, three crop species, and two horticultural species. In spring, A. c. japonica workers frequently visited herbaceous plants in fallow paddies and along paddy ridges. Bees favored various trees of the deciduous broad-leaved forest during summer and intensively foraged Fagopyrum esculentum (buckwheat) fields during autumn. Pollen analysis performed in spring revealed that most pollen was foraged from deciduous trees. Periodic inspection of captive colonies showed that A. c. japonica colonies grew mainly during June and September. These periods may be most suitable for assessing potential honey supply services.

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Identification of focal areas for conservation using hotspot analysis is an effective method of biodiversity conservation planning. In this study, we identified and compared hotspots for various environmental stressors and habitat types based on the extinction risk of vascular plant species outlined in the Red Data Book of Japan (2000), at the secondary cell scale (〜10×10km). Because survey bias may influence the apparent effectiveness of conservation efforts in a given area, we statistically evaluated the effect of survey effort. We showed that effective areas for conservation comprise various habitat types. According to a cumulative logit model using conservation effect calculated from vascular plant species, hotspots were distributed in lowlands and in areas with undisturbed habitat and volcanic landforms. However, because they are unique, it is important to assess hotspots for each stressor and habitat type independently. Moreover, we found a positive effect of survey effort for some habitat types; therefore, care must be taken to avoid survey bias among regions and habitat types.

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We developed a remote sensing method to identify forest areas of high conservation value, i.e., with high densities of large trees, in a spatially heterogeneous forest. The crown size index (CSI) was calculated by object-based image analysis using a high spatial resolution aerial photograph. The validity of this index was tested for a deciduous forest in Kuromatsunai, Hokkaido. The CSI had significant positive effects on the average diameter at breast height (DBH) and the average tree height of canopy layer trees measured at the ground truth. Forest areas of high CSI value were characterized by high dominance of Fagus crenata in the canopy layer and well-developed understory vegetation containing a higher diversity of forest-dwelling plant species, suggesting that this index is adequate for detecting forest areas of conservation priority.

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We investigated the overwintering habitats and host plants of S. rubrovittatus in order to determine methods to control this major insect pest in rice production without harming biodiversity. The study was conducted at 33 sampling plots within meadows and fallows (the primary sources habitats of the pest) in the Tajiri area of the city of Osaki, Miyagi prefecture, Japan, where pioneering organic rice farming has been extensively conducted. Adult S. rubrovittatus was abundant in unmowed meadows dominated by Lolium multiflorum in summer through late autumn. Echinochloa spp.. Digitaria sanguinalis, and Pennisetum alopecuroides (L.) Spreng also frequently grew in these meadows. Furthermore, each of these grass taxa supported relatively high hatching success of overwintering eggs for this insect: 85.7%, 42.1%, 21.7%, and 25% respectively. The density of adult S. rubrovittatus was also positively correlated with the abundance of hatching eggs. These results suggest that meadows dominated by Lolium multiflorum that are not intensively managed are very important overwintering habitats for S. rubrovittatus. Future studies should examine how and when to manage these habitats to contribute to pest management without the use of insecticides.

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The raccoon (Procyon lotor) was introduced from North America to Japan, where it escaped from captivity in the 1960s and spread to several locations. P. lotor has been reported to affect aquatic animal communities but information about its dietary habits in Japan is limited. Across its native range in North America, the raccoon's diet is broad and includes aquatic animals, mammals, grains, and fruits. We analyzed the intestinal contents of 113 raccoons trapped in Yokohama City, Kanagawa Prefecture, in eastern Japan. Fruits and seeds accounted for 〜50-75% of the gut contents, followed by mammal hair (10-15%), plant leaves (5-20%), and insects (2-10%). The content of aquatic animals in the intestines was limited, with observed frequency (%) and quantity (%) as follows: fish (3.0%, 0.2%), crustaceans (3.0%, 0.1%), and shells (3.4%, < 0.1%). Although the composition of intestinal contents does not directly reflect intake, it is unlikely that aquatic mammals were an important food source for raccoons in Yokohama. Food analyses like those conducted here are needed for monitoring the effects of raccoons on aquatic animal communities.

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Cypripedium macranthos Sw. var. speciosum (Rolfe) Koidz. (Orchidaceae) is a popular horticulture species that is threatened in the wild. The preservation of endangered plants in cultivation is important for maintaining the numbers of individuals and strains. However, there is a risk of genetic contamination or altering the historical genetic structure of the species. Therefore, the cultivation of endangered species requires careful management. To reveal the genetic variation in the cultivated population of C. macranthos var. speciosum in Iwate Prefecture, this study investigated the chloroplast trnL-F intergenic spacer and nuclear ribosomal internal transcribed spacer (ITS) sequences. This showed that one individual had a clearly different sequence from the others. This different sequence was identical to or very similar to those of the Chinese endemics C. yunnanense, C. franchetii, and C. calcicola. Therefore, this individual was suspected of not being a native Japanese species. Consequently, it is necessary to investigate the morphological and genetic characteristics of all of the other individuals in the population as soon as possible and develop a management plan based on the results.

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