In the subtropical prefecture of Okinawa, many alien tropical flowers and fruits have been planted along roadways or in gardens. However, the impacts of such planted trees on native pollination and seed dispersal networks are poorly known. In the present study, we investigated diurnal patterns of nectar secretion and pollinator visits to flowers on coral trees (Erythrina variegata L.). Although the coral tree is known as a diurnal bird-pollinated plant, several taxa of pollinators, such as birds, insects, and flying foxes were observed on the flowers of planted coral trees on Okinawa-jima Island. Flowers began to open in the morning, and nectar was only secreted during the daytime. In 60% of all flowers, almost all nectar was harvested by diurnal flower visitors, such as white eyes (Zosterops japonicas [Temminck & Schlegel]), by evening. The remaining nectar of unharvested flowers (30% of total flowers) was depleted by nocturnal Ryukyu flying foxes (Pteropus dasymallus Temminck) during the nighttime. Although planted coral trees provide food resources for the endangered Ryukyu flying fox in urbanized areas, these planted trees may rob native plant species of opportunities for pollination or seed dispersal. In Okinawa, which harbors many vertebrate-pollinated plants, the networks between plants and flying foxes/birds must be considered when selecting trees to plant along roadways or in green spaces.

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To clarify the impacts that increasing populations of Sika deer are having on bird communities, we examined data on the community structure of birds in the Oku-Nikko area in Tochigi Prefecture that were collected during breeding seasons between 1977 and 2009. The bird community data were collected during 10 separate periods: 1977, 1978, 1979, 1991, 1992, 1993, 1998, 2003, 2008, and 2009. These data included years before the early 1980s, when the Sika deer population began to increase. Bird community structure differed significantly between years before 1993 and years after 1998. Additionally, after 1998, a high relative abundance of tree-hole nesting, canopy nesting, bark foraging and fly-catching bird species was observed. Conversely, birds that preferred nesting and foraging in understory vegetation and brood-parasitic birds were rarely observed after 1998. The impact of the increased Sika deer population on forest vegetation in Oku-Nikko became significant after the late 1990s. It is conceivable that the observed changes in bird community structure that began in 1998 were mainly caused by alterations in the vegetation community because of the increased population of Sika deer.

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I investigated populations of the forest green treefrog Rhacophorus arboreus in relation to changes in its habitat at Kanazawa Castle (Ishikawa Prefecture, Japan) during the period 1984-2012. There were no marked population fluctuations from the 1980s through the mid 1990s, but frog numbers declined rapidly around the turn of the millenium. Population numbers increased again in the middle of the first decade of the new century, and frog densities have been high since about 2010. Although the locations of the ponds that served as breeding sites for this species shifted, because of changes in land-use in the late 1990s, there were always a number of different breeding sites available to the frogs. I did not identify the predominant factors associated with population size variability, but environmental changes in breeding sites probably played a part. Conservation of multiple breeding sites within the habitat range of the forest green treefrog is, therefore, considered important for the protection of this species. Exclusion of alien predators from breeding sites and provision of barrier-free routes between breeding sites are also considered crucial for conservation.

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To overview Satoyama biodiversity in Japan, we classified and mapped national land use into the categories "wilderness land use," "rural land use," "plantation," and "urban land use" using a high-resolution (50-m grid) land-use map. We also mapped the modified Satoyama index (M-SI), defined as the Simpson's diversity index of land-use types within a 6-km square weighted by the proportion of agricultural land use, for every rural land-use cell. National and quasi-national parks were shown to include not only higher proportions of wilderness land-use cells than areas outside parks but also significantly more rural land-use cells with high M-SI (≥0.5) than expected. However, parks along the Sanriku shoreline, which were affected by the Tohoku catastrophe and are planned for inclusion in national parks, were shown to be occupied by high numbers of plantations. Current world natural heritage sites in Japan, except for the Ogasawara Islands, were shown to include relatively few rural land-use cells, although cells with high M-SI were widely distributed in the Amami Islands, one of the candidate areas for new world natural heritage sites. From these results, we concluded that Satoyama conservation management in national parks can contribute greatly to biodiversity conservation in Japan.

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Although biodiversity monitoring by citizen scientists has great potential for biodiversity conservation, several problems are associated with this method: e.g., a lack of scientific and taxonomic knowledge of the target species group and/or difficulty arranging such activities. In the present study, we attempted to establish a canonical protocol for biodiversity monitoring by citizen scientists using standard mobile phones, which are very common throughout Japan at the present time. First, we constructed a web system that can project the digital photos taken with the mobile phone and sent via standard e-mail, onto Google Maps. Subsequently, we conducted a series of pilot campaigns for biodiversity monitoring at four sites in Japan in collaboration with regional curators and teachers. Finally, we published the records of all campaigns on our project website. Using this procedure, we believe that three essential points of success in biodiversity monitoring by citizen scientists have been satisfied: 1) providing an easy-to-use tool, 2) collaboration between citizen scientists and researchers, and 3) providing rewards for the citizen scientists. Establishing such monitoring protocols has important implications for biodiversity monitoring conducted by an entire nation.

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We investigated the vascular plant species composition and underlying factors for paddy dike vegetation in a small river basin in the southernmost part of Iwate Prefecture, Japan, where traditional terraced paddy fields remain. In total, 455 vascular plant species, including 41 naturalized and 14 endangered species, were recorded from 92 dikes (13,784.2 m^2). Indigenous herbaceous species found in these dikes could be classified into wetland (36.0%), grassland (40.3%), and forest (23.7%) species with different habitat requirements. Generalized linear mixed models revealed that the most important factor affecting floristic composition in a paddy dike was the land-use type of adjacent areas. Considering the distributions of wetland and endangered species, we concluded that paddy dikes satisfying the following conditions had the highest conservation priority: (i) directly bordering traditional irrigation ponds or ditches; and (ii) larger and steeper, and located in terraced paddy fields.

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Recognizing rare and endangered species and seeking their preservation is today the primary approach in conserving biological diversity. Although such efforts have achieved significant gains, there are undeniable limitations to this species-based approach. Here, we introduce the concept of "endangered ecosystems" (i.e., endangered spaces), which promotes the conservation of whole ecosystems and, thereby, the organisms that are inseparable from them. This ecosystem approach is important as a basis for conserving nature in a comprehensive way. An increasing number of conservation projects apply this concept in practice. In reviewing 22 examples from the red lists of ecosystems, landforms, and communities, we found 10 major features of endangered ecosystems: decreasing in area; intrinsically rare; declining ecological processes and function; associated with significant fragmentation; facing major threats from development; having high species diversity; providing good habitat for rare and endangered species; having a large, intact wilderness area; representative of a geographic region; and having high cultural and aesthetic values. The concept of endangered ecosystems is expected to overcome the limitations of the species-by-species conservation approach. In addition, it would assist in the preservation of ecosystems that lack protection from traditional legislative means; promote scientific research into ecological processes and functions; and motivate engagement among land managers, researchers, and public stakeholders to accelerate conservation planning in geographic regions.

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We explored the current status of sexual reproduction and clonal growth in six populations of the common reed, Phragmites australis, in eastern parts of Shiga Prefecture and Mizoroga-ike pond in Kyoto Prefecture. At each population, we determined genets using six SSR markers and investigated seed set and ploidy levels. Genet diversity was high in four populations, three of which also had high seed set. In contrast, two other populations were composed of a single genet and had very low seed set. Similarly low genetic diversity and seed set has been previously reported for some large populations surrounding Lake Biwa and Naiko. We germinated seedlings to determine ploidy levels for the populations and found tetraploid, hexaploid, and octaploid individuals. Hexaploid individuals may be a result of mating between individuals of different ploidy levels. We found no seedlings, even in populations composed of several genets, suggesting inappropriate environmental conditions for seedlings, such as flooding, high water levels and lack of open patches. This suggests that these populations are maintained by prolonged clonal growth, not by the recruitment and establishment of seeds.

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Using database and activity records from a participatory program for controlling and monitoring an invasive alien species, Bombus terrestris, we evaluated the roles of participants who continued the activity for more than 1 year (hereafter, "experienced participants") and the effects of several means of information transmission from researchers to public participants. The number of experienced participants steadily increased during 2006-2011. The proportion of B. terrestris (total of queens, workers, and males) captured by experienced participants was 85.5 ± 8.9% (mean ± standard deviation) during the years 2007-2011. Generalized linear mixed models (GLMMs) revealed that the number of years of participants' experience significantly positively affected the number of spring queens that they captured. The present study suggests that experienced participants play important roles not only in effective collecting but also in recruiting new monitors, as 28 of 49 new participants (57.1%) conducted their monitoring together with experienced participants in 2011, when such data analysis was possible. The proportion of new participants for a given year who continued the activity in the subsequent year was significantly higher for participants who attended guidance courses or other types of meetings or events than for those who did not attend such training, suggesting the importance of face-to-face information transmission in acquiring experienced participants.

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Warm-temperate evergreen broad-leaved forest (WEBF) (lucidophyllus forest) is endangered ecosystem in Japan, due to anthropogenic impacts, transformation to commercial forests, and poaching. Potential vegetation coverage in Japan is ca. 50% of the land, however primary WEBF is only remained ca.1.6% of the land. The habitats fragmented only into ridge, steep slope and sacred sites of temple and shrine in western parts of Japan. WEBF is characterized by high species richness such as co-dominants of Fagaceae, Lauraceae, and Theaceae. In 2005, the agreement on the "Conservation and Restoration Plan for the Lucidophyllous Forest Zone of the Aya River Basin [so-called "Aya Lucidophyllous Forest Project (Aya Project)] " was signed among the Kyushu Regional Forest Office, Miyazaki Prefecture, Aya Town, the Nature Conservation Society of Japan (NACS-J) (Public Interest Incorporated Foundation, NGO) and Teruha Forest Association (citizen group). Furthermore, the area is registered by UNESCO as Aya Biosphere Reserve (AyaBR), which is consisted of core (682ha), buffer (8,982) and transition (4,916) in July, 2012. Our final goals of Aya project aim to conserve and restore endangered forest ecosystem, implementation of sustainable development and promotion of local community in harmony with nature, and enhancement of environmental education through bottom up approach.

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Rhodeus atremius, an endemic bitterling fish from Japan, comprises two endangered subspecies: R. a. atremius and R. a. suigensis. The latter subspecies, designated as a Nationally Endangered Species of Wild Fauna and Flora by the Ministry of Environment of Japan, is noted for drastic declines and the extinction of local populations through habitat deterioration. Despite their strong phenotypic resemblance, these two subspecies are much diverged in DNA, each forming a distinct evolutionary lineage. Nevertheless, these two subspecies were clumped into a single subspecies, R. smithii smithii, in a newly published fish encyclopedia, which will lead to R. a. suigensis being dropped from the list of Nationally Endangered Species. This paper critically reviews the validity of this new taxonomic arrangement of R. atremius, including R. a. suigensis, based on phylogenetic systematics. Its potential risk against the conservation management of R. a. suigensis is specifically discussed.

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