To manage the expansion of bamboo forests efficiently, it is necessary to predict where expansion is likely. However, predicting bamboo distribution using statistical models is challenging due to biased distributions, heterogeneous invasion histories, and strong neighbor effects. Furthermore, clonal and invasive species such as bamboo show a non-linear response to environmental factors. Here, we construct a spatial model to predict locations of high penetration probability after controlling for these problems, using data for bamboo distribution in Toyooka, Hyogo Prefecture, Japan. First, we used MaxEnt to reveal the full range of possible bamboo survival and to control for the effects of clonal growth. Second, we constructed a predictive model of invasion using environmental factors. The first model showed that distance from the source patch strongly affected expansion and that constraints from environmental factors were not significant. The final model explained about 70% of actual expansion. Scenario analyses showed that bamboo expansion is best controlled by removing smaller patches. Based on our results, we discuss issues in bamboo forest management and planning.

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We assessed the effects of predation by four alien frogs in Hokkaido, Japan, by examining their diet composition based on an index with broad utility in studies of anuran food habits. Bufo japonicus formosus and Glandirana rugosa preyed on various above-ground insects, while B. japonicus formosus, Pelophylax nigromaculatus, and P. porosus preyed on frogs. Therefore, the potential impacts of invasion and competition on both native frogs and the unique ecological pyramid of Hokkaido are of concern. We found that three of the alien frogs preyed on rare species, while one preyed on other introduced species such as Bombus terrestris. The distributions of Bufo japonicus formosus, P. nigromaculatus, and P. porosus have increased, raising concerns about the impacts on their prey. P. nigromaculatus and P. porosus, which inhabit paddy fields, might also have major impacts on local wetland ecosystems.

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In the present study, we conducted a vegetation survey in Phragmites australis (Cav.) Trin. ex Steud. communities in Myoginohana Marsh, Ibaraki Prefecture. Depending on the type of bryophyte species occurring within the P. australis community, clear differences were found in the species composition and habitat of vascular plants. Phragmites australis communities could be divided into four community types based on the identity of the moss: Sphagnum fimbriatum type (P. australis community with S. fimbriatum Wilson), Sphagnum microporum type (P. australis community with S. microporum Warnst. ex Cardot), Sasaokaea type (P. australis community with S. aomoriensis (Paris) Kanda), and a no-moss type (P. australis community with no moss). The number of vascular plants present in P. australis communities where S. fimbriatum, S. microporum, or S. aomoriensis was also present was significantly higher than that observed for P. australis communities where bryophyte species were absent. Similarly, P. australis communities in the presence of S. fimbriatum, S. microporum, or S. aomoriensis experienced better light conditions and exhibited significantly less P. australis coverage and lower vegetation height compared to those without bryophyte species. Rare species occurred in the S. microporum and S. fimbriatum types of P. australis communities. Therefore, we concluded that the presence of S. fimbriatum, S. aomoriensis, or S. microporum is an important indicator of the environmental conditions in P. australis communities.

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Marxan is reserve selection software that was developed to identify efficient, near-optimal spatial solutions to conservation planning. Here we describe its basic mechanisms and introduce previous studies to outline the program's use and potential applications. Marxan seeks sets of planning units to achieve a given conservation goal at minimum cost based on the principle of complementarity. It uses a wide array of conservation targets, including genetic diversity and habitat types as surrogates, in addition to species. We introduce previous studies focused on reserve selection under future climate or land-use change and on evaluating priority areas by considering trade-offs between biodiversity conservation and ecosystem services. We also review research on priority areas for the reintroduction, restoration, and management of invasive species. Marxan depends on user-specified ecological and socioeconomic parameters and, therefore, may be subject to bias. Nevertheless, Marxan can suggest spatially explicit solutions based on conservation targets and given costs, facilitating the effective investment of monetary or human resources and aiding consensus among stakeholders and decision makers.

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To examine the habitat and breeding season of striated spined loaches, we conducted field surveys on the northwest coast of Lake Biwa. Mature adult fish (42-107 mm in SL) immigrated into the Mizusumashi rice field artificial swamp from April to July, generally after heavy rains. Juveniles were captured from June to July. We found that almost all adult fish appeared from April to June, and no juveniles were captured in the emergent vegetated areas on the lake shore and in an irrigation ditch. Our results of adult body size distribution suggest that Cobitis minamorii oumiensis Nakajima and C. magnostriata Nakajima reproduce at the Mizusumashi rice field. We also show that reproduction is triggered by heavy rainfall, and that it mainly occurs in the artificial swamp in our study area.

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The freshwater mussel, Cristaria plicata, is endangered in Tottori prefecture, and information on the population structure and reproduction of the species is necessary for conservation purposes. In the present study, the size structure of mussels, the presence of larval glochidia in females, fish fauna in mussel habitat, and the host suitability of their larvae were investigated in three remaining populations. Mussel size distribution in Tanegaike Pond was biased strongly toward larger individuals, indicating a lack of recruitment in this population in recent years. Although glochidia were observed in females during the reproductive season, the invasive predatory fishes Micropterus salmoides and Lepomis macrochirus were dominant in the pond, and predation on larval hosts by these invasive species is suggested to be a major factor inhibiting recruitment. In contrast, in other two ponds, smaller individuals were found together with larger animals. Invasive predatory fishes were not observed in these ponds, and the larval host Carassius spp. was dominant, indicating that these ponds were suitable for C. plicata recruits. These results suggest that the population dynamics of C. plicata strongly depend on fish communities and that the freshwater mussel population in Tanegaike Pond is endangered because of the dominance of invasive predatory fishes. We propose some future directions for the conservation of C. plicata populations in the Prefecture.

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Habitats, flowering characters and information of escape from cultivation were studied by investigating the populations in the field, observing plants under cultivation, examining herbarium specimens, hearing investigation and literature survey. Genetic diversity of Nymphoides peltata was re-examined by SSR polymorphism. Though the analysis of genetic diversity was not successful because some loci were difficult to identify, genetic polymorphism was found within the population of Lake Inawashiro and Lake Biwa, respectively. Non-flowering populations were found to grow scattered in Japan and have genetic polymorphism. The most populations of N. peltata in Lake Biwa were recorded from the attached small ponds and connected drains or rivers. Escaping populations were revealed to scatter various places.

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Many alien organisms (plant competitors, herbivorous animals, and host-specific parasites) are hazardous to endangered plants and important plant communities requiring conservation. Therefore, estimations of such hazards based on the biological traits of alien organisms are necessary; however, such information is not yet readily available. Despite technological deficits, we must immediately evaluate the hazards posed by alien organisms to plan countermeasures. Using paired comparisons based on questionnaires answered by specialists, we developed a method to evaluate the hazards of alien organisms that can damage native plants and communities. The knowledge of specific specialists was often limited to certain habitats (e.g., forest or wetland) and climatic zones (e.g., subtropical or boreal). Therefore, we constructed a table of paired comparisons using the answers from all specialists. Due to difficulties comparing the hazards of various alien species in diverse habitats, we first compared the importance of habitat (necessity of countermeasures) and then compared the hazard posed by individual alien species in each habitat. Hazards to native plant species through reproductive interference, hybridization, or host-specific parasitism were evaluated separately. Among habitats, vegetation on oceanic islands was the most important habitat in terms of hazards posed by alien species. Plant communities in aquatic systems and on oligotrophic sand and gravel along riversides were next most important.

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Cerasus speciosa (Koidz.) H. Ohba, a deciduous broad-leaved tree, is native to the Izu Islands of Japan, and has now been reported from many coastal forests in the Tohoku region. However, C. speciosa was not mentioned in four articles dealing with coastal forests of the Sendai Gulf featured in Volume 19, Issue 2 of this journal (Disturbance and recovery of the coastal-ecotone vegetation following the Great East Japan Earthquake and Tsunami). We suspect that inaccurate species identification, and not the actual absence of C. speciosa, is to blame, and hope that future research on coastal forests of the Sendai Gulf will remedy this.

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The 10th meeting of the Conference of Parties to the Convention on Biological Diversity (CBD-COP10), which was most successful COP among the history of international environmental treaties, adopted over 40 decisions including Strategic Plan of Biodiversity 2011 to 2020 and 20 Aichi Biodiversity Targets. And based on recommendation from one of CBD-COP10 decision, 65 session of United Nations General Assembly declared 2011 to 2020 as United Nations Decade of Biodiversity. Parties to the CBD gathered per two year and its twelfth meeting (COP12) was held in 2014. On the occasion of COP12, secretariat of the CBD with scientific advisor launched 4th edition of the Global Biodiversity Outlook (GBO4) and reviewed the progress of strategic plan of biodiversity and Aichi Biodiversity Target. This report briefly introduce the outcome of GBO4 and decision made by COP12 as a response to the outcome of GBO4.

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