[in Japanese]

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Worldwide, wetlands are faced with ongoing degradation and loss due to human activities. Nevertheless, there is insufficient knowledge of the area, current conditions, and changes in wetlands because most nations lack wetland inventories. This study established a wetland inventory for Hokkaido, which contains a large proportion of the wetland area in Japan. We determined their current status and distribution, the potential risk of degradation based on the Hokkaido Land Use Master Plan, and the conservation status of wetland legally. We identified 119 lowland and 61 highland wetlands in Hokkaido. Based on the Hokkaido Land Use Master Plan, 90.2% of the area of highland wetlands had environmentally friendly plans, whereas 27.5% of the area of lowland wetlands was planned for urbanisation or agricultural use. Of the highland wetlands, 96.2% were included in conservation areas under legal regulations versus 63.5% of the lowland wetlands. Accordingly, it was apparent that the main risk of wetland degradation in Hokkaido was in lowland areas. In order to conserve wetland in Hokkaido, it is necessary to consider legislating their protection, especially in lowlands, which are exposed to higher potential degradation risk.

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The harvest mouse Micromys minutus (Pallas, 1771) builds spherical nests of grass leaves about 1 m above the ground during its breeding season. However, its nesting behavior during winter remains largely unknown. We clarified the effects of winter vegetation on M. minutus winter nesting environments. During the winter of 2016, we surveyed overwintering nests in 19 grasslands that had been surveyed during the 2014 and 2015 breeding seasons, and recorded nest properties and environmental factors. We found 12 overwintering nests in nine grasslands. Vegetation cover positively affected wintering nests. The average height of overwintering nests was 28.92 ± 13.12 cm (mean ± standard deviation); winter nests were lower in height than summer nests. Summer nest heights were affected by total vegetation height. Overwintering nests were not affected by vegetation height; however, winter mowing negatively affected overwintering nests. In areas where many overwintering nests are found, plants 30 cm in height appear to be important for conservation of this species.

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We investigated the co-occurrence of two endangered freshwater pearl mussel species (Margaritifera laevis and M. togakushiensis) within 100-m reaches of rivers in Hokkaido, northern Japan, using DNA-based identification techniques to compare differences in PCR-amplified fragments of mtDNA. Mussel sampling was conducted in 53 rivers across 31 watersheds between May 2016 and October 2017, and co-occurring distributions were charted on a 10×10-km mesh map. We detected M. laevis in 39 rivers in 23 watersheds and M. togakushiensis in 40 rivers in 25 watersheds. The two species co-occurred in 26 rivers in 17 watersheds. The ratio of the number of study rivers where both species were found to the total number of study rivers in the region was highest in eastern Hokkaido (68%). In addition, the two species co-occurred in 19 out of a total of 38 study meshes, and the ratio of the number of study meshes where the species co-occurred to the total number of study meshes in the region was also highest in eastern Hokkaido (67%). Genetic analysis of tissue samples revealed areas with higher probabilities of co-occurrence of the two target species within the same reaches. We believe that these findings could provide important information for future studies and conservation planning for pearl mussels in Hokkaido.

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The diversity of carnivorous aquatic insects (Coleoptera; Hemiptera) is declining with changes in the rice paddy environment. Environmentally friendly farming methods that reduce the use of pesticides and herbicides are gaining attention as effective conservation methods. However, little is known about how environmental factors other than farming practices affect aquatic insect communities. Here, we investigated the effects of multiple factors on aquatic insect communities at the individual rice paddy and landscape levels. The results showed that the taxon richness of aquatic insects increased with prey abundance and water temperature, but decreased with conventional farming practices. The landscape between 2,000-3,000 m best explained the taxon richness and the abundance of aquatic insects. The ratio of water area excluding paddies (ponds, fallow paddies, and rivers) had a positive effect on the taxon richness of aquatic insects, whereas the proportion of rice paddies had a negative effect. We suggest that a stable prey supply and the management of water areas and forests are needed to conserve aquatic insects, in addition to promoting environmentally friendly farming.

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To monitor the reproductive status of an endangered Asian black bear population in Shikoku, we investigated the pedigree structure of 13 individuals that were captured between 2005 and 2017. Using 19 microsatellite markers for paternity testing, we identified four mother-offspring pairs and five father-offspring pairs. The results suggest that only a few males participated in reproduction. Pedigree analysis indicated that all of the reproductive males identified in this study were siblings. The allelic richness of the Shikoku bear population was lower than those of other local populations. The observed heterozygosity was significantly greater than the expected heterozygosity in the Shikoku population, suggesting a very small number of breeding individuals. The size of this population, based on pedigree data and estimated by the method of Creel and Rosenblatt, came to 16-24 individuals.

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We investigated the distributions of two native (Dolly Varden Salvelinus malma malma and whitespotted char Salvelinus leucomaenis leucomaenis) and one invasive (rainbow trout Oncorhynchus mykiss) salmonid species using environmental DNA (eDNA) analysis in the centre of Hokkaido Island, Japan. The native species' populations are fragmented by damming and threatened by invasive species. Therefore, DNA real-time PCR assays specific to these three salmonids were used to investigate the effects of damming and invasive species on the two native salmonids. Salvelinus malma populations exhibited separation due to damming. Additionally, they were not eliminated by invasive O. mykiss but rather lived together at some sites. Salvelinus leucomaenis populations occupied the lower reaches more than did S. malma populations. We detected S. leucomaenis and the invasive O. mykiss population less frequently than expected. We were unable to clarify the seasonal movements of species, even during their reproductive phase, despite conducting eDNA surveys throughout the year, including during the coldest parts of winter. We hypothesise that damming may function both as a protective barrier against invasive species and as an impassable barrier preventing migration; however, the significance of these potential functions was not revealed in this study. From a long-term perspective, fragmentation may negatively affect the viability of native Salvelinus populations. Conservation efforts for native Salvelinus species would be aided by additional studies using eDNA surveys, which can be effectively conducted even in mid-winter.

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To determine the distribution of the Oki salamander (Hynobius okiensis) on Dogo, in the Oki Islands, we evaluated the seasonal variation in the larval population in a field survey and performed predation experiments with two potential predators. We conducted larva collection surveys at two sites each in four catchment areas from April to September in 2016. Overwintering larvae and the year larvae were sympatric from May until August. Subsequently, only the year larvae appeared in September. At the sites inhabited by demersal fish species (e.g., gobies), salamander larvae were seldom seen. The predation experiments revealed that the year larvae are at high predation risk not only from demersal fish but also from overwintering larvae, suggesting that cannibalism occurs in nature. We speculate that newly emerged H. okiensis larvae hatched and joined the overwintering population in the period from April to May and the overwintering larvae metamorphose and land in August. The presence of demersal fish in microhabitats overlapping those of H. okiensis larvae is likely to be related to the distribution of H. okiensis in the field.

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The Aichi Biodiversity Targets (ABTs) of the Convention on Biological Diversity (CBD) define world targets for the conservation and sustainable use of biodiversity from 2011 through 2020. Post-2020 targets (post-ABTs) will be determined at the 15th Meeting of the Conference of Parties to the Convention (CBD-COP15) in 2020, and many studies on the challenges presented by these targets, and their effectiveness, have been conducted worldwide. In this article, we review possible approaches to be considered when setting these follow-up targets, such as specific, measurable, ambitious, realistic, time-bound (SMART) targets. Then, by focusing on Aichi Target 11 for protected areas as a case study, we discuss the challenges and concepts that could be incorporated into the new post-2020 targets, together with radical suggestions for modifying the current targets, using detailed examples in Japan. Lastly, we suggest that while nature preservation should be developed, other, approaches to nature, such as ecosystem-based disaster risk reduction, should also be implemented.

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Approximately 75% of current emerging infectious diseases are believed to be zoonotic. To address concerns, we reviewed recent wildlife management studies and systems in Japan and abroad that included countermeasures for tick-borne diseases, such as severe fever with thrombocytopenia syndrome (SFTS), which has been spreading in western Japan. Many non-host-specific ticks get pathogens from wild animals and transmit diseases to humans via the tick salivary gland. Foreign studies suggest that host species diversity reduces the infection risk due to the dilution effect. However, multiple factors can affect zoonotic diseases, including climate change, urbanisation, and life-style changes. To deal with these diseases, interdisciplinary and cross-cutting programs, such as One Health, have been implemented, although relevant wildlife management has not necessarily been developed. Further actions based on scientific knowledge and cooperation involving multiple sectors are necessary.

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Thematic mapping is an effective tool for the management of alien species. The spatial scale of this thematic mapping is a key issue because maps at different scales can serve different purposes. Large-scale maps are useful for policy planning, such as eradication or mitigation, whereas small-scale maps are useful for the implementation of management strategies. In this case study we established a thematic map for management of Rudbeckia laciniata L. in the town of Kokonoe, covering a part of Kujyu-Aso National Park. On a large scale, we divided the current distribution range of this species into zones for eradication, suppression of expansion, and monitoring. On a smaller scale, we set priorities for eradication work on many R. laciniata populations in the eradication zone. A comprehensive management plan, i.e., a thematic map, should contain these multi-scale maps. We have organised a series of such mapping procedures for conducting effective management by citizen volunteers, municipal government, and the national park office.

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Issues related to biodiversity now attract much attention, not only from biologists but also from the wider public. Biodiversity has been recognized to play an important role in a number of social issues, such as disaster prevention and mitigation, social and economic capital and the sustainable use of natural resources. Consequently, scientists working in the field of biodiversity have been increasingly required to contribute to relevant policy-making processes. In reality, however, scientific research is not being used effectively in policies and practices, in a phenomenon widely known as the research-implementation gap in conservation science. One important and practical way for scientists to contribute to solving social issues is through conducting and publishing research with the potential to provide the scientific knowledge required to solve those issues. However, it is not easy for many scientists to identify social issues that urgently require scientific knowledge, or to provide the required knowledge at the right time. Attempts to facilitate this process could contribute to bridging the research-implementation gap. Here we first introduce legislative scans conducted annually by the British Ecological Society (BES) as a specific example of such attempts, and illustrate how the BES reviews and widely publicizes forthcoming legislation and expected policy developments that are likely to have consequences for the environment as well as for ecologists and conservation scientists. Second, as a preliminary attempt in Japan, we also try to provide an overview of biodiversity-related international and domestic policies since 2015, specifically covering the following five topics: the Convention on Biological Diversity (CBD), the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), climate change adaptation, green infrastructure, and wildlife-human conflicts. Finally, we discuss the importance of proactive approaches in Japanese scientific communities, for example through the implementation of legislative scans, to bridging the research-implementation gap in biodiversity-related issues.

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