The number and species of small mammals that drown after falling into road-side gutters (45 cm in width and 45 cm in depth) with flowing water (10–25 cm in water depth and 1.3–1.6 m/s in velocity) were investigated. A field survey was conducted along an approximately 1.5 km stretch of gutters in Fujinomiya, Shizuoka Prefecture in Japan from June 2001 to September 2004. Data were collected from 132 observations (days). A total of 152 drowning animals, consisting of 13 small mammal species, were collected, including the nearly threatened mole, Euroscaptor mizura. Drowning animals comprised 81 percent of the species of small mammals in the study area. The average frequency of drowning was 1.16 animals per day. Microtus montebelli drowned mostly around pasture areas, which is probably due to habitat differences around gutters. Drowning of small mammals in side gutters occurred between March and November, while no drowned animals were observed between December and February. The seasonality of occurrence could be related to the breeding season of small mammals. Our study demonstrated that side gutters without cover were lethal for small mammals, and thus, it is necessary to take preventive measures when constructing side gutters.

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To reveal behavioral characteristics of damage-causing wild boar individuals (Sus scrofa), we investigated seasonal and daily changes of habitat selection for individuals captured near a forest’s edge. Six wild boars were captured during May–November in 2004 and 2005. Their preferences related to vegetational and topographical factors were analyzed using a generalized linear mixed model (GLMM). Interindividual differences in utilization of areas outside of the forest were also assessed. Results showed that one individual never exited the forest (inner individual). Most wild boars which used areas out of the forest (outer individuals) intensively preferred the forest edge. In contrast, the inner individual used a wide area from the forest edge to more than 1,000 m from the forest edge. From the viewpoint of seasonal and diurnal variation, outer individuals selected woodland vegetation and low elevation areas during the daytime. During the nighttime they preferred areas outside of the forest and low elevation areas. Results suggest that nuisance control for reducing crop damage should be conducted around the forest edge because outer individuals intensively use these areas.

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Asiatic black bears (Ursus thibetanus) in Kyoto Prefecture are recognized to consist of two populations separated by the lower stream of the Yura River; the population on the east side of the river is named the Tanba population, and the population on the west side of the river is named the Tango population. More young males in the Tanba population were killed for being nuisances than in the Tango population. We examined the relationships between such characteristic of sex-age composition of the bears killed and possibly relevant factors including the method, reason, month, and landscape of capture, as well as the distribution of mature females. The locations where male bears were killed suggested that in the mating season, mature males tended to move into areas where mature females were most likely to be found. However, no difference was found between the age of males killed within the area of mature females and those killed outside of that area. Rather, captures in forest areas appeared to result in more young males killed. The fact that more young males in the Tanba population were killed than in the Tango population might be due to the fact that the nuisance kills in Tanba were mainly in forest areas to control bears causing tree damage, while nuisance kills in Tango were mainly in non-forest areas to control bears that invaded human settlements and agricultural areas. However, the possibility remains that the composition of killed bears reflected the actual difference in the composition of the two populations in the wild.

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Connective tissue cores (CTCs) of the lingual papillae of the lesser mouse deer Tragulus javanicus were examined by scanning electron microscopy (SEM) and compared to those of other animals. The CTCs of the filiform papillae of the lesser mouse deer were structurally similar to those of the mountain goat Oreamnos americanus. The CTC of the long flat central papilla of the vallate papilla was covered with numerous small spines. The CTC of the foliate papillae appeared as ridges and grooves. An important finding was the presence of distinct and prominent foliate papillae on the posterolateral sides of the tongue.

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The agaric mushroom Hebeloma radicosum grows specifically on mole latrines near the animal’s nest. Consequently, its fructification enables one to locate mole nest. Three cases of fructification in Kutsuki, Takashima-shi, Shiga Pref., were found to have taken place on the nests of the Japanese mountain mole, Euroscaptor mizura. These cases were located at 770 m, 440 m, and 260 m in altitude. The nests were vacant when collected and hence identified by assessment of tunnel size and hair characteristics. Furthermore, in the case of the nest at 260 m, the E. mizura mole using the nest was captured, which confirmed nest identification and provided direct evidence of the species in the area. The existence of E. mizura in northwestern Shiga and its nesting at such a low altitude are reported for the first time.

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We planned this feature hoping to contribute to the progress of the SWCPM for bear populations and related research in Japan. This feature is a proceedings of three bear research-related workshops held at the Annual Meeting of the Mammalogical Society of Japan in 2007. It contains 11 articles on the SWCPM implementation and other issues for bear populations in Japan, also including density estimation using hair-snare techniques, which is hoped to be an effective method for population monitoring, and two articles of critical commentary.

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We conducted a hearing focused on brown bear (Ursus arctos) and Asian black bear (Ursus thibetanus) population management policy in the 35 prefectural governments where bear species occur, to highlight the issues facing population monitoring and management, from July to September 2007. Eleven prefectures have carried out bear population management under the Specified Wildlife Conservation and Management Plans (SWCMP), which is a system under the Wildlife Protection and Hunting Regulation Law, and five prefectures have carried out management plans under their own intentions. Twelve prefectures did not have any written plans or guidelines for bear population management. While nine prefectures out of 24 that had no legal plan were planning to formulate legal management plans for their bear populations, the remaining 15 prefectures have no plan to establish any legal management plan. The current major management goals including legal and non-legal management plans were 1) avoiding the extinction of local bear populations, 2) avoiding human injuries by bears, and 3) reducing economic damage by bears. The most common subject of numerical goals in the plan was the upper limit of kills, which was listed by eight prefectures out of ten carrying out management plans with numerical goals. The major monitoring subjects were investigations of killed individuals, appearance and damage, acorn and nut production, and so forth. Major subjects in management operation were population management, conflict prevention, release of problem individuals, habitat securing, and diffusion and the widespread education of the public regarding bear conservation. Only three prefectures established an inter-prefectural coordinated management plan for the black bear population, and that was in the Western-Chugoku Region. The placement of numerical goals regarding conflict occurrence and monitoring, the establishment of population trend monitoring measures, and the establishment of monitoring systems by local populations are essential to improve scientific population management of bears in Japan.

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Specified Wildlife Conservation and Management Plans for the Asiatic black bear, Ursus thibetanus, in the western Chugoku Mountains, Japan, were executed in 2002 and several investigations were carried out in Hiroshima, Shimane, and Yamaguchi Prefectures. Bear population sizes estimated by the mark-recapture method were 480 in 1999 and 520 in 2005. The number of bears killed as nuisances has increased since the 1960s, especially in 2004 and 2006, when unusually high number of bears intruded into residential areas (239 individuals were killed in 2004 and 205 individuals in 2006). Proportionately more older bears were captured in 2000–2006 than in 1996–1999, with no remarkable change in the sex ratio. Both the number of bears killed and the ratio of releases of captured bears differed among the regions. Differences in understanding of bear conservation and biology by local inhabitants and governments could be a reason of this. Although the recapture ratio of released bears was low, it was not clear whether these bears had learnt to avoid croplands. To conserve the bear population in this area more strictly, it is necessary to continue monitoring the population, to decrease the number of bears killed owing to accidental captures by traps for wild boars, and to promote public education on the conservation of wildlife.

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We reported on the current status and issues involved in the Specified Wildlife Conservation and Management Plans (SWCMP) for the Japanese black bear (Ursus thibetanus) in 2003–2007 in Hyogo Prefecture, Japan. Two populations of black bear in Hyogo Prefecture are distributed in the east-Chugoku and north-Kinki regions, and each of these populations has been isolated and endangered. However, the numbers of human-bear conflicts in these regions have been increasing. After the SWCMP was implemented, 86% of all bears captured for nuisance control and miss-trapping have been released with aversive conditioning. We fitted 44 bears with transmitters and monitored their subsequent behavior as long as possible. By such careful monitoring, we could avoid unneeded control-killing of bears. And we could euthanize bears in case of aversive-conditioning when captured again in the same or different village according to the guidelines of the SWCMP. These releases may have prevented the local extinction of the bear populations. We still have at least two problems related to bear management. First, we must develop more effective methods to drive away bears, release with aversive conditioning, and educate local people. Another issue to be solved is large scale management of bear populations distributed over multiple prefectures.

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Conflicts between humans and Asiatic black bears (Ursus thibetanus), largely inhabiting Nagano Prefecture, have been increasing recently. The Nagano Prefectural Government drew up a black bear management plan in 1995 and has implemented black bear management actions based on the plan. The plan was promoted to Specified Wildlife Conservation and Management Plan status at its revision in 2002. The Nagano Prefectural Government estimated its bear population size three times, first for the plan in 1995, and then for each of its subsequent revisions in 2002 and 2007. The direct count method was adopted in the former two estimations, while the hair trap method was adopted in the last estimation. The estimated population sizes were 1,362, 1,325–2,496, and 1,861–3,666 in 1995, 2002 and 2007 respectively. An upper limit of 150 annual kills was established in the hopes of stabilizing the bear population at 1,300 individuals, the level in the former two versions of the plan, whereas no fixed number was established in the most recent plan because of the low reliability of the estimated population size. The most necessary course is to develop simple and easy population trend monitoring methods rather than accurate population size estimation for black bear population management in Japan.

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We reviewed the implementation of the Specified Wildlife Conservation and Management Plans (SWCMP) for the Asiatic black bear (Ursus thibetanus) in Iwate prefecture and discussed its issues and future strategy. Asiatic black bears inhabit almost all regions of Iwate Prefecture, and the population is a large part of the overall black bear population in Japan. Nuisance kills have gradually increased since the 1980’s because of increasing agricultural damage and human injuries. Accordingly, the prefecture made a SWCMP for the Asiatic black bear in 2003 with the aim of coexistence between humans and bears. Monitoring subjects of the plan are the investigation of killed bears including biological traits, agricultural damage and human injuries, home range surveys with radio telemetry, acorn and beechnut production, and population trend and size. As for the problem of monitoring subjects, it was difficult to estimate accurate bear population size and previous population size was possibly underestimated. A monitoring system focused on neighboring prefectures with respect to each local population is needed. Recently, many bears have been wandering into human communities. We appreciate an approach that calls on the local community to prevent conflicts, such as weeding the areas surrounding the village and/or proper disposal of fruit waste.

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Monitoring programs concerned with a brown bear management plan devised for the Oshima Peninsula were surveyed and problems were reported. To get feedback about the management plan, trends in bear population and frequency of damage caused by bears have been monitored. Hunting statistics, biological analysis of captured individuals, distribution surveys via questionnaires and wide-area trace surveys have been carried out as a part of investigations of bear population trends for the whole of Hokkaido Island. And trials of population estimation via radio telemetry and hair-snagging were performed for a narrow region of the Oshima Peninsula. Although a rough estimate of this local population and examination for the establishment of a popula­tion estimate technique were performed, both lack of budget and staff shortage impaired the improvement of precision and development to a wider area. On the other hand, to monitor the frequency of damage, some new methods were tried, including the classification of problem bears by stage and estimation of the number of the problem bears. These should provide important indices to evaluate the progress of the management plan.

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Population estimates for bears (Ursidae), by a combination of noninvasive genetic sampling using hair-snares and capture-mark-recapture methods using DNA individual identification, are widely used in the world. In several areas of Japan, attempts have been undertaken to apply these noninvasive techniques. Compared with conventional methods, noninvasive methods have several advantages: 1) live-trapping of bears is unnecessary, 2) sampling is less biased than that of live-trapping, 3) sampling can cover larger geographical areas than traditional capture-mark-recapture sampling, and 4) genetic tags are permanent. However, we have to understand the structure of the methods and solve many issues before we apply this method, in order to estimate an accurate population size. In this paper, we describe procedures for these methods, including trap structures, study site selection, trap placement, hair sampling, individual identification by DNA analysis, and capture-mark-recapture models to estimate population size, and described points to notice.

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It is urgent to establish practicable methods for estimating bear population size for the management and conservation of two species of bear (Ursus arctos and U. thibetanus) in Japan. Noninvasive sampling techniques and DNA-based capture-mark-recapture methods have drawn attention as population estimate measures because these methods can be more efficient and less biased than the traditional capture-mark-recapture methods with live-trapping. These methods have become increasingly common and have proven to be powerful means for estimating bear population size in many countries. However, in Japan, the methods have not been adopted effectively due to some open problems. To consider the effective application of these methods, we scrutinized previous studies conducted in Japan and other countries and reviewed problems in three processes: sampling, genotyping, and population estimation. We suggest that well-designed planning by the ecologist, geneticist and mathematical modeling specialist is most vital to the success of DNA-based capture-mark-recapture methods. We also suggest that DNA-based capture-mark-recapture methods would work more effectively if applied to large scale projects targeting the whole range of a local bear population.

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There has been only one study scientifically estimating the population size of brown bears (Ursus arctos yesoensis) on the Oshima Peninsula, Hokkaido, so far, although that estimate included a substantial margin of error. For more reliable results, we tried a mark-recapture method employing hair snagging. In the 3 years pre-survey, it was possible to get some hair samples using strained barbed wire and hanged lure in the middle of hair traps. Also, drying and storing hair samples properly in paper envelopes are essential procedures. Selecting adequate loci for individual identification is also important. Based on the results of the pre-survey, we conducted 3 years of hair snagging surveys using 29 or 39 hair trap sites. Through this latter survey, the homogeneity of habitat quality at each trap site and an adequate mesh size for population estimation are important issues to be considered.

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Direct observations have been conducted in the past to estimate the population size of the Asiatic black bear (Ursus thibetanus) in Iwate prefecture. To improve the precision of the population estimate, we applied a DNA-based method using hair-trapping since 2004. Through the experiences of these research projects, several problems have been identified concerning hair-trapping. First, there are structural problems to the trap. When we used a single strand of barbed wire, the hair collection rate was about 80 percent. By using two barbed wires each trap, we were able to collect hair samples in all traps. Secondly, the genotyping success rate of hair samples collected after August tended to decrease compared with those collected in June and July. DNA degradation was likely caused by the high temperature and humidity of summer. Another problem is that the placement of the trap was limited. Terrain irregularities and steep slopes disturbed, and sometimes prevented, the placement of traps. Therefore, it is necessary to develop a new trap not controlled by terrain conditions. By overcoming these problems one by one, we would continue to make progress on DNA-based population estimates using hair-traps.

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The density of Japanese black bears, Ursus thibetanus, living in the Kanto mountainous district of Nagano Prefecture has been estimated at 0.01–0.03/km² by conventional investigations: bear signs, direct observation at fixed points, and questionnaire surveys. Investigations by the hair trap method were executed in the Kanto mountainous district of Nagano Prefecture. One hundred hair traps were set and 679 hair samples were analyzed. We identified 33 bears by DNA analysis,and the success rate of our analysis was 26.3%. Results from the hair trap method suggest that density is underestimated by conventional methods.

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Three different situations are simultaneously occurring on two species of bear (Ursus arctos and U. thibetanus) in Japan: superficial range expansion, mass removals in certain years, and an increase in the number of threatened local populations. Evaluation of population viability should be incorporated into management. Management area should be classified into core areas where intensive research should be conducted, and ordinary areas where the results of research will be applied. The introduction of radiotelemetry will also be recommended. Comments on trap arrays were added to improve hair-trap method.

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It is important to develop monitoring methods of population trends for the brown bear (Ursus arctos) and the Asiatic black bear (U. thibetanus) in Japan. If we could evaluate population trends exactly, we could also estimate population sizes using population dynamics models with harvest data. The problem to be solved is the large-scale management of bear populations distributed over multiple prefectures.

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