We investigated mammal fauna of 12 public pastures in Tochigi prefecture, Japan, with two survey methods, camera trapping and field sign survey, and compared the results between these methods. We also examined the features of camera trapping data for future technical refinements. A total of 16 wild mammal species including 9 out of 13 medium-size and large-size mammal species in Tochigi were detected by camera trapping (12 species) and sign survey (14 species). Although the detectability of mammal signs was seasonally affected, such effects were not observed in camera trapping, suggesting that camera trapping is available throughout the year. The contingency of detected species and the correlation of abundance index (frequency of photos and signs) between these two methods were weak (kappa statistics: 0.43, 95% CI: 0.29-0.56) and mild (r=0.58, p<0.05), respectively. These methods were considered to be complementary. It took an average of 218.4 camera-days (range: 24.4-780.9) to reach the maximum species number detected in each pasture while a single remote camera per pasture was not enough to reach the maximum. There may be greater effectiveness of a fixed intermission between photographing in the remote cameras as suggested, comparing among different types of remote cameras. Practically, camera trapping in mammalian faunal surveys in pastures should be conducted with several remote cameras per pasture for at least 3 months with supplemental field sign surveys.

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In 2003, we investigated the effects of provisioning for sika deer (Cervus nippon) by tourists in Ebino Plateau, Kirishima, Miyazaki Prefecture. During the observations (total 71 hours), we found that a total number of 2,733 tourists (977 tour groups) had approached deer, and 579 tourists (183 tour groups) gave food to deer. The correlation between total number of tourists approaching deer and giving food was significant (r=0.898, F=41.875, p<0.0001), which accounted for 20% of total tourists that approached the deer. According to our observations, 70% of foods were snacks (potato chips, rice crackers, etc.) and an average of 0.63 of a snack bag was given by a tour group. In addition, the number of individual deer in a group fed by a tour group varied from 1 to 11 with an average of 4.8.
Additionally, the daily number of cars that parked in the visitor center parking lot was significantly correlated with both the daily number of tourists that gave food to deer (r=0.737, F=10.7, p<0.0014), and the daily number of tour groups that gave food (r=0.737, F=10.7, p<0.01). As a result, the total annual numbers of tourists and group tours giving food to deer could be estimated as 23,000 and 7,000, respectively.

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The Ryukyu flying-fox Pteropus dasymallus inopinatus was surveyed on islands adjacent to Okinawa Island from 1994 to 2005. We confirmed its occurrence on Kouri-jima, Ie-jima, Minna-jima, Ikei-jima, Miyagi-jima, Henza-jima, Hamahiga-jima, Tsuken-jima, and Kudaka-jima. Morphological characteristics of a flying-fox specimen previously obtained from Yoron Island indicate that bats on the island belong to the subspecies, P. d. inopinatus. On Yoron Island, at least five bats were counted simultaneously at the feeding sites in both summer and winter. The bats fed on Ficus superba and Terminalia catappa in spring, Morus australis and Garcinia subelliptica in summer and autumn, and Ficus microcarpa and F. superba in winter. Our observations, together with information from the inhabitants of Yoron Island, strongly suggest that the bats stay and breed on this island throughout the year, without seasonal migration to other islands.

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A total of 29 male specimens of Mustela killed by traffic accident on the road in Kagawa prefecture were identified by the relationship between head and body length (HBL) and tail length (TL), or hind foot length (HFL) and TL. However, the tail ratio (the proportion of TL to HBL), which is one of the method to distinguish between both species so far, is not adequate for the identification, because there is no difference between both the ratios (46.8% to 59.0% in M. sibirica coreana; 41.3% to 47.1% in M. itatsi). In addition, there seems to be no differences between both altitude distributions (5 m to 110 m in altitude in M. s. coreana; 5 m to 210 m in altitude in M. itatsi), according to the 29 specimens collected in this study.

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