In this review, the various models to estimate wildlife abundance are organized for promoting the correct application of them in animal ecology. If individuals of the target wildlife are distinguishable, the capture-recapture (CR) model and the spatially explicit capture-recapture (SECR) model can be applied to the closed population and the Jolly-Seber (JS) model can be applied to the open population. If not, the distance sampling, N-mixture model, random encounter (RE) model, random encounter and staying time (REST) model, and removal sampling can be applied to the closed population, and the harvest-based model can be applied to the open population. Recent advances in the hierarchical model and the integrated population model (IPM) make it possible to model the abundance and demographic rate of the wildlife by considering the ecological process of the target wildlife and observation process of them and to utilize the various but fragmented data. Then, the formalization of the abundance estimation model as a hierarchical model and the construction of the IPM by considering the available data and biological characteristics of the target species are useful for future research.

Taiwan was considered rabies-free for > 50 years until the disease reemerged in its ferret badger population (Melogale moschata) in 2013. Although it is still expanding slowly northward in eastern Taiwan, its spread in the west has thus far been halted by the Da-An River. To prevent diffusion of rabies, an immunization zone should be established along the epidemic boundary before further rabies expansion crosses it. This study developed 19 microsatellite markers with tri- or tetra-nucleotide motifs specifically for ferret badgers using next generation sequencing, and we used these markers to evaluate level of gene flow across the Da-An River. Low levels of genetic differentiation and high levels of gene flow across the river indicated that the Da-An River was not a permanent barrier to rabies. Rabies may eventually be able to expand across this temporary boundary. We suggest that an immunization zone should be established along the Da-An River as soon as possible.

The Sunda porcupine (Hystrix javanica) is an endemic species of Indonesia. The population of this species has been decreased by hunting and habitat loss. Understanding of reproductive characteristics is essential for the appropriate management of their population. However, there is little knowledge about reproductive features of this species. The epididymis and deferent duct are important organs for maturation, transport, and storage of sperm. In this study, therefore, the epididymis and deferent duct of Sunda porcupines were examined histologically, histochemically, immunohistochemically, and electron-microscopically to understand their structures and functions. Four adult wild porcupines that inhabit Central Java, Indonesia, were captured in June and September and euthanized. Then, the epididymides and deferent ducts were removed. Principal cells were the main cell type found in the epididymis with stereocilia and apical blebs, but both of these structures were absent in the deferent duct. These observations suggest high secretion and absorption capability by the epididymal epithelium. In the epididymis and deferent duct, PAS-positive principal cells were shown, and the immunoreactivities for 3β-HSD were found in the epithelium of the deferent ducts. These reults suggest effects on sperm by glycoproteins and steroid metabolites.

Estimating population density and monitoring demographic trends of large carnivores are hard to be done, as they, in general, occur at very low population densities over large ranges and are often elusive. We tested the utility of artificially scented wooden rubbing posts as a tool for DNA hair snagging of brown bears (Ursus arctos), which can be used for noninvasive population monitoring. To determine which type of scents can attract bears, we applied various types of the scent lure [odor of brown bear, α-pinene (turpentine), and wood creosote oil] on wooden posts to compare with an unscented control, using 75 posts in total during 2009–2012. Among them, we confirmed that 23 posts were rubbed by bears at least once. The scent lures were selected as significant variables by a likelihood ratio test. Probability of rubbing by bears was the highest for wooden posts with creosote oil (57.6%). Our study offers a potentially effective means of DNA hair snagging by using artificially scented wooden rubbing posts.

The lesser bamboo rat is a fossorial rodent monotypic within the genus Cannomys, family Spalacidae. The present study revealed the first detailed information on its dental morphology, particularly the enamel microstructure, as examined by stereoscopic dissection and scanning electron microscopy. The lesser bamboo rat possesses proodont incisors covered with orange-pigmented enamel on the smooth front surface. The molars are mesodont-lophodont. The first upper molars are characterized by a tetralophodont (four lophs) pattern with four roots, whereas the first lower ones are pentalophodont and have three roots. Concerning the enamel microstructure, the incisors are comprised of a relatively thick Portio externa of radial enamel and prismless enamel (PLEX), and the Portio interna, formed by uniserial Hunter-Schreger Bands. Molar enamel microstructure shows a primitive (P)-type schmelzmuster with an occasional appearance of either irregular prism clusters or PLEX. The teeth and enamel of the lesser bamboo rat are somewhat different from those of other spalacid relatives. Although retaining a primitive state, they show some structural adaptations to feeding and tooth-digging lifestyles.

Like European badgers, Japanese badgers are known to use earthworms as a staple food. However, while European badgers mainly eat the family Lumbricidae, Japanese badgers are thought to primarily take the family Megascolecidae in forest areas. In this study, we investigated the feeding habits and habitat utilization of Japanese badgers inhabiting a mountainous dairy farm, where a previously less-investigated mosaic of forest and open areas occurred. Invertebrates, particularly earthworms and beetles, formed the bulk of badger diet throughout the study period, while the frequency of occurrence of fruit and larvae partially depended on their seasonal availabilities. Soil sampling showed that both Megascolecidae and Lumbricidae were present in the study area, with the former being more abundant in natural forests and the latter being more abundant in pastures. Furthermore, their seasonal availability showed opposite patterns, with biomasses being the highest in summer for Megascolecidae and in spring and fall for Lumbricidae, resulting in the total biomass of earthworms in the whole study area remaining relatively consistent between seasons. Habitat use by Japanese badgers did not mirror food availability, pastures and natural forests being preferred throughout the year.

The masked palm civet (Paguma larvata) in Japan is considered as an alien species; however, the details on introduction routes to Japan and the expansion history are still unclear. In the present study, to further solve these questions, we analyzed the mitochondrial DNA control region (523 base-pairs) of 226 individuals from Japan and Taiwan, and identified 13 haplotypes, which are phylogenetically closely related to each other. Then, we combined the present control region data with the previously reported cytochrome b sequences, and found multiple haplotypes in Shikoku, Gunma, and Tokyo. The population in Shikoku was formed by several genetic lineages, one of which was not found in other areas, indicating the differentiation of the Shikoku population from those in Central Honshu. In addition, animals with the major cytochrome b haplotype in Eastern Japan in the previous study were found to have three different haplotypes in control region. The results strongly show multiple introduced routes of P. larvata in Eastern Japan. Our study much contributes to further understanding of the expansion history of P. larvata on the Japanese islands, in conjunction with previous genetic data.

Forefoot characteristics of the Ryukyu long-furred rat, Diplothrix legata, in the Amami-oshima, Tokunoshima, and Okinawajima Islands of the southern part of Japan (the Nansei Archipelago), were analyzed morphologically considering its arboreal lifestyle. The presence of a nail on the pollex was confirmed and seemed to be regarded as an arboreal feature, based on the presence of nails in other arboreal murids reported in previous studies. In addition, a linear palmar groove was confirmed between the interdigital pads and the thenar-hypothenar pads. We tried to allow the forefoot to take hold of a thin stick at this groove; the stick fit well in the groove, and it seemed to be possible to grip by the fingers except for pollex. Thus, the sizes and positions of palmar swollen pads forming the linear groove were considered to be useful for gripping a thin twig in an arboreal lifestyle. In addition, the entire unguis size tended to be larger in Okinawajima Island than in Amami-oshima Island as a geographical variation.

A 15-month camera-trapping study (7302 camera-days) was done in Gunung Ledang Johor National Park on the southern Malay Peninsula from July 2018 to October 2019. Six video images of the endangered Sumatran serow, Capricornis sumatraensis (Bovidae, Cetartiodactyla), were obtained. This is the first confirmation of a wild population of the species on the southern Malay Peninsula. Serows were photographed at elevations of 500–1189 m from hill dipterocarp forest to montane ericaceous forest. Their size suggests that the individuals were adults. Gunung Ledang is an isolated, well-forested mountain surrounded by oil palm plantations, roads, and human settlements, suggesting that the serow population in the area is completely isolated from the other populations. Further studies are needed to evaluate the population status of the Sumatran serow in the area, as it represents the extreme southern limit of the species' distribution in the Continent of Asia, except Sumatra.