Yoshikazu Seki

Some wildlife species that have expanded their range into urban areas use various anthropogenic structures for breeding and resting. We investigated the use of seismically isolated buildings, with gaps between the structures and ground surface, by urban wildlife in Japan. Camera traps set in a building revealed that masked palm civets (Paguma larvata) continued to use the building for approximately 3 years. Civet feces and footprints were found in two buildings during field sign surveys. To ensure public health, civets should be prevented from invading seismically isolated buildings by covering gaps with elastic materials and avoiding placing pipes that could be used by the animals near these gaps.

Understanding the habitat selection patterns of animals is important for developing land-use plans for species conservation. The death of endangered Amami rabbits (Pentalagus furnessi), which are found only on two islands in Japan, due to vehicle collisions is a serious problem. To reduce the incidence of road kill and conserve the population of Amami rabbits, factors that contribute to the species’ proximity to roads need to be examined. We examined the habitat selection of Amami rabbits by counting their fecal pellet groups on roads on Tokuno-Shima Island, Japan. We obtained 101 presence observations, which revealed that Amami rabbits select areas close to natural forests, farmlands, and rivers and areas with steeper slopes. The selection by the species of natural forest and farmland is likely due to the availability of herbaceous and shrub plants at forest edges and crops and weeds in farmland for foraging. The high utilization of steep-sloping terrain could help Amami rabbits minimize predation risk from the native habu pit viper (Protobothrops flavoviridis). The frequent utilization of forest edges and farmland by Amami rabbits increases their risk of becoming road kill and the risk of crop damage, which are serious problems on the island. To prevent Amami rabbits from crossing roads and reduce crop damage, fences should be constructed particularly in high-rabbit-density areas, and should not facilitate population fragmentation of the species.

The Japanese serow (Capricornis crispus) and sika deer (Cervus nippon) in Japan are usually allopatric. However, a recent expansion in the distribution range of sika deer, combined with an increase in abundance, has resulted in an overlap of the distribution ranges of the two species. We examined the habitat selection and activity patterns of Japanese serows and sika deer using camera traps placed at 83 sites within a 210 km² study area, where the distribution range of these two species has recently overlapped. Although both species were photographed throughout the study area, we observed a low spatial overlap between them. The Japanese serows selected steep slopes, and the sika deer selected areas far away from human settlements. In addition, the Japanese serows and sika deer exhibited temporal partitioning with diurnal and crepuscular activity patterns, respectively. The observed partitioning could be explained by differences in their species-specific habitat selections, rather than competition, because the photographic capture rate of the Japanese serows was not affected by that of the sika deer and vice versa. These partitioning behaviors are likely to reduce the rate of encounters between the two ungulates, which enables their coexistence considering the sika deer density remains low.

The distribution of invasive alien Pallas’s squirrels ( Callosciurus erythraeus ) has expanded mainly toward the southeast with continuous forest in Kanagawa Prefecture, Japan. Recently, however, squirrels have been sighted in residential areas with only a few green spaces. We examined the habitat selection of squirrels in a city with small fragmented green spaces by censusing the animals along a 6.7 km route. Twenty-three presence data were obtained in 10 grids, which were much larger than the mean home ranges of the species, suggesting that a squirrel population had already been established in this area. Although woods of 5 ha, and 90% of presence data were obtained in green spaces with <5 ha. This indicates that squirrels can establish a population even in areas with small fragmented green spaces. The squirrels selected areas close to evergreen and deciduous woods, but they avoided those closer to residential areas. Since small fragmented woods, such as evergreen trees, are widely distributed in the central parts of Kanagawa Prefecture, the squirrels may use them as stepping stones to expand their range.