Landscape restoration through revegetation is becoming an increasingly popular tool in the biodiversity conservation in highly fragmented landscapes. Although both patch area and connectivity are key factors driving species distribution and diversity in terrestrial fragmented landscapes, effects of these two factors were limited and mixed. Here we examined the effects of patch area and connectivity on the distribution of raccoon dog in Tokyo, central Japan. Camera traps were used to record continuously the activity of the raccoon dog for a total of 60 camera-nights within each 20 forest patches. Connectivity were defined was described by the total forest area within 600 m radius around a focal patch. Their areas ranted from 3.3 to 797.8 ha and their connectivity also varied.

The presence of adult individual was evident in all 20 patches, whereas adult with cub was found in 13 patches. Model selection of generalized linear models revealed the evident interaction effects between patch area and connectivity on the presence of adult with cub. Higher presence probability of adult with cub was shown in small-connected, large-connected, and large-isolated patches, and lowest probability was shown in only small-isolated patches. These results indicate that, for raccoon dog, the value as habitat is raised by improving habitat connectivity, even if small patches.